Sector Project Mechanical-biological Waste...
Transcript of Sector Project Mechanical-biological Waste...
Sector ProjectMechanical-biological Waste TreatmentFinal Report
Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ ) GmbH
Division 44Environment & Infrastructure
Published by
Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) GmbHDag-Hammarskjöld-Weg 1-565760 Eschborn / Germany
Desk OfficerElke Hüttner (GTZ, Division 44 - Environment & Infrastructure)
EditingGernod Dilewski (INFRASTRUKTUR & UMWELT, Darmstadt), Joachim Stretz (Berlin)
in cooperation withGabriele Janikowski (IKW Beratungsinstitut fürKommunalwirtschaft GmbH, Cologne),Dr. Dirk Maak (Wilhelm Faber GmbH, Alzey), Dr. Aber Mohamad (University of Kassel),Dr. Dieter Mutz (Basel University of Applied Sciences - FHBB), Bernhard Schenk (Berlin)
DesignChristopher Heck•eyes-luna Multimedia-Design •, D- 64291 Darmstadt
Printed byDigitaldruck Darmstadt GmbH & Co. KG
Eschborn 2003
1
CONTENT
This report presents the main activities and results of the sector project "Promotion of Mechanical-
biological Waste Treatment", which was conducted by Deutsche Gesellschaft für Technische
Zusammenarbeit (GTZ) GmbH on behalf of the Federal German Ministry for Economic Cooperation
and Development (BMZ) between 1998 and 2003. The focal areas of the sector project were a trio of
pilot projects in São Sebastião (Brazil), Phitsanulok (Thailand), and Al-Salamieh (Syria), in which
mechanical-biological waste treatment (MBWT) options were field-tested under the relevant local
boundary conditions. All three pilot projects yielded satisfactory results following appropriate adapta-
tion of the decomposition process. The specific costs of MBWT ranged between 11 and 15 Euro/Mg
in all three cases. However, these expenditures are at least partially compensated by the resultant
savings in landfilling.
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1 Introduction and Rationale 8
2 Introduction to MBWT 10
2.1 Characterization of MBWT 10
2.2 Waste Treatment Processes 11
2.3 Integration of MBWT into Municipal Waste Management Schemes 12
2.4 Climatic Factors 13
3 MBWT Reference Material and Events 15
3.1 MBWT Decision-maker's Guide 15
3.2 Videos 15
3.3 Costing Model 16
3.4 Conferences and Seminars 16
4 MBWT Pilot Projects 18
4.1 Short Descriptions of the Projects 18
4.1.1 Pilot project in São Sebastião, Brazil 18
4.1.2 Pilot project in Phitsanulok, Thailand 19
4.1.3 Scale-model MBWT trial in Al-Salamieh, Syria 19
4.1.4 Other projects 21
4.2 Results and Experience Gathered from Pilot Projects 22
4.2.1 Project preparation 23
4.2.2 Monitoring programs 23
4.2.2.1 Basic principles 23
4.2.2.2 Implementation via pilot projects 24
4.2.3 IMBWT processes employed in the pilot projects 25
4.2.3.1 Technology selection criteria 26
4.2.3.2 The Al-Salamieh scale-model trial 27
4.2.3.3 The FABER-AMBRA® process in
São Sebastião and Phitsanulok 28
4.2.3.4 Evaluation of the technologies employed 30
4.2.4 Operation of an MBWT facility 31
4.2.4.1 MBWT personnel requirements 32
4.2.4.2 Training 32
4.2.4.3 Integration into the organizational structures 33
4.2.5 Chronology and results of aerobic decomposition 34
4.2.5.1 Time history of in-heap temperatures 34
4.2.5.2 Effects of rainy season on the temperature curve 36
4.2.5.3 Gas composition 37
4.2.5.4 Water content 40
4.2.5.5 Solids and eluate analyses 40
4.2.5.6 Results of composting trials in
Al-Salamieh, Syria 41
Table of contents
4.2.6 Emissions from MBWT 43
4.2.6.1 Basic principles 43
4.2.6.2 Odors 44
4.2.6.3 Hygiene 44
4.2.6.4 Process water 44
4.2.6.5 Methane emissions 48
4.2.7 Disposal of pretreated waste to the landfill 48
4.2.7.1 Fundamental considerations 48
4.2.7.2 Mass reduction determined in the pilot projects 51
4.2.7.3 Emplacement trials in the pilot projects 52
4.2.7.4 Landfill leachate in São Sebastião 54
4.2.8 Costs 54
4.2.8.1 Costing principles 54
4.2.8.2 Examples of costs incurred in the pilot projects 55
4.2.8.3 Effects of MBWT on the cost of waste dis-posal 60
4.2.9 Informal sector 61
5 Future Prospects of MBWT in Developing and Threshold Countries 64
5.1 Conclusions Drawn from the Pilot Projects 64
5.2 Comparison of Alternative Waste Disposal Concepts 66
5.3 Need for Further Study 67
6 Summary 69
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APPENDICES
Appendix 1 Characterization of the Pilot Projects
Appendix 2 List of Important Contacts
Appendix 3 Bibliography
LIST OF TABLES
Table 1: Differences between composting and MBWT 10
Table 2: Anthropogenic emissions of CO2, CH4, and N2O within the EU in 1994 [1] 14
Table 3: Proposed monitoring program for the pilot-scale field trial in Phitsanulok 24
Table 4: Personnel requirements for MBWT operations in São Sebastião
(throughput: 30,000 Mg/a) 32
Table 5: Backstopping work scope for Faber during the one-year imple-
mentation phase in São Sebastião 32
Table 6: Water content of waste inputs in the pilot projects 40
Table 7: Results of treated -waste analysis in São Sebastião 41
Table 8: Heavy-metal contents as a function of input material 42
Table 9: Quantity and quality of process water from biotreatment wind-
rows in the Al-Salamieh scale-model trial 45
Table 10: Mass reduction through biotreatment in the Al-Salamieh,
Syria, scale-model trials 51
Table 11: Comparison of specific costs in the pilot projects 58
LIST OF FIGURES
Figure 1: The "Alvarenga" garbage dump in Sao Paulo, and the "Billings"
drinking water impounding reservoir Source: GTZ Photo Archive 8
Figure 2: The operational sequence of mechanical-biological waste treatment 10
Figure 3: A natural-draft (convecting) biotreatment windrow as an exam-
ple of extensive aerobic decomposition 11
Figure 4: Schematic rendition of an intensive aerobic decomposition process 12
Figure 5: Residual-waste treatment options 13
Figure 6: At the entrepreneurs' forum on "Public Private Partnerships
(PPP) in the International Waste Sector", in Eschborn, Germany 17
Figure 7: Mechanical-biological waste treatment using the FABER-AMBRA®
process in São Sebastião 18
Figure 8: Mechanical-biological waste treatment using the FABER-AMBRA®
‘process in Phitsanulok 19
Figure 9: Composting windrow in Al-Salamieh, with cover and forced ventilation 20
Figure 10: Training for Recicladores at the scale-model MBWT facility in
Armenia, Colombia 22
Figure 11: A typical decomposition temperature curve 23
Figure 12: Temperature monitoring with a sampling gauge in Phitsanulok 25
Figure 13: Waste pickers at the Phitsanulok landfill 26
Figure 14: Compost heaps during the model experiment in Al-Salamieh 27
Figure 15: Homogenizing drum at work in Phitsanulok 28
Figure 16: Waste from Phitsanulok before and after homogenization 29
Figure 17: Piling the waste for biological treatment in Atlacomulco, Mexico 29
Figure 18: Training for technical personnel at the Phitsanulok landfill 32
Figure 19: Theoretically achievable and actual throughput at the MBWT
facility of the Phitsanulok pilot project 33
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Figure 20: Time history of in-heap temperatures in the Al-Salamieh scale-model trial 35
Figure 21: Time history of in-heap temperatures in São Sebastião 35
Figure 22: Time history of temperatures in a FABER-AMBRA® heap
Exposed to heavy precipitation 36
Figure 23: Relationship between oxygen content and carbon dioxide concentration 37
Figure 24: Waterlogged base of a heap showing evidence of anaerobic decomposition 38
Figure 25: Results of gas monitoring at heaps C and D on
February 13, 2003, in Phitsanulok 39
Figure 26: Coconut-shell biofilter at the Phitsanulok MBWT facility 44
Figure 27: Test heap in São Sebastião 45
Figure 28: Cumulative curves showing the precipitation onto and the pro-
cess water volume emerging from the test heap in São Sebastião 46
Figure 29: Quality of process water from test heaps in Rio de Janeiro
and São Sebastião 47
Figure 30: Process water seeping out from the base of a heap in São Sebastião 47
Figure 31: Densities of compaction with and without pretreatment [6] 49
Figure 32: Emplacement of pretreated waste in São Sebastião 51
Figure 33: Mass reduction in the pilot phase of MBWT in Phitsanulok 51
Figure 34: Test-field dimensions for the commercial-scale compaction trial 52
Figure 35: Dry-season emplacement trial for pretreated waste at the
Phitsanulok landfill in Thailand 52
Figure 36: Comparison of in-heap densities and achieved landfill
compaction densities 53
Figure 37: Leachate burden at the MBWT landfill in São Sebastião 54
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Figure 38: Comparison of pilot-project cost calculations (specific costs in EUR/Mg) 59
Figure 39: Comparison of specific landfilling costs in Phitsanulok with and
without MBWT (specific costs in EUR/Mg) 61
Figure 40: Informal-sector intervention in the flow of household waste 61
Figure 41: Members of the Ilhabela Cooperative at work sorting recyclables 62
Figure 42: Avenues of waste disposal in the member countries of the EU in 1999 [7] 66
Sector Project MBWT - Final Report
In many developing countries, shifting living
habits in conjunction with increasing urbaniza-
tion and industrialization are strongly influencing
the volumes and composition of waste inci-
dence. As waste volumes expand and contain
ever larger quantities of packaging material and
hazardous substances, traditional forms of
waste disposal reach their limits, and in many
places new waste-disposal strategies have to be
devised to protect human health and avert en-
vironmental pollution.
Recent years have seen much progress made in
the area of waste collection. In contrast, there
has been little good news about waste disposal
in developing and threshold countries. Most
waste is still being disposed of at uncontrolled
dumps (fly tips) where no special measures are
taken to prevent pollution. Emissions from such
dumps jeopardize the health of nearby resi-
dents, contaminate the surrounding soil, and
threaten groundwater resources.
Consequently, people have in recent years
begun to speak out against this kind of waste
disposal. Particularly in large cities, it is beco-
ming increasingly difficult to find and provide the
necessary deposition capacities. Even if more
waste can be avoided and recycled in the future,
landfills will still be needed in the years to come
to accommodate the remaining unrecyclable
waste.
The environmental burdens resulting from the
disposal of residual waste can be reduced most
effectively by intelligent selection of landfill loca-
tions, structural measures (e.g. liners) and opti-
mized modes of landfill operation. In addition,
waste can be pretreated to modify its properties
so that less pollution will result when it is dum-
ped. One means of pretreatment is to incinerate
the waste, although the resultant slag and the
residue from the off-gas scrubbing system still
have to be disposed of afterwards. In Europe,
recent years have seen the emergence of
mechanical-biological waste treatment (MBWT)
as an alternative, or complement, to waste inci-
neration. Germany is a global leader in the
design and use of MBWT technology.
Especially the organic fraction of municipal solid
waste (MSW) constitutes a serious environmen-
tal risk when dumped at landfills, because it will
subsequently undergo uncontrolled biological
decomposition. The basic idea of MBWT, there-
fore, is to pretreat such waste under controlled
conditions prior to its ultimate disposal in order
to optimize decomposition of the organic frac-
tion, hence reducing its pollution potential.
Mechanical-biological waste treatment can, sub-
ject to certain conditions, be significantly more
cost-effective than waste incineration and is
therefore viewed as an attractive alternative
technology. However, little experience has been
gained to date in the use of this technology in
developing and threshold countries.
1 Introduction and Rationale
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Figure 1: The "Alvarenga" garbage dump in Sao Paulo, andthe "Billings" drinking water impounding reservoirSource: GTZ Photo Archive
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Past attempts to transfer waste technologies
from industrialized countries of the West to
developing countries have led to numerous
disappointments. Hence it was not the sole
objective of the GTZ sector project "Promotion
of Mechanical-biological Waste Treatment" to
simply disseminate the technology, but also and
in particular to carry out a critical analysis of the
risks and potentials of MBWT. The pilot-scale
MBWT field tests conducted in various countries
provide the main basis for this analysis.
The sector project focused on both the technical
components and some key areas of develop-
ment policy, including in particular the living
conditions of waste pickers and how they would
be affected by the introduction of mechanical-
biological waste treatment.
The sector project "Promotion of Mechanical-
biological Waste Treatment" was designed for a
term of six years (1998 - 2003) and was finan-
ced by the Federal German Ministry for Econo-
mic Cooperation and Development (BMZ). Its
focal areas were:
generating and providing reference material
on MBWT,
conducting seminars and training events,
elaborating feasibility studies for MBWT
developing countries, including the explora-
tion of socioeconomic aspects,
planning and implementing exemplary pilot-
scale applications with scientific back-
stopping.
Numerous German and foreign partners were
attracted to the project to help implement its
activities:
Federal German Ministry of Education and
Research (BMBF)
Knoten Weimar
the Faber Group
the University of Kassel
Prefeitura São Sebastião
Prefeitura Municipal Ilhabela
Municipality of Phitsanulok
The individual project partners' names, addres-
ses and contact persons are listed in the
Appendix.
The primary goal of MBWT is to minimize
the environmental burdens of waste dis-
posal by way of extensive stabilization. MBWT
can also help to recover valuable materials (cf.
Chapter 2.3). The terms composting and MBWT
are often used together, because both approa-
ches rely on quite similar techniques. However,
the two processes do pursue different objectives
(cf. Table 1).
2.1 Characterization of MBWT
As shown in Figure 2, MBWT generally compri-
ses the following steps:
waste input and control,
mechanical conditioning,
biological treatment and
emplacement of treated waste at a landfill.
In the mechanical stage, the first step is to sort
out the disturbants (e.g. large pieces of metal),
unwanted materials and - optionally - recycla-
bles. Next, the residual waste is prepared for
biological treatment by comminution, mixing
and, if necessary, moistening. Then comes the
biological stage, the purpose of which is to
effect extensive biological stabilization of the
waste. There are two basic methods of biologi-
cal decomposition:
aerobic decomposition, i.e. decomposition
in the presence of atmospheric oxygen, and
anaerobic digestion, i.e. decomposition
the absence of atmospheric oxygen, also
referred to as fermenting.
The biological decomposition and conversion of
organic matter by microorganisms (bacterial,
protozoa, fungi) is a natural form of recycling
that takes place in landfilled waste. As biological
decomposition progresses in a landfill, anaer-
obic digestion generates a combustible, explosi-
ve gas referred to as sanitary landfill gas. This
gas escapes from the landfill and contributes to
global warming and hence to climate degra-
dation. Water seeping into the landfill, together
with water contained in the waste, becomes
contaminated by the products of decomposition
and by the leaching out of pollutants.
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2 Introduction to MBWT
Process Main objective Input
Composting To obtain a high-quality,marketable soil conditio-ner (compost)
Defined inputs with decisiveinfluence on the quality ofthe product (e.g. separatelycollected biowaste)
MBWT To minimize, by means ofextensive stabilization, theenvironmental pollution re-sulting from waste dispo-sal
Mixed municipal solidwaste (MSW)
Tabelle 1: Differences between composting and MBWT
Iner
t fr
actio
ns
NonbiodegradablesRecyclablesHigh-Energy
Fraction
Waste input and control
Disposal to landfill
Mechanical conditioning
Coarse sorting ScreeningSorting CombinutionMagnetic Separation Homogenization
Biological treatment
Aerobic Anaerobic/AerobicDecomposition Ferm. + post-decomp.
Screening
Optional
Sew
age
slud
ge
Co
ver
Figure 2: The operational sequence of mechanical-biological waste treatment
To keep the leachate and the landfill gas from
escaping to the environment, the landfill needs
to be sealed so that they can be collected and
treated systematically.
Through the controlled decomposition of organic
substances, mechanical-biological waste treat-
ment substantially reduces both the gas and
water emissions which would otherwise be sub-
sequently generated at the landfill and the volu-
me of the residual waste requiring emplacement.
Waste containing a large share of biodegradable
organic material is most suitable for such treat-
ment. This is generally the case for household
and commercial waste. However, contaminated
waste, e.g. hazardous industrial waste; infec-
tious waste, e.g. waste from hospitals and
slaughterhouses; and constructionsite waste are
inherently unsuitable. The suitability of industrial
waste needs to be determined in advance, e.g.
by analyzing, on a case-by-case basis, its pollu-
tant concentrations and biomass fractions.
2.2 Waste Treatment Processes
There is a broad spectrum of equipment and
biological treatment methods that can be com-
bined for the purposes of mechanical-biological
waste treatment, depending on the local situa-
tion and the waste-management targets. For
example, some facilities are modestly equipped
and are operated using extensive-type proces-
ses, i.e. processes involving little automation
and low outlays for construction and process
control.
11
Ventilating pipes
Rows of pallets
~20 cm
~60 m
~2,5 m
Wind
Base ~25 m
BiofilterAtmospheric
pressure
Slope approx.ca. 3%
Fresh airExhaust air
Homogenized waste
Figure 3: A natural-draft (convecting) biotreatment windrow as an example of extensive aerobic decomposition
Conversely, depending on the set objectives of
treatment, the financial leeway, and various
other boundary conditions, biological treatment
can also be pursued using semiautomatic, tech-
nically optimized, indoor, emission-controlled
systems (intensive approach).
Intensive approaches help reduce the decompo-
sing time and the specific space requirements.
Closed systems (hall, container) allow emissions
(gas, odor, dust, ...) to be controlled. Also, the
decomposition process can be controlled and
optimized by way of active ventilation, moisturi-
zing and blending. This significantly accelerates
the main decomposition process and increases
the share of organic matter that actually decom-
poses. However, the structure and the requisite
equipment make this approach too expensive
for anything but large amounts of waste, and the
high degree of automation makes the system
more susceptible to disturbances and therefore
necessitates higher expenditures for maintenan-
ce and repair.
2.3 Integration of MBWT into Municipal
Waste Management Schemes
The first step toward determining the extent to
which MBWT may or may not constitute a good
approach to waste management for a given city
or region is to survey and analyze the existing
waste-management situation.
Prior to deciding in favor of mechanical-biologi-
cal waste treatment, other waste-treatment
alternatives should also be considered. In indu-
strialized countries, for example, waste incinera-
tion is a fairly popular form of residual-waste
treatment. The flue-gas emissions are of primary
interest when evaluating environmental pollution
from waste incineration plants (WIPs).
Sector Project MBWT - Final Report
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Exhaust-air
scrubbing
Post-treatment,landfill
Automatic turning and moisturi-zing of decomposting material
Moisturization withprocess water
Mechanicalconditioned
waste
Exhaust-air
scrubbing
Closed Hall
Vacuum ventilation
Figure 4: Schematic rendition of an intensive aerobic decomposition process
In recent years many countries have adopted
emission standards for the control of flue-gas
emissions from waste incinerating plants. Com-
plying with such standards necessitates very
high process-technological and financial invest-
ments. Such plants are designed for high
throughputs with a view to minimizing the speci-
fic costs.
Mechanical-biological waste treatment facilities,
though, can operate economically for smaller
quantities, as well. MBWT facilities can be
expected to cost a fraction of the outlay for
waste incinerating plants. Moreover, the pro-
cess-technological requirements - in other
words the initial cost of the plant - can, within
certain limits, be defined by the owners / buil-
ders themselves without necessarily having to
fear that the quality of treatment will deteriorate
as a result.
In professional circles MBWT is therefore
discussed as a more economical and less com-
plicated alternative to waste incineration. On the
other hand, especially for large volumes of
waste material, MBWT and waste incineration
can make a good combination. In a basic model
of such an approach, high-energy waste materi-
als such as plastics and composites are separa-
ted from the biodegradable waste. While the
energy content of the former is exploited, the
organic fraction undergoes biological treatment
and subsequent disposal to a landfill.
In many different countries, recent years have
seen the installation of organic waste compo-
sting facilities (primarily for prunings and kitchen
slops). As a rule of thumb, the composting of
separately collected kitchen slops and garden
waste can always be regarded as useful, whet-
her or not mechanical-biological waste treat-
ment is introduced.
2.4 Climatic Factors
Human activities have caused a considerable
increase in the greenhouse-gas contents of the
earth's atmosphere. As a consequence, the
earth's surface is expected to become gradually
warmer over the coming decades (global wam-
ing), in turn giving rise to attendant climatic
changes. Knowing this, the industrialized coun-
tries have adopted the United Nations Frame-
work Convention on Climate Change (Kyoto
Protocol), in which they agree to reduce their
greenhouse gas emissions.
The greenhouse gases that are contributing
most to the greenhouse effect are carbon dioxi-
de (CO2), methane (CH4) and nitrous oxide or
laughing gas (N2O). All three of them occur inter
alia in connection with waste disposal. Table 2,
below, reflects the estimated total emissions of
these gases within the EU, including the respec-
tive fractions attributable to waste disposal.
13
Figure 5: Residual-waste treatment options
Mechanical-biological
treatment
Thermal treatment
Disposal to landfill
high - energy fraction
Untreated waste input
Conventionallandfill
WIP
Slag-dump
MBWT
WIP orenergy rec.
MBWT-landfill
MBWT
Most of the greenhouse effect attributable to
waste management can be ascribed to metha-
ne, which is produced by the anaerobic diges-
tion of biodegradable waste in landfills. Approxi-
mately one-third of all anthropogenic CH4 emis-
sions within the EU derive from that source. By
contrast, only 1 % of the N2O emissions and
less than 0.5 % of the CO2 emissions can be
traced to landfilled waste. Hence, reducing CH4emissions from landfills holds the greatest
potential for reducing greenhouse gas emissions
in the waste-management context.
MBWT allows methane generation to be greatly
reduced. Well-ventilated, long-term aerobic
decomposition emits only about 1 % of the
methane generated by a comparably sized land -
fill full of untreated waste. Anaerobic processes
offer certain advantages over aerobic processes
with regard to climatic effects because the bio-
gas they produce contains a large proportion of
methane and is therefore a useful energy vehi-
cle, and they produce only small amounts of
exhaust air, i.e. off-gas, that can scrubbed befo-
re it is released to the atmosphere.
Another way to reduce methane emissions from
landfills is to cover the older parts of the dump
with a biofilter cap consisting of pretreated,
screened waste. The filter layer helps diminish
the amount of methane that can escape from
the landfill.
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14
Greenhouse gas Emissions Greenhousepotential
Total greenhouse potentialof all emissions
Greenhouse potential ofemissions from waste
disposal
Units [Gg] (over 100 years) [Gg] in CO2- equiv. em.(with waste-disposal fraction, in
wt.%, parenthesized)
[Gg] in CO2- equiv. em. (with waste-disposal distribution
parenthesized))
CO2 fossil 3.215 1 3.215 (< 0,5%) 15 (9%)
CH4 22 21 460 (33%) 152 (89%)
N2O 1,05 310 325 (1%) 3 (2%)
Total 3.237 4.000 (4,25%) 170
Table 2: Anthropogenic emissions of CO2, CH4, and N2O within the EU in 1994 [1]
3.1 MBWT Decision-maker's Guide
Within the scope of the sector project, a
compact decision-maker's guide1 on
mechanical-biological waste treatment in deve-
loping countries offers a wealth of relevant infor-
mation. It contains concrete decision-making
aids to help decide whether or not this treatment
method would help improve the waste-disposal
situation under a given set of circumstances.
The main contents of the guide are:
a brief explanation and presentation of the
various stages and processes of MBWT and
of its impacts
a basic approach to the estimation of costs
an explanation of how mechanical-biological
waste treatment fits into municipal waste
management, including a survey of alternati-
ve methods of waste treatment
tools for arriving at an initial decision on
whether or not, and how, MBWT can be
sensibly employed under the prevailing set
of boundary conditions
helpful hints on further lines of action, and
information on pertinent and supplementary
sources of information.
The guide addresses all interested in waste
management in developing countries. This inclu-
des municipal decision-makers as well as diver-
se experts and consultants in the field of waste
management.
3.2 Videos
Serving as an initial introduction to the subject
of MBWT, a presentation in the form of a video
film entitled "Mechanical-biological Waste Treat-
ment in Germany" has been produced by the
sector project. Available in English, Spanish,
Portuguese and Thai, the film illustrates the
basic procedures and the span of MBWT's tech-
nical implementation at various sites in Germa-
ny.
Following an introductory awareness-raising
section on waste disposal in a general context,
MBWT is presented as a potential alternative
with the capacity to ameliorate the relevant envi-
ronmental impacts. The presentation has four
main sections, each dealing with a different sta-
ge of the process:
waste input and control
mechanical conditioning
biological treatment
disposal of residual waste to landfill
Various processes are dealt with, e.g. natural-
draft decomposition, the dome-aeration method,
and some technically more complicated, dyna-
mic, intensive-decomposition approaches.
Another film, produced by Faber, explains the
FABER-AMBRA® process as employed in Ger-
many and Brazil. This film is also included in the
sector project's documentation.
15
3 MBWT Reference Material and Events
1 A PDF version of the guide is available in German, English and Spanish at www.gtz.de/MBA.
3.3 Costing Model
To help estimate the initial investment costs and
the cost of operating an MBWT facility, a costing
module based on a question-and-answer appro-
ach has been developed. It allows the user to
arrive at a cost estimate by entering the relevant
data appropriate to the local situation. The user
should, of course, have some idea of how
MBWT works, because the program includes
multiple-choice questions about such matters as
procedural alternatives.2
The costs to be taken into account are based on
empirical data gleaned from the German / Euro-
pean market. To find out what those costs
would amount to in one's own country, the user
has to estimate and enter a correction factor to
account for, say, the cost of importing the requi-
site mechanical equipment (customs, cost of
transportation, ...). Naturally, the cost of con-
struction must be based on local wage levels.
The program was designed for application to
facilities with throughputs of 20,000 Mg/a and
higher. Sizing of the biological treatment stage
assumes as its treatment target that the biologi-
cal activity of the treated material will amount to
approximately one quarter of that of fresh mate-
rial. While this does not correspond to Ger-
many's stringent requirements for the disposal
of biologically pretreated waste, it does hold the
promise of substantial improvements with regard
to emissions and landfilling space require-
ments.
The program provides an initial overview of the
costs to be expected for various alternative vari-
ants. However, detailed planning with due allow-
ance for the local framework conditions is
necessary for reliable costing.
3.4 Conferences and Seminars
Numerous events dedicated to MBWT were held
in Germany and in the partner countries in the
course of the sector project. They included:
1. a workshop entitled Mechanisch-biologische
Abfallbehandlung in Entwicklungsländern
(mechanical-biological waste treatment in deve-
loping countries) serving to help establish co-
operative relationships with German facility ope-
rators, engineering companies, technology-
transfer organizations and academic institutions.
March 18, 1999, in Eschborn, Germany
2. a sectoral forum entitled Mechanisch-biologi-
sche Abfallbehandlung in Entwicklungsländern
(mechanical-biological waste treatment in deve-
loping countries) held in cooperation with Kno-
ten Weimar, dealing with methods of mechani-
cal-biological waste treatment, as employed
under circumstances specific to developing
countries. July 22/23, 1999, in Eschborn, Ger-
many
3. a training course in mechanical-biological
waste treatment for Thai specialists representing
municipal authorities, held in cooperation with
the Technical Cooperation Project "Solid Waste
Management Programme for Phitsanulok". Sep-
tember 1/8, 1999, in Germany
4. a workshop on mechanical-biological waste
treatment for Brazilian communities and univer-
sities, held in cooperation with "Wilhelm Faber
GmbH" and Prefeitura Municipal de São Se-
bastião. December 6/7, 1999, in São Sebastião,
Brazil
Sector Project MBWT - Final Report
16
2 This information can be found, inter alia, in the aforementioned decision-maker's guide.
5. a workshop for recycling and waste-sorting
cooperatives, held in cooperation with Prefeitura
Municipal de São Sebastião. September 23/26,
2000, in São Sebastião, Brazil.
6. a workshop and training event entitled "Pilot
Project on Waste Management in Atlacomulco",
sponsored by Wilhelm Faber GmbH for the City
of Atlacomulco and other Mexican communities.
September 2002, in Atlacomulco, Mexico.
7. an entrepreneurs' forum entitled "Public Pri-
vate Partnerships (PPP) in the International
Waste Sector", held in cooperation with Knoten
Weimar. The purpose of this forum was to join
with representatives of the industrial sector,
government ministries, promotion institutions,
consultants and experts in evaluating PPP as a
still-young instrument and developing future
strategies. Concrete steps toward improving
PPP as a tool were agreed and implemented.
August 2/3, 2001, in Eschborn, Germany, plus
two "follow-up meetings" by the members of the
initiative on December 6, 2001, in Braun-
schweig, Germany, and on May 15, 2002 at
IFAT.
The partners participating in the pilot projects
held additional training / information events and
seminars for their local specialists. Documenta-
tion of the aforementioned events is available via
the sector project's own documentation and the
website www.gtz.de/MBA.
17
Figure 6: At the entrepreneurs' forum on"Public Private Partnerships (PPP) in theInternational Waste Sector", in Eschborn,Germany
4.1 Short Descriptions of the Projects
Within the scope of the sector project,
various pilot projects were implemented
in cooperation between partners in the project
countries, German enterprises and GTZ. The
main objective of the projects was to appraise
the appropriateness of known German approa-
ches for application in the various countries and
to evaluate the prospects and risks of the tech-
nology in the relevant country. The projects
enjoyed scientific backstopping, and their
results were evaluated by independent experts.
The individual projects are outlined below, and
condensed descriptions of the projects are pro-
vided in the project characterizations attached
to this report.
4.1.1 Pilot project in São Sebastião, Brazil
In cooperation with Prefeitura Municipal de São
Sebastião, the project implemented a mechani-
cal-biological waste treatment (MBWT) plant in
São Sebastião, in the Brazilian State of São
Paulo. São Sebastião, a town of scarcely 50,000
inhabitants, is such a popular tourist destination
that its population swells to over 250,000 during
the main tourist season. With a view to impro-
ving the town's previously inadequate waste dis-
posal capabilities, the German company Wilhelm
Faber GmbH installed an MBWT facility that
works on the basis of the FABER-AMBRA® pro-
cess (cf. Chapter 4.2.3.3).
Firstly, a trial decomposing heap based on the
FABER-AMBRA® process was established and
studied in Rio de Janeiro. Then, in May 2000, a
six-month trial commenced in São Sebastião.
The trial was attended and evaluated both by
Wilhelm Faber GmbH and by independent
experts from GTZ. Some minor adjustments
were made in the process to accommodate
local factors, with a bearing on, for example,
homogenization and moisturizing of the waste
and disposal of the process water. Once the
process was seen to have demonstrated its fun-
damental suitability in the course of trial opera-
tion, MBWT was successively expanded and
integrated into São Sebastião's waste manage-
ment system.
Now, since April 2002, all domestic waste arri-
ving at the landfill undergoes mechanical-biolo-
gical pretreatment, and no more waste is depo-
sited at the old dump. The old dump has since
been profiled and covered with cohesive soil.
After that, additional biotreatment windrows
were established on the covered area, and all
pretreated waste is now being emplaced in
separate sections of the landfill. Operation of
both the landfill and the MBWT facility has been
privatized. The City of São Sebastião has char-
ged Faber with providing technical support for
the MBWT.
4 MBWT Pilot Projects
Sector Project MBWT - Final Report
18
Figure 7: Mechanical-biological waste treatment using theFABER-AMBRA® process in São Sebastião
4.1.2 Pilot project in Phitsanulok, Thailand
In November 2001 a pilot project at the Phit-
sanulok municipal landfill was commenced on
the basis of a GTZ-commissioned feasibility stu-
dy produced in 1999 on the suitability of mecha-
nical-biological waste treatment for the city. The
purpose of this experiment was to demonstrate
that the FABER-AMBRA® process can also be
successfully applied in cases involving very
moist, weakly structured waste materials contai-
ning large amounts of plastics. Another goal was
to clarify the extent to which high rates of preci-
pitation during the rainy season would cause
problems with the open-air decomposing heaps.
The project was conducted in cooperation with
the City of Phitsanulok and with the support of
the Technical Cooperation project "Thai-German
Solid Waste Management Programme for Phit-
sanulok."
The MBWT process employed is basically the
same as in São Sebastião. The waste is homo-
genized at a rate of 50 Mg/d in a mobile drum
provided by Faber. Since the project is still in its
pilot phase, no ultimate throughput targets are
being achieved yet. The pilot project is being
backstopped by Faber and independent experts
from GTZ. The first few windrows were found to
be suffering a lack of oxygen supply. This was
attributed to inadequate reinforcement and profi-
ling of the biotreatment areas, coupled with
insufficient load-carrying capacity of the base-
course pallets. This gave rise to numerous opti-
mizing measures designed to improve the sup-
ply of oxygen to the heaps. Now the results of
subsequent tests confirm that the decomposi-
tion process is proceeding satisfactorily. The
process adaptation is being monitored by way
of extensive temperature profiling and gas-com-
position measurements.
Initially, the pilot project was supposed to last
one year, but its duration has since been exten-
ded to mid-2003 to allow unequivocal demon-
stration of the effectiveness of the now comple-
ted optimizing measures during the rainy season
too. Completion of the trial-operation phase will
be followed by negotiations regarding continua-
tion of the process and its implementation into
the local waste management system.
4.1.3 Scale-model MBWT trial in
Al-Salamieh, Syria
The organic fraction of waste collected in Al-
Salamieh amounts to approximately 70 %. Al-
Salamieh has an urgent demand for soil amelio-
ration, so people there are very interested in
turning at least part of that fraction into com-
post. The Al-Salamieh model experiment there-
fore included an appraisal of various options for
generating useful compost fractions via mecha-
nical-biological treatment of household and
commercial waste inputs.
19
Figure 8: Mechanical-biological waste treatment usingthe FABER-AMBRA® process in Phitsanulok
Considering the composition of the waste, the
pedological situation and the economic context,
together with the country's dependence on
imported fertilizers, the generation of compost
from waste makes economic sense in Syria, and
is not unknown there. However, since the con-
ventional method of composting the aggregate
waste input had proved unable to yield compost
of the required quality and environmental safety,
a mechanical-biological waste treatment con-
cept was applied in an attempt to stabilize the
residual waste while obtaining a high-quality
compost fraction, and hence reducing the ulti-
mate amounts of waste destined for the landfill.
Unlike other pilot-scale field trials, in which pre -
treatment is intended to improve the disposal
situation, the Al-Salamieh experiment focused
on obtaining a good soil conditioner. The main
objectives of the experiment were:
1. to demonstrate and explain different process-
technological variants for MBWT and compost
production by comparison with currently
employed concepts,
2. to portray the general legal situation regarding
the operation of an MBWT facility and the use of
the subfractions obtained,
3. to analyze and characterize the obtainable
compost fraction,
4. to appraise the market for subfractions ob-
tained,
5. to estimate the anticipated costs of MBWT
enlisting local technologies,
6. to prepare an ecobalance of various disposal
options.
The properties of compost are heavily depen-
dent on both the nature of the inputs and the
composting process. Pretreatment (separate
collection and/or removal of disturbants, un-
wanted materials and - optionally - recyclables,
comminution, etc.) and the composting condi-
tions therefore had to be selected to produce
composts of defined quality for defined purpo-
ses, and to enable sustained achievement of the
requisite quality parameters. For example, diffe-
rent windrows were built up of summer waste
and winter waste, the compositions of which dif-
fer considerably. All in all, approximately 220 Mg
of waste from garbage collection in Al-Salamieh
was employed in the experiment. In addition to
the common-landfill variant as the reference
embodiment, three windrows composed of
mixed, coarsely presorted household waste and
separately collected biowaste were investigated.
The waste was piled up in pressure-ventilated
windrows of trapezoidal cross section. To keep
the windrows from drying out, and in order to
minimize the odor nuisance, the heaps were
covered with a semi-permeable tarpaulin.
Sector Project MBWT - Final Report
20
Figure 9: Composting windrow in Al-Salamieh,with cover and forced ventilation
The experiments demonstrated the suitability of
the procedural approach employed for MBWT
and hence for the production of high-quality
compost. With regard to the quality of the matu-
re compost, the study also illuminated the
importance of either collecting biowaste separa-
tely or subjecting it to a similarly oriented form
of pretreatment.
A large-scale pilot project based on the results
of this model experiment is presently in prepara-
tion for validating and adjusting the process.
The goal is to build and operate an MBWT facili-
ty in Al-Salamieh with a capacity of 15,000 -
20,000 Mg/a. Appropriate technical and politi-
cal-institutional embodiment measures are being
provided to ensure the long-term efficiency of
the MBWT facility. GTZ will help finance and
implement the training and upgrading measures
for the various target groups, the production of
training and reference materials, the promotion
of public awareness, and the provision of con-
tacts in Syria. The firm W. L. Gore will be
responsible for building and operating the waste
treatment plant, for coordinating the various
parts of the system, and for adapting them opti-
mally to the local situation. The entire measure
will enjoy the scientific backstopping of the Uni-
versity of Kassel, Waste Technology Faculty.
4.1.4 Other projects
In addition to the aforementioned projects,
which focus on the field-testing of MBWT, the
sector project also provided support to various
other projects of similar thrust.
Pilot project in Atlacomulco, Mexico
The purpose of this project is to introduce an
integrated, sustainably safe and reliable form of
waste management with integration of the infor-
mal sector. To this end a waste-sector training
and upgrading program is being implemented in
the City of Atlacomulco and its surrounding
communities. The training and upgrading pro-
gram consists of three components:
composting,
sorting of recyclables and management of a
microenterprise (Microempresa),
treatment of waste inputs according to the
MBWT process.
The overall concept envisages the coupling of
composting, recovery of recyclables, and MBWT
(using the FABER-AMBRA® process). The inten-
tion is to implement an ecologically optimized
scheme that will simultaneously make an impor-
tant contribution to poverty reduction. Until now,
most salvaging has been done by the informal
sector (waste pickers = Pepenadores). The com-
posting, recycling and sale of compost and
secondary raw materials will substantially impro-
ve the latter's income situation.
21
Promotion of ecologically sound waste manage-
ment in Colombia
The waste management engineering consultants
Ingenieurbüro für innovative Abfallwirtschaft (ia)
GmbH, in cooperation with B.A.U.M. TRACOM
Ltda, in Bogotá, and with GTZ, have implemen-
ted a pilot project in Armenia (capital of Quindío
Department, Colombia) for introducing an inte-
grated approach to sustainable development via
theory and practical training in the areas of
"integrated waste management" and "sustain-
able waste management". The project objectives
were to establish a technical college and to
plan, build and operate a model MBWT facility
with a practical training mandate.
After sorting and screening, the material is
homogenized in a mixing drum and then com -
posted in bamboo composting bins. The project
also qualified trainers for turning out future spe-
cialists. A further focal point of the project was
to compile the experience gained and make it
available to interested parties across South
America via the internet portal "Foro-Z", the
waste-management knowledge portal for Latin
America" (www.foro-z.com). The project has
been completed, and further cooperation and
the development of additional projects within the
region are planned.
4.2 Results and Experience Gathered
from Pilot Projects
The essential results of the pilot projects are
discussed below, with special attention given to
the projects in São Sebastião, Brazil; Al-Sala-
mieh, Syria; and Phitsanulok, Thailand. These
pilot projects have either already been comple-
ted, or soon will be, and they have yielded volu-
minous data. The pilot projects in Phitsanulok
and São Sebastião come close to normal opera-
tion in terms of their quantitative throughput3
and equipment endowment, so the results are
reliable with regard to costs and the use of
machinery. The model experiment in Al-Sala-
mieh involved relatively small amounts of waste,
so its results do not necessarily apply uncondi-
tionally to normal operation as far as costs and
the use of machinery are concerned. On the
other hand, the model project in Al-Salamieh
enjoyed very intensive scientific backstopping,
and the data yield is accordingly voluminous.
Sector Project MBWT - Final Report
22
Figure 10: Training for Recicladoresat the scale-model MBWT facility inArmenia, Colombia
3 In Sao Sebastiao, all waste arriving at the landfill is now pretreated. In Phitsanulok, approximately 30 % of the waste arriving at the landfill undergoespretreatment in connection with the pilot project.
4.2.1 Project preparation
The pilot projects were based on feasibility stu-
dies in which the local boundary conditions (e.g.
the fundamental waste-management and econo-
mic data) were collected and a project concept
developed. The main objectives of the pilot pro-
jects, which were implemented on the basis of
the aforementioned feasibility studies, were
to verify the assumptions of the feasibility
study and clarify open questions,
to test the process and adapt it to the local
situation as necessary,
to train local personnel and demonstrate the
process and its results in the partner coun-
try, and
to assess the chances and risks of the pro-
cess employed in the project area.
4.2.2 Monitoring programs
4.2.2.1 Basic principles
The time history of the biological process taking
place within the biotreatment heap can be des-
cribed by means of various parameters:
Temperature
The decomposition process liberates energy in
the form of heat, and the temperature increases
in tandem with the activity of the microorga-
nisms. This produces a typical time history of
temperature over the duration of the decompo-
sition process. At the same time, the biological
efficiency of the microorganisms is also a func-
tion of temperature, reaching its peak at appro-
ximately 70°C during the intensive-decomposi-
tion phase.
Continuous monitoring of the temperature
makes it possible to detect deviations from the
optimal decomposition process and to take
appropriate countermeasures to improve the
conditions of decomposition (e.g. ventilation,
moisturizing, turning). The temperatures were
monitored by means of probes (or sampling
gauges) penetrating some 1.5 m into the heap.
The temperatures were measured once a week.
23
Figure 11: A typical decompositiontemperature curve
The experience gained in the pilot projects
shows that it can take several years to progress
from the initial study to normal operation. In
addition to financing matters, there were nume-
rous other causes of delay, e.g. clarification of
customs issues for the importing of equipment,
adaptation of the process technology to local
conditions, clarification of site availability, and
lengthy licensing and decision-making proces-
ses.
70
60
50
40
30
20
10
0
Time history of decomposition temparature
Tem
per
atur
e (°
C)
Time
Inte
nsiv
e d
eco
mp
osi
tion
pha
se
Po
st-d
eco
mp
osi
tion
pha
se
Ter
min
al d
eco
mp
osi
tion
pha
se
Pre
-dec
om
po
sitio
n-p
hase
Gas evolution
Aerobic decomposition is a process in which
oxygen-dependent microorganisms break down
organic substance. The process liberates carbon
dioxide, water and heat, leaving behind a resi-
dual organic mass. If the supply of oxygen is
interrupted, the process turns anaerobic, and
the resultant fermentation becomes recognizable
by the generation of methane. Consequently, by
monitoring the oxygen, carbon dioxide and
methane levels in the heap, the operator can tell
whether or not it is getting enough oxygen, how
well the gases resulting from the biological pro-
cesses are escaping, and whether or not the
aerobic decomposition process is encountering
any problems.
Solids analysis
The processes of organic decomposition taking
place in the biotreatment heaps can be monito-
red by various analytical methods of determining
such factors as the total organic carbon content
of the waste (TOC) , its gas formation rate
(GB21) and its dynamic respiration activity level
(AT4).
4.2.2.2 Implementation via pilot projects
Prior to starting the pilot projects, a monitoring
program was elaborated in collaboration with
the various actors. In São Sebastião and Phits-
anulok, monitoring and evaluation were carried
out by both Faber and independent experts
acting on behalf of GTZ. In Syria, the University
of Kassel, Waste Technology Faculty, provided
scientific back-stopping for the project.
Sector Project MBWT - Final Report
24
Table 3: Proposed monitoring program for thepilot-scale field trial in Phitsanulok
Frequency Meas. point
Input
Visual inspection -
Temperature in the heap -
Moisture in the heap -
Height
-
Ambient temperature -
Precipitation -
-
Gaseous emissions -
Carbon dioxide -
Oxygen -
Nitrogen -
Methane -
-
Water content (solids)
Ignition loss (solids)
TOC (solids) ( )
TOC (eluate)
Respiration activity (AT 4)
Dayly Weekly Monthly Quar-terly
( )
Output On Site Lab
Gas format. rate (GB21)
pH
COD (eluate)
BOD5
AbfAblV criteria*
Density/water content
-
Process water -
Quantity
Conductivity -
pH -
NH4, NO3, TKN -
BOD5 -
COD -
* German directive governing the ecologically viable disposal of municipal solid waste
In addition, numerous other data of importance
for evaluating the process and for further plan-
ning purposes were collected, e.g.:
mass/bulk and volume analyses
process water quantification
equipment operation and downtime
personnel working hours
operational resource requirements
The results of the pilot projects show that the
locally available resources do not suffice for
conducting the tests that are necessary for
assessing the progress and results of the
decomposition process. The specific standards
and facilities required for the performance of
waste analyses are largely lacking in the coun-
tries in question. The analysis of solid waste, for
example, is very complicated and can only be
performed by specialized laboratories. Conse-
quently, most of the pretreated waste from the
pilot projects was analyzed in Germany.
4.2.3 MBWT processes employed in the
pilot projects
Many different MBWT processes have been
developed in Germany in recent years. However,
most of them are oriented to the requirements of
German and European markets and standards,
while some additional criteria have to be consi-
dered for applications in developing countries.
25
The most important data were published in the
experts' reports and can be accessed, inter
alia, via the GTZ MBWT website
www.gtz.de/MBA/English/index.html.
Figure 12: Temperature monitoringwith a sampling gauge in Phitsanulok
4 An overview of processes and providers can be found in [2] and [3].
4.2.3.1 Technology selection criteria
Experience shows that caution is of the essence
for transferring waste treatment technologies
from Germany to developing and threshold
countries. In the past, imported technologies
have often worked well only as long as they had
the benefit of external technical support. There
are various reasons for this, and they apply not
only to financial aspects, but to legal, organiza-
tional and cultural factors as well. First of all, the
basic tenets of development cooperation in the
area of waste management - such as those des-
cribed in the BMZ sector concept for waste
management [4] - must be adhered to. For
example, technologies must be selected in con-
sideration of the fact that, for many people in
many countries, waste-picking is the sole avai-
lable means of making a livelihood.
Hence as far as possible, MBWT projects should
be implemented in a manner to promote better
working conditions for these people, and not to
rob them of their basis of subsistence. Another
essential criterion is that the technology employ-
ed must be affordable. This requirement sub-
stantially diminishes the range of potential pro-
cesses. In Phitsanulok, for example, the charac-
teristics of the waste (high water content, little
structural material, large share of waste in pla-
stic bags) made it appear expedient to employ a
rather complex process technology (e.g. inclu-
ding fermentation of residual waste). On the
other hand, the boundary conditions still prevai-
ling in Phitsanulok made it unlikely that such a
costly approach would be successful with
regard to the financial and technological sustai-
nability of waste management. Consequently,
the only technologies with a potential for suc-
cess were those that would allow the targeted
waste treatment objectives to be achieved with
the lowest possible initial investment and
operating costs,
the lowest possible, locally feasible mainte-
nance and repair expenditures,
the most lenient possible operating require-
ments.
The processes employed in the pilot projects
largely satisfy the aforementioned criteria. It was
also possible to enlist the assistance of German
enterprises and institutions for implementing the
pilot projects. This is not to say, of course, that
none of the other MBWT technologies that were
not field-tested within the scope of the sector
project would be suitable for application in
developing countries.
Sector Project MBWT - Final Report
26
Figure 13: Waste pickers at the Phitsanulok landfill
4.2.3.2 The Al-Salamieh scale-model trial
The following approach to mechanical-biological
treatment and composting of inputs amounting
to 15,000 Mg/a was developed on the basis of
the scale-model trial:
Input
At first, the waste is collected in the normal
manner (mixed collection) and delivered to the
waste treatment site. Eventually the biowaste is
to be collected separately.
Waste comminution
For successful biological treatment, the collec-
ted waste first has to be removed from the pla-
stic bags. To this end a special comminutor
(homogenizing drum), which is to be built in
Syria, is needed to rip open the bags in such a
manner that the recyclables are not rendered
useless or irretrievable by excessively destructi-
ve handling.
Sorting
After the bags are ripped open, the recyclables
and the disruptive materials (disturbants and
unwanted materials) have to be sorted out by
hand. Judging by the waste composition already
ascertained, it should be possible to recover
approximately 150 Mg of scrap metal and 100
Mg of used glass per year as secondary raw
materials. That corresponds to roughly 1 % of
the total input. Theoretically, this would yield
revenues amounting to some PS 1 million
(approx. EUR 20,000) per annum.
Piling and operation of the compost heaps
Following mechanical conditioning, the material
to be composted is piled into heaps with the aid
of a wheel loader. Suitably reinforced (concreted)
composting areas with integrated ventilating
ducts (possibly in the form of channels in the
concrete to accommodate flexible vent pipes
and to drain off the resultant press water and
leachate) are needed to set up the heaps. The
finished heaps are then covered with a semi-
permeable tarpaulin and pressure-ventilated.
Compost recovery
At the end of a 14-week composting process
the material is comminuted once again and
screened to a size of 20 mm. Here, too, a wheel
loader (or a grab excavator) is needed for fee-
ding the compost into the appropriate comminu-
tors.
Landfilling
The oversized material is dumped at the landfill.
Removal of the recyclables, in combination with
the decomposition of organic substance, redu-
ces the volume and weight of the original waste.
This saves space at the landfill and is therefore
highly desirable.
27
Figure 14: Compost heaps during the model experiment in Al-Salamieh
4.2.3.3 The FABER-AMBRA® process in
São Sebastião and Phitsanulok
The individual steps of the patent-protected
FABER-AMBRA® process, which is essentially
based on the natural-draft, chimney-effect pro-
cess developed in Germany, are explained
below.
Coarse sorting
The first step is to remove from the incoming
waste any bulky objects that could cause dama-
ge to the homogenizing drum. Recyclables can
also be sorted out at the same time.
Homogenizing
Further mechanical conditioning of the waste
takes place in a mobile homogenizing drum that
Faber built especially for this purpose.
This step is a crucial element of the process, as
it fulfills the following functions:
Homogenization of the waste introduced
by the wheel loader:
The agitation caused by the turning of the
drum mixes, i.e. homogenizes, the waste.
Good mixing requires some 30 to 45 minu-
tes.
Tearing open of the garbage bags:
As the drum turns, teeth on the inside tear
open the bags of garbage, some of which is
wrapped in two or more bags. A comparison
of freshly arrived waste with the results of
homogenization shows that this approach
worked well in the pilot projects, with only a
small number of garbage bags either not
torn open or only insufficiently so.
Moisturizing the waste:
Water can be added to the waste during the
homogenization process to give it the right
moisture content for the biological proces-
ses. The required amount of water depends
on the nature of the waste inputs. In Phit-
sanulok, it was not necessary to add any
water at all.
Transfer of the waste to the composting
area: After homogenization, the waste is
transferred to the biotreatment area while
still in the drum.
Building the heaps
The truck carrying the homogenizing drum
dumps the homogenized and, as necessary,
moistened waste in front of the pallet-covered
heap-building area by turning the drum back-
wards. A backhoe-equipped hydraulic excavator
picks up the waste and forms it into biotreat-
ment heaps on top of the pallets.
Sector Project MBWT - Final Report
28
Figure 15: Homogenizing drum at work in Phitsanulok
The vent pipes are laid out approximately 4 m
apart. The heaps are piled between 1.80 and
2.50 m high5, depending on the nature and
structure of the waste. Regarding the space
requirement for the heaps, roughly 1 m² per ton
of waste input can be taken as a rule of thumb
for calculation purposes. If the heaps are torn
down before the scheduled end of biological tre-
atment, the organic fraction will not have time to
undergo full biological decomposition.
Covering the heaps
The completed heaps are covered with a layer
of biofiltering material. In Germany, the biofilter
is obtained by screening the pretreated waste.
That, however, necessitates the use of a corre-
spondingly powerful screening unit, but no such
unit was available for the pilot projects. Alterna-
tively, wood scraps (eucalyptus bark) are used
in São Sebastião and coconut shells in Phit-
sanulok. Covering the heaps serves the
following purposes:
uniform heat-soaking of the heaps thanks to
the insulating effect of the cover,
reduction of odors escaping from the heaps
with the vented air,
achievement of a more uniform distribution
of moisture,
partial decomposition of organic carbon
compounds in the biofilter,
better optical appearance of the compost
heaps,
provision of a vermin barrier.
The hydraulic excavator is used to cover the
heap with a 20 - 40 cm-thick layer of biofiltering
material.
29
Figure 16: Waste from Phitsanulokbefore and after homogenization
Figure 17: Piling the waste for biologi-cal treatment in Atlacomulco, Mexico
5 Both in Phitsanulok and in Sao Sebastiao, the heap heights were reduced to improve the supply of oxygen.
Tearing down the heaps
At the end of the biological treatment phase, a
mobile excavator is used to tear down, i.e. to
disassemble, the heaps. In removing the materi-
al, care is taken to preserve as many of the pal-
lets and vent pipes as possible for reuse.
Emplacement of pretreated waste
The residual waste is loaded onto a truck and
dumped at the landfill. If available, a compactor
is used to place the material. If not, a traxcava-
tor or bulldozer will do the job. Optimal landfil-
ling requires that the waste be placed in very
compact thin layers (= onion skin tipping).
4.2.3.4 Evaluation of the technologies
employed
FABER-AMBRA® process
Both in São Sebastião and in Phitsanulok, the
pilot projects confirmed that extensive stabiliza-
tion of pretreated waste can be achieved with
simple equipment and comparatively low initial
investment and operating costs by adopting the
FABER-AMBRA® process. Not only did the
FABER-AMBRA® process work well in the pilot
projects, it was also retained for normal opera-
tion in São Sebastião, where MBWT has since
radically improved the situation at the landfill.
Nevertheless, some aspects still require further
clarification and development:
Sensitivity to high rates of precipitation
The uncovered heaps were found to react
more or less sensitively to high rates of pre-
cipitation, depending on the nature of the
waste. This could even progress to the point
that anaerobic processes begin to take pla-
ce within the heaps (cf. Chapter 4.2.5.2).
Faber is presently investigating various ways
to minimize the effects of weather conditions
by way of reasonable technical and financial
inputs.
Pallets
In Phitsanulok, the quality and physical cha-
racteristics of the pallets proved to have a
decisive impact on the decomposition pro-
cess. In Thailand, suitable pallets are com-
paratively expensive and often serve as
secondary raw material for other purposes.
Consequently, various alternatives to the use
of such wooden pallets should be investiga-
ted.
Biofilter
Various materials were used for making bio-
filters in the pilot projects. The coconut
shells used in Phitsanulok are waste pro-
ducts and available free of cost. Conversely,
the eucalyptus bark used in São Sebastião
is comparatively expensive and could be put
to other uses. It would therefore be advisa-
ble to investigate some alternative biofilter
materials.
Homogenizing drum
The rotary drum vehicles used by Faber
were imported from Germany. The homoge-
nizing drum is the most technically elaborate
part of the FABER-AMBRA® process and
not yet available in the project countries.
However, the drum is needed to make the
input material suitable for biological treat-
ment. Its operation requires qualified per-
sonnel and regular maintenance, because
replacement vehicles are very expensive and
difficult to obtain. Hence efforts should be
made to develop locally available, more
inexpensive alternatives.
Gas monitoring
Monitoring the generation of gas with a
handheld measuring instrument has proved
rather unreliable. Some simple but reliable,
locally appropriate method of gas measure-
ment needs to be developed.
Sector Project MBWT - Final Report
30
Al-Salamieh
The process concept also worked well in Al-
Salamieh. The decomposition process and its
results are in line with expectations. Covering
the heaps with an air-permeable membrane
made it possible to dispense with supplemen-
tary moisturizing of the heaps. While this does
make the process somewhat more complex
than the FABER-AMBRA® process, it also offers
advantages for applications in arid climates as
well as in areas with abundant precipitation. In
Al-Salamieh it is planned to integrate the field-
tested process into normal operation. However,
the requisite equipment will have to be locally
redesigned.
Provision of special-purpose equipment for
waste treatment
No special waste-treatment equipment - waste
comminutors, homogenizing drums, screeners,
etc. - is to be found in any of the project coun-
tries. That, of course, means that such equip-
ment either has to be imported or fabricated
locally as one-off items. For imported equip-
ment, proper maintenance and spare-parts pro-
curement must be assured for the long term,
and any locally fabricated equipment has to
meet certain quality standards with regard to
corrosion resistance, mechanical strength, etc.
Within the scope of the pilot projects it was not
possible to determine the extent to which local
fabrication of low-cost equipment meeting these
quality standards could actually be realized.
In Syria, the comminutors and screeners have
also been earmarked for local fabrication and
integration into normal operations. Inquiries
among local contractors indicate that fabrication
of the equipment in Syria would cost some
90 % less than it would to import the items from
Germany. Whether or not these price estimates
would hold true in actual practice, and the
extent to which the finished items of equipment
actually meet the set requirements, remains to
be seen. In Brazil, options for local manufacture
of a homogenizing drum are being explored.
4.2.4 Operation of an MBWT facility
Extensive MBWT processes are characterized
by the use of "simple" technology. However, that
does not mean that such processes are "simple"
to control. On the contrary. It is probably more
difficult to create optimal conditions for the bio-
logical degradation of organic material in an
uncomplicated, extensive process than it would
be in a more intricate, intensive one. For exam-
ple, in any country where composting and other
comparable techniques are not widely dissemi-
nated, it takes time to build up the requisite
know-how. Hence one major constituent of all
pilot projects was to provide training for the
local personnel.
31
4.2.4.1 MBWT personnel requirements
For an MBWT process to achieve good results,
it must be managed with due competence and
commitment. In addition to normal managerial
and leadership skills, the operator must also
have the experience needed to optimally control
a biological decomposition process. The per-
sonnel needed for the other work must have
qualifications comparable to those of civil-
engineering workers (e.g. shovel men, truck dri-
vers, mechanics).
4.2.4.2 Training
Both in São Sebastião and in Phitsanulok, Faber
not only provided technical support for the
MBWT facility, but also trained the local workfor-
ce. During the first months of the project, Faber
personnel were in constant attendance. That
was also the time frame of the intensive training
phase for the workers. In both pilot projects, the
per-sonnel were hired by the municipal authori-
ties. Their theory-based training encompassed
explanations of the mechanical and biological
steps of the process and of the various machi-
nes, but their actual practical training took place
directly at the landfill with the MBWT in opera-
tion. The engineers and political decisionmakers
involved were invited to attend information
workshops and seminars covering both the
theoretical and practical fundamentals and
objectives of the MBWT process.
Thereafter, Faber's backstopping inputs were
gradually reduced from month to month, while
the local employees just as gradually assumed
responsibility for operating the MBWT facility. All
the while, Faber operatives remained on call to
help the local personnel and ensure that opera-
tional safety and reliability was maintained.
Sector Project MBWT - Final Report
32
Personnel requirementJob scope
Main season (4 months)
Off season (8 months)
Technical management 2 1
Machine operators (excavator,wheel loader, drum, truck)
10 5
Laborers 6 4
Total 18 10
Project phase Duration Work inputs by Faber Recycling
Introduction and training 1 month uninterruptedly from May 8 - June 2, 2000
1st backstopping phase 2 months twice weekly, June 5 - Aug. 4
2nd backstopping phase 3 months once weekly, Aug. 7 - Nov. 3
3rd backstopping phase 6 months twice monthly, Nov. 6 - Apr. 30, 2001
Table 4: Personnel requirements for MBWT opera-tions in São Sebastião (throughput: 30,000 Mg/a)
Table 5: Backstopping work scope for Faberduring the one-year implementation phase in
São Sebastião
Figure 18: Training fortechnical personnel at the
Phitsanulok landfill
4.2.4.3 Integration into the organizational
structures
In developing and threshold countries, it is rat-
her an exception to the rule to encounter well-
qualified, well-motivated personnel working at
landfills. Consequently, it is not only necessary
to teach the local staff how to operate the
MBWT facility, it is also necessary to establish
better-paying job slots for better-qualified per-
sonnel.
On the administrative side, the prerequisites for
effective, controlled operation of the landfills and
MBWT facilities must be established. This inclu-
des on the one hand proper organization of the
operation (responsibilities, assignments, material
procurement, budgeting), and on the other hand
performance control.
The findings show that the existing structures
and the available personnel suffice only for low-
quality operation of MBWT facilities. Numerous
problems were encountered, including frequent
cases of people not showing up for work, orga-
nizational deficits (lack of pallets or other resour-
ces), defective vehicles, and the pulling of per-
sonnel for other assignments. Both in São Seba-
stião and in Phitsanulok, the early phase of ope-
ration therefore achieved only 30 - 40 % of the
theoretically possible throughput.
33
September October
Date 25 26 27 28 29 30 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18
Day of week W T F S S M T W T F S S M T W T F S S M T W T F
Wheel loader*
Excavator*
Rotary drum*
Veh. operator**
Laborer**
*defective Machine ** absent personnel half day full day
60
50
40
30
20
10
0
MBWT capacity utilization rates and causes of outage in Phitsanulok, Thailand
Tre
ated
was
te [M
g/d
]
Figure 19: Theoretically achievable and actu-al throughput at the MBWT facility of the
Phitsanulok pilot project
planned target throughput
Considering the given structures and the organi-
zational problems encountered in São Sebastião
and Phitsanulok, further operation of the MBWT
facility by the local staff with no outside help fol-
lowing completion of the pilot phase would have
been inconceivable.
In the meantime, operation of the MBWT facility
and landfill in São Sebastião has been priva-
tized. Faber has contracted to provide all the
requisite special-purpose operating equipment
and to remain available for providing follow-up
assistance and controlling functions. Privatiza-
tion has had positive effects on the MBWT facili-
ty's operation, because the economic incentive
gives the operator more reason to be interested
in efficiency than the previous municipal
employees were. The workers are at home in
their jobs now and appear to be very well moti-
vated. Indeed, the clear-cut allocation of respon-
sibilities and the designation of supervisory per-
sonnel have significantly improved the operatio-
nal organization. Impediments such as a lack of
operational resources or having the city's landfill
personnel fail to show up for work due to orga-
nizational or motivational problems no longer
occur. Moreover, the manager of the operating
company has professed an interest in introdu-
cing MBWT for other waste projects as well.
This concept appears to be ensuring the suc-
cess of MBWT's sustainable implementation in
São Sebastião.
4.2.5 Chronology and results of aerobic
decomposition
Biological decomposition of the organic con-
tents of the waste input is the central step of the
MBWT process. Since there is no way to control
the processes of decomposition directly in the
course of aerobic waste treatment, various para-
meters are used to describe its progress (cf.
Chapter 4.2.2). The results of aerobic decompo-
sition in the pilot projects are discussed below
on the basis of these parameters.
4.2.5.1 Time history of in-heap
temperatures
In all pilot projects, the temperature inside the
heap was continuously monitored at various
points. During the most intensive phase of orga-
nic decomposition, the in-heap temperature
should be situated between 55°C and 70°C. If
the temperature drops below 50°C for any con-
siderable length of time during the first phase of
decomposition, something is probably slowing
down or disrupting the processes of decay. Low
temperatures during the initial phase may also
indicate excessive moisture (and the possible
resultant occurrence of anaerobic processes).
As time passes, the in-heap temperature gradu-
ally declines, as shown in the following diagram,
which exemplifies the time history of temperatu-
re in all decomposing heaps of the Al-Salamieh
field test in Syria.
Sector Project MBWT - Final Report
34
Most of the temperatures measured are situated
within the indicated spectra, which neatly match
the ideal temperature curve shown in Chapter
4.2.2.1 for the biological decomposition proces-
ses. The rapid increase in temperature during
the first two weeks is quite conspicuous. This
most intensive phase of the process lasts as
long as approx. 40 days, while the subsequent
post-decomposition phase lasts considerably
longer. Remarkably, the first and second turn-
ings of the heaps produce no distinct rise in
temperature.
The temperature curves obtained for FABER-
AMBRA® heaps differ from those tested in Syria
by reason of their longer decomposing times
and passive aeration. In a FABER-AMBRA®
heap the temperature rises quickly at the begin-
ning of the process and then remains between
55°C and 70°C for approximately five months,
after which it slowly declines.
35
Time history of temperatures in all heaps as a function of decomposing time, in Al-Salamieh, Syria
Tem
per
atur
e (°
C)
0 10 20 30 40 50 60 70 80 90 100
Time (days)
80
70
60
50
40
30
20
10
0
1st turning 2nd turning 3rd turning
90
80
70
60
50
40
30
20
10
0
Time history of in-heap temperaturesin Sao Sebastiao, Brazil
Tem
per
atur
e (°
C)
Jan Feb Mar April May Juni Juli Aug Sep Oct Nov
2001
T1 T2 T3 Umgebung
Figure 20: Time history of in-heap temperatures in the Al-Salamieh scale-model trial
Figure 21: Time history of in-heap temperatures in São Sebastião
4.2.5.2 Effects of rainy season on
the temperature curve
The temperature readings taken in Phitsanulok
show that heavy precipitation of the kind that
often occurs during the rainy season there has
definite impacts on the heat balance of the
heaps.
The in-heap temperature is seen to drop precipi-
tously with the onset of heavy rains in early Sep-
tember, while the light rains before that time had
no detectable effect on the temperature. Begin-
ning around mid-September, the temperature
rises slowly but surely until more heavy rains in
late October again quench the heap. After that,
the temperature recovers again, rising to bet-
ween 55°C and 60°C, which corresponds well to
the age of the heap. During the month of Oct-
ober, samples were taken from the heaps for
use as specimens in determining the heaps' bio-
logical efficiency. The samples display high moi-
sture contents ranging between 55 % by weight
and 62 % by weight. Various ways and means
of keeping the heaps from becoming waterlog-
ged were considered and developed:
put less water in the homogenizing drum
ensure good off-flow of process water from
the heaps by paving the biotreatment area
and providing adequate slope (at least 3 %)
choose the pallets for the ventilating course
with care as regards quality and durability
reduce the height of the heaps
apply a thicker layer of biofilter material
The use of different geotextiles for covering the
heaps during the rainy season is presently being
investigated.
Sector Project MBWT - Final Report
36
80
70
60
50
40
30
20
JUNI JULI AUG OCT NOV DEC JAN
300
250
200
150
100
50
0
Time history of temperatures in heap C, measuring point 2 Beginning of decomposition process: May 17, 2002
incl. weekly precipitation yields and ambient temperature
Tem
per
atur
e (°
C)
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33
Process duration [weeks]
Precipitation Temp. 2s, 0,8m
Temp. 2l, 1,2m Temp. Air
Pre
cip
itatio
n (m
m/w
eek)
Figure 22: Time history of temperatures in a FABER-AMBRA® heap exposed to heavy precipitation
4.2.5.3 Gas composition
The composition of the biogas that is being
generated within the heap can provide informa-
tion on the quality of the composting process
and on any disturbances which may be affecting
it. First of all, aerobic decomposition is highly
dependent on an adequate supply of atmos-
pheric oxygen. In an ideal case, the oxygen con-
centration within the heap should amount to at
least 10 % by volume. As the microorganisms
digest the organic matter, they respire oxygen
into carbon dioxide. Accordingly, the CO2 con-
centration within the heap increases markedly
and may even reach levels of the order of 10 %
by volume. Methane is an indicator of anaerobic
decomposition processes and has been identi-
fied as a climaterelevant gas. In a well-functio-
ning windrow, the methane concentration should
remain at roughly 1 % by volume most of the
time, though short-lived higher concentrations
may occasionally occur.
If the oxygen concentration drops below the
aforementioned 10 % by volume, and if the CO2concentration rises significantly above 10 % by
volume at the same time, either the heap is not
getting enough fresh air, or the off-gas is not
escaping as well as it should. If the methane
concentration is also higher than normal for any
considerable length of time, the aerobic decom-
position processes are apparently disturbed.
The following illustration visualizes the relation-
ship between oxygen content and CO 2 concen-
tration in the light of selected readings from
Phitsanulok.
37
25
20
15
10
5
0
Relationship between oxygen content and carbon dioxide concentration Case in point: Phitsanulok, Thailand
Gas
co
ncen
trat
ion
[vo
l.%]
O2, MP 1 CO2, MP 1
O2, MP 2 CO2, MP 2
0 5 10 15 20 25
Biological treatment time [weeks]
Figure 23: Relationship between oxygen content and carbon dioxide concentration
The diagram clearly shows how any increase in
the CO2 concentration is accompanied by a
corresponding decrease in the oxygen concen-
tration. Whenever the O2 concentration drops
below 5 % by volume, the CO2 level increases
markedly. Conversely, the CO2 level drops
below 5 % by volume as soon as the oxygen
content rises above 15 % by volume.
In the Phitsanulok pilot project, the gas compo-
sition within the heaps was monitored via an
extensive series of measurements. The parame-
ters of interest were oxygen, carbon dioxide and
methane. The readings were obtained via sam-
pling gauges installed at various points in the
heaps. The samples were drawn with the aid of
a vacuum tube and analyzed at the Asian Insti-
tute of Technology (AIT) in Bangkok. The fin-
dings were disparate. The first heaps showed
high methane concentrations (> 20 % by volu-
me) in combination with low oxygen levels
(< 5 % by volume) and relatively high carbon
dioxide levels. This was taken as an indication
of an-aerobic activity within the heap promoted
by a lack of oxygen. Most of the methane con-
centration readings correlated well with high
CO2 levels. The methane concentration hardly
ever rose above 10 % by volume if the oxygen
concentration was 10 % by volume or higher.
The third heap (heap C), which was situated on
an adequately sloped part of the old landfill,
displayed fewer high methane concentrations,
al-though some of the individual readings were
higher than 25 % by volume. There was a
remarkable, continuous increase in methane
concentration over time, and this was under-
stood as an indication of insufficient oxygen.
While the methane concentration never ex-
ceeded 10 % by volume during the first three
months, some monitoring points documented a
distinct rise in methane levels after about the
16th week of the composting process.
Visual inspection of the heaps revealed that the
points in question were very wet and fairly
blackened. These were points at which the pal-
lets had broken, and the bottoms of the heaps
were standing in water.
Data for the first five months of biological treat-
ment are available for the first of the heaps to be
set up in the designated waste treatment area
(heap D). Since less data were collected from
heap D than from heap C, no definite conclu-
sions can be drawn. However, it was noted that
the methane concentration increased during the
12th through 14th weeks of treatment and then
returned to levels below 10 % by volume by the
time of the last reading. An inspection of those
points once again disclosed that the pallets for-
ming the ventilating course had broken. Conse-
quently, pallets of higher quality are now being
used, and the new heaps are producing much
less methane. The lesson to be learned here is
that a well-prepared biotreatment area and care -
fully placed ventilating courses are two crucial
factors for the stability of the decomposition
process, and the results of their optimization will
be the subject of continued monitoring to valida-
te the observed developments.
Sector Project MBWT - Final Report
38
Figure 24: Waterlogged base of a heap showingevidence of anaerobic decomposition
The relevant evolution of methane may be attri-
butable to any of the following factors:
During the rainy season, the high initial
moisture level coupled with heavy precipi-
tation causes partial waterlogging of the
heap and, hence, formation of anaerobic
zones.
Sloppily installed, perhaps already broken,
pallets of poor quality allow waste to block
off the ventilating course and interrupt the
supply of air.
If the ground is not adequately reinforced
and becomes muddied by process water
and rainwater, the pallets will sink in and cut
off the supply of air.
If the waste contains a large share of plastic
bags and not much structural material, both
the air supply and the drainage of water can
be impeded at various points.
In Brazil, too, elevated methane concentrations
were noted at the beginning of the decomposi-
tion process. However, this was attributed to
methane emissions from the old landfill, on top
of which the heaps were standing. In the further
course of process implementation, there were
no more indications of elevated methane con-
centrations (odor, visual inspection, ...).
In Syria, oxygen concentration readings indica-
ted that the inferior structural properties of the
waste might cause a shortage of oxygen. To
verify this, the plastic bags were removed from
some of the waste, and the heaps' oxygen-sup-
ply situation was seen to improve substantially.
It was also recommended that extra structural
material be mixed into the waste in order to
promote better aeration.
39
20
18
16
14
12
10
8
6
4
2
0
Composition of gas in heaps C and D in Phitsanulok, ThailandSamples drawn Feb. 13, 2003
Gas
co
ncen
trat
ion
[vo
l.%]
O2 CO2 CH4
C2 C3 C4 C5 D1 D2 D3 D4 D5
Heap on old landfill Reinforced composting area with adequate
slope and pallet checks
Figure 25: Results of gas monitoring at heaps C and Don February 13, 2003, in Phitsanulok
4.2.5.4 Water content
The water balance of the heaps is also an
important criterion for optimal decomposition.
On the one hand, the microorganisms need
water for their metabolic processes, but on the
other hand high water contents promote the for-
mation of anaerobic cells as soon as the excess
water cannot be drained out of the heap. Hence
for the duration of the decomposition process,
the water content must be maintained within a
range that is amenable to aerobic decomposi-
tion. Consequently outdoor heaps have to be
watered during dry periods, but process water
can dribble out of the heaps during periods of
heavy rainfall. (The reader is referred to Chapter
4.2.6.4 with regard to the incidence and compo-
sition of process water.)
In Germany, initial water contents of 40 - 55
wt.% are regarded as favorable for extensive
decomposition processes. The water-retaining
capacity of the waste material is a relevant para-
meter. Since the starting material normally con-
tains relatively little water, an appropriate
amount is added at the beginning of biological
treatment. In the pilot project, however, the star-
ting material contained more water, because it
consisted largely of organic substances.
In Al-Salamieh, some 70 % to 80 % of the water
content of the input material is eventually lost to
evaporation and other factors. The Phitsanulok
trial showed water losses totaling approximately
50 %. (The reader is referred to Chapter 4.2.7.2
with regard to the mass balance.)
4.2.5.5 Solids and eluate analyses
Evaluating the biological efficiency of the
decomposition process necessitates an analysis
of the residual solids and eluate in the digested
material. This includes determining its total orga-
nic content (TOC) and its biological activity
(dynamic respiration activity level, AT 4, and gas
formation rate, GB21) in order to characterize
the remaining active organic substance. Analysis
of the pollutants, e.g. of heavy metals and or-
ganochlorine compounds in the eluate from the
solids, can provide information on the remaining
pollutant inventory, and hence on how much
pollution could result from emplacement of the
decomposed material.
The pilot project included various analyses of
solids and eluates. The following table compares
the results of the FABER-AMBRA® process in
Brazil after six months and after nine months of
biotreatment with the correlative values stated in
Germany's waste disposal directive on mechani-
cal-biological waste treatment facilities (AbfAblV,
App. 2), which must be adhered to in Germany
for proper landfilling of such material.
Sector Project MBWT - Final Report
40
Pilot project Water content [wt.%]
São Sebastião, Brazil > 60%
Phitsanulok, Thailand approx. 65%
Al-Salamieh, Syria 54% - 59%Table 6: Water content of waste inputs in the pilot projects
The results show that six months suffice for
most of the organic substance to decompose,
and that after nine months, the requirements of
Germany's waste disposal directive are reliably
satisfied. While some initial data on the results
of decomposition have been gathered in Phit-
sanulok, the findings indicate that the biological
activity can be expected to decline significantly
in the course of the process. Biotreatment-out-
put analyses are under way.
4.2.5.6 Results of composting trials in
Al-Salamieh, Syria
The Al-Salamieh field trials included broad-scale
tests and investigations on the treatment of
various input materials. In addition to the
mechanical-biological treatment of waste inputs,
the trials were also intended to investigate the
suitability of the process for producing market-
able compost. Both pure household waste and
separately collected and sorted biowaste were
test-composted.
The course of the various composting trials and
the quality of their outputs were characterized
on the basis of numerous tests and analyses,
the results of which show that a composting
time of 14 weeks is sufficient to obtain adequa-
tely mature finished compost. Even after a mere
6 to 8 weeks, the process reaches the maturity
of fresh compost.
41
Solids analysis Sample of 6-month-old comp.
Ignition loss [wt. % TS] 23,8
TOC [wt. % TS] 9,6
Respiration activity (AT4) [mg/kg TS] 5,4
Gas formation potential (GB21) [Nl/kgTS]
Eluate analysis
pH [-]
Electr. conductivity [µS/cm]
TOC [mg/l]
Ammonium-N [mg/l]
732
158
< 1,0
28,5
7,3
Sample of 9-month-old comp.
27,7
12,2
2,6
785
92
< 1,0
12
7,1
Correlation value(AbfAblV*, App. 2)
-
< 18
< 5
< 50.000
<250
< 200
< 20
5,5 - 13
COD [mg/l] 270
BOD5 [mg/l] 5
300
6
-
-
Table 7: Results of treated-waste analysis in São Sebastião 6
6 The laboratory analyses were conducted by the Leichtweiss Institute for Hydraulic Engineering at the Technical University of Braunschweig.
The findings in São Sebastião lead to the con-
clusion that a nine-month period of biological
treatment stabilizes the input material to such
an extent, that subsequent landfilling of the
residual waste would produce low emissions.
The compost substrates obtained via the
various forms of treatment all display good qua-
lity in terms of such value-defining physical and
chemical parameters as their nutrient contents,
salinity, pH and total organic content. However,
the benefits of collecting biowaste separately
are reflected by the significantly lower heavy
metal contents of the output.
In addition to documenting the suitability of the
process approach applied for mechanical-biolo-
gical waste treatment and obtaining high-quality
compost, the results also illuminate the benefits,
with respect to the quality of the finished com -
post, of either collecting biowaste separately or
pretreating the waste in a manner to achieve
similar results. Accordingly, the separate collec-
tion of biowaste would provide much-improved
conditions for an effective, more inexpensive
form of waste aftercare. However, the separate
collection of good-quality biowaste would most
likely have to be implemented on a step-by-step
basis and be correspondingly expensive.
Sector Project MBWT - Final Report
42
Table 8: Heavy-metal contents as a function of input material
mg/kgLead 117 105 114 122 118 117 150 120 150
mg/kgCadmium 0,1 0,1 0,1 0,2 0,1 0,1 1,5 3 5
mg/kgChromium - - - - - - 100 100 150
mg/kgCopper 96 82 90 87 72 65 100 150 250
mg/kgNickel 56 53 32 34 49 26 50 50 70
mg/kgMercury 2,3 2,1 1,90 1,90 2,10 0,89 1,00 1,50 3,00
mg/kgZinc 456 446 201 214 324 159 400 350
Compost samples
Separatebiowastecollection
Bundesgü-tegemein-
schaft*
Syrian
Uncomminuted hou-sehold waste
Sorted-out biowaste Comminu-ted house-hold waste Q. cat. 1 Q. cat. 2
500
in transgression of German targets* Targets of the German quality-compost association Bundesgütegemeinschaft Kompost e.V.
4.2.6 Emissions from MBWT
In Germany, very ambitious emission standards
have already been established for MBWT. In
most developing countries, though, it would not
be possible to meet similar targets quickly. The
waste disposal situation there can only be
improved gradually and in due time. Thus the
benchmark criterion for evaluating the emission
situation in the pilot projects is how much
improvement can be or has been achieved by
comparison with the initial waste-disposal situa-
tion.
4.2.6.1 Basic principles
The very nature and composition of waste per
se means that all forms of waste treatment will
inherently involve some sort of emissions, the
nature and extent of which will depend very
strongly on the chosen approach and the local
boundary conditions. The most important
MBWT emissions are listed below together with
various means of controlling them:
Leachate
Waste treatment produces process water, so
the biotreatment areas should be reinforced,
and the process water from biological treat-
ment needs to be collected and used for
watering the heaps, appropriately treated, or
disposed of. To the extent that an existing
landfill is equipped for leachate collection, it
may be expedient to put up the heaps for
simple biological treatment directly on top of
the landfill.
Odors, germs
The odor and gas emissions from simple
biotreatment heaps can be controlled by
covering the heaps with a course of screen-
ed, treated waste. Handling of the waste
releases germs into the environment, and
this can pose a health risk for the people
working at the landfill, though it has no
effect on areas situated further away.
Vermin
Table scraps and the like contained in hou-
sehold waste attract many different kinds of
animals that can contribute to the spread of
diseases and constitute a nuisance to local
residents. For simple processes, covering
the heaps is an effective means of keeping
animals away.
Noise
Comminutors, screeners, conveying and
ventilating equipment, etc. can be very noi-
sy, and both the operating personnel and
nearby residents are most strongly affected.
At a distance of 500 m or more, the noise
generated by MBWT equipment is not loud
enough to cause annoyance.
Another way to limit emissions is to take the
waste treatment operations indoors, where the
leachate and waste inputs can be collected and
treated in a manner to preclude most emissions.
However, this makes the facility correspondingly
more complicated and expensive in terms of
structures and machinery.
43
4.2.6.2 Odors
None of the pilot projects included any olfacto-
metric investigations as a basis for assessing
the odor situation. Nevertheless, both for the
waste treatment process itself and for subse-
quent landfilling of the residual waste, there can
be no doubt that the odor emissions are much
lower than if the untreated waste had simply
been dumped.
Most emissions in connection with MBWT occur
when the waste arrives, during its pretreatment,
and while the composting heaps are being put
up. In all pilot projects, the decomposition pro-
cess was seen to cause no odor-related pro-
blems. The coconut shells used as biofiltering
material in Phitsanulok served their purpose very
well. Such material itself occurs as a waste pro-
duct and is in abundant supply, free of charge.
Of course, to the extent that other kinds of
material are available (e.g. chopped garden trim-
mings), they can also be used.
Assuming that the decomposition process is
functioning properly, no annoying odor emis-
sions need be feared in connection with turning
or tearing down the heaps, or from emplacing
the pretreated waste at the landfill. The hoped-
for improvement in the odor situation at the
landfill thanks to waste pretreatment can gene-
rally be considered to have been fully achieved.
4.2.6.3 Hygiene
MBWT has the effect of extensively inactivating
or killing pathogenic microorganisms. Since it
was not possible to conduct any special hygiene
studies in connection with the pilot projects, the
hygienizing of the decomposing materials was
evaluated on the basis of the registered tempe-
rature profiles. In all field trials, the in-heap tem-
peratures remained above 55°C for several
weeks running (cf. Chapter 4.2.5.1). Accordingly,
an analysis of the time-history-of-temperature-
curves obtained in all pilot projects leads to the
conclusion that the waste material was hygieni-
zed by the decomposition process.
4.2.6.4 Process water
The quality and quantity of the emerging pro-
cess water depend on numerous different para-
meters, e.g. the composition and structure of
the waste, the height of the heaps, the tempera-
ture, the rates of evaporation and precipitation,
and the form of treatment employed. All three
pilot projects included examination of the pro-
cess water. Hence the results shown below can-
not be generalized, but apply only under the
given set of pilot-project boundary conditions.
Sector Project MBWT - Final Report
44
Figure 26: Coconut-shell biofilter at the Phitsanulok MBWT facility
For the first few days after the heaps are put up,
they may release what is referred to as water of
consolidation. In Al-Salamieh, the water regi-
mens of the various heaps were monitored and
analyzed in the course of the composting pro-
cess. Thanks to the cover, the only process
water to appear was this water of consolidation,
i.e. some 4 - 6 l of process water per Mg waste
emerged from the covered heaps during the first
few days of the process. Table 9, below, shows
the composition of the process water.
This process water is so polluted, that the base
of the biotreatment area will need a liner. Co-
vered and indoor heaps produce so little pro-
cess water during the decomposition process
that there is no problem in collecting and retur-
ning.
For uncovered, outdoor heaps, however, the
amount of process water produced during the
first few days of decomposition depends on the
duration and intensity of precipitation. Biotreat-
ment heaps can absorb small amounts of rain,
but the more rain falls, the less the heap can
store.
In São Sebastião, the process water emerging
from a commercial-scale test heap (230 m²) was
monitored with regard to quality and quantity.
The heap was put up on a specially sealed field.
45
Unit
Water content of input %
Process water fraction l/Mg Solids
pH -
COD
BOD5
Conductivity
Ammonium
mg/l
mS/cm
mg/l
mg/l
Heap of manuallysorted biowaste
58,5
4,2
7,4
12.230
15,2
145,0
36.780
Heap of mixed and commi-nuted household waste
57,1
3,8
6,8
6.580
14,9
144,0
24.750
Nitrate mg/l 0,7 0,8
Table 9: Quantity and quality of process water from biotreatment windrows in the Al-Salamieh scale-model trial
Sediment washout had very detrimental effects
on the operability of the analytical setup, so the
results of quantitative monitoring are only relia-
ble for the very brief period between May 15
and June 3, 2001. Some 98 l/m² of rain fell
during that period. Projected over the full area,
that results in 22,540 l of rainfall, while 7,245 l of
process water emerged from the test heap.
Figure 28 illustrates the course of the cumulative
curves over the period in question.
Process water began to emerge from the heap
about 2 days after the first rain. In the case
under review, some 30 % of the overall precipi-
tation eventually reappeared in the form of pro-
cess water.
The quality of the process water from the test
heaps in Rio de Janeiro and São Sebastião was
monitored over a prolonged period of time. Figu-
re 29 reflects the results of analysis.
Sector Project MBWT - Final Report
46
25.000
20.000
15.000
10.000
5.000
0
Sao Sebastiao projectTest heap
Vol
ume
(l)
Precipitation Process water
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22
Time (d)
Figure 28: Cumulative curves showing the precipitation onto and the processwater volume emerging from the test heap in São Sebastião
Figure 27: Test heap in São Sebastião
These results show that, during the first four
months of biological treatment, the process
water burden remains at levels that do not per-
mit its infiltration into the ground or its discharge
into an effluent stream. After that, the process
water burden gradually decreases, but never to
the point of negligibility any time before the end
of biological treatment. Consequently, the
decomposition process should always take pla-
ce on sealed surfaces.
Both in São Sebastião and in Phitsanulok, the
accumulated process water is used for watering
the heaps during dry spells. It is assumed in São
Sebastião that approximately one-half of the
incidental process water can be reused. The
remainder requires wastewater treatment.
47
65.000
60.000
55.000
50.000
45.000
40.000
35.000
30.000
25.000
20.000
15.000
10.000
5.000
0
Rio de Janeiro and Sao Sebastiao pilot projectsProcess water burden
mg/
l
0 50 100 150 200 250 300 350 400 450
Treatment time (d)
COD Rio
BOD5 Rio
COD Sao Sebastiao
BOD5 Sao Sebastiao
Figure 29: Quality of process water from test heaps in Rio de Janeiro and São Sebastião
Figure 30: Process water seeping out from the base of a heap in São Sebastião
4.2.6.5 Methane emissions
When untreated waste is landfilled, it generates
landfill gas. In its stable methane phase, landfill
gas consists of approximately 60 % methane
and 40 % carbon dioxide. The decomposition
processes employed in the pilot projects are
aerobic processes that release only minimal
amounts of methane, as long as the process
proceeds in its proper fashion. However, aerobic
decomposition can only be assured if the heap
receives a constant and adequate supply of
oxygen. In cases of insufficient aeration/ventila-
tion, anaerobic conditions will arise at various
points within the heap. This is evidenced by the
appearance of methane in the specimens when
the gas is analyzed. If the aerating effect is ade-
quate, the methane content of the analyzed spe-
cimens must consistently remain below 1 % by
volume. Methane contents between 1 % and
5 % indicate minor, insignificant disturbances
affecting the decomposition process. Methane
contents in excess of 5 % by volume, however,
indicate a seriously defective process, if they
last for any substantial length of time.
Thus with regard to the emission of climate-rele-
vant off-gases, MBWT represents a considerable
improvement over conventional landfilling practi-
ces. Overall, mechanical-biological waste treat-
ment reduces the amount of gas that would be
produced under normal-landfill conditions by
more than 90 % [5].
The methane emission levels measured during
the pilot projects were discussed in Chapter
4.2.5.3. Aerobic decomposition can only be
expected to make a positive contribution toward
climate protection if the heaps are always ade-
quately aerated, and regular gas monitoring is
necessary in order to detect anaerobic activity at
an early stage. Olfactory sampling and visual
inspections can only reveal deficits if the metha-
ne concentration is already quite high.
4.2.7 Disposal of pretreated waste
to the landfill
The subject waste-treatment concept does not
inertize the material to the point of making it
absolutely unalterable in the biological, chemical
and physical sense. Instead, the process only
stabilizes the waste input, and there will always
be some amount of residual waste that has to
be dumped. On the other hand, a landfill full of
MBWT-output material has little similarity with a
conventional landfill for untreated waste. Both
the technology involved and the environmental
impacts differ widely.
4.2.7.1 Fundamental considerations
When evaluating the performance of a mechani-
cal-biological waste treatment facility, one must
bear in mind that the properties of the treated
waste will depend on the process employed, the
length of treatment, the varieties of material
extracted, and the local boundary conditions. In
any case, the amount of biodegradable substan-
ce remaining behind in the residual waste will
have been substantially reduced. That, in turn,
means a decisive decrease in biological decom-
position processes within the landfill. The water
content will be lower, the mean particle size
smaller, and the pretreated material significantly
more homogeneous.
Sector Project MBWT - Final Report
48
For the evaluation of an MBWT facility, the way
it affects the present and future landfill situation
is of major importance. Within the scope of the
pilot projects it was not possible to evaluate
any longterm changes, because many such
effects take a number of years to become
apparent. However, some initial findings regar-
ding the ultimate disposal of pretreated waste
were secured both in São Sebastião and in
Phitsanulok.
Consequently, the situation in and around the
landfill can be expected to improve in the follo-
wing ways:
Less waste for ultimate disposal
The combination of biological degradation of
organic substance and possible extraction of
certain material varieties at the mechanical
conditioning stage markedly reduces the
residual quantity of waste to be disposed of.
The extent of the mass (or bulk) reduction
taking place in the course of biological treat-
ment results from the decrease in water con-
tent and total solids. The weight reduction
resulting from the loss of water is the diffe-
rence between the water content of the
input material and that of the end product.
The decrease in total solids, in turn,
depends on how much organic substance
(total organic solids) is degraded, and on its
percentage share in the total solids content.
Biodegradation proceeds at different intensi-
ty levels, depending on which natural sub-
stances predominate.
Firstly, the readily degradable components
decompose within a relatively short time,
while the substances that are more difficult
to break down become more concentrated
as the process progresses and the degrada-
tion rate slows down. Once biodegradation
of the easily degradable substances is com -
plete, the total organic content will remain
essentially unchanged up to the end of the
process. Within certain limits, the loss of
mass can be manipulated by the process
engineering invested. The extent of mass
reduction is, as a rule, largely dependent on
the length of the decomposition process and
on the amount of work and material that was
invested in the waste treatment.
Compaction
Thanks to pretreatment, residual waste
emplaced in thin layers can be compacted
to a much higher in situ density than can
waste in conventional landfills, and the land-
fill body sustaining much less settling after-
ward. Figure 31 compares various densities
of compaction, as ascertained for different
forms of waste pretreatment in Germany.
49
1,8
1,6
1,4
1,2
1,0
0,8
0,6
0,4
0,2
0
0,56 0,560,68 0,67 0,67
0,820,76 0,76
1,11
0,87
1,02
1,25
0,97
1,14
1,56
Co
mp
act.
den
sity
ρ dry
[t M
S/m
3] ρ
dry
ρ dry
*[t
TS
/m3]
Absolute density of compaction (dry)
Relative density of compaction (dry) based on
waste bulk prior to treatment
Density of compaction (moist)
BS I BS II BS III BS IV WH V*(Standard landfill) (Comminuted + (Comminuted, (Comminuted, (Comminuted,
thin layer) homogenized homogenized, homogenized, + thin layer) decomposed decomposed
+ thin layer) + thin layer)
Figure 31: Densities of compaction with and without pretreatment [6]
* other landfill siteMS = moist substanceTS = total solids
Less use of topsoil as daily cover
Many landfill areas are covered with topsoil
at the end of each day as a means of avoi-
ding waste exposure and in order to make
the surface traversable. However, the topsoil
ends up occupying a substantial share of
the landfill volume. Landfills reserved for
waste that has undergone mechanical-biolo-
gical pretreatment require no daily covers of
topsoil.
Longer useful life of landfill
The aforementioned factors help prolong a
landfill's useful life by a large measure.
Depending on the initial situation and the
MBWT process employed, the landfill's
useful life can be at least doubled.
Landfill leachate
In the medium term, the quality of leachate
can be expected to improve markedly, one
reason being that the phases of biological
degradation causing the most relevant orga-
nic pollution of the leachate take place prior
to deposition of the residual waste. Hence
the leachate burden, in terms of TOC and
COD, gradually decreases by as much as
90 %. On the other hand, the leachate also
picks up pollutants via extraction processes.
In the course of time, though, the compac-
ted waste becomes gradually less perme-
able, so less and less water can penetrate
into the landfill body, and accordingly less
leachate is produced.
Gas
MBWT reduces landfill gas production very
considerably. The actual extent of this
reduction depends on how much time the
material had to decompose. Decomposing
times of 20 weeks and longer can cut as
much as 95 % off of the residual gas
potential.
Landfill fires
Mechanical-biological waste treatment mar-
kedly reduces the danger of landfill fires.
Indeed, if the high-energy fraction is separa-
ted out, there will be no danger at all of
landfill fires.
MBWT improves the waste's placement and in-
dump behavior, while reducing its ultimate-
disposal volume. Nevertheless, no amount of
pretreatment can suffice to rule out the possibili-
ty of the landfill causing some environmental
pollution. For example, MBWT can do little to
break down any inorganic pollutants which may
be contained in the waste inputs, so such sub-
stances can continue to pollute the groundwater
after emplacement. Hence in professional cir-
cles, pretreatment is regarded as a supplemen-
tary measure, by means of which the environ-
mental health hazards emanating from landfills
can be mitigated. It has no effect on the stan-
dards to be met by landfills in any given country,
i.e. no such standards can be relaxed in advan-
ce because of MBWT.
On a case-by-case basis, though, the achieva-
ble results of waste treatment may be examined
with regard to the possibility or necessity of
gas collection or passive venting through a
surface filter,
dispensing with a surface cap for high den-
sities of compaction and low permeability,
and adapting the treatment of leachate to
allow for lower pollution levels and smaller
quantities.
Sector Project MBWT - Final Report
50
4.2.7.2 Mass reduction determined in
the pilot projects
The loss of mass (or bulk) due to
aerobic decomposition and the
remaining mass of organic material
in the product of biotreatment were
investigated as part of the Al-Sala-
mieh field trials. The moist mass
was weighed at the beginning and
end of the composting process,
and the water content of lots weig-
hing roughly 20 kg each was deter-
mined. The total organic content
was ascertained via the ignition loss.
In Phitsanulok, the loss of mass was determined
by weighing the waste input prior to mechanical
conditioning and after biological treatment. The
findings show that mechanical-biological waste
treatment reduced the moist mass by 53 %,
mainly in the form of lost water. At 19.2 %, the
organic decomposition rate is comparable to
data found in pertinent literature. The results
could probably be improved somewhat by opti-
mizing the MBWT processes beyond what was
achievable during the early phase of the Phit-
sanulok project. Figure 33 summarizes the
results.
51
1.600
1.400
1.200
1.000
800
600
400
200
0
577 465
211
938
Mas
s (M
g)
Phitsanulok project Mass reduction
Input to heaps A + B Output to heaps A + B
H2O TS
53 % reduction MS
19 % reduction TS
Duration of biotreatm. d
Input treatmentwater content of input
TOC of input
%%%
Output treatmentwater content of output
TOC of output
%%%
Loss of mass %
Hand-sorted bio-waste
100
10058,541,5
38,910,528,4
61,1
Mixed, commin-uted waste
110
10057,142,9
34,510,024,5
65,5
Figure 32: Emplacement of pretreated waste in São Sebastião
Table 10: Mass reduction through biotreatment in the Al-Salamieh, Syria, scale-model trials
Figure 33: Mass reduction in the pilot phase of MBWT in PhitsanulokMS = moist substanceTS = total solids
4.2.7.3 Emplacement trials in
the pilot projects
The main objective of landfilling is to make opti-
mal use of the - expensive - available emplace-
ment volume. Consequently, commercial-scale
compaction tests designed to ascertain the
maximum achievable density of compaction for
residual waste from a mechanical-biological
waste treatment facility by means of the pre-exi-
sting landfill compactor were run at the Phit-
sanulok landfill. The compactor in question
weighs 20 tons and is 3 m wide. A test field
measuring 15 x 15 m was staked out on undis-
turbed soil at the Phitsanulok landfill site.
Sector Project MBWT - Final Report
52
Turning area
15 m
15 m
Top of emplaced waste
Formation levelWaste
3,0 m > 7,95 m 3,0 m
Test-field Formation
Figure 34: Test-field dimensions for the commercial-scale compaction trial (Deutsche Gesell -schaft für Geotechnik e.V., Recommendation E 24, as modified)
Figure 35: Dry-season emplacement trial for pretreatedwaste at the Phitsanulok landfill in Thailand
The waste to be emplaced was weighed, spread
out across the test field by an excavator in lay-
ers approximately 30 cm thick, with each layer
being compacted in five passes. A tachymeter
was used to determine the volume of the empla-
ced waste.
The Phitsanulok landfill's 20-ton compactor
compressed the unscreened waste to an abso-
lute density of 1.10 Mg MS/m³ or 0.76 Mg
TS/m³. In Brazil, where a 30-ton compactor was
used, compaction densities of 1.1 - 1.4 Mg/m³
were measured in application of the volume-
replacement method.
The densities determined during the emplace-
ment trials were arrived at under dry weather
conditions. The emplacement of pretreated
waste is also unproblematic with regard to the
ground's load-carrying capacity and traver-
sability, as long as the weather stays dry.
However, past experience in Germany and São
Sebastião shows that the incorporation of pre-
treated waste becomes increasingly difficult with
increasing precipitation. As it absorbs water, the
waste becomes pasty and eventually impossible
to drive over or compact. If possible, then, no
waste should be emplaced during rainy periods.
Of course, that would be very difficult to put into
practice in regions with high precipitation rates.
There are various technical options for improving
the emplacement situation during rainy seasons,
but the scope of the pilot project did not allow
their testing.
53
1,2
1,0
0,8
0,6
0,4
0,2
00,17
0,760,53
1,1
(Mg
/m3 )
Phitsanulok project
Heaps A + B Density of compaction
Dry density
Moist density
Figure 36: Comparison of in-heap densities and achieved landfill compaction densities
4.2.7.4 Landfill leachate in São Sebastião
A landfill reserved for pretreated waste has been
in operation in São Sebastião since the fall of
2002. The leachate is collected and routinely
sampled to keep tabs on the typical parameters
shown in Figure 37.
These investigations confirm expectations to the
effect that pretreatment definitely improves the
quality of landfill leachate. However, long-term
studies would be necessary to arrive at any reli-
able information on leachate incidence and
emburdenment.
4.2.8 Costs
4.2.8.1 Costing principles
To assess the cost of waste treatment, one must
customarily weigh out the capital investment,
the cost of operation, and the revenues. Having
obtained that information, one can calculate the
annual costs and the specific cost per ton of
handled waste. The annual costs, i.e. those that
recur each year, comprise the following items:
annual capital (servicing) costs (e.g. initial
cost of equipment and construction, real
estate, etc.)
throughput, independent (nonvariable) ope-
rating costs (e.g. insurance premiums, lease
payments, etc.)
Sector Project MBWT - Final Report
54
2.200
2.000
1.800
1.600
1.400
1.200
1.000
800
600
400
200
0
MBWT landfill in Sao SebastiaoLeachate burden
mg/
l
07/23/02 08/22/02 09/21/02 10/21/02 11/20/02 12/20/02 01/19/03 02/18/03
Time
1st emplacement in July 2002
COD BOD5 NH4-N
2nd emplacement in December 2002
Figure 37: Leachate burden at the MBWT landfill inSão Sebastião
throughput-dependent operating costs
(e.g. electricity, fuel, residual-waste dis-
posal, etc.)
returns (e.g. proceeds from the sale of
recyclables)
Since there are so many variants to choose
from, the cost of mechanical-biological waste
treatment can vary widely. Other specific-cost
factors include the plant throughput rate (mean-
ing that the specific costs decline with increa-
sing throughput rate) and the capacity utilization
rate (meaning that the specific costs rise with
decreasing capacity utilization rate). However,
these costs do not transfer readily from one
country to the next, because:
the expenditures for personnel, construction
and energy, in addition to the customs and
tax laws, vary widely from country to country
and from region to region,
country-specific standards for emission con-
trol, wastewater purification, monitoring,
etc., exert a major influence on costs,
fluctuating exchange rates can alter the cost
of capital goods and operating supplies.
Hence the cost of personnel accounts for a lar-
ge percentage of the overall cost at extensive
facilities in countries with high wages. Conver-
sely, in countries with low labor costs, the per-
sonnel costs account for a much lower percen-
tage of the overall cost. At intensive facilities,
the cost of labor accounts for a lower percenta-
ge of the overall cost, while customs regulations
and conditions of supply and warranty are much
more important.
If the results of cost determination are to be reli-
able, the boundary conditions of each concrete
case must also be taken into consideration. One
should also keep in mind that considering the
cost of waste treatment only could lead to erro-
neous conclusions. After all, mechanical-biologi-
cal waste treatment influences all the other
aspects of waste management, too, so the enti-
re disposal system must be accounted for in any
proper cost assessment. Only then can the
additional costs of mechanical-biological waste
treatment be properly compared with and
weighed against corresponding cost reductions,
particularly with regard to final disposal
(cf. Chapter 4.2.8.3).
4.2.8.2 Examples of costs incurred in
the pilot projects
The cost calculations for the pilot projects in
Brazil and Thailand, as well as for the scale-
model trial in Syria, are presented and discussed
below. The cost of waste treatment in Brazil can
be determined fairly accurately, because the
project was of long duration, and normal opera-
tion has already commenced. The project in
Thailand is still in its pilot phase, so no complete
sets of data are available, especially not for the
variable costs of operation. However, the same
process with the same procedures and the
same equipment can be employed for normal
operations here, too. Moreover, the availability of
extensive pertinent analyses and calculating
models makes it possible to at least determine
the general orientation.
By reason of the differences in process techno-
logy, the project in Syria is interesting for com-
parison purposes. However, the cost estimates
for Syria are not unconditionally comparable
with those of the other two projects because
they are based on the experience drawn from
and the assumptions made in the (220-ton) field
trial. These same assumptions have not yet
been verified in any large-scale field trial.
The basic prerequisites for calculating project
costs differ from case to case, sometimes sub-
stantially. For example, no interest rates were
included in the calculations for Phitsanulok,
because that would have run counter to the nor-
mal investment financing practices of Thai com -
munities.
55
With a view to rendering the cost calculations
mutually comparable as regards process-speci-
fic and conceptual differences, the pure cost of
treatment (MBWT) was figured on the basis of
available data, while the cost of waste collec-
tion, delivery and subsequent disposal were left
out of the sample calculations, even though they
would have been applicable. Hence the costs
considered covered the preparation of MBWT
areas, the technical equipment, maintenance
and repair costs, and the collection and treat-
ment of any incidental leachate.
The computations are also based on numerous
assumptions designed to allow the estimation of
unknown costs and to make project-specific
calculatory approaches mutually comparable.
Hence the stated figures are suitable for use in
documenting the various (project- and country-
specific) factors of influence and for illuminating
the scale of the anticipated costs.
Costs resulting from the company's cooperative
efforts in the respective countries (e.g. license
fees, training, etc.) have been omitted, as have
the outlays for land acquisition and planning.
The specifics of the individual projects with
regard to cost determination are listed below:
Brazil
Ample spare waste-treatment capacity is
needed here, because the area hosts nume-
rous tourists during the main traveling sea-
son. For four months each year nearly twice
as much landfill labor and operating supplies
are needed as during the rest of the year.
The landfill serves a very large area, and
some of the waste has to be hauled in from
as far away as 100 km. Consequently, the
cost of waste transport is accordingly high
and must be allowed for in the waste
management concept.
Decomposing heaps that cannot be put up
on the old landfill require some form of rein-
forced profiling. These areas are presently
being prepared by means of a bulldozer /
grader and an HDPE tarpaulin (geomembra-
ne lining). A lump sum per square meter was
taken into consideration as the cost of treat-
ment-area preparation.
Due to the large distance between the land
fill and the wastewater treatment plant, the
cost of leachate disposal is relatively high.
On the other hand, no other special equip-
ment is needed directly at the landfill.
The planned use of green waste and pru-
nings as structural material or as a biofilter
was not allowed for in the calculations.
The heaps are watered by means of gasoli-
ne-engine-driven pumps feeding into a sim-
ple system of hoses and sprinklers. These
costs are also figured into the variable ope-
rating costs as a lump-sum item.
Sector Project MBWT - Final Report
56
Thailand
By reason of Thailand's public-sector invest-
ment policy, no interest rates have to be
accounted for, because all investments are
directly financed. However, in the interest of
comparability, a 6 % capital interest rate
was figured into the calculations.
The biotreatment area was prepared accor-
ding to a relatively elaborate technique cor-
responding to the base of the landfill body.
The cost of consumables, maintenance and
repairs can only be estimated, because the
plant has not yet entered its regular opera-
tion phase at nominal throughput. The esti-
mates were made on the basis of facts alre -
ady established.
The treatment of process water has been
integrated into the treatment of leachate, so
the cost of leachate treatment is accounted
for here as a proportion of the overall invest-
ment costs. No operating cost data are avai-
lable.
Watering is effected via a pump and sprink-
ler system. Again, no operating cost data are
available.
Under the present circumstances, the mate-
rial used for the biofilter is obtained free of
cost, i.e. producers deliver it to the landfill
free of charge.
Syria
The postulated costs are in line with the
data gathered in the course of the field trial.
They are not based on empirical data or on
figures deriving from actual operation of a
plant. Consequently, these costs must be
regarded as the minimal process costs wit-
hin the local context. Hence this project
does not lend itself well to comparison with
others. Especially with regard to operating
costs, no reliable information is available.
Since the design of the plant is not yet com-
plete, the technical equipment has not yet
been outlined or sized. For purposes of
comparison, an equipment fleet consisting
of a homogenizing drum, a screener, a wheel
loader and a truck was postulated.
Prices cited by local manufacturers were
assumed here as the cost of procurement
for a homogenizing drum and screener nee-
ded for conditioning the waste input. Consi-
dering the empirical data collected in other
projects, the suitability of the equipment,
and hence of its durability and depreciation
expenses, are somewhat questionable.
Thanks to the fact that the composting time
is shorter than for passively aerated heaps,
the treatment area is correspondingly smal-
ler.
The heaps require no watering.
The postulated investment costs plus main-
tenance and repair expenditures also cover
the cost of the biofilter / seal / cover.
All costs are stated as specific costs in relation
to the plant's projected annual throughput.
57
Sector Project MBWT - Final Report
58
Table 11: Comparison of specific costs in the pilot projects
Pos. Project Sao Sebastiao, Brazil
Data basis Normal operation
CharacterizationFaber-Ambra, normal ope-ration for all waste inputs, 9 months of decomposition
Phitsanulok, Thailand Al- Salamieh, Syria
Pilot-scale field trial Scale-model trial
Faber-Ambra, postulatedfor target throughput,9 months of decomposi-tion
Gore laminate process, sta-tic, actively aerated heaps,3 to 4 months of decompo-sition
Notes No plans for screeningdrum or comminution ofgreen waste; no landfilling
Operating costs indetermi-nate for watering and lea-chate disposal
Costs roughly calculatedand only conditionally com-parable; suitability of localequipment requires furtherstudy
Annual throughput 30.000 Mg 32.850* Mg 20.000* Mg
Specific costs Specific costs Specific costs
Designation [€/Mg Input] [€/Mg Input] [€/Mg Input]
1. Investment costs 3,8 € 5,0 € 6,8 €
1.1 Buildings + infrastructure 0,4 € 2,4 € 0,1 €
1.2. Technical equipment 3,4 € 2,6 € 6,7 €
1.2.1. Comminution homogenization 1,9 € 1,4 € 0,2 €
1.2.2. Excav., wheel loader transport 1,5 € 0,9 € 2,1 €
1.2.3. Ventilation / cover / watering -- € 0,3 € 4,2 €
1.2.4. Leachate collection and treatment -- € 0,1 € 0,2 €
2. Wages and salaries 1,7 € 0,8 € 1,1 €
3. Maintenance and repair 2,2 € 1,6 € 2,8 €
4. Var. operating costs 7,1 € 3,3 € 1,1 €
4.1 Fuel/lubricants 2,4 € 0,7 € 1,0 €
4.2 Ventilation 1,0 € 2,6 € < 0,1 €
4.3 Watering 0,3 € -- € -- €
4.4 Biofilter/cover/seal 2,5 € -- € -- €
4.5 Leachate disposal 0,9 € -- € < 0,1 €
Total 15 € 11 € 12 €
Allowance for cost risks -- € + 2,1 € + 3,5 €
* Planned/projected plant throughput** The costs of leachate collection and of the leachate pond are included in the construction costs (Item 1.1)
**
The following assumptions were made in esti-
mating the existing uncertainties (margin of safe-
ty):
Phitsanulok
Since the MBWT facility is still in its pilot-scale
field trial phase (30 Mg/d), and since some of
the costs can only be estimated, a 20 % safety
allowance was added to the overall costs to
account for unforeseen items.
Al-Salamieh
Cost basis: comminution / homogenization
at German rates (EUR 175,000 instead of
EUR 25,000 for the homogenizing drum and
rotary screener)
Additional personnel required (+25%)
Higher fuel / energy consumption (+25%)
The following diagram illustrates the cost com -
position.
59
18
16
14
12
10
8
6
4
2
0
3€
7€
2€
2€
4€
2€
2€
1€
5€
4€
1€
3€
1€
7€
Sp
ecifi
c co
st o
f M
BW
T [
EU
R/M
g]
Pilot-project cost calculations vs. cost estimate for Al-Salamieh, Syria
São Sebastião , Brazil Phitsanulok, Thailand Al-Salamieh, Syria
Investment costs Maintenance & repair Wages & salaries
Variable operation costs Safety allowance for cost estimate
Figure 38: Comparison of pilot-project cost calculations (specific costs in EUR/Mg)
When interpreting the above figures it is impor-
tant to keep in mind that the Al-Salamieh project
is not directly comparable with the other pro-
jects, because the plant is still at the planning
phase and no practical experience has been
gained to date.
The various calculations yield overall costs of
mutually similar proportions. The specific invest-
ment costs of the process employed in Syria are
approximately 30 % higher than those of the
FABER-AMBRA® process, because the techni-
cal equipment fleet is more expensive. Conspi-
cuously, the operating costs are roughly twice
as high in Brazil as they are in Thailand and
Syria. This is partially attributable to differences
in the local situation (e.g. higher waste incidence
during the tourist season, high personnel costs
and expensive biofilter material), but probably
also to the greater reliability of the Brazilian
data.
The variable operating costs of the FABER-
AMBRA® process were essentially defined by
the cost of the aerating course and the biofilter.
The costs of fuel and lubricants for the projects
in Thailand and Syria were extrapolated from the
current consumption rates and, respectively,
estimated on the basis of the mechanical equip -
ment used. Likewise, presently available infor-
mation does not allow quantification of the
watering and leachate-treatment costs in Thai-
land. The energy consumption rates assumed
for ventilation in the Syrian project are very low.
4.2.8.3 Effects of MBWT on the cost of
waste disposal
The MBWT costs described above in Chapter
4.2.8.2 at least partially offset the net cost of
waste disposal. The cost-related effects of
MBWT were explained in Chapter 4.2.7. The
costs of the various residual-waste treatment
alternatives were estimated within the scope of
a comprehensive cost investigation for the pro-
ject in Phitsanulok, Thailand. The effects of
MBWT on the cost of waste disposal were des-
cribed for the following set of boundary condi-
tions:
Pure landfilling: continuation of landfill ope-
rations (approx. 90 Mg/d) in the present
form; optimization of placement practice.
MBWT / landfill: combination of MBWT (with
all incoming waste, i.e. approx. 90 Mg/d,
being given the full treatment) and subse-
quent landfilling (thin-layer emplacement),
which prolongs the useful life of the landfill,
causes less leachate to be produced, and
means that the landfill requires less
aftercare.
Sector Project MBWT - Final Report
60
As the two columns in Figure 39 plainly show,
pretreatment reduces the specific landfilling
costs by some 50 %. This extensively offsets
the cost of MBWT. Most of the gain is attributa-
ble to prolongation of the landfill's useful life.
4.2.9 Informal sector
In many countries, all or most waste is proces-
sed by the informal sector. The levels of inter-
vention of the informal sector are illustrated in
Figure 40.
61
16
14
12
10
8
6
4
2
0
Sp
ezifi
c c
ost
s [€
/Mg
]
Comparison of specific landfilling costs with and without MBWT
Landfill MBWT/landfill
Approx. 50% lower
landfilling costs
Cost of landfill aftercare
Cost of landfill operation
landfill investment costs
Recycling material
Organic materialResid wasteTotal waste
Intervention by informal sector
Wasteincidence
Putting outfor collection
collection(mixed)
Reloading Hauling Industry
Separationby producer
collection(seperate)
Sorting
Composting
Incineration
MBWT
Agriculture
Disposal
Figure 39: Comparison of specific landfilling costs in Phitsanulok with and without MBWT (specific costs in EUR/Mg)
Figure 40: Informal-sector intervention in the flow of household waste
(c) Wehenpohl / A.L.F. dos Santos; 01/2000
The informal sector in waste management does
not consist solely of people with low incomes,
but also includes, in various numbers, all clas-
ses: for instance intermediate dealers (brokers),
owners / proprietors of (further-processing) recy-
cling businesses, etc. The introduction of MBWT
in combination with controlled landfilling
amounts to a partial reorganization of the waste-
management sector, and any changes effected
can alter the boundary conditions for the infor-
mal sector.
With a view to preventing negative impacts, and
perhaps even to offering the sector some work-
able alternatives, submeasures designed to pro-
mote integration of the informal sector were built
into the sector project. In Brazil, for example,
where the informal sector is traditionally very
prominent, the sector project provided support
to another project being implemented in parallel
with the MBWT pilot project. This project was
called "Formalization of the Informal Waste-
management Sector in São Sebastião and Ilha-
bela". The project, termed Cooperativa de Tria-
dores (cooperative for the recovery of recycla-
bles), sponsored by the São Sebastião munici-
pal administration, is geared to reducing the
inflow of waste to the local landfill and to the
pursuit of additional objectives in the areas of
social and environmental policy. For example, a
program of separate collection and subsequent
sorting of waste and recyclables is intended to
create income opportunities for the poor and
needy. The program, it is hoped, will offer that
group some future-oriented, economically feasi-
ble perspectives. Simultaneously, by esta-
blishing the cooperative for the utilization and
sale of recyclables, the authorities hoped to
involve people more in waste management. The
relevant skills of the individuals concerned were
systematically improved via training and motiva-
tion measures. One of the criteria for participa-
ting in the program was that adults take part in
the training.
Results:
The group was officially registered as a co-
operative (in North-Center and Ilhabela).
The monthly income of the members increa-
sed more than twofold.
The amount of recycled waste was increa-
sed substantially as the members became
familiar with methods that increased the effi-
ciency of their work and improved the
results of dedicated sorting.
Some of the recyclables were sold directly
to the processing industry without the need
for brokers, so the revenues were much hig-
her.
Sector Project MBWT - Final Report
62
Figure 41: Members of the Ilhabela Cooperativeat work sorting recyclables
The success of these measures greatly increa-
sed the members' motivation and improved their
standing with the municipal authorities.
The following recommendations and conclu-
sions can be drawn from the results of support
given in São Sebastião and Ilhabela:
Some of the people populating the various
parts of the informal waste-management sec-
tor cannot be successfully integrated into more
formal structures, because, among other fac-
tors, some are alcoholics and/or drug addicts,
and some are unable to subordinate themsel-
ves to regular work regimens.
In São Sebastião, some people who had
never before worked in the waste-management
sector were successfully integrated into waste-
sorting processes, despite the fact that this is
generally viewed as a repulsive field of work.
Experience shows that the chance to earn
one to three times the minimum wage working
in this sector can attract people from low-inco-
me brackets who have not previously worked
in the sector.
Municipal waste management is a communi-
ty task. As such, the community's consent is
required for integrating these people without
adopting a paternalistic stance.
The development of formal structures requi-
res the support and backstopping of external
specialists (social workers, accountants,
lawyers, waste-management technicians, etc.).
Two to three years of support will probably
be necessary.
Granting small-scale loans to such groups
can have a supportive effect but needs to be
considered on a case-by-case basis and
should not be allowed to become too much
of a burden on the group. Experience in
other areas shows that small, short-term
loans are often more appropriate than large,
long-term loans, because it is easier to learn
how to deal with them. Credit organizations
should be advised of this.
63
5.1 Conclusions Drawn from the Pilot
Projects
As the pilot-project examples show, mecha-
nical-biological waste treatment can be
successfully implemented in developing and
threshold countries. In the pilot projects featured
here, the biological decomposition processes
employed yielded good results and hence achie-
ved the primary goal of improving the in-dump
behavior of the residual waste. In São Se-
bastião, MBWT has already radically improved
the landfill situation and become a fixed compo-
nent of the city's waste-disposal concept.
The MBWT version tested in Syria, i.e. with
cover and forced ventilation, is a more elaborate
technology, but it amounts to a very promising
approach for areas with little water as well as for
areas with high rates of precipitation. The next
step will be to engage in commercial-scale
application of the results of the field trial. If the
production of high-quality, marketable compost
in Al-Salamieh is to be assured in the long term,
the separate collection of organic waste will
have to be expanded step by step.
The specific costs of pretreatment determined in
the pilot projects range between 11 and 15
EUR/Mg input. However, if the economizing
effect that MBWT has on landfilling operations is
subtracted from the costs of MBWT, the remai-
ning specific costs drop to just a few Euros by
comparison with those of landfilling waste
without pretreatment. Indeed, in Phitsanulok, the
cost of waste disposal with and without MBWT
is practically identical. Moreover, the combina-
tion of mass reduction and improved compressi-
bility achieved via MBWT can lengthen a landfil-
l's useful life several times over. On the other
hand, even Germany's time-tested "simple pro-
cesses" have to be accommodated to the local
boundary conditions prevailing in other countries
in order to achieve the desired results. In that
sense, the "simple processes" used in the pilot
projects make it possible to introduce MBWT on
an initially small scale, and then to gradually
expand the throughput if the results are suc-
cessful.
One of the main criteria for the successful intro-
duction of MBWT is that the future operator
must be willing and able to indefinitely ensure
adherence to the operational requirements. Both
the operation of the MBWT facility and the
emplacement of residual, pretreated waste at
the landfill call for a large measure of expertise.
Despite the long duration of the pilot projects
and the training given to municipal workers,
sustainable operation of the MBWT facilities by
the communities themselves with no external
assistance could not have been assumed reali-
stically for either São Sebastião or Phitsanulok.
Communities that have nothing other than nor-
mal garbage dumps could not be expected to
meet the prerequisites for competent operation
of MBWT facilities without first having radically
altered their boundary conditions. In addition to
having qualified staff, successful implementation
of this new technology often requires internal
structural and organizational reform measures.
For any existing municipal administration, insti-
tuting such reforms must amount to a weariso-
me, time-consuming process. With a view to
accelerating the process, much can be said in
favor of establishing private-sector structures for
operation of an MBWT facility. However, even if
the facility is privatized, integration of the requi-
site expertise must be assured. As a rule, local
contractors lack such expertise, so partnerships
with competent external enterprises are recom -
mended. Such an approach has already been
implemented in São Sebastião, and similar
arrangements appear to be emerging in the
other pilot projects as well.
Sector Project MBWT - Final Report
64
5 Future Prospects of MBWT in Developing and
Threshold Countries
The close cooperation between GTZ, the partner
communities and private enterprises practiced in
the sector project has proved fruitful and contri-
buted decisively to the success of the pilot pro-
jects. Hence cooperation between communities
and private enterprises - public-private partners-
hips (PPP) - would appear to be sensible and
advisable for future implementation of MBWT in
developing and threshold countries. German
companies can assume an important role here.
Any disposal tasks to be contracted out to pri-
vate enterprises must be unequivocally descri-
bed in terms of the services to be rendered, and
all such services must be readily and unequivo-
cally verifiable for the communities. The results
of the sector project show that the attendant
quality control programs are not yet amenable to
local implementation. Consequently, programs
and methods of performance monitoring that are
commensurate with the communities' own
capabilities have to be developed.
All in all, the pilot projects generated lots of
public attention. Numerous native and foreign
visitors have toured the pilot projects in São
Sebastião and Phitsanulok, and the first pilot
projects dealt with in this report have since
given rise to numerous MBWT projects. In Bra-
zil, for example, other communities are also gea-
ring up to use MBWT as a component of their
municipal waste disposal systems. Hence the
São Sebastião pilot project has fully fulfilled its
function as a model project.
65
5.2 Comparison of Alternative Waste
Disposal Concepts
The pilot projects proved that MBWT can, under
certain sets of boundary conditions, serve as an
effective component of municipal solid waste
disposal in developing and threshold countries.
However, that does not answer the question as
to whether MBWT also constitutes the most
cost-effective solution. An objectively sound
decision can only be arrived at on a case-by-
case basis and in due consideration of all rele-
vant aspects. The various member countries of
the European Union give preference to different
avenues of disposal. According to the results of
the survey illustrated in Figure 42 below, some
70 % of all waste produced in the EU is dispo-
sed of in landfills, and approximately 20 % is
incinerated.
Sector Project MBWT - Final Report
66
100
90
80
70
60
50
40
30
20
10
0
Ave
nues
of
dis
po
ral [
wt.
%]
Avenues of waste disposal in the EU member countries
AU BE DK FI FR GE GR IR IT LU NL PO SP SW UK EU
Landfilling Incineration with energy recovery Incineration without energy recovery
Composting MBWT / landfill Fermentation
Figure 42: Avenues of waste disposal in EU member countries in 1999 [7]
Except in a few urban agglomerations, the inci-
neration of municipal solid waste in developing
and threshold countries is not a viable avenue of
disposal, if only for economic reasons. However,
the objective of reducing the emission potentials
of MSW could also be achieved by means of
separate collection and recycling of the organic
components. Another conceivable solution is to
combine composting with MBWT.
In any case, the benefits of the various alternati-
ves can only be secured if certain assumptions
are fulfilled. For example, the anticipated results
of MBWT decomposition processes can only be
achieved if the facility is actually being operated
with due competence. Likewise, the hoped-for
income from composting can only be realized if
the compost is of good quality and can be suc-
cessfully marketed.
The comparison of alternatives as a basis for
deciding on a waste disposal concept will
always include some unavoidable uncertainties.
The degree of uncertainty will depend on how
much experience has been gained through
application of the various alternatives. In order
to minimize the risks resulting from uncertain
assumptions, new processes should always first
be field-tested and then implemented in stages.
Extensive MBWT processes, for example, can
be tested by way of scale-model trials followed
by large-scale pilot schemes to establish the
process suitability while adapting it to fit the
local boundary conditions. The treatment pro-
cesses dealt with in this report allow such a
step-by-step form of introductory implementa-
tion.
Also, MBWT enables the separation of high-
energy fractions at the mechanical conditioning
stage. That, in turn, makes it possible to integra-
te additional paths of recovery and disposal into
the waste management system, extending
beyond mere improvements in the waste dispo-
sal situation.
5.3 Need for Further Study
This sector project provided a crucial point of
departure for assessing the perspectives of
MBWT in developing and threshold countries,
but the duration of the project did not suffice to
find conclusive answers to all questions, and
there was little empirical background to draw on
regarding the construction and operation of
lined and sealed landfills in tropical and subtro-
pical areas. Indeed, the since acquired know-
how shows that waste-disposal standards deve-
loped in Central Europe cannot be applied to
such areas without further ado. Hence there is a
continuing need for further investigation into
various aspects of MBWT, including and in parti-
cular the following:
Landfilling concept as a function of climate and
waste composition
Observations made at landfills in tropical and
subtropical areas show that organic decomposi-
tion proceeds much more rapidly there than it
does in more temperate climates. A systematic
analysis of relevant empirical data could have a
fundamental impact on the operation of such
landfills. For example, the prevailing routine
practice of immediately compacting the empla-
ced waste and covering it with a layer of topsoil
at the end of each day requires systematic
management of the incidental leachate and
landfill gas. That, however, is still unrealizable in
many countries. Consequently, different ways of
modifying landfill concepts to achieve extensive
aerobic decomposition of the organic fraction
directly at the landfill need to be investigated
(including "shredded refuse landfills" as the
most elementary form of MBWT).
67
Development of appropriate leachate-treatment
strategies
It makes no sense to line a landfill unless the
leachate can be reliably disposed of. However,
German leachate-treatment standards cannot be
realized in most developing and threshold coun-
tries. What are therefore needed are leachate-
treatment concepts that are feasible in both the
technical and the financial sense. On the other
hand, the importance of MBWT increases in tan-
dem with the risks and costs of leachate treat-
ment.
Climate relevance of waste pretreatment
The anaerobic decomposition of organic waste
in landfills generates large amounts of climate-
destabilizing methane. Even quite elaborate gas-
management systems are only able to trap part
of the generated methane, and in many coun-
tries any efficient form of gas collection and
recycling would simply be too expensive. Thus
waste pretreatment constitutes a comparatively
simple and efficient way of reducing methane
emissions. The effects of various waste disposal
concepts that could be implemented in develo-
ping countries need to be investigated in terms
of their climatic impacts. Then the findings
should be used to develop standards for ensu-
ring that decisions on waste-disposal concepts
are made in due consideration of climatic fac-
tors.
Material-flow steering and waste recycling
The mechanical conditioning stage of MBWT
allows the separation of waste fractions for pur-
poses of recycling and energy recovery. In many
developing and threshold countries the informal
sector has traditionally been largely responsible
for the recovery of resources. Consequently,
concepts geared to increasing the recycling
quotas should allow for the needs and capabili-
ties of the informal sector. Projects in Ilhabela,
Brazil, and in Atlacomulco, Mexico, have yielded
experience in informal-sector involvement, and
the lessons learned there need to be broadened
and disseminated.
Landfilling of pretreated waste
With regard to in-dump behavior, MBWT waste
differs greatly from untreated waste. Its main
advantages include better compressibility and
less emission potential. However, the studies
conducted within the scope of the pilot projects
have shown that the disposal of pretreated
waste in landfills in areas with high rates of pre-
cipitation is inherently problematic. Ways and
means of optimizing the emplacement of pretre-
ated waste in areas with high rates of precipita-
tion need to be developed.
Long-term in-dump behavior
One of the main advantages of MBWT is that it
promises to radically improve the landfill situa-
tion. Precisely for that reason, however, there is
need for further investigation of the long-term
behavior and leachate emissions of pretreated
waste.
Monitoring
Germany has extensive codes and standards
and the appropriate technical equipment for
securing and monitoring waste treatment and
disposal targets. Many developing and threshold
countries, however, still lack all or some of the
corresponding codes, standards and equipment.
It is therefore necessary to develop and imple-
ment appropriate standards and monitoring
methods.
Sector Project MBWT - Final Report
68
This report presents the main activities and
results of the sector project "Promotion of
Mechanical-biological Waste Treatment", which
was carried out by Deutsche Gesellschaft für
Technische Zusammenarbeit (GTZ) GmbH from
1998 to 2003 on behalf of the Federal German
Ministry for Economic Cooperation and Deve-
lopment (BMZ). The purpose of the project was
to investigate potential applications for mechani-
cal-biological waste treatment in developing
countries by way of know-how interchange, pilot
projects, etc. and to describe the prospects and
risks of application.
In addition to drawing up reference material and
decision-making aids for MBWT applications,
the sector project also focused on practical field
testing of mechanical-biological waste treatment
in various countries under various sets of boun-
dary conditions (e.g. climate and waste compo-
sition). Several specialized German enterprises
served as partners in cooperation for preparing
and implementing the "pilot projects". This co-
operation with the private sector made it possi-
ble for the pilot projects to employ processing
techniques and throughput rates that closely
resembled those encountered in normal opera-
tion, hence yielding reliable results. The pilot
projects also included as important components
training programs designed to gradually put the
partners from developing and threshold coun-
tries in a position to handle the field-tested tech-
nologies on their own.
The results are essentially outlined in this report
on the basis of the commercial-scale pilot pro-
jects in São Sebastião, Brazil, and Phitsanulok,
Thailand, and the scale-model trial in Al-Sala-
mieh, Syria. Both in São Sebastião and in Phit-
sanulok, a non-mobile biotreatment-windrow
approach (FABER-AMBRA® process) was adop-
ted, while force-ventilated heaps with an inert,
semi-permeable laminated-tarpaulin cover (W.L.
Gore) were used in Al-Salamieh.
The experience gained in the pilot projects
shows that mechanical-biological waste treat-
ment can be successfully implemented in deve-
loping and threshold countries. The biological
decomposition processes employed in the sub-
ject pilot projects achieved satisfactory results.
The São Sebastião MBWT facility has since
commenced normal operation and yielded a
radically improved landfill situation.
The specific pretreatment costs determined in
the course of the pilot projects range between
11 and 15 Euro/Mg, but MBWT does not only
generate costs, it also generates savings in
waste disposal. The economizing effect at the
landfill end stems mainly from a reduction in
mass and the enhanced compressibility of the
pretreated waste. MBWT also reduces leachate
incidence and pollution, as well as the formation
of landfill gas. MBWT can reduce the cost of
landfill aftercare and increase several times over
the useful life of landfills.
69
6 Summary
On the other hand, the project also revealed that
in order to achieve the targeted results, even
"simple techniques" that have already been
well-proven in Germany require appropriate
adjustment to the respective local situation in
other countries (especially with regard to climate
and waste composition). One of the main criteria
for the successful introduction of MBWT is that
the future operator be willing and able to inde-
finitely ensure adherence to the operational
requirements. Both the operation of the MBWT
facility and the employment of residual, pretrea-
ted waste at the landfill call for a large measure
of expertise. Despite the long duration of the
pilot projects and the training given to municipal
workers, sustainable operation of the MBWT
facility by the communities themselves, i.e. with
no external assistance, could not have been as-
sumed realistically. In São Sebastião, the crea-
tion of private-sector structures, including the
participation of a German enterprise, made it
possible to ensure the long-term operation of
the MBWT facility.
Sector Project MBWT - Final Report
70
The results of this sector project provide a good
basis for evaluating the perspectives of MBWT
in developing and threshold countries. Under
favorable boundary conditions MBWT can also
constitute an effective element for the disposal
of municipal solid waste. Whether or not MBWT
would actually be the most favorable solution in
any given case can only be decided in due con-
sideration of all relevant aspects. Since the
duration of the project did not suffice to find
conclusive answers to all questions, this report
calls attention to some remaining uncertainties
and to the need for further studies and
investigations.
71
APPENDICES
Sector Project MBWT - Final Report
72
Appendix 1 Characterization of the Pilot Projects
Project characterization - São Sebastião, BrazilProject designationPilot Project, São Sebastião, Brazil
Country, communityBrazil, São Sebastião
Beginning, endMay 2000 - end of 2002
CharacterPublic-private partnership
MiscellaneousThe local government has adopted the process on the basis of alicense model. MBWT and landfill privatized in March 2002
Partners in cooperationGTZ sector project "Promotion of Mechanical-biological Waste Treatment" Official contact Elke Hüttner, Division OE44; Phone: ++49 6196 79 0e-mail: [email protected];Internet: www.gtz.de/mba/
Wilhelm Faber GmbH Wolfgang Tönges; Phone: ++49 6731 492 - 117e-mail: [email protected]; Internet: www.faber-ambra.de
Prefeitura Municipal de São SebastiãoSecretaria de Meio Ambiente e Urbanismo; Secretário Sr. José Teixeira FilhoRua Amazonas 13Centro - São Sebastião - SP - 11600/000Tel. +55-12-38926000; Fax. +55-12-38922819 Internet: www.saosebastiao.sp.gov.br
DescriptionShort description of the project Pilot project for appraising the suitability of, and appropriately adapting, the FABER-AMBRA® process of Wilhelm Faber GmbH(non-mobile, passive ventilation, with mechanical pretreatment) for application in Brazil; transfer of process know-how via trainingand local backstoppingLocal integrationIntegration into the landfill environment, treatment of all waste inputs since March 2002, disposal to mono-landfill since June 2002
Technical descriptionBasic waste-management dataPopulation served: approx. 65,000 year round, and up to300,000 during the summer tourist seasonRainy season: Nov.-Mar., approx. 2,400 mm annual precipitation Annual waste input: 30,000 Mg (in 2001)Waste composition: 50 - 60 wt.% organicsWater content: > 60 wt.%Plant capacity: up to 250 Mg/d, 30,000 Mg/a
Employed technologyDelivery by collecting vehicle or container truckRegistration of weight and origin via truck weigherConditioning/preparation Manual presorting by employeesHomogenizing drum, i.e. modified rotary drum vehicle from Ger-many, capacity: 7 MgTotal of 3 vehiclesHomogenization and comminution of waste inputEach batch takes 70 minutes, incl. 45 min for homogenizationDecompositionPreparation of heap base with pallets and drain pipesBuilding of heaps with excavator (30-39 m wide, 2.5 m high)Covering with biofilter, installation of watering system and sam-pling gaugesDecomposing time: 9 months; temperature-controlled processTeardown of heaps with excavatorDisposal of outputMechanical conditioning (e.g. screening) planned, but no experi-ence gathered, emplacement in sealed-base landfill via compac-tor
Photos
Local peculiaritiesPopular tourist area with pronounced differences in waste inci-dence between tourist season and off-season; community stret-ched out over more than 100 km; high transportation costs
Present state and activities to dateWaste treatment commenced in 05/00;All waste input treated since 03/02; privately operated, leachatequality and heap-teardown techniques tested on trial heap
Planned activitiesCompletion of leachate pond; investigation of leachate disposalat nearby sewage treatment plant
Project status
Technoscientific investigations and findingsExtensive test program to determine in-heap gas composition, temperature profiles, sampling of inputs and other material, analysisof leachate from treated, landfilled waste and from heaps
Particularities, remarks
The completed test heap
Landfill following conversion to MBWT (Bird's eye view)
Basic waste-management dataPopulation served: approx. 130,000Rainy season: May - Oct., annual precipitation approx. 1,350 mmAnnual waste input: 33,500 Mg (in 2001)Waste composition: 50- 60 wt.% organics
25 wt. % plasticsWater content: > 60 wt.%Plant capacity (of pilot project): 40 Mg/d, 14,600 Mg/a
73
Project characterization - Phitsanulok, ThailandProject designationPilot project Phitsanulok Thailand
Country, communityThailand, Phitsanulok
Beginning, endNovember 2001 - middle to end of 2003
CharacterPublic-private partnership
MiscellaneousLocal government intends to adopt the process on the basis ofprivatized waste treatment in the future
Partners in cooperationGTZ sector project "Promotion of Mechanical-biological Waste Treatment" Official contact Elke Hüttner; Division OE44; Phone: ++49 6196 79 0e-mail: [email protected]; Internet: www.gtz.de/mba/
Wilhelm Faber GmbH Wolfgang Tönges, Phone: ++49 6731 492 - 117e-mail: [email protected]; Internet: www.faber-ambra.de
Municipality of Phitsanulok, Thailand in cooperation with:Thai-German Solid Waste Management Programme for PhitsanulokPhitsanulok Municipal OfficeBaromtrilokanat Road, Muang District,Phitsanulok 65000, ThailandPhone ++66-55-232300, 232301 Fax ++66-55-232300e-mail: [email protected]; Internet: www.gtzth.org
DescriptionShort description of the project Pilot project for appraising the suitability of, and appropriately adapting, the FABER-AMBRA® process of Wilhelm Faber GmbH(non-mobile, passive ventilation, with mechanical pretreatment) for application in Thailand; transfer of process know-how via trai-ning and local backstopping
Employed technologyDelivery by collecting vehicle or container truckRegistration of weight and origin via truck weigher Conditioning/preparationManual presorting by waste pickers and possibly employeesHomogenizing drum, i.e. modified rotary drum vehicle from Ger -many, capacity: 7 MgHomogenization and comminution of waste inputEach batch takes 70 minutes, incl. 45 min for homogenizationDecompositionPreparation of heap base with pallets and drain pipesBuilding of heaps with excavatorCovering with biofilter, installation of watering system and sam-pling gaugesDecomposing time: 9 months; temperature-controlled processTeardown of heaps with excavatorDisposal of outputThin-layer emplacement by compactor (initial trials)
Local peculiaritiesWell-developed private recycling sector, large water and plasticsfractions, little structural material in residual waste
Present state and activities to dateWaste pretreatment commenced in 01/02 Three trial heaps on the old landfill, paved/reinforced waste-treatment area since 08/02; two test heaps
Planned activitiesDetermination of packed density, mass and volume analyses (inprocess) with decomposition lossesHydrological balance
Technoscientific investigations and findingsExtensive test program to determine in-heap gas composition, temperature profiles, sampling of inputs and other material, analysisof leachate from treated, landfilled waste and from heaps; analysis of decomposed material
Particularities, remarksSometime in 2003 the local government is expected to reach a decision on adoption of the process and to privatize operation ofthe landfill or pretreatment of the waste (MBWT) by way of competitive tendering.
Landfill entry point
Decomposing heap with coconut-shell biofilterProject status
Local integrationIntegration into the landfill environment Cooperation with the local GTZ project: "Solid Waste Management Programme for Phitsanulok"
Technical description Photos
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74
Project characterization - Al-Salamieh, SyrienProject designationAppropriate waste disposal for threshold and developing coun-tries
Country, communitySyria. Al-Salamieh
Beginning, endJan. 99 - end of 2002, early 2003
CharacterResearch project
MiscellaneousEstablishment of the process in Al-Salamieh within the scope ofthe PPP measure to follow this research project.
Partners in cooperationGTZ sector project "Promotion of Mechanical-biological Waste Treatment" Official contact Elke Hüttner; Division OE44; Phone: +49 6196 79 0e-mail: [email protected]; Internet: www.gtz.de/mba/
University of Kassel, Civil Engineering Department, Waste TechnologyFaculty / Dr.-Ing. Aber MohamadPhone: +49 561 804 3954, e-mail: [email protected]
Solid Waste Treatment W.L. Gore & Associates GmbHLothar Deyerling Phone: +49 89 12 27 26e-mail: [email protected]
The Syrian Arab RepublicMinistry of Local AdministrationGovernorate of Hama, Salamieh Municipal Council
Description
Short description of the project Research project for investigating the suitability of, and for appropriately adapting, the Gore laminate process (force-ventilated,controlled-heap decomposition with inert semi-permeable laminate cover) as a technically uncomplicated, relatively inexpensive,easy to operate, quickly implementable waste treatment facility for the production and quality control of soil conditioners (com-post).
Local integrationIntegration into the waste sector and landfill environment, composting of biowaste, cooperation with local specialists and training of sector employees
Technical descriptionBasic waste-management dataPopulation served: approx. 125,000Rainy season: Oct. - April, precipitation approx. 300 mmAnnual waste input: 20,000 Mg (in 2001)Waste composition: 70 wt.% organics
10 wt.% plasticsWater content: > 60 wt.%Planned plant capacity: 40-50 Mg/d, 15,000 Mg/a (treatment of approx. 220 Mg in scale-model trial)
Employed technology Delivery: by collecting vehicleRegistration of weight and origin via truck weigher Conditioning/preparation: Manual presorting by waste pickersand possibly employeesHomogenization and comminution of the waste in a mobile com-minutor; planned: 10 Mg/h homogenizing drum made in SyriaDecomposition: Construction of channels for ventilation anddrainage / collection of leachate; manual setting up and tearingdown of heaps; inert, semi-permeable laminate cover; three-month composting process, controlled via temperature and oxy-gen level; use of excavator and wheel loader plannedDisposal of output: Mechanical conditioning (screening) andseparation of fine material as compost in the handling of bio-waste; otherwise disposal to landfill.
Local peculiaritiesWell-developed private recycling sector (waste pickers), largewater and plastics fractions; plastic bags, little structural materi-al in household waste; dryness; high organic fraction
Photos
Present state and activities to dateThe research project "Appropriate waste disposal for TC andDC" has been completed. Preparations for a PPP program forimplementation of residual-waste treatment incl. separation ofuseful compost fraction, is under way. Plant scheduled for com-missioning May 2003.
Planned activitiesConstruction and commissioning of waste-treatment facility, trai-ning program, public awareness-raising, use of compost outputin agriculture, scientific backstopping program
Technoscientific investigations and findingsExtensive test program to determine waste composition, temperature profiles, water content, ignition loss, nutrients and heavymetals, sampling of inputs and other material
Particularities, remarksThanks to forced ventilation and covering of the heaps, no watering was necessary for the duration of mechanical-biological treat-ment, because the evaporated water condensed on the inside of the laminate cover and dripped back onto the decaying material.
Cover and forced ventilation of heaps
Heap with ventilating elements (aerators)Project status
75
Project characterization - Atlacomulco, MexicoProject designationPilot project, Atlacomulco Mexico
Country, communityMexico, Atlacomulco
Beginning, endSeptember 2002 - August 2003
CharacterPublic-private Partnership
MiscellaneousAdoption of the process for the landfill by the local administra-tion envisaged within the framework of a commercial contract
Partners in cooperationGTZ sector project "Promotion of Mechanical-biological Waste Treatment" Official contact Elke Hüttner; Division OE44; Phone: ++49 6196 79 0e-mail: [email protected]; Internet: www.gtz.de/mba/
Faber Recycling GmbH Wolfgang Tönges Tel.: +49 6731 492 - 117e-mail: [email protected]; Internet: www.faber-ambra.de
Honorable Ayuntamiento de AtlacomulcoState of Mexico, Mexico
Secretaría de Ecología del Estado de México(State Ministry of the Environment) State of Mexico, Mexico
DescriptionShort description of the project Pilot project for introducing integrated waste management (recycling, composting, residual-waste treatment, landfill-ing) in applica-tion of the FABER-AMBRA® process of Wilhelm Faber GmbH (non-mobile, passively ventilated heaps, with mechanical conditio -ning) for waste treatment and compost production, transfer of know-how by training and local project backstopping, integration ofthe informal sector ("Pepenadores")
Local integrationIntegration of "Pepenadores" upon introduction of integrated waste managementCooperation with the local GTZ project "Decentralization of Waste Management in the State of Mexico"
Technical descriptionBasic waste-management dataPopulation served: approx. 50,000Rainy season: May - Oct., precipitation approx. 1,000 mmAnnual waste input: 20,000 Mg (estimated)Waste composition: 50- 60 wt.% organicsWater content: > 60 wt.%Planned plant capacity: 40 Mg/d, 12,000 Mg/a
Photos
Employed technologyDelivery by collecting vehicle and container truck;No registration of weight or origin of wasteConditioning/preparation Manual sorting by "Pepenadores" and possibly employeesHomogenizing drum as an individually modified rotary drummachine from Germany; capacity: 7 MgHomogenization and comminution of waste materialEach batch takes 70 minutes, incl. 45 min for homogenization DecompositionPreparation of biological treatment with pallets and drain pipesBuilding of heaps with excavatorCover with geofilter, manual irrigation, monitoring of gas, tem-perature and process waterPlanned decomposing time: 9 months, process control via tem-perature measurementsTeardown of heaps with excavatorDisposal of outputFirst, mechanical conditioning (e.g. screening): planned, but noexperience gained to date
Local peculiaritiesNo organic biofilter material available; use of slightly geogenousmaterial as cover for the heaps
Present state and activities to dateWaste treatment commenced in 11/ 02, three test heaps on an old leachate pond; new heaps put up innew grounds since 01/03.
Planned activitiesIntroduction of separate waste collection in certain parts of townto obtain mono-batches of biowaste for compost production
Technoscientific investigations and findingsExtensive test program to determine in-heap gas composition, temperature profiles, sampling of inputs and other material as of03/03 by CENICA (Mexico)
Particularities, remarks
First group of trainees
Building of the first heapProject status
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76
Project characterization - ColombiaProject designationPromotion of ecologically sound waste management in Colombia
Country, communityColombia, Greater Armenia Area, Quindío
Beginning, end1 Aug. 2001 - 31 Dec. 2002
CharacterPublic-private partnership, technical school, social project, Recicladores, Internet portal
Partners in cooperation
GTZ Centre for Cooperation with the Private SectorOfficial contact: Helma Zeh-Gasser; Phone ++49 6196 79 0e-mail: [email protected]
Ingenieurbüro für innovative Abfallwirtschaft (ia) GmbH, Werner Bauer ++49 89 18935-0e-mail: [email protected]
B.A.U.M. TRACOM Ltda, BogotáArmenia, Quindío, ColombiaURL: www.baumgroup.com; E-Mail: [email protected]
DescriptionShort description of the project Pilot project for implementing an integrated approach to sustainable development via theoretical and practical training in "integra-ted waste management" and "sustainable waste management". Establishment of a technical school. Planning/construction/opera-tion of a model MBWT facility, incl. practical training. Training of specialists to serve as trainers. Integration of the Recicladorescooperatives. Summarization and publication of experience gained via the Internet portal "ForumZ for Latin America" (www.foro-z.com).
Local integrationElaboration and provision of training; planning and implementation of a social project; goals include strengthening and stabilizationof democratic structures and of municipal self-administration.Permanent local project partners: Cámara de Comercio de Armenia, Servicio Nacional de Aprendizaje SENA Quindío, UniversidadEmpresarial Armenia
Technical descriptionTMB demonstration facility
Employed technologyDelivery by container truck, with registration of waste origin (hauling andcollecting routes) and weight (truck weigher)Receiving point Waste receiving, input check, registrationMechanical conditioning Coarse and fine sorting, screening(manual)Separation of interfering objects,pollutants and recyclables (manual)Comminution, homogenization (mixing drum)Weighing of all material fractionsBiological (aerobic) treatmentIndoor composting in bamboo composting bins;No active ventilationCollection of leachate and process waterMechanical post-treatmentScreening and, as necessary, post-composting
Basic waste-management dataNo separate collection of wasteNo waste treatment and landfilling to technical standardsHigh organic fraction ( ~ 70 wt.%)Temporary TMB demonstration facility with separation and com-post-ing of a) household waste, b) central market waste, and c)waste from gardens and parks
Photos
Local peculiaritiesDisposal of residual waste: ~15-20 % of material inputIntegration of Recicladores cooperatives, incl. trainingLack of overall waste-management strategyMunicipal dump (Armenia) soon to close (Dec. 2002), but noconcrete alternative plans to date.
Project statusPresent state and activities to dateThe project is completed.Design/implementation of Internet portals complete: www.foro-z.com (knowledge portal) and www.coltec.info (training portal) Planning/construction/commissioning of MBWT facility
Planned activitiesPlanned continuation of operation of the MBWT facility up toearly 2003 by students from SENA Armenia; attendant scientificinvestigations and training; planned continuation of coop. anddevelopment of new projects upon completion of GTZ project.
Technoscientific investigations and findingsEcological evaluation of the process (stocktaking); comprehensive analysis of temperature, leachate and compost;material-flow documentation for the generation of mass balances
Particularities, remarksDue to acute political tensions in Colombia the project has suffered substantial delays since the beginning of the year. Knowledgenetworking interconnection with the GTZ project REPAMAR (Latin American Network for Waste Management, based in Lima). Asthe project progressed, cooperation with Servicio Nacional de Aprendizaje SENA in Quindío, and with its professors and students,has deepened.
Indoor part of model facility
Bamboo composting bins
77
1. Gernod Dilewski
Infrastruktur & Umwelt, Professor Böhm und Partner
Julius-Reiber-Straße 17
D- 64293 Darmstadt
Phone: +49 (0)6151 / 81 30 0
Fax: +49 (0)6151 / 81 30 20
URL: www.iu-info.de
E-Mail: [email protected]
2. Abir Ismail
P.O. Box 34 880
Damascus
Syria
E-Mail: [email protected]
3. Gabriele Janikowski
IKW Beratungsinstitut für Kommunalwirtschaft GmbH
Bayenthalgürtel 4
D- 50968 Cologne
Phone: +49 (0)221 / 93 70 91 0
Fax: +49 (0)221 / 93 70 91 11
URL: www.ikw.de; E-Mail: [email protected]
4. Dr. Dirk Maak
Wilhelm Faber GmbH
Galgenwiesenweg 23-29
D - 55 232 Alzey
Phone: +49 (0)6731 / 492 114
Fax: +49 (0)6731 / 492 115
URL: www.faber-ambra.de
E-Mail: [email protected]
5. Dr. Aber Mohamad
University of Kassel - Waste Technology Faculty
Mönchebergstraße 7
D- 34125 Kassel
Phone: +49 (0)561 / 95 29 095
Fax: +49 (0) 561 / 95 29 098
URL: www.uni-kassel.de/fb14/abfalltechnik/
E- Mail: [email protected]
Postfach 34 880
Damascus Syria
E-Mail: [email protected]
6. Dr. Dieter Mutz
Basel University of Applied Sciences (FHBB)
Institute for Environmental Technology (IfU)
Fichtenhagstr. 4
CH- 4132 Muttenz
Switzerland
Phone: +41 (0)61 / 4674 568
Email: [email protected]
7. Dr. Anna Lúcia Florisbela dos Santos
Segunda Privada de Támesis 36
Condado de Sayavedra
52938 Atizapan de Z.
Edomex / México
E-Mail: [email protected]
8. Bernhard Schenk
Independent Engineer & Consultant
Planckstrasse 20 a
D-10117 Berlin
Phone: +49 (0)177 / 36 00 299
Fax +49 (0)30 / 208 16 37
9. Gregório Alziro da Silva
Rua Noronha Torrezão, n.742, ap. .602
Cubango, Niterói - RJ.
Brazil
Phone: +55 (0)21 / 710 2362
10. Joachim Stretz
Technischer Umweltschutz - Environmental Engineering
Graefestr. 4
D- 10967 Berlin
Phone +49 (0)30 / 814 923 95
Fax. +49 (0)30 / 814 923 96
URL: www.j-stretz.de; E-Mail: [email protected]
Appendix 2 List of Important Contacts
Team of experts
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78
List of Important Contacts
1. Federal German Ministry for Economic
Cooperation and Development - BMZ
Dr. Annette van Edig
Friedrich-Ebert-Allee 40
D- 53113 Bonn
Phone: +49 (0)228 / 535 3761
Fax.: +49(0)1888 / 535 3500
URL: www.BMZ.de
E-Mail: [email protected]
2. Federal German Ministry for Education and
Research - BMBF
Dr. Jürgen Heidborn
Bonn Office
Heinemannstr. 2
53175 Bonn - Bad Godesberg
Berlin Office
Hannoversche Straße 30
D- 10115 Berlin
Phone: +49 (0)1888 / 57- 3541
Fax: +49 (0)1888 / 57- 83601
URL: www.BMBF.de
E-Mail: [email protected]
3. Projeto Gestao Ambiental Urbana - GAU
Dr. Detlev Ullrich
Largo IBAM n° 1, Humaita
22271-070 Rio de Janeiro
Brazil
Phone: +55 (0)21 2535 3434
Fax: +55 (0)21 2526 2464
URL: www.gau.org.br
E-Mail: [email protected]
4. Prefeitura Municipal de São Sebastião
Secretaria de Meio Ambiente e Urbanismo
Secretário Sr. José Teixeira Filho
Rua Amazonas 13
Centro - São Sebastião - SP - 11600/000
Phone +55 (0)12/ 38926000
Fax. +55 (0)12 / 38922819
URL: www.saosebastiao.sp.gov.br
5.Prefeitura Municipal de Ilhabela
Secretaria Municipal de Meio Ambiente
Rua Pref. Mariano Procopio de
Araujo Carvalho no. 86
Barrio Pereque-Ilhabela
SP-Brasil-CEP 11630-000
Brazil
Phone: +55 (0)12 / 472 2200
ramal 147
URL: www.ilhabela.sp.gov.br
E-Mail: [email protected]
6. Municipality of Phitsanulok
Solid Waste Management Programme
for Phitsanulok
Dr. Walter Schöll
Phitsanulok Municipal Office, Muang District
Phitsanulok 65000
Thailand
Phone: +66 (0)55 / 23 23 00
Fax: +66 (0)55 / 23 23 00
E-Mail: [email protected]
7. Apoyo a la Gestión de Residuos Sólidos
Municipales en el Estado de México
Dr. Günther Wehenpohl
Parque de Orizaba No. 7; 7. Piso
Col. Del Parque
53390 Naucalpan
Estado de México
Phone / Fax: ++52 (0)55 / 5576-4417
E-Mail: [email protected]
8. B.A.U.M. TRACOM Ltda
Ignacio Navas
Carr 13 No. 96 - 82 of. 103
Bogotá D.C.
Colombia
Phone: +57 (0)315 / 301 92 94
Fax: +57 (0)1 / 636 30 87
URL: www.baumgroup.com
E-Mail: [email protected]
79
9. Knoten Weimar - International Transfer Center
for Environmental Biotechnology
Braunschweig Technical University
Leichtweiss Institute, Waste-management
Department
Prof. Dr.- Ing. Klaus Fricke
Dipl.-Ing. Heike Santen
Beethovenstraße 51 a
D- 38106 Braunschweig
Phone: +49 (0)531 / 391 3969
Fax.: +49 (0)531 / 391 4584
URL: www.bionet.net
E-Mail: [email protected]
10. Wilhelm Faber GmbH
Wolfgang Tönges
Dr. Dirk Maak
Galgenwiesenweg 23-29
D- 55 232 Alzey
Phone: +49 (0)6731 / 492 232
Fax: +49 (0)6731 / 492 283
URL: www.faber-ambra.de
E-Mail: [email protected]
11. University of Kassel
Waste Technology Faculty
Prof. Dr.-Ing. Arnd Urban
Dr.-Ing. Aber Mohamad
Mönchebergstraße 7
D- 34125 Kassel
Phone: +49 (0)561 / 95 29 095
Fax: +49 (0) 561 / 95 29 098
URL: www.uni-kassel.de/fb14/abfalltechnik/
E- Mail: [email protected]
12. Solid Waste Treatment W.L.
Gore & Associates GmbH
Lothar Deyerling
Hermann-Oberth-Str. 24
D-85640 Putzbrunn
Phone: +49 (0)89 / 4612 2726
Fax: +49 (0)89 / 4612 4 2726
E-Mail: [email protected]
13. Ingenieurbüro für innovative Abfallwirtschaft
GmbH; iA GmbH
Werner P. Bauer
Gotzinger Str. 48/50
D- 81371 Munich
Phone: +49 (0)89 / 189 35 0
Fax: +49 (0)89 / 189 35 199
URL: www.ia-gmbh.de
E-Mail: [email protected]
14. Sustainable Technologies, Building-Business
Consultants (TBW) GmbH
Hr. Hartlieb Euler
Baumweg 10
D- 60316 Frankfurt am Main
Phone: +49 (0)69 / 9435 070
Fax: +49 (0)69 / 9435 0711
URL: www.tbw-frankfurt.com
E-Mail: [email protected]
15. Ingenieurgemeinschaft Witzenhausen
IGW Fricke & Turk GmbH
Bischhäuser Aue 12
D- 37 213 Witzenhausen
Phone: +49 (0)5542 / 93 080
Fax: +49 (0)5542 / 93 08 20
E-Mail: [email protected]
16. INTECUS Dresden GmbH
Pohlandstraße 17
D- 01309 Dresden
Phone: +49 (0)351 / 318 23 14
Fax: +49 (0)351 / 318 23 33
URL: www.intecus.de
E-Mail: [email protected]
17. Faber Serviço Ltda.
Christiane Dias Pereira
Rua Duque de Caxias, 188
2° Piso - SALA 13
Centro - São Sebastião
São Paulo, 11600-000
BRASIL
Phone/Fax: +55 (0)12 38 93 10 12
E-Mail: [email protected]
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18. Wilhelm Faber GmbH
Maria Elena Mendoza
Galgenwiesenweg 23 - 29
D- 55232 Alzey
Phone/Fax: +52 (0)712 1228 127
E-Mail: [email protected]
19. Wilhelm Faber GmbH
Chaiwat Teankum Schlicht
Galgenwiesenweg 23 - 29
D- 55232 Alzey
Phone: +66 (0)1 820 52 76
Fax: +66 (0)55 21 79 35
E-Mail: [email protected]
20. Dr. Kornelia-Theodora Drees
Viktoriaallee 46
D- 52066 Aachen
Phone: +49 (0)241 / 997 997 87
21. Dagmar Diebels
Filmteam
Goffartstraße 44
D- 52066 Aachen
Phone: +49 (0)241 / 51 51 064
22. Technical University Hamburg
-Harburg - TUHH
Waste Management Section
Prof. Dr. Rainer Stegmann
Fr. Ina Körner
Harburger Schlossstrasse 36
D- 21079 Hamburg
Phone: +49 (0)40 / 42878 3154
23. IKW Beratungsinstitut für Kommunalwirt-
schaft GmbH
Gabriele Janikowski
Bayenthalgürtel 4
D- 50968 Cologne
Phone: +49 (0)221 / 93 70 91 0
Fax: +49 (0)221 / 93 70 91 11
URL: www.ikw.de
E-Mail: [email protected]
24. Infrastruktur & Umwelt, Professor Böhm und
Partner
Gernod Dilewski
Julius-Reiber-Straße 17
D- 64293 Darmstadt
Phone: +49 (0)6151 / 81 30 0
Fax: +49 (0)6151 / 81 30 20
URL: www.iu-info.de
E-Mail: [email protected]
25. Dr. Uwe Cusnick
Organization Consultant
Wehrhofstraße 1
D- 60489 Frankfurt
Phone: +49 (0)69 / 789 39 15
Mobil: +49 (0)179 / 699 29 15
E-Mail: [email protected]
81
List of references
[1] AEA Technology (1998): Options to reduce
methane emissions. Report to DG XI of the
European Comission.
[2] Zeschmar-Lahl B., Jager J., Ketelsen K., Lahl
U., Scheidl K., Steiner M., Heckmann A.:
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Deutsche Gesellschaft für Technische Zusammenarbeit (GTZ) GmbH- German Technical Cooperation -Dag-Hammarskjöld-Weg 1-5Postfach 518065726 Eschborn, GermanyTelephone: +49 (6196) 79-0Fax: +49 (6196) 79-1115Internet: http://www.gtz.de
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