Alternative Approach to Current EU BAT Recommendation for Coal-Fired Power Plant Flue Gas Desulfurization Wastewater Treatment

Abstract

Fossil fuel combustion is a serious environmental problem. Significant quantities of flue gasses and wastewater, requiring further treatment, are produced. This article compares three wet flue gas desulfurization (FGD) wastewater treatment methods: coagulation with precipitation using iron(III) ions—recommended by the European Union as the best available technique (BAT)—and two alternative advanced oxidation processes (Fe2+/H2O2 and Fe0/H2O2). Both oxidation processes that were used met the technical FGD wastewater treatment requirements of the BAT. The best treatment effects, expressed as pollutants’ removal, were obtained for the Fe2+/H2O2 process for 150/300 mg/L reagent doses. It allows effective removal of boron up to 212 mg/L and heavy metals up to below the detection limit <0.010 mg/L for Pb and <0.005 mg/L for Cu. Therefore, the Fe2+/H2O2 process could be an option for FGD wastewater treatment as an alternative to the BAT recommended iron(III)-based coagulation with precipitation. Additionally, an analysis of variance was applied to check the significance of the two independent variables and their interactions. Statistical analysis confirmed high efficiency and applicability of treatment process.