96/06783 TG/MS study of organic compounds evolved during the co-firing of coal and refuse derived fuels

Abstract

The Environmental Protection Agency reported that the total municipal solid waste (MSW) produced in the U.S. increased from 179 million tons in 1988 to 195 million tons in 1990. It is predicted that the country will produce about 216 million tons of garbage in the year 2000. Waste-to-energy conversion of MSW appears to be most attractive because of the energy recovered, economic value of the recycled materials, and the cost saving derived from reduced landfill usage. However, extra care needs to be taken in burning MSW or Refuse Derived Fuel (RDF) to optimize the operating conditions of a combustor so that the combustion takes place in an environmentally acceptable manner. For instance, polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) have been found in the precipitator fly ash and flue gas of a number of incinerator facilities in the United States and Europe. Though the amount of PCDDs and PCDFs is only in the parts-per-billion to parts-per-trillion range, these chlorinated organics exhibit very high toxicity (LD{sub 50} < 10 {mu}g/Kg) and 2,3,7,8-tetrachlorodibenzodioxin has been found to be acnegenic, carcinogenic, and teratogenic. This has slowed or even stopped the construction and operation of waste-to-energy plants. In previous work, the study of singlemore » materials has given us a good understanding of the characteristics and thermal behavior of these materials, their relative thermal stability and temperature relationships, their decomposition products and the evolution profiles of different gaseous products. The formation of molecular chlorine during combustion processes could be a key step for the formation of chlorinated organic compounds. The production of phenol and furan during the combustion of newspaper and cellulose could provide the important precursors for the formation of polychlorinated dibenzodioxin (PCDD) and polychlorinated dibenzofuran (PCDF).« less