01 biogazeurope 26 oct optimisingefficiency fraunhoferinstitute
TRANSCRIPT
Improving the efficiency of biogas plants Improving the efficiency of biogas plants by the introduction of innovative processesprocesses
André Wufka , Biogaz Europe, 26.10.11, Nantes, France
© Fraunhofer
Improving the efficiency of biogas plants by the introduction of innovative processes
Agenda
Fraunhofer IKTS in profile
Crucial points for improvement the efficiency in biogas production
Lignocellulose – structure and degradation
Disintegration methodsDisintegration methods
Conclusions
© Fraunhofer
André Wufka
Fraunhofer IKTS in profile
Business units
Structural ceramics Functional ceramics
Materials Sintering / Characterization Micro and energy systems
Smart materials and systemsProcesses / Components Environmental Engineering and Bioenergy
© Fraunhofer
André Wufka
Environmental Engineering and Bioenergy
Services offered
Analytical determination biogas potentials of substrates
Nutrient and trace elements application in digestion processes
Design of digestion processes; proof of profitability
Monitoring and performance tests of installed biogas plants
System development in the field of biogas purification and digester System development in the field of biogas purification and digester effluent treatment
Technical equipment – investigations from lab to market
© Fraunhofer
André Wufka
Fraunhofer IKTS in profile
Environmental processing technology Functional / Structural ceramics
Using the synergy potentials
Environmental Engineering and Bioenergy
Structural ceramics
DECONDIS™ - Process
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André Wufka
Crucial points for improvement the efficiency in biogas productionproduction
Substrates Substrate- Fermentation Biogas Biogas pretreatment purification utilisation
Wastes (industries, agriculture,
Milling Stirringperformance
Purification CHPg ,
municipalities)
Lignocellulosic materials
Comminution
Disintegration
Hydrolysis
p
Mixing technics
Additives (enzymes, trace
Desulphurization
Drying
Upgrading
Fuel cells
Heat use
Feed in to gas grid
Manure
Cultivationmethods energy-crops
y y
Deconservation
(enzymes, traceelements)
Measurement andcontrol technologies
pg g
CO2-separation
Storage
g g
Biomethane – SNG
Fuel
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André Wufka
crops technologies
Substrates – for biogas production
Organic waste Straw Leaves
Sludges from paperindustry Grass silage
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André Wufka
Lignocellulose – structure and composition
© Fraunhofer
André Wufka
Source: E.M. Rubin Nature 454
Lignocellulose – degradation
Requirement for biochemical degradation
Monomers (soluble in water)
Hemicellulose
Monomers (soluble in water)
Problem
on nat ral a onl er slo l Cellulose
Lignin
Technical solution
on natural way only very slowly possible
Technical solutionSubstrate pretreatment
Aim
Increase in particel surface area
Dissolution of protective layers (esp. lignin) Increase availability
Support and realization of hydrolysisSource: Biomass Magazine (04/2008)
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André Wufka
Possibilities of substrate pretreatmentOverviewOverview
Disintegration
physical chemicalbiological
Enzymes Acid treatmentmechanical thermal electrokineticFungi
Separatehydrolysis
Shear
Collision
Hot-water
Heated steam
High-voltagebpulses
Alkaline treatment
Oxidation
Collision
Pressure
Heated steam
Steam explosion
Special case: Ultrasonication
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André Wufka
Mechanical pretreatmentPrinciplesPrinciples
Milling (pressure, impact) Cutting (shearing) Extrusion (pressure, bbi i di )rubbing, grinding)
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André Wufka
Mechanical pretreatment
Substrate
wet
RotaCut
Dissolver wetDissolver
Extruder
(source: vogelsang-gmbh)
(source: envitec-biogas)( g )
Bursting reactors
dry
Mills
dry
(source: huning-maschinenbau)
(source: www.bio-qz.de)
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André Wufka
Mechanical pretreatment
Invest costs: 500 kWel. – Biogas plant
Extruder
Di l
PrallBursting reactor
Mühlen
Dissolver
Mills
LochscheibeCutter
0 20.000 40.000 60.000 80.000 100.000
überschlägliche Investkosten ohne Einbindung für 500kW-BGA (EUR)Approx. costs of invest without installation (€)
© Fraunhofer
André Wufka
Mechanical pretreatment
Energy demand: treatment of 1t substrate (~33%DS)
Extruder
i l
PrallBursting reactor
Mühlen
Dissolver
Mills
LochscheibeCutter
0 2 4 6 8 10 12 14 16
Energiebedarf (kWh/ t Silage)Energy demand (kWh/tmass)
© Fraunhofer
André Wufka
Mechanical pretreatmentResultsResults
Biogas production in batch fermentation tests
300
350
zu)
Alder andlandscapingmaterial treated
200
250e
(Nl/
kg o
TRz
by Extrusion
kg
VS)
100
150
ez. G
assu
mm
eg
as
yie
ld(L
N/k
0
50
0 5 10 15 20 25 30 35
zufu
hrs
pe
Bio
g
0 5 10 15 20 25 30 35
Versuchsdauer (d)Erle unbehandelt Erle extrudiertLandschaftspflegematerial unbehandelt Landschaftspflegematerial extrudiert
Duration (days)
Alder untreated Alder extruded
Landscaping material untreated Landscaping mat. extruded
© Fraunhofer
André Wufka
Mechanical pretreatmentResultsResults
Biogas production in batch fermentation tests
600
700
Rzu
)
Wheat strawpretreated
400
500
600
me
(Nl/
kg o
TR/k
gV
S)
200
300
pez
. Gas
sum
mg
as
yie
ld(L
N/
0
100
0 5 10 15 20 25 30 35
zufu
hrs
pB
iog
0 5 10 15 20 25 30 35
Versuchsdauer (d)
Stroh unbehandelt Weizenstroh NaOH Weizenstroh zerkleinert
Duration (days)
Straw untreated Straw extruded
Straw treated with NaOH
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André Wufka
Mechanical pretreatmentBenefitsBenefits
Increase of biogas yield (methane yield)
Increase of efficiency of substrates
Improving the properties of the fermentation substrate
Reduction of viscosity
Reduce the required stirringReduce the required stirring
Improvement of mixing quality
Reducing the tendency for the formation of floating and sinking Reducing the tendency for the formation of floating and sinking layers
Reduce the risk of blockages in pipes and pumps
Reducing hydraulic retention time in anaerobic digesters
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André Wufka
Separate hydrolysisCH4, CO2red.
CO2, H2, H2S
Organic
acids
FermentationSlowly degradables
Hydrolysis
Acidogenesis
Acedogenesis
Methanogenesis
Increasing the biological digestion performance
Acceleration of the biochemical degradation by optimal conditions (Temperature pH value)(Temperature, pH-value)
Increasing process stability in fermentation, higher methane content
Energy losses during the hydrolysis step are low (inactive methanogens)
© Fraunhofer
André Wufka
Energy losses during the hydrolysis step are low (inactive methanogens)
Separate hydrolysisResultsResults
Example grass silage - influence of temperature
160
180
200Hydrolysegas Freisetzung gelöster StoffeRelease of dissolved substances
120
140
160
gT
RS
ub
str
at)
60
80
100
(%)
bzw
. (m
g/g
mg
/gD
S)
0
20
40
((%
) re
sp. (
0
CH4 (%) CO2 (%) H2 (%) CSB (mg/gTRSubstrat)
Org. Säuren (mg/gTRSubstrat)
55°C 75°C
COD Org. acids
(mg/gDS)
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André Wufka
Ultrasonication
Disintegration by ultrasound forced cavitationeffect
Treatment of sludges from municipal wasteTreatment of sludges from municipal wastewater treatment plants
Increase in biogas yield between up to 20%
Reducing costs for sludge dispolsal
No effect of lignocellulosic substrates but
degasification of digestate (20%)
DMS - Disintegration module system -DMS Disintegration module system an energy efficient and robust technical system developed by IKTS
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André Wufka
Conclusions
State of the art in the area of the substrate pretreatmentthe mechanical disintegration
Object specific evaluation of need of substrate pretreatmentObject-specific evaluation of need of substrate pretreatment
Biogenic residues with higher lignocellulosic content
Long-fiber materials (for example grass silage)Long fiber materials (for example grass silage)
Problems with stirring and mixing
Economical efficiency is to consider for each disintegration method and each biogas plant
The effects of these mentioned pretreatments is however veryThe effects of these mentioned pretreatments is however verydependent on the biomass composition and operating conditions
© Fraunhofer
André Wufka
If we knew what it was we were doing, it would not be called research, would it?
Alb t Ei t iAlbert Einstein
Thank you very much for your attention!
www.ikts.fraunhofer.de
[email protected]@ikts.fraunhofer.de
© Fraunhofer
André Wufka