Evaluation of Thermal Processes for CCA Wood Disposal in Existing Facilities
Florida Center for Solid & Hazardous Waste Management
Anadi Misra1, Chang-Yu Wu1, Timothy Townsend1, Helena Solo-Gabriel2
1 University of Florida, Department of Environmental Engineering Sciences2Miami University, Department of Civil Engineering
October 22, 2004
2004 Fall TAG Meeting
Construction & Demolition Landfill
6 %CCA Wood
~ 60% are Burned for
Energy Recovery
Incineration of CCA Wood
• Heavy Metal Emissions from combustion– Volatilization and entrainment
• Leaching of Heavy Metals from Ash into Groundwater– A hidden problem often ignored
Specific GoalsTo evaluate thermal processes for CCA
wood disposal in wood fired capable facilities in the state of Florida
• How many facilities are available for thermal process of CCA treated wood in the state of Florida?
• What is the capacity of each viable facility? • What technologies are available for effective
control of emission and leaching of the metals?
MethodologyTask 1: Inventory of Existing Wood-Fired
Capable Facilities • Facilities that use wood as their fuel • Facilities can possibly be converted to burn
wood (e.g. cement kilns, coal fired power plants, waste-to-energy plants)
Cement plant
Type Max. Heat input rate
Types of fuels used Air pollution control devices
Cement Kiln(7)
290-437MMBtu/hr
Coal (bituminous usually), whole tires, propane, natural gas,petroleum coke, propane, No. 2 fuel oil, residual fuel oil, No. 6 fueloil
Baghouses, Scrubbers
Coal Fired(14)
179.3-7172MMBtu/hr
Coal (bituminous , pulverized, latex coated, mixed with petroleum coke), natural gas, Nos.1,2 & 6 fuel oil, carbonaceous fuel, Briquette Mixture, refuse derived fuel (RDF)
Cold side & Hot side ESP, flue gas desulphurization (FGD) unit, wet caustic scrubber , Selective Non Catalytic Reduction system (SNCR)
, spray dryer absorber, and fabric filter baghouse
Inventory of Combustion Facilities in Florida
Type Max. Heat input rate
Types of fuels used Air pollution control devices
WoodFired(31)
2.0 -805 MMBtu/hr
carbonaceous fuel (bagasse, wood chips, rice hulls), natural gas, bark and primary clarified wood fibers, dry wood waste, combination of waste wood and paper( with some lesser amounts of peanut hulls, lumber, oily rags, oil soaked peat moss) MSW, Coal, No. 2 & 6 fuels, oil soaked paper towels, biomass, sugar mill waste, tires, landfill gas.
fly ash arrestor, wet caustic scrubber , SNCR, Multicyclone, ESP, venturi scrubber, multiple tube dry collectors, Joy type Impingement Scrubber, spray dryer absorber, fabric filter
WTE(14)
53.6- 458 MMBtu/hr
MSW fabric filter baghouse, spray dry absorbers, activated carbon injection system, SCNR , dry scrubber, mercury abatement systems, electrostatic precipitator (ESP)
Inventory of Combustion Facilities in Florida (cont.)
Task 2: Survey of Available Pollution Control Technologies
• Mechanical collection and chemical transformation technologies from the literature and equipment vendors.
Task 3: Screening of Potential Materials for Preventing Arsenic Leaching from Incineration Product
• Potential mineral sorbents evaluated in a bench-scale incinerator
• Ash will be analyzed according to TCLP for leaching properties and XRD to identify the crystalline composition
Arsenic retained in ash from CCA wood/sorbent combustion
600 750 900Temperature (oC)
Iida et al., J. Env. Eng., 130(2), 184-192, 2004.
TCLP leaching level of arsenic in ash from CCA wood/sorbent combustion
XRD pattern of As2O3 with Ca(OH)2 at 1000 oC
Mahuli et al., Env. Sci. Technol., 31, 3226-3231, 1997
Fraction of Arsenic Leachable by TCLP for Various Mineral Sorbents
Venkatesh et al., Haz. Was. Haz. Mat., 13(1), 73-94, 1996.
Impact if Specific Objectives Are Met
• Regulatory Agencies: establish pertinent strategy for better management of CCA wood disposal
• Environmental professionals: make an informed decision on the best option for managing their CCA wood waste through better understanding of the cost-effectiveness and applicability of the alternative technology.
Possible Follow-Up
• Test how these materials perform in mixed fuels - field test: Energy & Environmental Research Center at University of North Dakota
• Cost analysis for retrofit
conversion and environmental process simulator (CEPS)
Pitts et al., JAWMA, 49, 1190-1200, 1999.