Speciation Change of Flocs During Electrocoagulation for Wet Flue Gas Desulfurization Wastewater

Wastewater produced from wet flue gas desulfurization (WFGD) process contains large amounts of suspended solids (SS), heavy metals and salinity. Compared to traditional chemical coagulation, electrocoagulation (EC) technology is a novel technology to remove these pollutants with lower O&M costs and simplified facilities. In order to achieve better EC effects, the speciation change of flocs generated from two kinds of sacrificed electrodes (e.g., Al and Fe) is investigated in various operation parameters. The results show that iron anode performed better compared to aluminium anode. At 20V of voltage and 6cm of electrode gap, the percentage of polymeric species of iron flocs can reach more than 50%. The significant domination of polymeric species under the optimal conditions during electrocoagution is responsible for the turbidity removal.