Extraction of Pharmaceuticals from Activated Sludge and Behavior During Wastewater Treatment Process

The extraction method for 27 Pharmaceuticals and Personal Care Products (PPCPs) from the activated sludge was compared when accelerated solvent extractor (ASE) was applied. As an appropriate solvent, water was found most effective. When, the developed method was applied to field survey at Wastewater Treatment Plant (WWTP), levofloxacin was found to be most sorbed to sludge as high as 930ng/g-dw for sludge content. Solid-water coefficient (Kd) value ranged between 1.6 (crotamiton) and 4.8 (mefenamic acid) for both activated sludge and primary sludge. Mass balances in activated sludge process were estimated, which suggested that there are 3 kinds of the compounds whose behavior differed. Levofloxacin tended to be sorbed on/in primary sludge and returned sludge. Theophylline was hardly sorbed on/in sludge but was removed by more than 90% probably due to its biodegradation. Crotamiton was also hardly sorbed on/in sludge and 80% of the load at primary effluent passed through the activated sludge.