Suppression of 1,4-dioxane by environmentally friendly high reactive slaked lime

Abstract

Compared to JIS special slaked lime, highly reacted slaked lime uses a smaller amount, which has the advantage of reducing flue gas treatment costs and the amount of fly ash. On the other hand, it has been reported that 1,4-dioxane is generated from organic components contained in highly reacted slaked lime during the waste gas treatment process, and there have been cases where dioxane has actually been detected in elution tests of solidified fly ash from waste incineration facilities. We have developed a low environmental impact type of highly reactive slaked lime that suppresses the elution of organic components, and have attempted to suppress dioxane formation by using this type of lime. It was confirmed that the use of low environmental impact type highly reactive slaked lime can suppress the generation of 1,4-dioxane, which was observed with conventional highly reactive slaked lime, while maintaining the same acid gas removal performance. The generation of 1,4-dioxane is related to the organic components eluted from the highly reactive slaked lime, and the COD value of the highly reactive slaked lime can be used as an indicator of the amount of 1,4-dioxane contained.