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Past practice in BC
3
Beehive burners
Sawmill waste (hog fuel) was burned without capturing heat value.
Now sawmill waste is burned to heat the dry kilns.
A “Darlek”
Forms of Energy
• Solid
• Liquid
• Gas
Bioenergy – drivers
• Climate change
• Shortages of traditional energy sources
• Costs of traditional energy sources
• Energy security
• Landfill reduction
• Mountain Pine Beetle (BC-specific)
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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
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Bioenergy – technology options
• Direct combustion
• Wood pellets
• Gasification
• Bio-diesel
• Bio-ethanol
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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)
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Wood Pellets
• Waste may be ground to consistent, fine size.
• Pellets are held together by natural “adhesive” in wood (lignin).
• Pellets are denser than starting material.
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Wood Pellet Stove
• 1 – Hopper• 2 – Convection fan• 3 – Auger• 4 – Ash pan• 5 – Igniter• 6 – Heat exchange tubes• 7 – Burn chamber
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www.pelprostoves.com/images/pelpro-cutaway.jpg
Pellet plants in BC
• 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
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Bioethanol from wood waste
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Wood Pre-treatment
Solid material
Sugars insolution
Solidresidue
AlcoholFermentation
Enzymes
Burn
Newproducts?
LIGNOCELLULOSE
Pretreatment
Fractionation
Fermentation
Recovery
EnzymaticHydrolysis
PentosesHexoses
Lignin
Cellulose
Hemicellulose
Extractives
BIOFUELS BIOENERGY
BIOPRODUCTS
STARCH
Pretreatment
Fractionation
Fermentation
Recovery
EnzymaticHydrolysis
Hexoses
SUGAR
Pretreatment
Fractionation
Fermentation
Recovery
Hexoses
Conversion of biomass sources
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
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Gasification
• Burns biomass with controlled amount of oxygen
• Converts biomass into carbon monoxide and hydrogen
• Results in “syngas” which is itself a fuel
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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)
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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
• Generation of steam and electricity
• Low pressure steam (15% reduction of natural gas used for heating)
• Electricity generation (2MW, demonstration scale)
• GHG reduction of 5,000 tonnes/year*26
Cogeneration plant
• William’s Lake, BC• Est. 1993• 60 MW capacity• Electricity feeds into
BC Hydro grid• Burns wood waste
(600,000 tonnes/year)• Five local sawmills provide wood waste
(combined capacity of 1 billion fbm)• High efficiency combustion
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Looking back and forward…??1700
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2020
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2100
Hydrocarboneconomy1800-2050
Industrial
revolution
Carbohydrateeconomy1990-21??
Biomass & renewables
Oil & GasCoal
Carbohydrateeconomy
??-1800
Agricultural-based
log (primary energy use) by category
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