WOOD 120 Bio-energy
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Transcript of WOOD 120 Bio-energy
WOOD 120
Bio-energy
1
The “Bio-Buzzwords”
• Bio-energy
• Bio-mass
• Bio-fuels
• Bio-diesel
2
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.
Forms of Energy
• Electricity
• Transportation fuel
• Heat
4
Fossil fuels (the simple slide)
6
CO2
Fossil Fuels
Bioenergy (the simple slide)
7
CO2
Fossil Fuels
Biomass
reduce
Bioenergy (the more complicated slide)
8
Bioenergy – drivers
• Climate change
• Shortages of traditional energy sources
• Costs of traditional energy sources
• Energy security
• Landfill reduction
• Mountain Pine Beetle (BC-specific)
9
Biomass – sources
• Grain
• Straw
• Grass
• Sugar cane (bagasse)
• Wood (lignocellulose)
10
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
11
Transportation
12
Energy density of materials
13
GJ
per
unit
Bioenergy – technology platforms
• Wood pellets
• Gasification
• Bio-ethanol
• Direct combustion
14
Bio-fuel status in BC
15www.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)
16
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.
17
Wood Pellet Stove
1 – Hopper
2 – Convection fan
3 – Auger
4 – Ash pan
5 – Igniter
6 – Heat exchange tubes
7 – Burn chamber
18
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
20
21
Wood Chemistry
WOOD
Holocellulose Lignin(s) Extractives Ash
Cellulose Hemicellulose(s)
Bioethanol from wood waste
22
Wood Pre-treatment
Solid material
Sugars insolution
Solidresidue
AlcoholFermentation
Enzymes
Burn
Newproducts?
Comparsion of bio-fuel feedstocks
23
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
25
Gasification
• Burns biomass with controlled amount of oxygen
• Converts biomass into carbon monoxide and hydrogen
• Results in “syngas” which is itself a fuel
26
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)
27
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*
28
29
Gasification plant at UBC
Photo credits: Don Erhardt
Gasification plant at UBC
30
(Nexterra)
Electricity generation
31
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
32
Looking back and forward…??1700
1740
1780
1820
1860
1900
1920
1940
1960
1980
2000
2020
2040
2060
2080
2100
Hydrocarboneconomy1800-2050
Industrial
revolution
Carbohydrateeconomy1990-21??
Biomass & renewables
Oil & GasCoal
Carbohydrateeconomy
??-1800
Agricultural-based
log (primary energy use) by category
Current Status of Bio-Energy Technologies
34
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