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Show research is clearly needed. [6J Clearly one cannot make this assump-tion for POHCs injected at different points in an incinerator (e . g ., rotary kiln and an afterburner). Thus, the problem becomes one of developing a set of standard temperatures, residence times, and reaction atmospheres that can be used to effectively predict incinerability ranking for a vari~ty of systems under a variety of operating conditions. We have previously proposed the temperature for 99% destruction at 2.0 seconds gas-phase residence time, [T99 (2)(OC)], as one method of ranking the thermal stability of POHCs. Other residence times or temperatures may be used to develop this ranking. However, laboratory data indicates that although absolute POHC DEs are dependent upon time and tempera-ture, the relative DEs are relatively insensitive to these parameters. [4,7] On the other hand, reaction atmosphere has been shown to be a major variable in determining relative stability. [6] The general concept of reaction atmosphere may be broken down into three parameters; molecular composition, elemental composition, and fuel/air stoichiometry. Under the pseudo-equilibrium hypothesis, it is assumed that the concentrations of small, highly reactive radicals (e.g., OH,H,O,Cl) achieve equilibrium even though the over-all system is not at equilibrium. Since bimolecular reactions involving these species along with unimolecular pathways govern the ~ rate of POHC decomposition, only the elemental composition of the waste feed and fuel/air stoichiometry will affect the DE of the waste. Equilibrium calculations for various waste feed elemental compositions at a given ~xygen concentration and waste feed con-centration indicate that the concentrations of reactive radicals does not vary appreciably for typical waste compositions. In contrast, |