Transcript Achieving “Zero Waste” with Plasma Arc Technology Louis J. Circeo, Ph.D.

Achieving “Zero Waste”
with
Plasma Arc Technology
Louis J. Circeo, Ph.D.
Director, Plasma Applications Research Program
Robert C. Martin, Jr.
Michael E. Smith
Electro-Optics, Environment and Materials Laboratory
Achieving “Zero Waste”
Plasma arc technology offers a unique opportunity
to achieve the “zero waste” goal by providing the
capability to eliminate the need for land disposal
of many hazardous wastes and to recover energy
from municipal solid wastes and other organic
wastes while producing salable byproducts and
eliminating requirements for landfilling of ash or
other residual materials.
What is PLASMA?
• “Fourth State” of matter
• Ionized gas at high
temperature capable of
conducting electrical
current
• Lightning is an example
from nature
Non-transferred arc plasma torch
In a plasma arc torch, the plasma gas serves
as a resistive heating element to convert
electricity into heat. Because it is a gas and
cannot melt, temperatures in excess of 7000°C
can be produced.
Plasma torch in operation
Characteristics of Plasma Arc
Technology
• Plasma acts as a resistive heating element that cannot
melt and fail
• Produces temperatures of 4,000°C to over 7,000°C
• Torch power levels from 100kW to 200 MW produce
high energy densities (up to 100 MW/m3)
• Torch operates with most gases – not a combustion
process
• Elimination of requirement for combustion air
– Reduces gas volume requiring treatment
– Reduces potential for formation of complex organics (i.e.,
dioxins and furans)
Plasma arc technology is ideally
suited for waste treatment
• Hazardous & toxic compounds broken down to
elemental constituents by high temperatures
• Organic materials
– Pyrolyzed or volatilized
– May be converted to fuel gases
– Amenable to conventional off-gas treatment
• Residual materials (radionuclides, heavy metals, etc.)
immobilized in a rock-like vitrified mass which is
highly resistant to leaching
Plasma arc technology remediation
experience
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Heavy metals
Radioactive wastes
Industrial sludges
Municipal solid waste
Electric arc furnace dust
Liquid/solid organic
wastes
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PCB’s
Asbestos
Chemical wastes
Medical wastes
Plastics
Used tires
Waste Processing Applications
of
Plasma Arc Technology
Waste
Destruction
Energy/Material
Recovery
Waste Destruction Applications
• Melting and vitrification of inorganic materials
• Pyrolysis of organic materials
– Molten metal or glass bath provides heat transfer
– Heat causes breakdown of complex materials into elemental
components
– Rapid quenching prevents complex compound formation
(dioxins and furans)
– Water gas shift reaction to remove carbon
• C + H2O → H2 + CO
– Gaseous products are fuel and simple acid gases
– Vitreous residue is resistant to leaching – suitable for aggregate
U.S. asbestos stockpile disposal
French Asbestos-Containing
Materials (ACM) disposal system
Incinerator ash disposal
Navy shipboard system
Navy Shipboard System – cont’d
Recent Commercial Applications
• Mixed waste treatment facility-Richland, WA
– Allied Technology Group (ATG)
• Medical waste vitrification facility-Honolulu, HI
– Asia Pacific Environmental Technologies (APET)
• Incinerator ash vitrification facilities – Europe and
Japan
– Europlasma
– IHI Inc./Westinghouse Plasma
Recent DoD Plasma Furnace
Applications
• Plasma Arc Shipboard Waste Destruction System
(PAWDS)
• U.S. Navy Warships (NSWCCD)
• Plasma Arc Hazardous Waste Treatment System
(PAHWTS)
• U.S. Naval Base, Norfolk, VA (Office of Naval Research,
Environmentally Sound Ships Program)
• Plasma Ordnance Demilitarization System
(PODS)
• Naval Surface Warfare Center, Crane, IN (Defense
Ammunition Center)
Recent DoD Plasma Furnace
Applications – cont’d
• Plasma Waste Treatment System (Pyrotechnics and
Energetics)
• Hawthorne Army Ammunition Plant, NV (Armament Research and
Development Engineering Center)
• Plasma Energy Pyrolysis System (PEPS) Demonstration
Facility (Medical Waste and Blast Media), Lorton, VA
• U.S. Army Construction Engineering Research Laboratories (CERL)
• Mobile PEPS Demonstration System, U. S. Army CERL
Mobile Plasma Energy Pyrolysis
System (PEPS)
GaTech Plasma Waste Processing &
Demonstration System
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Developed by USACERL
Congressional funding
Cost ~$6 Million
Capacity 10 tons/day
Complete system
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Feed & Tapping
Furnace
Emissions control
Wastewater treatment
1MW mobile generator
Georgia Tech Plasma Waste Processing and
Demonstration System
Plasma Processing for Energy and
Materials Recovery
• Research on waste destruction noted that
pyrolysis produced useful fuel gases and inert
residuals from organic wastes including MSW
• Relatively high plasma energy requirements
(~600 kWh/ton) and capital cost of complex
molten bath reactors limited economic feasibility
of pyrolysis processes
• Use of gasification technology has made plasma a
more economically attractive alternative
Plasma Pyrolysis of MSW
Gas Heating Value Output
= 4.30
Electricity Input
Steam
Negligible
Gas Heat Energy
1.05 MBtu
MSW
PLASMA
1 Ton – 9.39 Mbtu
33% Moisture
GASIFIER
Electricity
0.56 MWHr – 1.90 MBtu
Product Gas
30,300 SCF
Heating Value =
8.16 MBTU
Based on data from Resorption Canada, Ltd. 1995
(Summarized and converted to English units)
Hitachi Metals
Plasma MSW System – Japan
Coke
and
Limestone
Plasma Torch
Metal
Slag
Excess Heat
Utilization & Power
Generation
Hitachi Metals
200 TPD MSW Plant - Utashinai Japan
Hitachi Metals
Utashinai, Japan Plant
Commercial 200 ton/day plasma processing system
• Designed for Municipal Solid Waste (MSW) and
Automobile Shredder Residue (ASR)
– Represents MSW from approximately 30,000 US households
• Plant has two plasma reactors
– Four 300 kW torches (Westinghouse Plasma Corp.) per reactor
– Each reactor will process ~4 tons/hr
• Generates 7.9 MW of electricity (4.3 MW to grid)
– Could supply 4,000 US households with electricity (up to 15%
of households supplying waste to the system)
• Fully operational in April 2003
Vitrified MSW residue
Leachability of Vitrified MSW
Residue (TCLP)
Metal
Permissible
concentration (mg/l)
Measured
Concentration (mg/l)
Arsenic
5.0
<0.1
Barium
100.0
<0.5
Cadmium
1.0
<0.02
Chromium
5.0
<0.2
Lead
5.0
<0.2
Mercury
0.2
<0.01
Selenium
1.0
<0.1
Silver
5.0
<0.5
MSW Solid Byproduct Uses
Molten Stream
Processing
(Product)
Salable Product Uses
Air Cooling
Coarse Aggregate (roads,
concrete, asphalt)
(Gravel)
(Sand)
Fine Aggregate (concrete,
asphalt, concrete products)
Water Cooling
Recyclable metals
Water Cooling
(Metal Nodules)
Air Blown
(“Rock Wool”)
Insulation, sound proofing,
agriculture
PLASMA PROCESSING OF MSW AT
COAL-FIRED POWER PLANTS
Concept
• Collocate MSW plasma processing plants (in modules of 1,000 TPD) with
existing operational coal-fired power plants.
• The amount of coal supplied to a plant will be reduced, proportionate to the
thermal output of the MSW plant.
• The hot gaseous emissions from the plasma plant afterburner system will be fed
directly into the coal plant combustion chamber to supplement the combusted
coal gases.
• The combined plasma and coal gaseous emissions would produce steam and
power equal to the normal coal plant generating capacity.
• MSW would replace large volumes of coal for power generation in a very
efficient, cost-effective and environmentally cleaner operation.
PLASMA PROCESSING OF MSW AT
COAL-FIRED POWER PLANTS
Reduced Capital Costs of MSW Plant(1)
• Use existing power plant facilities
– Steam generation system
– Off gas treatment system
– Electrical generating system
• Use existing transportation network
• Build on power plant land, if feasible
(1)
Geoplasma, LLC estimated costs
PLASMA PROCESSING OF MSW AT
COAL-FIRED POWER PLANTS
Summary
By 2020, if all MSW was processed by plasma at coal-fired power
plants (1 million TPD), MSW could:
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Supply about 5% of U.S. electricity needs
Replace about 140 million TPY of coal
Eliminate about 15 million TPY of coal ash going to landfills
Provide significantly cleaner coal plant air emissions
Support the goals of the Clear Skies Act
YEAR 2020
SELECTED RENEWABLE ENERGY SOURCES
Source
Plasma Processed MSW(1)
Geothermal(2)
Landfill Gas(2)
Solar(2)
Wind(2)
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(1) Assumes 1 million TPD
(2) Extrapolated from 1999 statistics
Quads
(1015 BTU)
0.90
0.47
0.12
0.09
0.04
Capital Costs: Incineration vs Plasma
Gasification Facilities
Cost ($millions)
300
200
Incineration Only
Incineration WTE
Plasma Stand Alone WTE
Plasma Integrated WTE
100
(Note: Plasma Costs are Geoplasma
LLC Estimates)
0
0
1000
2000
3000
Capacity (tons/day)
Potential DoD Applications
• Processing of hazardous wastes
– Major installations
– Industrial activities (depots, Air Force Plants)
• “Bare Base” and “Zero Footprint” Operations
– Process solid and sanitary wastes
– Eliminate landfill or shipping of residuals
– Recovery of energy as steam or hot water
Barriers to implementation of Plasma
Arc Technology
• Successful commercial applications in US
• Regulatory acceptance and permitting
• Public acceptance
For More Information:
• Contact:
– Lou Circeo: [email protected]
(404-894-2070)
– Bob Martin: [email protected]
(404-894-8446)
– Mike Smith: [email protected]
– (404-894-0281)
Georgia Tech Research Institute
EOEML/SHETD/ETB
430 Tenth Street NW
Atlanta, GA 30332-0837