Preliminary study of diesel biodegradation mechanism in the food waste composting process
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Transcript of Preliminary study of diesel biodegradation mechanism in the food waste composting process
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Preliminary study of diesel biodegradation mechanism in the food waste composting process
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May 25-26, 2012
Li-Hsien Chen1, Guan-Yu Chen1, Guo-Huei Wang1, Der-Shyan Sheu2, Chitsan Lin1
1 Department of Marine Environmental Engineering, National Kaohsiung Marine University.2 Department of Marine Biotechnology, National Kaohsiung Marine University.
Email: [email protected]
2012 International Conference on Environmental Quality Concern, Control and Conservation (EQC 2012)
D e p a r t m e n t o f M a r i n e E n v i r o n m e n t a l E n g i n e e r i n g , N a t i o n a l K a o h s i u n g M a r i n e U n i v e r s i t y
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Research Background And Motivation
Materials And Methods
Research Purposes
Conclusions
Results And Discussion
OUTLINE
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Research Background
Source: Taiwan EPA (http://edw.epa.gov.tw/querySoilSite.aspx)
Pollution characteristicsNumber of
remediation sites
Soil and groundwater Heavy metal contaminated sites
Soil and groundwater organic contaminated sites
Soil and groundwater Heavy metal and organic contaminated
sites
(27 sites)
(79 sites)
(5 sites)
Total remediation sites111 sites (67 oil-related remediation
sites)
Oil pollution is a serious environmental problem in the past decades. According to the Taiwan EPA, there are 67 documented oil-related remediation sites in Kaohsiung.
Lin et al. (2012) reported an innovative mineral oil treatment technology. The other report that utilizing food waste thermophilic composting process to degrade 7,000 mg/kg of diesel contaminated soil in a scale of 10 tons. the diesel removal rate reached 90 % on Day 54.
The method has the following advantages:
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low costs
less secondary pollution
can be backfilled to the site
Rich nutrients
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Food waste composting processes to degrade diesel will produce the intermediate VOCs (Volatile Organic Compounds), while VOCs with the composting process, resulting in different types of compounds.
However, we still don’t know mechanism. If we know the mechanism, then we can control the VOCs from compost.
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Research Motivation
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This study was divided into two parts:
( A ) The VOCs of food waste composting process by
GC / MSD analysisUse of the airbags sampling with GC / MS analysis.
Features: analysis of 101 kinds of voc compounds at one
time.
( B ) Exploring the diesel oil biodegradation
mechanism in the food waste composting
process. 。
Research Purposes
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MATERIALS AND METHODS
Experimental Framework
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Food waste70kg
sawdust 15kg
mature compost 15kg
Compost pile
VOC sample collection
Analysis
Discussion
Moisture content
pH
Temperature
Basic parameters monitoring
Add 1kg diesel
Control pile
Experimental pile
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Compost Operational Procedures
Food waste weighing 70 kg was shredded to 1-cm particles. After mixed with 15 kg of sawdust (15%, w/w) and 15 kg of mature compost (15%, w/w).Water was added to maintain 50-60% moisture content. Temperature, moisture content, and pH were monitored during composting process.
Collection pool
Crusher Machine
Mixed
Sampling airbags
Soil Gas Sampling Design
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Compost,Sampling tubePump
Negative pressure box
•The day before sampling, buried sampling tube into compost。•Making the vacuum pump turns box into negative-pressure situation.•The compost gas (VOCs) was collected form outside to inside fill the sampling bag.
Sampling setup
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Analysis Equipment
Agilent 7890 GC
Agilent 5975N MSD
Entech 7100
Glass Bead Cryo
Tenax-TA Trap
Cryo Focus
Airbags
Entech 7100
Entech 7032Auto sample
Analytical instruments
Entech 7100Cryogenic preconcentration
Agilent 7890 GAS Chromatography (GC)
Agilent 5975 MSD
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RESULTS AND DISCUSSION
Alkanes Cycloalkanes Aromatics Alkenes Butane
Isopentane2,3-Dimethylpentane
2-Methylpentane3-Methylpentane
Hexane2,4-Dimethylpentane
2-Methylhexane2,3-Dimethylpentane
3-Methylhexane2,2,4-trimethylPentane
Heptane2-Methylheptane3-Methylheptane
n-OctaneNonane
n-Decanen-UndecaneDodecane
cyclohexaneMethyl-cyclohexane
BenzeneToluene
Ethylbenzenem,p-Xylene
Styreneo-Xylene
Isopropylbenzenen-propylbenzenem-Ethyltoluenep-Ethyltoluene
1,3,5-trimethyl-Benzeneo-Ethyltoluene
1,2,4-trimethylbenzene1,2,3-trimethylbenzene
m-Dieyhylbenzenep-Diethylbenzene
Propene1-Butene
Trans-2-ButeneCis-2-Butene
Isoprene1-Hexene
Sulfur Alcohols Carbonate ester Aldehydes Dimethyl sulfide
Dimethyl disulfideMethanethiolEthyl Alcohol
2-Butanol1-propanol-2-methyl1-Butaol,3-methyl
Acetic acid, methyl eaterEthyl acetate
Methyl propionaten-propyl acetate
Propanoic acid, ethyl esterButanoic acid, methyl
ester1-Butaol,3-methyl acetate
Propanal 2 methyl-Butannal,3-methylButanal,2-methyl-
Ketones BIO-VOC Amines 2-Propanone(Acetone)
2-Butanone(MEK)2,3-Butanedione
1R-.alpha.-pinene.beta.-pineneD-Limonene
Trimethylamine 15
The all VOCs of food waste composting processes to degrade diesel table
Total VOCs change during the compost process
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0 2 4 6 8 10 120
100
200
300
400
500
600
Time ( days )
Tot
al V
OC
s con
c. (
ppm
)
Temperature Rising Stage
Thermophilic Stage Temperature Recovering Stage
The initial of the composting produces the highest VOCs conc. , after rising stage shows a slow downward trend.
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The VOCs of scale during Temperature Rising and Thermophilic Stage
alkanes, 9.47% (5)
(4) (3)
alcohols, 21.34%
carbon-ate ester, 59.70%
(2) (1)
(1) Bio-voc(2) Ketones(3) Aromatics(4) Cycloalkanes(5) Alkene
Temperature Rising Stage
(4) (3) (2)
alcohols, 23.74%
(1) (6)
(5)
aldehydes, 5.95%
ketones, 25.03%
BIO-VOC, 27.26%
(1) carbonate ester(2) aromatics(3) alkene
Thermophilic Stage
(4) Alkanes(5) Amines(6) Sulfur
Alkanes Alkene Cycloalkanes Aromatics Alcohols Carbonate ester
Sulfur Amines Aldehydes Ketones BIO-VOC
Rising 9.47 0.35 1.47 1.63 21.34 59.70 0.75 5.01
Therm 4.67 1.75 0.02 0.47 23.74 4.33 4.65 2.14 5.95 25.03 27.26
0 2 4 6 8 10 120
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100BIO VOC
控制組 添加柴油
0 2 4 6 8 10 120
200
400carbonate ester
010203040
Alkanes
0102030
Sulfur
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The VOCs groups changes of food waste composting processes to degrade diesel
Tota
l Voc
s co
nc.
(ppm
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Time ( day )Time ( day )
Rising RisingThermophilic Stage
Thermophilic Stage
0
2
4
6
Alkenes
0246
Cycloalkanes
0
5
10 Aromatics
0204060
Ketones
0
100
200 Alcohols
0102030
Aldehydes
0
5
10Amines
After 1 day composting, the compost gas consists of alcohols and carbonate ester. The contribution of alcohols and carbonate ester may be from the fermentation of more biodegradable food waste or alkanes in the diesel.
On the 3th day, the compost gas emerges of thermophilic fermentation products these include ketones , aldehydes and sulfides. They may be from the alcohols and carbonate ester.
During the diesel composting process (day 0 to day 8), bio-VOCs were observed all the time; these include 1R-.alpha.-pinene, beta.-pinene and D-limonene.
The composition of initial compost gases includes alkanes, alkene, naphthenic class, and the aromatics. The main source of VOCs at this stage is from low molecule weight compounds within the diesel constituents.
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The VOCs compounds changes of food waste composting processes to degrade diesel
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n-OctaneMethyl-cyclohex-ane1-ButeneToluene
Tot
al V
ocs c
onc.
(pp
m)
0 2 4 6 8 10 120
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100
150
200
250
300
Ethyl acetateEthyl Alcohol
0 2 4 6 8 10 120
102030405060708090
Butannal,3-methyl
Time ( days )
1. The composition of initial compounds is n-Octane、Methyl-cyclohexane and Toluene
2. Dimethyl sulfide is the most common compounds in the composting process.
3. After 1 day composting, the compost gas consists of Ethyl acetate and Ethyl alcohol.
4. the compost gas emerges of thermophilic fermentation products these include Butannal, 3-methyl、 2-Butanone.
5. D-Limonene is the highest concentration of compound of BIO-VOC
Rising Thermophilic Stage Rising Thermophilic Stage
According to the above finding, we assume the mechanism as follows.
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The preliminary mechanism of diesel biodegradation
TPH Alkane Alcohol Ketone / Aldehyde Carboxylic acid
Sulfur Ester
Naphthenic class Alkene
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CONCLUSIONS
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There were 11 groups of VOC monitored in the diesel degradation process, consisting of alkanes, cycloalkanes, aromatics, alkenes, alcohols, carbonate ester, ketones, aldehydes, sulfur compounds, amines, and bio-VOC . The composition of initial compost gases includes alkanes (62.76%), alkene (8.41%), naphthenic class (13.86%), and the aromatics (4.78%). The main source of VOCs at this stage is from low molecule weight compounds within the diesel constituents. After 1 day composting, the compost gas consists of alcohols (21.34%) and carbonate ester (59.70%). The contribution of alcohols and carbonate ester may be from the fermentation of more biodegradable food waste or alkanes in the diesel.
(1)
(2)
(3)
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On the 3th day, the compost gas emerges of thermophilic fermentation products these include ketones (25.03%), aldehydes (5.95%) and sulfides (4.65%).
During the diesel composting process (day 0 to day 8), BIO-VOCs were observed all the time; these include 1R-.alpha.-pinene, beta.-pinene and D-limonene.
During the entire diesel composting process, we also identified many organic acids which were assumes as the end products of aerobic biodegradation.
(4)
(5)
(6)