Mechanisms for the Formation and Destruction of Chlorinated Organic Products of Incomplete Combustion

Abstract

Abstract This paper is concerned with the chemical kinetic basis for the formation and destruction of by-products during the incineration of hazardous wastes. Special attention is focussed on the chlorinated organics since certain classes of such compounds are frequently detected in incinerator effluents. Our approach is to concentrate on single step elementary processes and to use the existing chemical kinetic data base for hydrocarbon combustion as a starting point. We begin by listing available thermodynamic and kinetic data bearing on the processes of importance during incineration. This information is then used to examine the possible reaction pathways. Although definitive results can only be obtained from detailed modeling, our analysis demonstrates the importance of the nature of the reaction mixture. An important variable is the ratio of hydrogen to chlorine and when this ratio is low, chlorination of unburnt hydrocarbons may be an important source of undesirable side products. It is expected that formation of products of incomplete combustion will be greatest under pyrolylic conditions. This illustrates the importance of proper mixing. Extensions to other systems are considered.