4th European Bioethanol Technology Meeting
Advantages of Decentralized Bioethanol Production at Biogas Plant Sites C. Lanzerstorfer, A. Jäger Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
Outline Introduction Biogas Plants Economic Situation of Biogas Plants Results Process Integration for Biogas and Bioethanol Plants Economic Results Outlook Future Research in this Field at FH Oberösterreich
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Biogas Plant Characteristics Mature technology for bio-energy production Potential for optimization (reduction of residence time, pretreatment of substrates, use of lignocelluloses) Competitive on small/medium scale Sustainability of local plants (short ways of transport) Robust operation – can be taught with reasonable amount of training to farmers
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Biogas Plant Statistics Number of plants in Austria
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Biogas Plant Flow diagram
Off-gas Electric power
Thermal energy (hot water)
Cogenerator Biogas
Biomass Digester Digested manure
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Biogas Plant Profitability Costs Biomass, harvesting, digestate spreading Maintenance, insurance, labour 13 years, 6% interest rate
Revenues Available el. power and heat after subtraction of consumption and demand of biogas plant
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Biogas Plant Profitability 705 k€ max. Revenues (100% heat utilization)
?
545 k€ Revenues for el. power
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Biogas Plant Profitability
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Biogas Plant Profitability
Off-gas Electric power
Thermal energy (hot water)
Cogenerator Biogas
Biomass Digester Digested manure
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Integrated Biogas - Bioethanol Plant Advantages Thermal energy from biogas plant can be utilized in bioethanol plant for fermentation and distillation All of stillage from the bioethanol production can be fed into the biogas plant as a substitute for renewable biomass Thermal energy
Biogas Plant
Bioethanol Plant Stillage
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Process Integration Proposed solutions in literature1
55% Reduction in power generation of BG-plant
1
Senn, T.: Die Produktion von Bioethanol als Treibstoff unter dem Aspekt der Energie-, Kosten- und Ökobilanz. Tagungsband Fachtagung Regenerative Kraftstoffe, Stuttgart 2003, 87-98 (2003) Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Process Integration Improved Integration Hot water from cogeneration unit is used for heating in fermentation Steam for distillation is produced from hot off-gas from cogeneration unit Produced bioethanol grade 92% (dehydration external 2) Size of bioethanol plant is determined with respect to maximum utilization of the available thermal energy from the biogas plant (no use of biogas or external fuel for heating purposes)
2
Wetter, C., Brügging, E. and Doetkotte, F.: Machbarkeitsstudie zur Absolutierung von Bioethanol aus landwirtschaftlichen Brennereien. Fachhochschule Münster, Steinfurt (2005) Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Process Integration Off-gas Bioethanol
Steam
Distillation
Stillage Off-gas
Thermal energy (hot water)
Fermentation
Electric power Hot water
Cogenerator Biogas
Digester Biomass
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
Digested manure
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Process Integration Digestion Experiments (VDI 4630)
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Process Integration Digestion Experiments (VDI 4630)
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Process Integration Digestion Experiments (VDI 4630)
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Integrated Biogas - Bioethanol Plant Plant Data Biogas plant:
500 kWel
(existing)
Substrate: renewable biomass (maize silage, CCM and some pig manure); renewable biomass partly replaced by stillage Bioethanol plant:
500 m³/a bioethanol
(virtual)
sized with respect to maximum utilization of the available thermal energy from the biogas plant; limiting parameter is the amount of steam produced from hot off-gas for distillation bioethanol 92% Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Integrated Biogas - Bioethanol Plant Energy Balance
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Integrated Biogas - Bioethanol Plant Profitability Calculation No cross-calculation costs for stillage and heat El. power consumption of bioethanol plant within operation costs of plant
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
page 19
Integrated Biogas - Bioethanol Plant Profitability 640 k€ max. Revenues (100% heat utilization*) 545 k€ Revenues for el. power
?
* 100% of remaining heat Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Integrated Biogas - Bioethanol Plant Profitability Costs Biomass, harvesting Maintenance, insurance, labour, el. power 10 years, 6% interest rate
Revenues Bioethanol
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Integrated Biogas - Bioethanol Plant Profitability
Min. required price for Bioethanol (92%): 0,80 € /l
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
?
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Integrated Biogas - Bioethanol Plant Total Economics Min. required price for bioethanol (92%): 0,60 € /l BIoethanol
940 k€
100% heat utilization
640 k€
Revenues for el. power
?
545 k€
Min. required price for bioethanol (92%) without additional heat utilization: 0,80 € /l Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Summary Integrated Biogas - Bioethanol Plants Break even can be calculated depending on substrate costs Costs for bio-energy production are comparable low for local/regional plants Central dehydration plants are necessary Demonstration plant required to convince authorities and local investors/producers
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Outlook Bioethanol „2nd“Generation – Utilization of Straw Thermo-mechanical pretreatment of straw (steam explosion) Enzyme production on pretreated straw (30°C) Hydrolysis of pretreated straw (50°C) Fermentation to ethanol
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Outlook
Future
Thank You for Your Attention ! Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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Outlook
Upper Austria Univ. of Applied Sciences, Faculty of Engineering and Environment Science
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