Control of Hg0 re-emission from wet flue gas desulfurization slurry by sodium dithiocarbamate

Hg²⁺ can be reduced by reductant into Hg⁰ from wet flue gas desulfurization (WFGD) system, reducing co-benefit mercury removal efficiency of WFGD system. In this paper, the effect of the oxygen concentrations, the pH values and temperatures on Hg⁰ re-emission inhibition by sodium dithiocarbamate (DTCR), which was studied as one of the vital operating conditions, was to be studied. CaSO₃/CaSO₄ slurry was chosen as the experimental slurry which was closer to actual situation. The experimental results indicated that DTCR had an outstanding performance in Hg⁰ re-emission inhibition, and Hg⁰ re-emission inhibition efficiency by DTCR increased as the oxygen concentration and the pH values increased, and decreased as the experimental temperatures increased. The results above would be valuable for industrial applications of DTCR as a precipitant for inhibiting Hg⁰ re-emission in WFGD systems.