Variations in heavy metals and turbidity in wastewater from wet flue gas desulfurization by electrocoagulation

Wastewater containing various contaminants, including total suspended solids (TSS), heavy metals, and salts, is produced from the wet flue gas desulfurization (WFGD) process. Electrocoagulation (EC) was compared to traditional chemical coagulation methods and applied as a novel technology to treat WFGD wastewater in this study. Based on three different combinations of electrodes (Al-Al, Fe-Al and Fe-Fe), the dependence of the heavy metal (Zn and Ni) contents and the turbidity on the electrolyzer voltage and electrode gap was investigated. The results show that optimal removal efficiencies of 82.56% and 52.37% for Zn and Ni, respectively, can be achieved at a voltage of 20 V and an electrode gap of 2 cm, while the turbidity sharply decreases from 488 NTU to 8.3 NTU. The application of Fe as an anode can enhance pollutant removal and electrochemical stability in WFGD wastewater.