Incineration (energy recovery through complete oxidation) Mass Burn Refuse Derived Fuel Pyrolysis Gasification

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2 Incineration (energy recovery through complete oxidation) Mass Burn Refuse Derived Fuel Pyrolysis Gasification

3 WPC Plasma Gasification Reactor Cross Section Technology proven in 1989 at General Motors, Defiance Ohio Waste to Energy in 2001 at Hitachi Metals Eco-Valley, Utashinai, Japan WPC gasifier vessel 15 feet in diameter and over 50 feet tall Up to six (6) WPC plasma torches per gasifier Multiple feedstock capability Re-usable inert vitreous slag byproduct (road construction, insulation) Syngas clean up using off the shelf proven commercial equipment

4 Partial oxidation process using air, pure oxygen, oxygen enriched air, hydrogen, or steam Produces electricity, fules (methane, hydrogen, ethanol, synthetic diesel), and chemical products Temperature > 750 o C More flexible than incineration, more technologically complex than incineration or pyrolysis.

5 Product yields (dry feed basis) for pyrolysis of wood. Mode Conditions Liquid Char Gas Fast pyrolysis Slow Pyrolysis Gasification Moderate temperature, short residence time Low temperature, very long residence time High temperature, long residence time. 75% 12% 13% 30% 35% 35% 5% 10% 85% The Syngas is mainly H 2 and CO A.V.Bridgwater 5

6 Application: Power Generation Variety of Feedstocks Flexible Process Variety of Energy Products Optional Syngas Uses Air/Oxygen Steam MSW Coal Feed Handling Gasifier Gas Clean-up Syngas Boiler Steam Biomass Slag Aggregate Gas Turbine Electric Power

7 Thermoselect (

8 What is Plasma? Superheated gas where positive and negative charges are separated (ionized) Atoms of ionized gas have lost one or more electrons and have become positive charged Sun and lightning are natural plasma Man-made Plasma is created by passing electricity through a gas (air) causing a change in the state of the gas and a significant temperature increase often exceeding 10,000 o F. What is Gasification? Process that converts carbon-containing materials (MSW, biomass, coal, etc.) into a synthesis gas Syngas = carbon monoxide and hydrogen Syngas is a cleaner fuel than the original solid feedstock, resulting in cleaner emissions (reduced NOx, SO 2 )

9 Heating Technique using electrical arc Used for combustion, pyrolysis, gasification, metals processing Originally developed by SKF Steel in Sweden for reducing gas foriron manufacturing Temperatures (> 1400 o C) sufficient to slag ash Plasma power consumption kwh/ton

10 Plasma Gasification is not combustion Electricity Air Plasma Torch System Plasma (5,540 o ) Plasma Gasification converts solid fuel or organic waste into a clean gaseous fuel

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12 Refuse receipt/storage Refuse feeding Grate system Air supply Furnace Boiler

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14 Energy Loss (Radiation) Waste Flue Gas Mass Loss (unburned C in Ash)

15 Particulates Acid Gases NO x CO Organic Hazardous Air Pollutants Metal Hazardous Air Pollutants

16 Solid Condensable Causes Too low of a comb T (incomplete comb) Insufficient oxygen or overabundant EA (too high T) Insufficient mixing or residence time Too much turbulence, entrainment of particulates Control Cyclones - not effective for removal of small particulates Electrostatic precipitator Fabric Filters (baghouses)

17 From Cl, S, N, Fl in refuse (in plastics, textiles, rubber, yd waste, paper) Uncontrolled incineration % HCl with ph 2 Control Acid gas scrubber (SO 2, HCl, HFl) usually ahead of ESP or baghouse Wet scrubber Spray dryer Dry scrubber injectors

18 Source removal to avoid fuel NO x production T < 815 C to avoid thermal NO x selective catalytic reaction via injection of ammonia

19 Remove certain waste components Good Combustion Practices Emission Control Devices

20 Electrostatic Precipitator Baghouses Acid Gas Scrubbers Wet scrubber Dry scrubber Chemicals added in slurry to neutralize acids Activated Carbon Selective Non-catalytic Reduction

21 Bottom Ash recovered from combustion chamber Heat Recovery Ash collected in the heat recovery system (boiler, economizer, superheater) Fly Ash Particulate matter removed prior to sorbents Air Pollution Control Residues usually combined with fly ash Combined Ash most US facilities combine all ashes

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23 Construction fill Road construction Landfill daily cover Cement block production Treatment of acid mine drainage

24 Net Electricity to Grid Plasma Advantage % Plasma Arc Gasification Conventional Gasification - Fixed/Fluidized Bed Technologies Pyrolysis & Gasification - Thermoselect Technology Pyrolysis - Mitsui R21 Technology Incineration - Mass Burn Technology % 40% 50% Reference: EFW Technology Overview, The Regional Municipality of Halton, Submitted by Genivar, URS, Ramboll, Jacques Whitford & Deloitte, Ontario, Canada, May 30,

25 Emissions can be made cleaner than natural gas emissions from domestic household gas stoves. 25