Solid incineration

Combustion in an incinerator is the only practical way to deal with many waste streams.This is particularly true of solid and concentrated wastes and toxic wastes such as those containing halogenated hydrocarbons, pesticides, herbicides, etc. Many of the toxic substances encountered resist biological degradation and persist in the natural environment for a long period of time. Unless they are in dilute aqueous solution, the most effective treatment is usually incineration. 

Hearth incinerators. This type of incinerator is designed primarily to incinerate solid waste. Solids are moved through the combustion chamber mechanically using a rake. 

Of the 200 million tons of municipal solid waste collected in the United States in 1993 (1), 22% was recycled while 62% was placed in landfills and 16% incinerated (2). Plastics comprised 9.3% of these materials. The number of U.S. residential collection programs increased from 1,000 in 1988 to more than 7,000 involving more than 100 million people in 1993 (2). Approximate 1994 U.S. recycling rates are given in Table 1. 

D. Tillman, A. Rossi, and K. Vick, Incineration of Municipal and Iia rdous Solid Wastes, Academic Press, Inc., San Diego, Calif., 1989. 

Pollutant Emissions from Solid Waste Incinerators. 

R. S. Magee, Plastics in Municipal Solid Waste Incineration A Eiterature Study, Hazardous Substance Management Research Center, New Jersey Institute of Technology, Mar. 1989. 

Disposal The final func tional element in the sohd-waste-management system is disposal. Disposal is the ultimate fate of all solid wastes, whether they are wastes collected and transported direc tly to a landfQl site, semisolid wastes (sludge) from industrial treatment plants and air-pollution-control devices, incinerator residue, compost, or other substances from various solid-waste processing plants that are of no further use. 

Reduction of volume of solid wastes through burning (incineration)... 

Mass-fired incinerators, with and without heat recovery, for unprocessed wastes rotary kilns for hazardous/containerized and bulk solid/sludge waste... 

Incineration with Heat Recovery Heat contained in the gases produced from the incineration of solid wastes can be recovered as steam. The low-level heat remaining in the gases after heat recoveiy can also be used to preheat the combustion air, boiler makeup water, or solid-waste fuel. 

Concentration of WTE Incinerators The total number of municipal waste incinerator facihties as hsted in the Solid Waste Digest, vol. 4, no. 9 September 1994 (a publication of Chartwell Information Publishers of Alexandria, VA) is 62. See Table 25-69, which covers over 200 existing units. The wastes burned in these facilities totals 8.44 percent of total municipal wastes managed in landfills, incinerators, and transfer stations. This amounts to 88,470 tons per day combusted municipal waste. 

TABLE 25-69 Solid Waste Price Index, WTE Incinerator Intake TPD-Tip Fee, September 1994... 

Section 129 of the CAAA of 1990 applies to a range of solid waste incinerators including MWCs, medical waste incinerators (MWls)... 

EPA must issue New Source Performance Standards (NSPS) for any solid waste incineration unit not covered by another deadline lor issuance of such standards. 

EPA must issue NSPS for solid waste incineration units combusting industrial or commercial waste. (See May 15, 1992 action.)... 

Thermal energy, power generation, and incineration have several factors in common. All rely on combustion, which causes the release of air pollutants all exhaust their emissions at elevated temperatures and all produce large quantities of ash when they consume solid or residual fuels. The ratio of the energy used to control pollution to the gross energy produced can be a deciding factor in the selection of the control system. These processes have important differences which influence the selection of specific systems and devices for individual facilities. 

Wastes Anaerobic breakdown Admixture of effluents Open handling of effluents or wastes Atmospheric venting Solid wastes Uncontrolled incineration... 

Contaminated solid wastes are generally incinerated, and the flue gases are scrubbed. The emissions levels cited in Table 4 are those recommended by the World Bank Organization that should be achieved. 

The specific molecular mechanisms by which PCDDs and PCDFs are initially formed and become part of the PIC remain largely unknown and are theoretical. The theoretical basis for conjecture is derived primarily from direct observations in municipal solid waste incinerators. The emissions of... 

Venmri scrubbers have been applied to control PM emissions from utility, industrial, commercial, and institutional boilers fired with coal, oil, wood, and liquid waste. They have also been applied to control emission sources in the chemical, mineral products, wood, pulp and paper, rock products, and asphalt manufacrnring industries lead, aluminum, iron and steel, and gray iron production industries and to municipal solid waste incinerators. Typically, venturi scrubbers are applied where it is necessary to obtain high collection efficiencies for fine PM. Thus, they are applicable to controlling emission sources with high concentrations of submicron PM. 

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