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WOOD 120 Bio-energy. The “Bio-Buzzwords”. Bio-energy Bio-mass Bio-fuels Bio-diesel. Past practice in BC. Beehive burners. Sawmill waste (hog fuel) was burned without capturing heat value. Now sawmill waste is burned to heat the dry kilns. Forms of Energy. Electricity
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The “Bio-Buzzwords” • Bio-energy • Bio-mass • Bio-fuels • Bio-diesel
Past practice in BC Beehive burners Sawmill waste (hog fuel) was burned without capturing heat value. Now sawmill waste is burned to heat the dry kilns.
Forms of Energy • Electricity • Transportation fuel • Heat
Forms of Energy • Solid • Liquid • Gas
Fossil fuels (the simple slide) CO2 Fossil Fuels
CO2 Biomass Fossil Fuels Bioenergy (the simple slide) reduce
Bioenergy – drivers • Climate change • Shortages of traditional energy sources • Costs of traditional energy sources • Energy security • Landfill reduction • Mountain Pine Beetle (BC-specific)
Biomass – sources • Grain • Straw • Grass • Sugar cane (bagasse) • Wood (lignocellulose)
Wood vs. other cellulosic biomasses • Longer storage life and lower storage costs • Higher bulk density • Less intensive use of water and fertilizer in its growth • Established collection system exists
Energy density of materials GJ per unit
Bioenergy – technology platforms • Wood pellets • Gasification • Bio-ethanol • Direct combustion
Bio-fuel status in BC www.energyplan.gov.bc.ca
Wood Pellets • Sawmill waste extruded into small pellets. • Either burned directly for heat value or for generation of electricity • Used domestically (N.A.) and industrially (Europe)
Wood Pellets • Waste may be ground to consistent, fine size. • Pressed through pelletizer to consolidate. • Pellets are held together by natural “adhesive” in wood (lignin). • Pellets are denser than starting material.
Wood Pellet Stove 1 – Hopper 2 – Convection fan 3 – Auger 4 – Ash pan 5 – Igniter 6 – Heat exchange tubes 7 – Burn chamber www.pelprostoves.com/images/pelpro-cutaway.jpg
Pellet plants in BC (2011) • 8 plants • 787,000 tonnes production • Plant capacity56-186,000 tonnes • Used 2.2 million m3 of wood residues • 10% of global market
Liquid biofuels • Bio-ethanol (one example) • Currently produced from grain (in NA) • Blended with gasoline • Gasoline:ethanol 90:10 • Reduces carbon monoxide emissions
Bioethanol from wood waste Burn Solidresidue Solid material Enzymes Newproducts? Pre-treatment Wood Sugars insolution Alcohol Fermentation
Conversion of biomass sources SUGAR STARCH LIGNOCELLULOSE Pretreatment Pretreatment Pretreatment Fractionation Fractionation Fractionation Lignin Cellulose Hemicellulose Extractives EnzymaticHydrolysis EnzymaticHydrolysis Hexoses Pentoses Hexoses Hexoses Fermentation Fermentation Fermentation Recovery Recovery Recovery BIOFUELS BIOENERGY BIOPRODUCTS
Bio-ethanol from wood • Wood is hard to break downinto chemical components • High cost of enzymes • Products need to bedeveloped utilizing solid residue (lignin) • Rate of development of technology is influenced by price of oil
Gasification • Burns biomass with controlled amount of oxygen • Converts biomass into carbon monoxide and hydrogen • Results in “syngas” which is itself a fuel www.nexterra.ca/i_mages2/Gasifier.jpg
Gasification • Cleaner and more efficient technology than direct conversion of biomass • Syngas can be burned on site (for production of electricity) or transported (increase in energy density) http://www.sc.edu/usctimes/articles/2005-02/images/gasification.jpg
Gasification plant at UBC • Opened in September 2012 • 25,000 tonnes of urban wood waste per year from Metro Vancouver • Generation of steam and electricity • Low pressure steam (15% reduction of natural gas used for heating on UBC campus) • Electricity generation (2MW, demonstration scale) • GHG reduction of 5,000 tonnes/year*
Gasification plant at UBC Photo credits: Don Erhardt
Gasification plant at UBC (Nexterra)
Electricity generation Raw material ?
Cogeneration plant • William’s Lake, BC • Established in 1993 • 60 MW capacity • Electricity feeds into BC Hydro grid • Burns wood waste (600,000 tonnes/year) • 4-5 local sawmills provide wood waste (combined capacity of 1 billion fbm) • High efficiency combustion
Current Status of Bio-Energy Technologies Gasification
Bio-energy - issues • Government policies (e.g., tax credits? R&D incentives?) • Competing green technologies (e.g., wind, wave, geothermal) • Competing bio-energy technology platforms still being developed • Competing new fosil fuel capcaity in North America • Food vs. Fuel vs. Fibre