210 likes | 354 Views
Can we produce biofuels without affecting food production and the environment?. The World Food Prize, Oct. 19, 2007 Birgitte K. Ahring BioCentrum-DTU & BioGasol www.biogasol.com. Statement from US Department of Energy. Bioethanol – Production technologies. Current technology:
E N D
Can we produce biofuels without affecting food production and the environment? The World Food Prize, Oct. 19, 2007 Birgitte K. Ahring BioCentrum-DTU & BioGasol www.biogasol.com
Bioethanol – Production technologies Current technology: Starch-based ethanol Biomass: Corn, grain, sugar The future technology: Lignocellulose based ethanol Biomass: Corn stover, straw, bagasse, wood etc.
In 2050 there will be 50% more people and 50% more cars in the world! = ? We need 232 kg of corn to make 50 liter of ethanol
glucose Feedstock- Three major components Lignin 5-25% Cellulose 35-45% Yeast / BG1 Hemicellulose C6 sugar 25-40% Ethanol C5 sugar BG1 xylose, arabinose, galactose, mannose, glucose.
2nd generation Pilot Plant in operation • Sustainable integrated ethanol concept • Continuous operation since August 2006 • Feedstock evaluations • Feasibility studies
Optimized use of the biomass Oxidized in the pre-treatment Organic material in the process water 3% 5% Biogas 19% Ethanol from SSF 35% Lignin for combustion 19% 20% Ethanol from pentoses Mass balance based on COD
Maxifuel Energy Balanceη=0.69 19 % Loss 3 % 15 % Biogas 12 % 12 % CHP-for the plant Biomass to Ethanol 26 % Lignin Straw 100 % 66 % 39 % Ethanol 1 % H2 Net effective use of energy content in wheat straw: 69 %
Demonstrate plant flexibility Manure with fibres Energy crops Grasses Wet wheat straw Fibres Garden waste Ethanol Hydrogen (Fuel Cells) Solid fuel Methane (CHP)
Bioethanol anlæg, Bornholm Situationsplan, eksempel
Separation Distillation Full Scale Plant 440.000 ton Wet oxidation Biomass C6 Fermentation Ethanol plant Salt removal Bio-pellets 180.000 ton C5 Fermentation Hydrogen 4 Mn Nm3 Ethanol 100 Mn litres Power 21.4 Mn Nm3 Methane Anaerobic Digestion Heat
3.5 The Techno-Economical Model Mass balance Flows Energy balance Operation costs (Externalities) Equipment specifications 0.30 USD per litres for 100 mn litre plant (biomass 55 USD per ton) Total Capital Investment Production cost
Plants convert sun light, water and CO2 into new plant material: biomass One hectare receives 10000 Mwh input of sun light per year
What you harvest depends on what you grow Grasses like sugar cane has high efficiency for harvesting sun light C4 C3
The solution- we harvest what we plant Corn isnot the future crop for fuel- 10 Gallons of ethanol consumes the energy of 7 Gallons of gasoline with little greenhouse gas reductions. New energy crops could mean that 3.5% of the earth surface is sufficient for growing the earth energy demand. Today we use 13% for agriculture. (Chris Somerville) A suitable crop would be a perennial prairie grass with little water need. 49 mill acres could supply 139 billion gallons of ethanol in year 2030. Farmers will be better off, the world would be less dependent of oil and we will take a giant step in greenhouse gas reduction. (Vinod Khosla)
PROCESS END USE Biofuel (good) CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 Biofuel (bad) Crude Oil (avg.) CO2 CO2 CO2 CO2 CO2 CO2 CO2 Tar Sands CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CTL CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2 CO2