Study on the Removal of Dioxins in Exhaust Gas of Incinerator by Artificial Zeolite

Abstract

In this study, the effects of space velocity (SV) and gas temperature on the removal rate of Dioxins (polychlorinated dibenzo-p-dioxins, polychlorinated dibenzofurans=PCDD/DF) in exhaust gas of incinerator by fly ash-derived artificial zeolite were investigated. The highest removal rate calculated by TEQ value (98.7%) of vapor PCDD/DF in exhaust gas of small size incinerator was found at 150°C and 10000h^-1 as SV value. Removal rate decreased with the increase of gas temperature and/or with the increase of SV value, and also relatively low removal rate of vapor PCDD/DF was found in low chlorinated PCDD/DF-congeners and -isomers. These results suggested that the adsorption mechanism of PCDD/DF by artificial zeolite was mainly due to physical adsorption. However, rapid increase of vapor PCDD/DF concentration was found at 300°C. It was considered due to new synthesis of PCDD/DF, so called de-novo synthesis. Furthermore, considering these observations, the removal method of PCDD/DF by artificial zeolite will be effective in small size incinerator.