Kohei Urano*, Mika Kato*, Tomohiro Tasaki* and Chizuno Kimura*

* Yokohama National University

+Correspondence should be addressed to Kohei Urano:
(79-5 Tokiwadai, Hodogaya-ku, Yokohama 240 Japan)

Abstract

Sixteen runs of decomposition experiments of recovered chlorofluorocarbons (CFC-11, 12, 113) and hydrochlorofluorocarbon (HCFC-22) were carried out in 3 industrial waste incineration facilities with a rotary kiln, and the necessary conditions of the facilities and their operation for safe and reliable decomposition of CFCs/HCFC were clarified. At first, a quantitative characterization method for wastes and their incineration conditions was proposed, and the characteristics of the 3 facilities were clarified. Under conditions of an incineration gas temperature over 850*C[Celsius degeree], a gas residence time over 2seconds, an O2 concentration over 6vol%, and a molar ratio of hydrogen to halogen over 30, over 99.99% of the CFCs/HCFC decomposed and no volatile organochlorine compounds would be present. Moreover, PCDDs/PCDFs formation could be controlled by quenching of flue gas. A method to determine the optimum feed rate of CFCs/HCFC for each the facilities was proposed by concerning the produced concentrations of HCl and HF in the flue gas. The alkaline consumption and the costs for HCl and HF treatment were also estimated.

Key words: CFCs/HCFC, decomposition conditions, rotary kiln, industrial waste incineration facility, flue gas treatment