Characteristics of dioxin emissions from a Waelz plant with acid and basic kiln mode

► Characteristics of PCDD/F emission from Waelz process with acid/basic operating modes are compared. ► Ca(OH)2 added in basic mode effectively reacted with and HCl(g) and reduced PCDD/F formation. ► Operating the Waelz process in basic more greatly reduced total PCDD/F emissions. ► Total PCDD/F emission is reduced from 640 to 269 ng I-TEQ/kg EAF-dust treated.