Incineration pollution control

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. 

Add-on Control Device an air pollution control device such as carbon absorber or incinerator that reduces the pollution in an exhaust gas. The control device usually does not affect the process being controlled and thus is "add-on" technology, as opposed to a scheme to control pollution though altering the basic... 

Air Pollution Control Device Meehanism or equipment that eleans emissions generated by a source (e.g., an incinerator, industrial smokestack or an automobile exhaust system) by removing pollutants that would otherwise be released to the atmosphere. 

The incineration process may be viewed as consisting of four parts (1) preparation of the feed materials for placement in the incinerator (pretreatment), (2) incineration or combustion of the material in a combustion chamber, (3) cleaning of the resultant air stream by air pollution control devices (APCDs) which are suitable for the application at hand, and (4) disposal of the residues from the application of the process (including ash, and air pollution control system residues). 

Residuals Produced Fluidized bed incineration produces no separate ash as such, but solids are carried over in the gas stream and will require removal. Residuals from the air pollution control devices may require additional treatment prior to disposal. 

The characteristics of the downstream pollution discharge must be monitored (see Fig. 13.18). It is essential that the operation and maintenance of the pollution control equipment be included in a quality audit procedure, assisting in determining the operation efficiency of the equipment and the formation of unwanted and possibly toxic compounds in the pollution control steps. Unsuitable operation of an incinerator may result in partial oxidation and formation of unwanted combustion products or excessive formation of MO. 

Many compounds can cause problems in pollutant-control equipment. Particulate matter, liquids, or solids in the waste stream can plug the adsorber beds, heat-recovery beds in regenerative thermal incinerator systems and biofilters. Conventional filtration systems are used to remove particulate matter before or after the process. 

As many emissions involve chlorinated compounds, corrosion is a major problem in many control methods. The corrosion of columns and surface condensers can be prevented or reduced by the correct material selection. However, corrosion remains a constant threat to the interior of incinerators. Additional pollution control equipment such as scrubbers may also be required to remove acidic compounds from treated gases before discharging into the atmosphere. 

Both these methods relate to the required removal efficiencies of the pollution control equipment. All abatement methods achieve high removal efficiencies when used in the correct applications (Fig. 13.19). The highest efficiency (with limitations) is in most cases achieved with incineration. When removal efficiencies of 99% or greater are required, incineration is usually recommended. ... 

Adsorption is the most widely used solvent-recovery technique and is also used for odor control. The latter application is necessary to meet statutory air pollution control requirements. Depending on the application, adsorption can be used alone or with other techniques such as incineration. " ... 

Public concerns about air quality led to the passage of the Clean Air Act in 1970 to amendments to that act in 1977 and 1990. The 1990 amendments contained seven separate titles covering different regula-toiy programs and include requirements to install more advanced pollution control equipment and make other changes in industrial operations to reduce emissions of air pollutants. The 1990 amendments address sulfur dioxide emissions and acid rain deposition, nitrous oxide emissions, ground-level ozone, carbon monoxide emissions, particulate emissions, tail pipe emissions, evaporative emissions, reformulated gasoline, clean-fueled vehicles and fleets, hazardous air pollutants, solid waste incineration, and accidental chemical releases. 

Health-related institutions again show the future trend in a microcosm. Suitable incineration facilities may determine the ability of such institutions to function effectively in an urban environment. When adequate processes for solid waste and air pollution control by incineration are developed, the use of combustible, one-way trip disposables for all incoming materials can be expected to accelerate. This will result in a decrease in the need for a direct fuel supply. 

According to EPA (1974), pesticides such as endosulfan should be destroyed at high temperature in an approved incinerator with a hydrochloric acid scrubber, if available. Any sludges or solid residues generated from this process are to be disposed of in a manner approved by all applicable federal, state, and local pollution control requirements. EPA strongly recommends that if incineration of excess pesticides is not possible, organic pesticides should be buried in a designated landfill site. 

Incineration (needs control of gaseous pollutants and solids, see e.g. Table 13.13) Dumping at sea... 

Waste treatment prior to disposal may introduce phase changes which result in quite different pollution control considerations. For example, the gases generated by incineration of a solid waste can be scrubbed with liquid in order to meet an acceptable discharge criterion hence, in addition to ash for disposal, a liquid effluent stream is produced and requires treatment. Other waste treatment processes may result in the liberation of flammable or toxic gaseous emissions as exemplified in Table 16.5. 

OppeltET. 1987. Incineration of hazardous waste. A critical review. J Air Pollut Control Assoc 37 558-586. 

Another critical part of the incinerator design is the pollution control system.11 Pollution control systems directly influence the levels and kinds of pollutants that are released and that can potentially reach the public. Most modern hazardous waste incinerators are designed with extensive air pollution removal systems. For example, a common pollution control system might include a system that cools or quenches gases produced by burning waste, followed by a system that reduces acid gas emissions, and ultimately followed by a particulate removal system such as fabric filters (bag-houses), electrostatic precipitators, venturi scrubbers, and others.10... 

HC1 is an acidic gas that forms when chlorinated organic compounds in hazardous wastes are burned. An incinerator burning hazardous waste cannot emit more than 1.8 kg of HCl/h or more than 1% of the total HC1 in the stack gas prior to entering any pollution control equipment, whichever is larger. 

Boomer, B.A. and Trenholm, A.R., Common deficiencies in RCRA Part B incinerator applications, Journal of the Air Pollution Control Association, 37 (3), 275-277, 1987. 

Carotti AA, Kaiser ER. 1972. Concentrations of twenty gaseous chemical species in the flue gas of a municipal incinerator. J Air Pollut Control Assoc 22 224-253. 

The water hyacinth Eichhornia crassipes originates from Brazil, and although it represents one of the most troublesome and invasive of water weeds, it is also one of the best phytoremediants of polluted water. The biomass becomes saturated with pollutants, which can then be removed from the water by harvest of the biomass and its composting, a process which achieves a substantial reduction in the mass requiring further processing (e.g., incineration under controlled conditions). The species is highly susceptible to frost, but in frost-free environments, its introduction is risky as it can readily become uncontrollable. 

Incineration of hazardous wastes in an acceptable manner requires a rather sophisticated facility in terms of the actual incinerator, its associated control systems, and the pollution control devices. Existing industrial production facilities as well as dedicated hazardous waste incinerators have been investigated for potential application. 

Incineration has been used extensively in hospitals for disposal of hospital wastes containing infectious and/or hazardous substances. Most hospital incinerators (over 80%), however, are outdated or poorly designed. Modem incineration technology, however, is available for complete destmction of organic hazardous and infectious wastes. In addition, adequate air pollution control facilities, such as scmbbers, secondary combustion chambers, stacks, and so on, are needed to prevent acid gas, dioxin, and metals from being discharged from the incinerators. 

Oberacker, D.A. Incineration options for disposal of waste pesticides. In Pesticide Waste Disposal Technology Bridges, J.S., Dempsey, C.R., Eds. Noyes Data Corporation Park Ridge, NJ, 1988. Eckenfelder, W.W., Jr. Industrial Water Pollution Control, 2nd ed. McGraw-Hill New York, 1989. McNally, R. Tougher rules challenge future for injection wells. Petrol. Eng. Int. 1987, July, 28-30. Zimpro, Inc. Report on Wet Air Oxidation for Pesticide Chemical Manufacturing Wastes, prepared for G. M. Jett, USEPA Rothchild Wisconsin, 1980. 

The Alka/Sorb air pollution control system is designed to remove dioxin, furans, toxic metals, acid gases, and particulates from industrial and medical incinerator off-gas. The Alka/Sorb system consists of a dry treatment/wet scrubbing process during which incinerator off-gas is cooled, contacted with an alkaline powder, injected with a sorbent, filtered by a baghouse and then wet-scrubbed for final removal of trace acid gases. Two central parts of the Alka/Sorb system include a wet-acid scrubber and a patented sorbent called Diox-Blok, which prevents the formation of dioxins and furans in air emissions. 

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