Proper atomization is a crucial step in any liquid-fueled, combustion-driven process. Thermal waste treatment (i.e. incineration) processes are particularly sensitive to operating conditions such as atomization quality, due to the complex and often flame-inhibiting chemical kinetics involved and the need for high levels of operating efficiency and fault tolerance. Researchers have suggested that, for incineration-resistant chlorinated hydrocarbon (CHC) wastes, the composition of the waste stream can be manipulated to influence droplet vaporization and enhance burning. Experiments employing single suspended droplets and linear droplet arrays have supported this theory. However, these results have not been extended to realistic three dimensional droplet dispersions, where dense spray conditions could foster droplet interactions. The thesis of this dissertation is that droplet interactions may alter the multicomponent droplet vaporization observed in previous experiments of reduced dimension.; The experimental methodology involved introducing sprays of pure 1,1,1-trichloroethane (TCA) and mixtures of TCA and various alkanes into the post-flame region of a vertically oriented combustion-driven flow reactor, and extractively sampling the exhaust gases for FTIR spectroscopic analysis. A novel airblast atomizer design was developed to allow independent variation of spray mean droplet size and spray mean density. Species concentrations during the thermal destruction of TCA have been obtained for lean and near-stoichiometric post-flame conditions; several different mean (Sauter mean diameter) and two alkane blending agents, over droplet sizes; several different mean spray densities, a temperature range of 800--1200 K. Selected observations from the results include (1) the thermal destruction of TCA exhibits a dependence on ambient equivalence ratio, contrary to previous assertions of unimolecular decomposition, (2) both spray mean droplet size and spray density can impact pure TCA destruction and byproduct formation, (3) droplet number density within the spray so influences the vaporization of bicomponent mixtures as to virtually eliminate the enhancement resulting from addition of alkanes, (4) denser multicomponent sprays exhibit the most desirable vaporization and destruction characteristics, which is counterintuitive given the understanding of conditions within dense sprays, and (5) multicomponent sprays consisting of mixtures previously shown to be beneficial to droplet vaporization resulted in undesirable perturbations and trends for byproduct species concentrations.
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