Polyvinyl chloride, incineration

Polyvinyl chloride (PVC) is a common plastic that can produce dioxins and furans when burned. PVC is often present in municipal waste in large amounts, and is believed to contribute to the dioxins and furans from incinerators. Many sources of combustion produce dioxins and furans. Incinerators, both municipal and industrial, are significant sources dioxins and furans have been found in incinerator ash and in gases and tiny particles escaping through smokestacks. Power plants, smelters, steel mills, oil and wood stoves, and furnaces all emit dioxins and furans. 

Another area of environmental concern is the products themselves. Petroleum refining in the last 10 years has been driven by requirements for the composition of gasoline and diesel fuel that are continuously changed by environmental demands. Such considerations will have even stronger impact in the future. There are similar problems in the chemical process industries. The search for an environmentally acceptable substitute for Freon is a prominent present example. Another problem is polyvinyl chloride (PVC), which causes difficulties in incinerators. The question is, should we continue to produce PVC or should we find a substitute that is easier to dispose of Can we modify polymers in such a way that they cause fewer problems of pollution than they cause now These are major challenges for the profession, in both academia and industry. 

The incineration of DPE suits (which are made of a mixture of polyvinyl chloride, chlorinated polyethylene, resins, plasticizers, and metal stabilizers) is subject to the same dioxin emission limits at industrial incineration facilities as they are at chemical agent disposal facilities. Thus the waste feed load and incineration bum conditions for any of these chlorinated materials into incineration units may be regulated to meet air emission control requirements. These emission control limits and resulting incineration performance requirements are spelled out in the RCRA and Clean Air Act Title 5 permits for each site. 

The Danish minister of environment in 1988 announced that within a few years the manufacture and use of polyvinyl chloride (PVC) products had to be reduced as much as technically and economically possible due to their environmental impacts of production, use, and disposal. This preventive environmental policy was mainly based on the emission of hydrogen chloride and dioxins from waste incineration. A study of the technical, economic, and environmental consequences of a substitution was initiated by the National Agency of Environmental Protection. The goal was to collect background data for the upcoming negotiations between the environmental authorities and PVC-industry and manufacturers of PVC products in Denmark. The environmental assessment focused on PVC and 11 alternative materials, such as polyethylene (PE), polypropylene (PP), polyethylene terephtalate (PET), polystyrene (PS), polyurethane (PUR), synthetic rubbers (EPDM, CR and SBR), paper, impregnated wood, and aluminum. ... 

For some excipients, the global acceptability of some packaging materials varies from country to country. This can often stem from environmental concerns and the negative impact from the need to dispose of packaging waste. For example, polyvinyl chloride (PVC) is used widely to manufacture bottles and blisters for pharmaceutical products, but there is a growing concern about its safe use and disposal in some countries (Hansen 1999). Incineration is the preferred method of disposal for PVC, with the downside that it emits toxic gases. Materials that are readily biodegradable, or that can be recycled, are preferred. This is not always possible with some types of synthetic materials. 

TCDD was detected in stack emissions, slag, or wash water, while some PCDDs were detected only in ppt amounts in stack emission (Brenner etal. 1986). The levels of PCDDs and PCDFs in the incinerator flue gases were found to be slightly high when the amount of wet leaves in the municipal solid waste was higher (Marklund et al. 1986). The increase in polyvinyl chloride (PVC) content in the waste feed did not produce emissions with detectable concentrations of dioxins and dibenzofurans (Carrol 1988 Giugliano et al. 

The presence of chlorinated organic matter in a fuel will result in the formation of objectionable substances like HCl, halogenated acids, and other organochlorine compounds in the incinerator exit gases and particles (Eiceman et al., 1979 Mowrer and Nordin, 1987). During the combustion of chlorine-containing organic materials such as polyvinyl chloride and polyvinylidene chloride (36 and 37, respectively), new... 

For each use, the disposal pathways must then be determined before a complete exposure profile can be constructed. Incineration usually results in complete destruction. The effectiveness of landfilling as a means of chemical disposal is a function of a chemical s persistance, its relative solubility, and its degree of soil adsorption. Other possible disposal methods include ocean dumping, use of sealed containers, disposal in specially designed chemical waste depositories, or merely leaving it in place as is the case with building supplies like polyvinyl chloride (PVC) pipe. 

Most plastics bum cleanly, producing emissions of carbon dioxide, nitrogen oxides, and water vapor, but some produce unwanted by-products such as polyvinyl chloride (PVC). However, PVC and such other by-products can be safely burned at high temperatures of 980 to 1,650°C (1,800-3,000°F), using controlled oxygen input, sufficient cycle (residence) time, typically i to 2 minutes, and appropriate auxiliary equipment like scrubbers and solid salts. However, most U.S. incinerators operate below 87°C (1,600°F) and use only limited auxiliary equipment. For example, incinerated PVC generates undesirable chlorine (and bleached paper generates much more chlorine). Exhaust scrubber systems must be used to remove this chlorine. 

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