Biomass Inventory and Distributed BioPower Production in Manitoba

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Biomass Inventory and Distributed BioPower Production in Manitoba Dr. Eric Bibeau Mechanical & Industrial Engineering Dept Manitoba Hydro Chair in Alternative Energy Gasification Workshop, Gimli, Manitoba, September 30, 2004

OUTLINE Biomass availability in Manitoba Biomass availability & biopower transportation feedstock analysis plant scale conversion/revenue charts Conclusions

Biomass Inventory to Support Manitoba Biomass Economy Bio-Energy fuels power heat Industrial chemicals Fibre Feed Drivers GHG Energy supply Innovation Rural development Air quality Products

Biomass for BioPower in Manitoba Forest biomass wood residues from sawmills Agriculture residues straw from grain Energy crops Animal wastes swine, poultry, bovine Municipal wastes organic residues Non-mainstream biomass cattails and peat moss Biomass Waste Streams Forest Agriculture Municipal

Biomass Feedstocks Measurements BDT ODT AR Wet/Dry Ultimate analysis Proximate analysis Heating value Biomass is nature s way of storing solar energy Waste Wood Dry Wet Carbon 49.91% 24.96% Hydrogen 5.93% 2.97% Nitrogen 0.34% 0.17% Sulfur 0.04% 0.02% Chlorine 0.01% 0.01% Oxygen 42.35% 21.18% Ash 1.42% 0.71% Moisture (H2O), (AR) Biosolids 50.00% Dry Wet Carbon 32.60% 19.56% Hydrogen 4.71% 2.83% Nitrogen 5.13% 3.08% Sulfur 1.60% 0.96% Chlorine 0.12% 0.07% Oxygen 16.34% 9.80% Ash 39.62% 23.77% Moisture (H2O), (AR) 40.00% Waste Wood Volatile (dry) 55.5% Fix carbon (dry) 24.5% Ash (dry) 20.0% Moisture (AR) 30.0% LHV MJ/kg Biomass 19.7 MJ/kg Hydrogen 119.5 MJ/kg Coal 25.5 MJ/kg

Forest Biomass TPF: Timber productive forest region where biomass is available for use Merchantable biomass tree stem Non-stem biomass bark, branches, leaves ACC: Annual allowable cut yearly merchantable tree volume taken from TPF Actual harvest yearly amount actually taken

Forest Biomass Wood residues actual harvest merchantable wood = wood residues Wood residue applications secondary manufacturing chips for pulp cogeneration Decreasing value proposition unused wood residues Biomass inventory for bio-power unused wood residues mill + harvest site

Forest Inventory in Manitoba Forest Inventory in Manitoba Total forest area 65,000,000 ha TPF area 15,300,000 ha Annual allowable cut 15,500 ha/yr TPF Volume 938,000,000 m 3 (national 26,159,000,000 m 3 ) Average non-stem wood density 55 ODT/ha (national 89 ODT/ha) Total of 836,000,000 ODT Forest residue Available: 20,000 BDT/a Potential: 140,000 BDT/a

Straw in Manitoba Land base total 65,000,000 ha farm 7,600,000 ha crop 4,700,000 ha others 3,000,000 ha Costs (fuel, harvest, store, transport) $35 to 60 $/dry ton

Types Wheat Cereal Straw in Manitoba Flax (high energy content) Canola (cannot bale) Straw high silica year to year variations Conservation tillage - 750 kg/ha Conventional tillage - 1500 kg/ha

Straw in Manitoba Energy use NRCan available 3,530,000 BDT/yr potential 6,500,000 BDT/yr Agriculture Canada Annual straw production: 1/3 conservation tillage and 2/3 conventional tillage Wheat Oats Barley Flax Total Cattle use Mega BDT/yr Alberta 3.06 1 2.82 0.006 6.89 5.41 Saskatchewan 4.8 1.07 1.97 0.15 7.99 2.12 Manitoba 3.09 0.78 1.07 0.15 5.1 1.34 Total 10.95 2.85 5.86 0.306 19.98 8.87 Lawrence Townley-Smith, Agriculture and Agri-Food Canada 2004

GIS System for Biomass Availability brown area will supply the required straw background colour is straw yield can select multiple sites to compare gaps in background are either noncropland or don t have enough straw to meet conservation requirements Source: L. Townley-Smith, Agriculture and Agri-Food Canada

Energy Crops in Manitoba Grow crops exclusively for energy Based on land availability and yield Large variation 4 to 35 ODT/ha/yr Costs (fuel, harvest, store, transport) $35 to 65 $/dry ton Resource land 1,702,000 ha assume 33% use available 5,050,000 BDT/a potential 15,300,000 BDT/a

Livestock Wastes in Manitoba Manures soil amendments direct application causes problems use for energy anaerobic digestion combustion/gasification Recoverable manure from Livestock in Manitoba Animals Average Mass Manure Daily Yearly Recoverable Mega Mega number kg/animal kg/animal Tonnes Tonnes % Tonnes/yr Diary Dairy 95,400 636 52 4,961 1.8 75% 1.4 Beef 1,300,000 568 34 44,200 16.1 25% 4.0 Poultry 7,085,385 1 0.06 425 0.2 85% 0.1 Swine 7,300,000 90 5 36,500 13.3 85% 11.3

BSE Disposal in Manitoba Need to kill prions high heat alkali hydrolysis plasma composting (storage) Biomass energy source 1.3 million cattle herd mortality 28,000 animals per year hard to get published data for disposal of BSE animals energy intensive

Urban Residues in Manitoba Organic wastes residential, commercial, industrial disposal issues Large quantities in urban areas MSW, sewage sludge, landfill gas, demolition residues Available in Manitoba 940,000 BDT/yr waste 358,000 BDT/yr MSW 20,600 BDT/yr Biosolids

NPK Marsh Filter Vegetation Class 2001 Area Covered Hectares (ha) % of Total Marsh Area Bulrush (Scirpus) 317.1 1.2 River Rushes 166.3 0.6 Cattail (Typha) 4533.8 17.6 Giant Reed (Phragmites) 522.6 2.0 Vegetation maps Netley- Libau Marsh 2001 Netley 1979 Area Harvest Moisture Biomass HHV Plant Available (Wet tonne) (Dry tonne) kj/kg Species (ha) min max (%) min max Dry Cattail 4987 8,528 118,267 17.1 7,070 98,043 18,229 Bulrush 3247 3,215 32,584 18.2 2,629 26,653 17,447 Reed Grass 650 1,112 1,170 12.8 969 1,020 17,285 Rushes, Sedges.. 922 954 6,638 12.4 836 5,819 15,838 Sum 9,806 13,808 158,659 11,505 131,535 Weighted average 16.7 18,024 From: Evaluation of a wetland-biopower concept for nutrient removal and value recovery from the Netley-Libeau marsh at Lake Winnipeg N. Cicek1, S. Lambert, H.D. Venema, K.R. Snelgrove, and E.L. Bibeau

Value Proposition Nutrient from Red River to Lake Winnipeg average 32,765 ton/yr of N; 4,905 ton/yr of P Biomass harvesting 3.1-4.2% of N; 3.8-4.7% of P Nutrient removal City of Winnipeg reduce N by 2,200 ton and P 260 ton in Red River estimated cost $181 million or $80,000 per ton of N Energy production Small Condensing Steam Small steam with cogeneration Organic Rankine Cycle Air Brayton cycle Entropic cycle Gasification 1 Heat recovery loss 8.0 8.0 7.8 12.3 5.3 11.0 (MW) Cycle loss 15.2 16.5 15.3 12.1 7.2 10.5 (MW) Power generated 3.03 1.75 3.13 1.83 3.68 4.71 (MWe) Cogeneration heat (MWth) 0.0 15.0 14.5 0.0 16.4 0.0 1 Assumes Producer gas has heat value of 5.5 MJ/m 3 and cooled down to room temperature

Peat in Manitoba 1.1 million km 2 Canada more than any country Manitoba 19% 1 billion tonnes proven 300+ billion tonnes (indicated or inferred) not used for energy horticultural only

Biomass Inventory How to relate? biomass availability BioPower potential Effects of conversion technology plant scale transportation feedstock analysis Starting point feedstock analysis modeling conversion CHP chart revenue CHP chart

BioPower and Feedstock Feed Analysis Mass Fraction Volume (dry) (wet) Fraction Carbon, C 50.0% 25.0% 29.50% Hydrogen, H 2 6.0% 3.0% 21.20% Oxygen, O 2 42.0% 21.0% 9.30% Nitrogen, N 2 2.0% 1.0% 0.60% Water, H 2 O 0.0% 50.0% 39.40% HHV = 20.5 MJ/BDkg fuel & 50% MC

Distributed BioPower CHP 50% moisture content Conversion Chart Bio-oil Gasification Syngas Air Brayton Best Large Steam Overall Power Efficiency 6.6% 7.8% 7.4% 29.2% Electricity (kwhr/bdtonne) 363 440 420 1659 Heat (kwhr/bdtonne) - - - - Overall Energy Efficiency 6.4% 7.8% 7.4% 29.2% Small Steam Small Steam CHP Organic Rankine Entropic Rankine Overall Power Efficiency 1 9.9% 5.7% 10.2% 12.0% Electricity (kwhr/bdtonne) 563 324 580 682 Heat (kwhr/bdtonne) - 2,936 2,713 3,066 Overall Energy Efficiency 9.9% 53.9% 54.5% 67.5% http://www.cec.org/files/pdf/economy/biomass-stageii-final.pdf

Distributed BioPower CHP Revenue Chart Electrical Power (USD) Natural gas (USD) $0.038 per kwhr $0.016 per kwhr USD Revenue (per BDtonne) Power Heat (60% use) Total Bio-Oil $13.9 n/a $13.9 Gasification $16.8 n/a $16.8 Air Brayton $16.0 n/a $16.0 1 Best Large Steam $63.3 n/a $63.3 Small Steam $21.5 n/a $21.5 Small Steam CHP $12.4 $29.0 $41.4 ORC $22.1 $26.8 $49.0 ERC $26.0 $30.3 $56.4 Note: Results are for 50% moisture content

ACKNOWLEDGEMENT Manitoba Hydro: Chair in Alternative Energy Natural Resources Canada Commission for Environmental Cooperation National Research Council Preto F., State-of-technology of electrical power generation from biomass, Advanced Combustion Technologies CANMET Energy technology Center, 2004 Wood S. and Layzell D., A Canadian biomass inventory: feedstocks for a bio-based economy, BIOCAP Canada Foundation, Kingston, June 27, 2003 (Many phone calls)

Modeling Approach Realistic small size systems limit cycle improvement opportunities cost effective for technology for small size limit external heat/power to system adapt component efficiencies to scale Model system as if building system today model actual conversion energy system ignore parasitic power for bio-oil & gasifier mass and energy balances Account for every step in conversion Exclude use of specialized materials

Bio-Oil Liquid: condense pyrolysis gases add heat; no oxygen organic vapour + pyrolysis gases + charcoal Advantages for distributed BioPower increases HHV lessens cost of energy transport produces value-added chemicals Disadvantages for distributed BioPower energy left in the char fuel: dry + sized sophisticated operators

Bio-Oil Slow pyrolysis Travelling Bed (fast pyrolysis) Rotating Cone (fast pyrolysis) Bubbling Bed (fast pyrolysis)

Bio-Oil JF Bioenergy ROI Dynamotive Ensyn Bio-oil (% by weight) 25% 60% 60% 75% 60% 80% Non-cond. gas (% by weight) 42% 15% 10% 20% 8% 17% Char (% by weight) 33% 25% 15% 25% 12% 28% Fuel feed moisture Not published <10% <10% <10% Fuel size Not published Not published 1 2 mm 1 2 mm Energy (kw/kg) 2.34 2.34 2.08 2.2 Water content bio-oil Not published 21% 23.40% <25% 10% moisture content + sizing to 2 mm drying heat: 3.72 5.1 MJ/kg h20 4.0 MJ/kg h20 and obtained from char (ROI) drying power: 917 1262 kwhr/bdtonne assumed 1050 kwhr/bdtonne; conservative; bound water sizing power: 150 200 kwhr/bdtonne assumed 170 kwhr/bdtonne

Bio-oil oil Overall Energy Balance Biomass Feed 50% moisture 21.5% energy loss Drying/Sizing to 10% / 2 mm 8% energy loss 18.5% 3% Power Pyrolysis 3% N 2 Sand 32% energy Char 60% energy Bio-oil Power5% 45.6% energy loss Engine/ Generator 6.4% Electricity Electricity: 363 kwhr/bdtonne Pyrolysis heat: non-condensable gas + some char (no NG) Pyrolysis power: 220 450 kwhr/bdtonne (335 or 5%) Use ICE: efficiency 28% (lower HHV fuel; larger engine; water in oil lowers LHV) Other parasitic power neglected (conservative) Limited use cogeneration product (char)

Gasifier Sub-stoichiometric combustion syngas: CO, CH 4, H 2, H 2 O contains particles, ash, tars Advantages for distributed BioPower engines and turbines (Brayton Cycle) less particulate emission Disadvantages for distributed BioPower flue gas cleaning cooling syngas, remove water vapor, filter tars fuel: dry + sized quality of gas fluctuates with feed

Gasifier Syngas Vol Dry vol Dry wgt fraction fraction kg/kg feed CO 0.1907 0.2994 0.461 CO 2 0.0365 0.0573 0.139 CH 4 0.0143 0.0224 0.02 H 2 O 0.363 0 0 H 2 0.1043 0.1638 0.018 N 2 0.2911 0.457 0.703 HHV (dry gas) 5.5 MJ/m 3 dry gas Assume require 25% MC and no sizing requirements (conservative) Ignore parasitic loads: dryer, gas cooler, gas cleaning, tar removal, fans (conservative) Heat to dry fuel comes from process (3.8 MJ/BDkg fuel ) 100% conversion of char to gas (conservative) HHV of syngas = 5.5 MJ/m 3 dry gas

Gasification Overall Energy Balance 15% energy loss 60% energy loss 17.25% energy loss Biomass Feed 50% moisture Drying to 25% Gasification 15% 40% energy Producer Gas Engine/ Generator 7.75% Electricity Electricity: 440 kwhr/bdtonne Low HHV of gas affects efficiency of engine Assume ICE operates at 75% of design efficiency 15% heat from producer gas dries fuel No heat loss across gasifier boundary Limited useable cogeneration heat

Small Steam Cycle (no CHP) 10 Superheater Economizer Boiler Attemporator Turbine 6 7 Ejector 8% steam Steam Rankine Cycle common approach 2% blowdown Feed Pump water boiled, superheated, expanded, condensed and compressed Advantages distributed BioPower well known technology commercially available equipment Disadvantages distributed BioPower costly in small power sizes large equipment and particulate removal from flue gas requires sophisticated and registered operator 9 3 8 4 Deaerator 2 1 Condenser makeup

Small Steam Overall Energy Balance 40.5% energy loss 49.6% energy loss Biomass Feed 50% moisture Heat Recovery Steam Cycle 9.9% Electricity Electricity: 563 kwhr/bdtonne Limit steam to 4.6 MPa and 400 o C (enable use of carbon steel) Use available turbines for that size: low efficiency (50%) No air pre-heater 4% parasitic load included in analysis Flue gas temperature limited to 1000 o C (NOx and material considerations) All major heat losses and parasitic loads accounted

ORC Advantages distributed BioPower smaller condenser and turbine as high turbine exhaust pressure higher conversion efficiency than small steam no chemical treatment or vacuum no government certified operators CHP dry air cooling can reject unused heat Disadvantage for distributed BioPower organic fluid ¼ of water enthalpy binary system, flammable thermal oil systems are expensive particulate removal from flue gas

ORC Overall Energy Balance 49.7% energy loss 40.1% energy loss Biomass Feed 50% moisture Heat Recovery Turboden Cycle 80 C liquid cogeneration 10.2% Electricity Electricity: 580 kwhr/bdtonne Heat: 2713 kwhr/bdtonne Flue gas temperature limited to 1000 o C (NOx and material considerations) Cool flue gas down to 310 o C CHP heat at 80 o C All major heat losses and parasitic loads accounted for

ERC Advantages for small BioPower pre-vapourized non-steam fluid small turbine and equipment no chemical treatment, de-aeration or vacuums no government certified operators ideal for CHP: 90 C to 115 C; return 60 C to 90 C dry air cooling can reject unused heat Disadvantages for small BioPower restricted to small power sizes (< 5 MW) system has not been demonstrated commercially special design of turbine particulate removal from flue gas

ERC Overall Energy Balance Biomass Feed 50% moisture 31.8% energy loss Heat Recovery 56.2% energy loss Entropic Cycle 90 C liquid cogeneration 12.0% Electricity Electricity: 682 kwhr/bdtonne Heat: 3066 kwhr/bdtonne Flue gas temperature limited to 1000 o C (NOx and material considerations) Cool flue gas down to 215 C CHP heat at 90 o C; return 60 o C All major heat losses and parasitic loads accounted for

Non-Steam Based Systems ORC & ERC 1000 C Input 310 C Heater 59.9% recovery 1000 C Input 215 C Heater 68.2% recovery 300 C Thermal Oil Heat Transfer 250 C TURBODEN srl synthetic oil ORC Conversion 17% 60 C 80 C Air heat dump Liquid Coolant 400 C Entropic Fluid Heat Transfer 170 C ENTROPIC power cycle Conversion 17.6% 60 C 90 C Air heat dump Liquid Coolant