Abstract
Chlorinated volatile organic compounds (CVOCs) such as chloroform (CF), carbontetrachloride (CTC), tri- and tetrachloroethylene (TCE and PCE) are pollutants commonly found in ground water and soil. Their oxidation in a novel, bubble column photochemical reactor combining the mass transfer of pollutant from the gas phase followed by a free-OH radical reaction in a liquid phase (UV/H2O2 system) is described mathematically and in terms of economic feasibility. It was shown that the reaction rates in liquid phase followed the pseudo-first order kinetics and the process could be therefore examined for electrical energy efficiency by the figure of merit Electrical Energy per Order (EE/O). The EE/O values were shown to depend on the initial concentration of pollutant and hydrogen peroxide, as well as the reactor radius. In all cases, the value of EE/O is decreasing with increasing reactor radius, as does the apparent rate constants of pollutant degradation. It was shown that the levels of PCE and TCE in the order of 20 mg/L could be treated economically. However, the treatment of compounds with low affinity to OH radicals was shown to be economically unfavorable even for ppb level concentrations.
