Ozonation of Volatile and Semi-Volatile Compounds for Groundwater Remediation

Abstract

Many of the U.S. EPA’s list of target volatile and semi-volatile priority pollutants can be removed by chemical oxidants such as ozone (O3) and hydrogen peroxide (H2O2). In the treatment reactor, the organic compounds are oxidized to various intermediates and end-products and/or volatilized to the gas phase during mixing or ozonation. The overall substrate removal process therefore, depends on the rate of volatilization as well as the chemical oxidation kinetics. This paper presents a methodology and develops a conceptual mathematical model for predicting the environmental fate of synthetic organics during treatment by chemical oxidation processes. It focuses on the use of ozone in bubble-type gas-liquid contactors since these units will exhibit significant removals by both oxidation and volatilization mechanisms. The general principals developed herein however, are applicable to other chemical oxidant systems if appropriate oxidation kinetic data are available. The proposed model and supporting analysis will facilitate identification and control of key process design variables to provide cost-effective treatment of wastestreams containing specific volatile and semi-volatile compounds.