The document discusses the TCR®-process developed by Fraunhofer UMSICHT as an add-on for anaerobic digestion (AD) plants to help with digestate management challenges. The TCR®-process uses pyrolysis and reforming at 350-750°C to convert digestate into high-value biochar, syngas, and oil. This allows for the reduction of substrate quantities in AD by at least 10% while increasing efficiency. It also facilitates nitrogen removal from the liquid digestate phase and production of fertilizing biochar. The process provides opportunities to potentially achieve over £100 per tonne from improved digestate treatment and valuable product generation.

1. Folie 1
© Fraunhofer UMSICHT
Digestate management with the
TCR®-process – add-on for AD plants
ADBA R&D Forum 2015
14-15 April 2015 Southampton
Andreas Weger, Rolf Jung, Fabian Stenzel, Andreas Hornung
Fraunhofer UMSICHT, Institutsteil Sulzbach-Rosenberg

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© Fraunhofer UMSICHT
Our motivation …
Energy conversion and storage
Raw and functional materials

3. © Fraunhofer
Agenda
 Motivation
 TCR®-process
 Efficiency increase of AD plants
 Digestate management
 Conclusion

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Motivation

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Motivation
New challenges for AD plants in Germany
 Amendment of the Renewable Energy Act (EEG 2014)
 Upcoming amendment of the Fertiliser Ordinance
 Recycling competition between manure and digestate
 Efficiency increase possible through
 Reduction of substrate quantity
 Nitrogen removal in digestate (liquid phase)
 Further value chain increase
 Carbon-rich char valuable fertilizer (Taylor-made fertiliser)
 Oil as possible fuel blend

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TCR®-process

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© Fraunhofer UMSICHT
TCR®-process
Process description
 Pyrolysis with integrated reformer unit
 Temperature: 350 - 450 °C / 550 - 750 °C
 Feed: organic residues from AD or bioethanol plants
 TCR®-process converts organic residues into high-value products
 Bio-Char (material or energetic usage)
 Syngas/Oil (energetic usage)
 Only solid digestate phase necessary
 Fertilizer effect remains (liquid phase)
TCR®-
process

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© Fraunhofer UMSICHT
TCR®-process
Process scheme
Pre-treatment Fermentation
Biomass
Dewatering
Gas
Digestate
.
Char
TCR® CHP
Power
Heat
Thermal drying
Oil
Digestate

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TCR®-process
Elementary analysis and heating value (HHV)
Bio-Char Oil Syngas
C 55 wt.%
H 2 - 3 wt.%
N 0,5 - 5 wt.%
S 0,5 wt.%
O 20 wt.%
Ash 15 wt.%
HHV 22 MJ/kg
C 50 - 70 wt.%
H 8 - 10 wt.%
N 2 - 5 wt.%
S 0,5 - 2 wt.%
O 9 - 11 wt.%
Ash 0,2 wt.%
HHV 31 MJ/kg
H2 30 - 40 v/v%
CO2 20 - 30 v/v%
CO 10 - 20 v/v%
CH4 4 - 8 v/v%
CxHy 5 - 10 v/v%
HHV 14 MJ/kg

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TCR®-process
Product yields

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Efficiency increase of AD plants

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© Fraunhofer UMSICHT
Efficiency increase of AD plants
Reduction of substrate quantity
489 m³ i.N./h
AD plant 1 MWel
Substrate (Mix) 24.000 Mg/a
Operating hours 8.000 h/a
Biogas:
Gross Energy 20.426.412 kWh/a
Biogas 3.909.900 m³ i.N./a
489 m³ i.N./h
CH4-Yield 52,4 v/v%
CO2-Yield 47,6 v/v%
Heating value 5,22 kWh/m³ i.N.
Density 1,32 kg/m³ i.N.

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© Fraunhofer UMSICHT
Efficiency increase of AD plants
Reduction of substrate quantity
Digestate
170 kg/h
85% DM
60 m³ i.N./h
TCR®
Syngas:
Gross Energy 1.872.661 kWh/a
Heating value 3,92 kWh/m³ i.N.
Density 1,02 kg/m³ i.N.
Mix Gas:
Gross Energy 20.607.586 kWh/a
Density 1,28 kg/m³ i.N.
 Reduction of substrate quantity ≥ 10% possible!
Substrate (Mix) 21.600 Mg/a
Operating hours 8.000 h/a
Biogas:
Gross Energy 18.734.925 kWh/a
Biogas 3.586.126 m³ i.N./a
448 m³ i.N./h
CH4-Yield 52,4 v/v%
CO2-Yield 47,6 v/v%
Heating value 5,22 kWh/m³ i.N.
Density 1,32 kg/m³ i.N.
508 m³ i.N./h
AD plant 1 MWel

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Digestate management

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Separation
fester Gärrest
flüssiger Gärrest
Input
24.000 Mg/a
18.100 Mg/a
TS = 9,8%
5.030 Mg/a
TS = 25%
13.070 Mg/a
TS = 4%
Digestate management
Example nutrient balance
N P
6 2,5 kg/Mg
109 45 Mg/a
N P
4,5 3,6 kg/Mg
23 18 Mg/a
N P
6,6 2,1 kg/Mg
86 27 Mg/a
 80% of nitrogen remains in the liquid phase [P as P2O5]
Solid phase
Liquid phase
Digestate
separation

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Digestate management
Nitrogen removal
Output Char
N-enriched
Output liquid phase,
low nitrogen amount
Input liquid phase
Input Char

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Conclusion

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Conclusion
Can you get £100 per tonne from digestate?
 Reduction of substrate quantity
 Cost reduction ≈ 80.000 €/a in the case of energy crops (in Germany)
 Nitrogen Removal
 Lower demand of arable land, transport costs  depends on situation
 Bio-Char
 Soil fertiliser (up to 600 € per tonne; Source: Sonnenerde.at)
 Oil
 Possible fuel blend

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Thank you for your attention!
Contact:
Fraunhofer UMSICHT
Institutsteil Sulzbach-Rosenberg
An der Maxhütte 1
92237 Sulzbach-Rosenberg
E-Mail: info-suro[at]umsicht.fraunhofer.de
Internet: http://www.umsicht-suro.fraunhofer.de
M. Eng. Andreas Weger
Telefon: 09661-908-434
E-Mail: andreas.weger[at]umsicht.fraunhofer.de
Prof. Dr. Andreas Hornung
Telefon: 09661-908-403
E-Mail: andreas.hornung[at]umsicht.fraunhofer.de
Digestate management with the
TCR®-process – an add-on for AD plants