Incinerator destruction processes

In the feed pretreatment section oil and water are removed from the recovered or converted CCI2F2. The reactor type will be a multi-tubular fixed bed reactor because of the exothermic reaction (standard heat of reaction -150 kJ/mol). After the reactor the acids are selectively removed and collected as products of the reaction. In the light removal section the CFCs are condensed and the excess hydrogen is separated and recycled. The product CH2F2 is separated from the waste such as other CFCs produced and unconverted CCI2F2. The waste will be catalytically converted or incinerated. A preliminary process design has shown that such a CFC-destruction process would be both technically and economically feasible. 

Johanson, J. G. Yosim, S. J. Kellogg, L. G. Sudar, S. "Elimination of Hazardous Wastes by the Molten Salt Destruction Process," Proc. 8th Annu. Res. Symp. Incineration and Treatment of Hazardous Waste, EPA-600/9-83-003,... 

There are four vapor phase treatment processes (a) thermal destruction, (b) catalytic incinerahon, (c) ozone destruction with ultraviolet radiation, and (d) granular carbon adsorption (GAC). Processes a-c are not widely utilized due to cost and/or effectiveness of treatment. Thermal destruction is an effective process, but the operating cost is very high due to energy requirements. Catalytic incineration, shown in Fig. 7, has lower energy requirements compared to the thermal destruction process, but it is not effective in eliminating low levels of chlorinated organic compounds. Ozone destruction with an ultraviolet radiation process has limited performance data available as a result, the performance of this process must be examined in a pilot study for the particular VOC in question in order to determine operational parameters. The most commonly used vapor phase treatment process for VOC is carbon adsorption. 

Note that the risk associated with retrieving the munitions from the bunkers and moving them to the destruction facilities is approximately the same regardless of the destruction process employed, incineration, neutralization, or other. 

Theimal processing can be accomplished by incineration of the debris at high temperature (>1000°F) or by thermal desorption/decomposition at lower temperatures (<320° to 900°F). High-temperature incineration systems process the waste at high temperature and then pass the combustion off-gas through an afterburner and final off-gas cleaning devices (e.g., filters, carbon absorbers, and/or scrubbers) to ensure as complete as possible destruction and control of contaminants. 

Incineration of dioxin wastes is the most versatile destruction process of those presently available. The mobile incinerator treated a combination of soil, sludge, and solvents... 

The process has a number of advantages over destruction processes, particularly incineration ... 

Based on the type of thermal destruction process selected, there are several different commercial designs and configurations of the reactor that have been utilized for a particular application. Some of the most commonly used technologies include rotary kilns, starved air incinerators, fluidized beds, mass-bum incinerators, electrically heated reactors, microwave reactors, plasma, and other high-temperature thermal destruction systems. Recent advances include gasification and very high temperature steam reforming. 

Project policy prohibited the importation of any additional waste for destruction and excluded the use of commercial fecilities for the disposal of final waste products from the destruction processes. Prior to starting destruction operations, a comprehensive public consultation program (see below) was undertaken to address concerns regarding potential safety, health risks and environmental impacts associated with the project. To address public concerns regarding possible post-project uses of the incinerator, DND issued a public statement that the incinerator would be removed upon completion of operations. 

Lewisite Destruction Process Rather than incinerate lewisite and its byproducts as originally proposed, the modified plan called for lewisite to be chemically neutralized with the collected arsenate salts and neutralizing solution inunediately stabilized in concrete without any incineration. This approach removed concerns regarding the potential for arsenic emissions during incineration. 

Communities near chemical weapon storage depots in the United States are understandably worried about accidental spills or releases. M55 rockets containing large quantities of sarin (SB) are of particular concern. Some of this ordnance has been known to leak, and there is a very small risk of explosion from propellants. Extra safety precautions have been instituted to ensure safe incineration and to limit the amounts of effluent released into the environment. Despite the risks inherent in the destruction process, the dangers in allowing the weapons to rust and leak have been determined to be greater than carrying out the disposal. 

Many industrial wastes, including hazardous wastes, are burned as hazardous waste fuel for energy recovery in industrial furnaces and boilers and in incinerators for nonhazardous wastes, such as sewage sludge incinerators. This process is called coincineration, and more combustible wastes are utilized by it than are burned solely for the purpose of waste destruction. In addition to heat recovery from combustible wastes, it is a major advantage to use an existing on-site facility for waste disposal rather than a separate hazardous waste incinerator. 

Thermal processes are typically used for highly toxic waste or highly concentrated organic wastes. If the waste contains PCB, dioxins, or other toxic substances, incineration should be chosen in order to assure destruction. If the wastes contain greater than 1000 parts per million of halogens (chlorinated materials), it would probably be desirable to select incineration of these wastes, after consideration of other options. In any case, a material may be incinerated or used as a fuel if the heat content is greater than 8500 BTUs per pound or, if between 2500 and 8500, it may be incinerated with auxiliary fuel. The waste components of concern are halogens, alkali metals and heavy metals. 

USATHAMA) completed a trial burn of explosive, contaminated soil in a rotary kiln (Noland, 1984). Soil contaminated from red and pink water lagoons was successfully burned. A transportable rotary kiln yrstem was set up. The technology by Therm-All, Inc., had been used in industry for destruction of solid wastes. The normal screw feed system was not used, due to fear of a soil explosion during the extruded plug feed process. Therefore, the soil was placed in combustible buckets and individually fed by a ram into the incinerator. The feed rate was 300 to 400 Ib/hr and the operational temperature was 1200° to 1600°F in the kiln and 1600° to 2000°F in the secondary chamber. 

Combustion is the rapid exothermic oxidation of combustible elements in fuel. Incineration is complete combustion. Classical pyrolysis is the destructive distillation, reduction, or thermal cracking and condensation of organic matter under heat and/or pressure in the absence of oxygen. Partial pyrolysis, or starved-air combustion, is incomplete combustion and occurs when insufficient oxygen is provided to satisfy the combustion requirements. The basic elements of each process are shown on Figure 27. Combustion of wastewater solids, a two-step process, involves drying followed by burning. 

Thermal and catalytic incinerators, condensers, and adsorbers are the most common methods of abatement used, due to their ability to deal with a wide variety of emissions of organic compounds. The selection between destruction and recovery equipment is normally based on the feasibility of recovery, which relates directly to the cost and the concentration of organic compounds in the gas stream. The selection of a suitable technology depends on environmental and economical aspects, energy demand, and ease of installation as well as considerations of operating and maintenance. 7 he selection criteria may vary with companies or with individual process units however, the fundamental approach is the same. 

The advantages of thermal incineration are that it is simple in concept, has a wide application, and results in almost complete destruction of pollutants with no liquid or solid residue. Thermal incineration provides an opportunity for heat recovery and has low maintenance requirements and low capital cost. Thermal incineration units for small or moderate exhaust streams are generally compact and light. Such units can be installed on a roof when the plant area is limited. = The main disadvantage is the auxiliary fuel cost, which is partly offset with an efficient heat-recovery system. The formation of nitric oxides during the combustion processes must be reduced by control of excess air temperature, fuel supply, and combustion air distribution at the burner inlet, The formation of thermal NO increases dramatically above 980 Table 13.10)... 

The routine monitoring of every hazardous constituent of the effluent gases of operating incinerators is not now possible. EPA has established procedures to characterize incinerator performance in terms of the destruction of selected components of the anticipated waste stream. These compounds, labeled principal organic hazardous components (POHCs), are currently ranked on the basis of their difficulty of incineration and their concentration in the anticipated waste stream. The destraction efficiency is expressed in terms of elimination of the test species, with greater than 99.99 percent removal typically judged acceptable provided that toxic by-products are not generated in the process. 

Infrared thermal destruction technology is a thermal processing system that uses electrically powered silicon carbide rods to heat organic wastes to combustible temperatures. Any remaining combustibles are incinerated in an afterburner. One configuration made by ECOVA Corporation consists of four components65 ... 

Thermal processes like pyrolysis use heat to increase the volatility (separation) to burn, decompose, or detonate (destruction) or to melt (immobilization) contaminants in soil. Separation technologies include thermal desorption and hot gas decontamination. Destruction technologies include incineration, open bum/open detonation, and pyrolysis. Vitrification is used to immobilize inorganic compounds and to destroy some organic materials. In contrast, pyrolysis transforms... 

Electrochemical destruction of organics can be an economically viable alternative to incineration, carbon beds, bioremediation, deep well disposal and other methods as destruction to very low acceptable levels is possible [227a], Electrochemical techniques are in fact superior to incineration or deep well disposal as it is a final solution and not a transfer of a toxic material from one environment to another, e.g. to the groundwater or the atmosphere [285], Common destruction pathways include both direct and indirect electrolysis. Many electrochemical degradation pathways remain unclear and may be a mixture of direct and indirect processes depending on the pollutant and its intermediates [84,285a]. 

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