Hidekichi Yoshino* and Kohei Urano**

* Kanagawa Environmental Research Center, Division of Environmental Engineering
** Yokohama National University, Lavoratory of Safety and Environmental Engineering

+ Correspondence should be addressed to Hidekichi Yoshino:
(842 Nakaharashimojyuku, Hiratsuka-shi, Kanagawa, 254-0072 Japan)

Abstract

The authers reported about mutagenic activities and mutagenic compounds in exhaust gas from municipal waste incinerators in steady operation term. In this study, mutagenic activities and concentrations of PAHs at starting and stopping terms of the municipal waste incinerators were investigated in comparison with these in the steady operation term. Mutagenic activities of the exhaust gas were higher in fluidized bed furnaces where CO concentration were widely varied. However, they were not higher at starting and stopping term than steady operation term. The mutagenic activities at starting term were higher than steady operation term when large amount of solid wastes was fed in furnace for quick heating. On the other hand, the mutagenic activities at stopping term were not higher than steady operation term in all the incinerators. In order to decrease the mutagenic activities, the incineration must be started by gradual feeding wastes or preheating with oil, be fed wastes constantly in steady term, and be supplied full volume air in stopping term as in steady operation term. Mutagenic activities increased with the concentration of fluoranthene and benzo (b) fluoranthene, but these mutagenic levels were almost same and their contribution ratios for the mutagenic activities of the exhaust gas were low in every term.

Key words: incineration of MSW, starting term, stopping term, exhaust gas, mutagenic activities