Influence of Chlorine Forms and Dechlorination on Dioxins Formation/Suppression in the Combustion Processes

Abstract

Chlorine sources, forms and chlorine concentration of combustion materials are considered to be the most important factors influencing the formation of dioxins/furans (Dioxins) in the combustion processes. Therefore, one of the effective methods to suppress the formation of Dioxins is expected to dechlorinate from combustion materials at high temperatures. In the present work, effects of chlorine sources, forms and chloride concentration on the formation of Dioxins and effect of the dechlorination on the suppression of Dioxins formation in the combustion process have been investigated in the combustion furnace of a laboratory scale at 1073 K.The concentration of Dioxins formation is nearly proportional to the chloride content of combustion materials under the conditions of the same chlorine sources and forms, and besides, its concentration is significantly influenced by chlorine sources, i.e. organochlorine compound or inorganic chloride. Furthermore, even in the case of inorganic chloride, Dioxins of high concentration are formed under the existence of the active chlorine with high reactivity such as chlorine ion in the hydrate, made from salt and flour. On the other hand, Dioxins are hardly formed by the dechlorination from combustion gas and fly carbonaceous matters with CaO chips put in the combustion furnace.