Comparison of decomposition rate in supercritical water oxidation of various wastes

Abstract

Supercritical water oxidation was applied to the destruction of various wastes such as sewage sludge, alcohol distillery wastewater of molasses, .and shochu (rice spirit) distillery waste, and dog food as a garbage simulant. The reaction was carried out in a batch reactor with hydrogen peroxide as an oxidant in the temperature range of 673-823 K. Acetic acid and ammonia are found to be refractory intermediates in supercritical water oxidation of organic wastes. Total organic carbon (TOC) and ammonia concentration produced during the reaction were measured as a function of reaction time. The kinetic data were analyzed by a first order reaction model. Two generalized models including refractory intermediate such as acetic acid were developed and applied to the data analysis.