Date of Award

Fall 2002

Document Type

Dissertation

Degree Name

Doctor of Philosophy in Environmental Science - (Ph.D.)

Department

Chemistry and Environmental Science

First Advisor

Robert Benedict Barat

Second Advisor

S. Mitra

Third Advisor

James M. Grow

Fourth Advisor

Barbara B. Kebbekus

Fifth Advisor

Larisa Krishtopa

Abstract

The two-stage combustor facility was used to investigate the process of chlorocarbon incineration and formation of products of incomplete combustion. For this purpose methylene chloride was used as a chlorine-containing compound. The propose of this research was to obtain a better understanding of the incineration process of chlorocarbons, such as methylene chloride, especially regarding its destruction efficiency and formation of products of incomplete combustion. For measuring near-real time very low concentrations of benzene and methylene chloride, on-line microtrap gas chromatography system was used.

The experimental system was validated using a known combustion reaction mechanism from literature. Modeling of combustion process has shown different pathways of benzene formation for first (perfectly stirred) and the second (plug flow) zones of the combustor with residence time 0.007 and 0.029 sec respectively. Destruction efficiency of methylene chloride was investigated under different equivalence ratio and inlet concentration. Influence of methylene chloride on formation of products of incomplete combustion such as methane, ethylene, ethane, and acetylene was investigated.

Combustion process was simulated using a reactor model and the reaction mechanism. Rate-of production analysis based on modeling results showed that there are different pathways for destruction of methylene chloride under fuel-lean and fuel-rich conditions. As shown by experimental results, destruction efficiency is lower at its lower concentrations. Simulations of experimental results on destruction of methylene chloride, methyl chloride, and benzene, has shown that significance of various radicals and destruction channels varies with combustion conditions and concentrations of organics, and that atoms and fragments of destroyed molecules play important role in further destruction of parent species. In order to describe the effect of additional radicals and fragments on the total rate of destruction additional rate function was derived and calculated for methylene chloride combustion cases.

Share

COinS