Effects of Chlorine Sources and Forms on Formation of Dioxins/Furans in the Combustion Process

Hirotoshi Kawabata*, Tateo Usui*, Katsukiyo Marukawa**, Sigeta Hara*
Hideki Ono-Nakazato* and Toshihiro Tanaka*
* Department of Materials Science and Processing, Graduate School of
Engineering, Osaka University, Japan
** Cooperative Research Center for Advanced Science and
Technology, Osaka University, Japan
+ Correspondence should be addressed to Hirotoshi Kawabata:
(2-1, Yamadaoka, Suita-city, 565-0871 Japan)

Abstract
Chlorine sources and forms are considered to be the most important factors in the formation of Dioxins/Furans (Dioxins) due to the fact that Dioxins are organochlorine compounds. In the present work, effects of chlorine sources and forms on the formation of Dioxins in the combustion process have been investigated, mainly through combustion experiments and also through thermodynamic evaluations on the formation of Dioxins in the combustion furnace of a laboratory scale at 800*C[Celsius degeree].
Dioxins are formed even at the combustion temperature of 800*C[Celsius degeree] by the existence of four constituents, i.e. C, H, O and Cl. The formation concentration of Dioxins is nearly proportional to the chloride concentration of combustion materials under the conditions of the same chlorine sources and forms, and is significantly influenced by chlorine sources, i.e. organochlorine compound or inorganic chloride. Even in the case of inorganic chloride, Dioxins of high concentration are shown from combustion experiments to be formed by the existence of an active chlorine such as the hydrate, made from salt and flour.

Key words: chlorine source, chlorine form, dioxins/furans, hydrate, formation model of dioxins