| Abstrakt: |
Conventional sewage treatment techniques have shown low removal efficiency for emerging contaminants (ECs). Hence, more efficient treatment systems need to be investigated. The current study suggests that an Integrated Fixed-Film Activated Sludge Process (IFAS) could be one such alternative. The degradation of eight ECs in municipal sewage has been studied during the transition of a pilot IFAS plant to a steady state and compared with the removal of the eight ECs in a conventional sequencing batch reactor (SBR)–based sewage treatment plant at a steady state. In the six weeks before attaining a steady state, the outlet total biochemical oxygen demand, total chemical oxygen demand, and total suspended solids (TSS) decreased from 42 to 10 mg/L, 96 to 26 mg/L, and 38 to 10 mg/L, respectively. The suspended biomass concentration, hydraulic retention, and return sludge rate of the plant were 1,600 mg/L, 6.9 h, and 175% of inflow, respectively. During the transition to a steady state in the IFAS plant, the removal efficiency of Caffeine, Gemfibrozil, and Testosterone was found to increase by 41% (15%–56%), 26% (63%–89%), and 65% (19%–84%) respectively, due to enhanced biological degradation. The SBR was found to be more efficient in the removal of ECs, which could be due to the higher concentration of suspended biomass. [ABSTRACT FROM AUTHOR] |
