POLYSTYRENE VS POLYPROPYLENE
Introduction
The
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The public sees plastic as a major contributor to the solid waste problem. Two-thirds believe that the environmental risks of using plastics outweigh benefits; recycling programs are favored in these cases. Four-fifths believe recycling can reduce the amount of solid waste. Rowatt reports that in fact each person discards about 3.6 pounds of material per day, with 80 percent going to landfills, 10 percent recycled, and 10 percent incinerated. Packaging materials make up around 30 percent of the waste and plastic packaging makes up about 13 percent of the packaging. Therefore the waste contains approximately 3.9 wt percent plastic packaging; "plastics make up 7 percent of waste by weight and 18 percent by volume." The real concern is whether the plastics are being effectively handled. A hierarchical program to solve the waste problem includes source reduction, recycling, landfill, and incineration (7:56). Environmental concern includes safety precautions regarding plastic incineration. Research includes the investigation of soot release with potential dangers, during combustion of both polystyrene and polypropylene. Styrene, when heated to 200 degrees is converted into the polymer, polystyrene. Polystyrene is a clear plastic with excellent insulating properties; it is used for the manufacturing of plastics, synthetic rubber, resins, and as an insulator. Potential symptoms of overexposure
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n increased use of polymeric materials for household items and building materials, there is an increased need for safe disposal of their wastes. Polymeric materials are not biodegradable and their recycling is limited by technical and economic problems; incineration is a major method of disposal. This method, although efficient, presents a problem of air pollutants generated during combustion. Soot is a problem for many polymeric materials including polystyrene and polyvinylchloride (1).
Soot is a hazardous pollutant because soot particles are the proper size to be ingested deep into the lungs, and because they carry polynuclear aromatic hydrocarbons known to be carcinogenic. Advanced particle removal devices are employed to control soot emission, however, the size of soot particles results in low removal efficiencies. Additionally, soot deposition causes blockage and erosion in incinerator units and increased emissivity and higher radiative heat transfer from abundant soot formation can result in overheating which damages the incinerator. It is therefore important to control soot formation during combustion during the incineration of polymeric materials (1).
The authors found that soot yield can be reduced by controll
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Some common words found in the essay are:
Prado Lahaye, Pasternak Zinn, Polypropylene Styrene, Chung Tsang, POLYPROPYLENE Introduction, Thoma Hutzinger, Increased O2, Zinn Studies, Ca Na, Lewis Sax's, polystyrene polypropylene, soot formation, flame front, polymeric materials, combustion polystyrene, soot yield, flame retardant, soot yield reduced, carbon atom, atom chain, soot release, flame front concentrations, carbon atom chain, soot formation distribution, near flame front,
Approximate Word count = 1512
Approximate Pages = 6 (250 words per page)
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