Effects of gaseous NH3 and SO2 on the concentration profiles of PCDD/F in flyash under post-combustion zone conditions

► Influence of NH3 and SO2 on 2378-PCDD/F in flyash and flue gases was investigated. ► NH3 decreased the concentration of PCDD and PCDF by 34-75% in the flyash. ► NH3 decreased the concentration of PCDD and PCDF by 21-40% from the flue gases. ► SO2 led to 99% PCDD and 93% PCDF reductions in the flyash. ► SO2 led to 89% PCDD and 76% PCDF reductions in the flue gases.