Tomoyuki Imai*, Yasuhiko Fujii*, Toshiki Matsui* and Tasuku Nakai*

* Toda Kogyo Corp.

+ Correspondence should be addressed to Tomoyuki Imai:
(1-4 Meijishinkai, Otake-city, Hiroshima 739-0652 Japan)

Abstract

Combustion experiments with the injection of an iron oxide catalyst using an intermittently-operated and mechanical batch-type incinerator for municipal solid waste were carried out. As a result, it was observed that the oxide injection had a notable suppressive effect on dioxin formation and the removal function of hydrogen chloride was highly promoted by the combination of calcium hydroxide and the catalyst. The dioxins in combustion flue gas decreased to 20-30% of the quantity of the formation without the iron oxide catalyst, and the iron oxide catalyst decreased the total quantity of dioxins emitted from the incinerator, including fly ash. Because the formation of iron chlorides has a strong influence on dioxin formation, the possibility of the formation of iron chlorides from the iron oxide catalyst was studied thermodynamically.

Key words: intermittently-operated incinerator, iron oxide catalyst, dioxins, memory phenomenon