The BioTown, USA Digester: One Piece of the BioEnergy System Mark Jenner Biomass Rules
Overview: BioTown Digester Drivers/motivators differ between farm manure digesters and the BioTown digester Reliance on the BioTown Technology Suite BioTown Digester has Challenges BioTown Digester has Benefits
Traditional Hog Production Feed + Hogs Hog House Hogs (revenue) + Manure (cost) Wastes are managed by minimizing costs - Best minimized costs = zero costs - Not the same as maximizing revenue
Hog-Manure Production Today Feed + Hogs Hog House Hogs (revenue) + Manure (revenue) Digesters are one way of adding value to manure - On-site source of feedstock - On-site transportation costs minimized
BioTown USA Goals: Moving Reynolds, Indiana from fossil to biomass energy… Conversion of liquid fuel utilization Replacement of electrical supply Replacement of natural gas supply
BioTown Power and Light The system or ‘Suite of Technologies’ Liquid biomass ⇒ Anaerobic digester (methane gas) Solid biomass ⇒ Gasifier (producer/syn gas) ⇒ Fast pyrolysis (liquid bio-oil, gas, char)
BioTown Digester Role Manure + Sewage + Stover + Paper BioTown Power & Light Gas (revenue) + Electric (revenue) + Liquid (revenue) + Nutrients (revenue) + Heat (revenue)
BioTown Digester Challenges Multiple feedstocks (manure, sewage) Community Digester (multiple sources, great transportation costs, biosecurity) Digester technology selection
Available Liquid Feedstocks (Max) Volume in = volume out
Available Liquid Feedstocks (Min) Minimum size digester is 12.6% of the volume of Maximum size digester.
Distance Traveled Adds Costs 9 mile radius 2 mile radius Monticello and Monon sewage solids travel 6 or 7 miles. Manure travels less than 2 miles
Effluent Benefits and Costs
Commercially-Available Digesters High-end, high organic digesters Commercial farm manure digesters Private, Industrial waste digesters Publicly-owned sewage digesters Returns/Efficiency $0 $(-) $(+)
On-site vs. Off-site Digesters On-Site Off-Site Hog HouseDigester Hog House Digester
On-site Lower transportation costs Less variability in feedstock quality Fewer biosecurity issues (-) size/scale effect on finished biomass Off-site Higher transportation costs More variability in feedstock quality Increased biosecurity issues (+) size/scale effect on finished biomass On-site vs. Off-site Digesters
BioTown Digester Benefits Multiple Conversion technologies – tune digester to other equipment: 3 kinds of gas, 1 gen set. 3 different operating temperatures (2,000 degrees; 1,000 degrees; and 100 degrees F) Revenue from Sales / tipping fees In-kind transfers of nutrients and liquid fuels
Conclusion: BioTown Digester Drivers/motivators differ between farm manure digesters and the BioTown digester Reliance on the BioTown Technology Suite BioTown Digester has Challenges BioTown Digester has Benefits