Biomass Gasification: Emerging Technologies for Converting Biomass to Pipeline-Quality SNG presented to Wisconsin Public Utility Institute Natural Gas Symposium July 22, 2008 by Vann Bush Gas Technology Institute

> Not-for-profit R&D –50+ yr history in gasification – Extensive commercialization activities – Staff of 240 (70% scientists and engineers, 38 PhD’s, 15 PE licenses) > Addressing Key Issues for the Natural Gas Industry –Contract Research –Program Management –Technical Services –Education and Training Over 1,000 patents Nearly 500 products commercialized 2

3 DELIVERYEND USESUPPLY Efforts Aligned with the Industry Value Chain Secure, stable, competitive domestic energy supply Unconventional Gas Resources Gasification for Alternative Supply Strategic Focus Address strategic concerns of domestic gas T&D infrastructure Safety Pipeline Integrity Cost Reduction Efficiency Improve affordability & applicability of gas Energy efficiency Environmental performance Interchangeability Needs C a r b o n M a n a g e m e n t

Multiple Routes to Renewable Energy From Biomass Resource Agriculture Forestry Animal Waste Muncipal Waste Conversion Thermochemical gasification pyrolysis Biochemical anaerobic digestion alcohol fermentation activated waste treatment Use Biopower electricity heat CHP Biofuels methanol ethanol / DME F-T liquids pyrolysis liquids hydrogen SNG Bioproducts many …… Gas Cleanup / Upgrading Particles Tar, organics Sulfur NOx CO 2 4

Biomass-Derived Methane Products 5 * Sustainable N atural G as * Substitute Natural Gas

Renewable SNG Advantages > Biomass-to-power in PC boiler –Lowest efficiency (~30%); limited co-firing range; boiler and site modifications can be costly > Biomass-to-power with gas turbine –Lower efficiency (40-50%) without waste heat integration; real-time power pricing may reduce value of non-peak power > Cellulosic fermentation –Modest efficiency (50%); limited distribution system; high water demand; technology still in R&D > BtL via Fischer-Tropsch –Modest efficiency (35-45%) without significant heat/steam integration; higher capital; product needs further refining > SNG –Higher efficiency (65-70%); increased efficiency with waste heat integration; pipeline infrastructure-ready, storable product; commercial technology available 6

Gasification – A Means to a Secure, Renewable Gas Supply Gasification Excellent Environmental Performance Carbon Management Opportunity Syngas Pipeline Quality Gas / Chemical Feedstock Liquefaction Power Plant Fuel Power Plant Pipeline / Chemical Plant Transportation Fuels 7

HYGAS - SNG STEAM-IRON - H 2 U-GAS - Syngas RENUGAS - Syngas Mild-GAS - Coal-refining GTI Energy Development Center

9 What is Gasification? SORBENT/ BED MATERIAL FUEL: Coal, Biomass, Wastes GASIFIER AIR or Oxygen STEAM ASH AND SPENT SORBENT Products (syngas): CO (carbon monoxide) H 2 (hydrogen) (CO/H 2 ratio can be adjusted) By-products: H 2 S (hydrogen sulfide) CO 2 (carbon dioxide) Solids (minerals from fuel) Gas Cleanup Before Product Use Process Conditions: Pressure = 1 to 60 atm or more Temperature =1600 – 2600 °F

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100 ton per day Bioenergy Demo Plant in Hawaii using bagasse 80 ton per day Gasification Pilot Plant in Tampere, Finland using biomass & coal GTI Biomass Gasifier Projects 165 ton per day CHP Plant in Skive, Denmark using wood 40 ton per day Pilot Plant at GTI using biomass & coal 11

Simplified SNG Process 12 SNG S, Cl, dust, etc. CO 2, H 2 O, H 2 Biomass Coal

13 Syngas for Substitute Natural Gas > Upstream units (gasifier, cleaning) similar to IGCC (power) > Several Gasifier options – (feed flexibility, scale, gas quality differences) > Downstream technologies for SNG production available from multiple providers > One plant operational on coal since 1984 – several other projects announced > No biomass – to – SNG commercial plants

Commercial Methanation Systems Produce SNG at Pipeline Specs Example Product Specs Mole % CH CO H2H2 COnil N 2 +Ar2 - 3 HHV (Btu/scf) Wobbe # Methanation Process by Haldor-Topsøe

Gasification Technology Direct, partial oxidation gasification (fixed bed, multi-stage, fluidized bed, entrained flow) Indirect gasification (including steam reforming) Hydrogasification Catalytic gasification Supercritical water gasification 15

Some of the Biomass Gasifier Technology Providers * 16 Indirect (Battelle/FERCO/ SilvaGas/Taylor, Repotec, TUV) (Battelle/FERCO/ SilvaGas/Taylor, Repotec, TUV) Multi-Stage Choren Carbo-V, BCT Fluidized Bed GTI, Andritz/Carbona, EPI, Emery Energy * Fixed bed gasifiers not included.

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18 GTI independent process simulation for a different set of technologies also yields >65% net efficiency.

Project Initiative in Göteborg, Sweden 19

1 MW Pilot Plant for Slurry Methanation Reactor in Austria 20

R&D of New Technical Aproaches is Active in All Process Areas Examples include: Gasification – Supercritical water gasification – Catalytic gasification – Hydrogasification Syngas Conditioning – Tar catalysts – Multi-contaminant processes – Hot-gas cleanup Methanation Systems – Slurry reactors – Contaminant-resistant catalysts 21

22 Summary > Biomass gasification and syngas methanation to SNG is a highly efficient process to produce a renewable gas product at natural gas pipeline quality. > SNG can be produced from domestic biomass resources with current technologies. Several initiatives have been announced for European applications. > Advanced technologies are being developed for all steps in the process, promising improved performance and economics.