Pharmaceuticals and personal care products (PPCPs) are the problem of our age and hospital wastewaters are one of the main sources of PPCPs having a concentration range of ng L-1 to µg L-1 Hospital wastewaters are almost untreated before being discharged into municipal/urban wastewater treatment plants (WWTPs) via wastewater networks in Turkey. These WWTPs are not designed to remove complex compounds such as PPCPs, however, a sizeable amount is released into the environment. Some of the PPCPs present a considerable threat for aquatic organisms even at very low concentrations. This study presents the biological treatability of a synthetic musk namely musk tonalide (AHMT) from a raw hospital wastewater under different sludge retention times (SRTs). The treatability of this PPCP was investigated using an anaerobic UASB/aerobic CSTR sequential biological reactor system in laboratory conditions for the first time in Turkey. Effect of different sludge retention times (5; 30; 45 and 55 days) on the removal of AHMT was researched at mesophilic temperature conditions for the biological reactors. COD, SCOD and AHMT yields were determined. Methane gas (CH4) productions and VFA concentrations were also monitored in anaerobic UASB reactor. pH changes, dissolved oxygen (DO) variations and redox potentials (ORPs) were monitored in anaerobic UASB and aerobic CSTR reactors. As a result of the study, increasing of the SRT has a positive effect on COD (94.1%) and SCOD (91.1%) yields at 55 days of SRT in the biological reactor system. Also, biodegradation (in the supernatant) and adsorption (onto biological sludge) removal efficiencies of AHMT were increased at higher SRTs. AHMT was removed 42.3% with biodegradation from the supernatant while adsorption removal efficiency reached 57.5% in the biological sludge at 55 days of SRT for the anaerobic UASB/aerobic CSTR sequential biological reactor system.
Keywords: Biological treatment; Musk tonalide; Raw hospital wastewater; Sludge retention time
Enhanced removal of antibiotics in hospital wastewater by Fe–ZnO activated persulfate oxidation
