Study on Behavior of Perfluorocarboxylic Acids in Wastewater Treatment Plants in Consideration of the Formation Potential from Their Precursors

Abstract

 Main objective of this study was to examine the behavior of perfluorocarboxylic acids (PFCAs) during treatment processes at a WWTP by (a) analysis of PFCAs at each treatment process (b) study on the examination methods of formation potential of PFCAs from their precursors in wastewater samples (c) calculation of mass flow of PFCs through treatment processes in consideration of the formation potential from their precursors. As a result; a) PFOA and PFNA concentrations were increased through treatment processes and more than 200 % of the mass in the effluent were returned to the aeration tank with return sludge. b) Oxidation process with potassium persulfate under alkaline condition resulted in evaluating 317 ng/L of PFOA formation potential (4.5 times higher than original concentration) and 929 ng/L of PFNA formation potential (5.0 times higher than the original) in return sludge. c) PFCAs were not balanced during the biological treatment and secondary settling processes while those resulted in being better balanced by considering the mass of formention potentials of PFCAs.