Modern Techniques Modern Techniques of Energy Wood Production of Energy Wood Production

on Farmlandon FarmlandVolkhard Scholz and Thomas HoffmannVolkhard Scholz and Thomas Hoffmann

7th International Research and Development 7th International Research and Development Conference of Central and East European Conference of Central and East European Institutes of Agricultural Engineering(CEE AgEng) Institutes of Agricultural Engineering(CEE AgEng) Minsk/Belarus, 8-10th June 2011Minsk/Belarus, 8-10th June 2011

1.1. IntroductionIntroduction2.2. Planting machinesPlanting machines3.3. Harvesting machinesHarvesting machines4.4. Clearing machinesClearing machines5.5. Storage of chipsStorage of chips6.6. Production costsProduction costs7.7. Summary Summary

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Energy wood from farmlandShort Rotation Coppice

High stable yields (poplar 10 tDM/ha/y)in spite of low expenses(1 x plant, >20 y utilize)

No or small application ofnitrogen and pesticides. Few contents of pollutantssuch as N, S, Cl, K etc.

Environmentally friendly production (N2O-Emissions).

Decontamination of soil from heavy metals (Cd, Zn).C-sequestration in soil.

Favourable harvest time (Dec...Feb.)Eligible harvest intervaldep. on market (1...20 y)

Set aside land subsidies 30...40 €/tDM or energy crop subsidies 4...6 €/tDM

Application of up-to-date environmentally friendly wood boilers!!!

SRC wood is a „new“ anda promising biofuel.

PoplarWillow

SRW = SRC = Short Rotation Coppice = Fast growing treesSRW = SRC = Short Rotation Coppice = Fast growing trees

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PlantingPlanting

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Planting shoots of poplar and willow

Photo: Hofmann, ISB Photo: Hofmann, ISB Photo: Lorbacher, ATB Photo: Lorbacher, ATB Photo: Scholz, ATBPhoto: Scholz, ATB

Source: Hofmann&Scholz, 2008

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Various planter types

Fröebbesta Fröebbesta Planter, Planter, Fa. Bo FranzenFa. Bo Franzen Photo: State University of New YorkPhoto: State University of New York

Mod. Sugar Cane Planter, Mod. Sugar Cane Planter, Fa. Henriksson Salix AB,Fa. Henriksson Salix AB, Photo: Henriksson S.Photo: Henriksson S.

Step Planter, Step Planter, Fa. Salix Maskiner ABFa. Salix Maskiner AB Photo: Lorbacher, ATBPhoto: Lorbacher, ATB

Energy Planter, Energy Planter, Fa. Egedal MaskinfabrikFa. Egedal Maskinfabrik, , Photo: Lorbacher, ATBPhoto: Lorbacher, ATB

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Favourable planting distances between rows

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HarvestHarvest

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Main SRC harvest lines

Chainsaw

Forestharvester

Log

lin

es

Felling bundler

Self-propelledrod cutter (bundler)

Tractor-trailedrod cutter (bundler)

Rod

lin

es

ChainsawTractor-mountedsaw

Tractor-mountedcutter chipperCutter unit forforage harvester

Ch

ip lin

es

1 phase

2 phases

intermitt.

contin.

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Cutter-chippersfor single-phase chip lines (< 5 y)

Modified Sugar Cane Modified Sugar Cane Harvester Austoft 7700Harvester Austoft 7700of Case Co. of Case Co. Photo: Burger, LWFPhoto: Burger, LWF

SRC Cutter Unit HS-2 of SRC Cutter Unit HS-2 of forage harvester Claas Co.forage harvester Claas Co. Photo: Scholz, ATBPhoto: Scholz, ATB

SRC Cutter Unit Woodcut 750SRC Cutter Unit Woodcut 750of forage harvester Krone Co.of forage harvester Krone Co.Photo: Scholz, ATBPhoto: Scholz, ATB

Tractor-mounted Cutter ChipperTractor-mounted Cutter Chipperfor conventional tractors for conventional tractors Photo: Ehlert, ATBPhoto: Ehlert, ATB

CurrentCurrentprototypeprototypeof ATBof ATB

Mod. sugar cane harvester

Special cutter units for forage harvesters

Tractor-mounted cutter chiper

Development status - Prototype Small series R&D, Prototype

Dead weight kg 12,500 1,300 1,200

Basic machine - Cane harvester Forage harvester1) Farm tractor2)

Power requirement kW 216 245 80

Weight of basic machine kg s. above 10,800 4,000

Number of rows - 2 2 1 or 2

Row spacing3) m 0.75 + 1.4 0.75 + 1.5 0.9

Cutting diameter mm < 70 < 70...100 < 120

Mean chopping length mm > 80 5 ... 40 50 ... 100

Mass throughput4) (PPT) tDM/h ≤ 20 ≤ 30 ≤ 15

Working rate4) (PPT) ha/h 0.2 ... 0.6 0.5 ... 1.3 0.2 ... 0.5

Working rate4) (ET) ha/h 0.1 ... 0.4 0.3 ... 1.0 0.1... 0.4

1) Standard forage harvester with forest tyres and special header, partly with reinforced drum, header hydraulics and underbody protection.2) Standard tractor with front or rear pto shaft and 3-point front suspension. 3) The second summand states the distance between adjacent twin rows. The mounted cutting chipper can where applicable also be used to harvest twin rows, however where row spacing is < 1.0 m only with appropriate tyres. 4) Valid for primary processing time (PPT) or execution time (ET).

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Technical data of promising cutter-chippers for single-phase chip lines

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ClearingClearing

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Machines removing stumpsConventional forestry machinery

Uprooting machine 1, Typ 2200overgroundFa. Schmidt, Uchte

2,2 m width50 mm deep150 kW1 ha/h (T1)7000 St./ha

1

Uprooting machine 2undergroundFa. Schmidt, Uchte

2,5 m width250 mm deep83 kW1 ha/h (T1)7000 St./ha

2

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Results of clearingPoplar parcell after 13 weeks

26.05.2004

24.04.2004

29.01.2004

0

100

200

300

400

500

600

<50 51-100 101-150 151-200 201-250 251-300 >300

Length class (mm)

Dry

mat

ter

(g/m

²)

Different Rows Inside

Different Rows Center

Different Rows Qutside≤ 100 mm deeply

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StorageStorageof chipsof chips

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Impact of chip size on storage of SRC chips in not ventilated piles

0

10

20

30

40

50

60

Wa

ter

co

nte

nt

an

d D

M lo

ss

(%

)

1.0E+02

1.0E+03

1.0E+04

1.0E+05

1.0E+06

1.0E+07

1.0E+08

Mo

ld f

un

gi

(cfu

/g F

M)

Thermophilic fungiWater contentDry matter loss

FineFinechipschips

16 - 22 mm16 - 22 mm

CoarseCoarsechipschipschipschips

56 - 63 mm56 - 63 mm

(Coarse)(Coarse)chunkschunks

120 - 156 mm120 - 156 mm

Energy loss

n = 10 n = 4 n = 5

MinMin

MaxMax

MeanMean

25 % DM loss p.a.!

n piles and/or silos of 1.5 to 45 m³ 120 to 360 days

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CostsCosts

0102030405060708090

100110120130140

Co

sts

(€

/t DM)

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Supply costs of storaged SRC wood chips

2a 2a4a 4a

Tractor-mountedcutter chipper

Forage harvesterwith SRC cutter

Willow

2a 2a4a

Poplar

Tractor-mountedcutter chipper

F. harv.w.SRC c.

8a

Manualharvest

Wood chip priceincl. VAT, Average 2010(C.A.R.M.E.N. 2010)

TransportHarvestFertilizationPlanting & ClearingLease

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Summary

During the past 30 years a multitude of machines for planting and harvesting of short rotation coppices (SRC) were developed and tested in Europe. However, caused by the low need, only a few of them exceeded the prototype stage.

There are three harvesting lines: log, rod, and chip lines. The latter are the cheapest but cause problems in long-term storage, particularly dry matter losses and mold fungi development in unventilated piles.

Best chances in future will have rod cutters as well as special cutter units for conventional forage harvesters and cutter-chipper units for conventional farm tractors.

The latter being else in R&D stage will have lower working rates, however, they are cheap and lightweight and offer the opportunity to produce well-storable chips > 50 mm and to harvest big poplars up to 5 years.

The supply costs of SRC chips range between 45 and 90 €/tDM and are significantly lower than the current wood chip price in Germany.

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Thank youThank you

E-Mail E-Mail volkhard.scholz@gmx.devolkhard.scholz@gmx.de

thoffmann@atb-potsdam.dethoffmann@atb-potsdam.de

СПАСИБОСПАСИБО ! !