3rd International Congress on Recent Innovations in Engineering, Science and Technology - Istanbul - Turkey (2022-06-24)

Treatment of pharmaceutical wastewater by combining electrochemical process and activated sludge culture
The occurrence of human and veterinary antibiotics in the aquatic ecosystem becomes a serious environmental problem. These compounds cannot be treated by wastewater treatment plants, resulting in their entry and accumulation in the environment. Over the last decade, the conventional biological processes were used for wastewater treatment, but did not appear to be enough effective when dealing with wastes containing antibiotics, owing to the important recalcitrance of these compounds. Therefore, the development of efficient methods to treat antibiotics is needed. In the present study, a combined process coupling an electrochemical process and a biological degradation was investigated in order to treat pharmaceutical wastewater containing trimethoprim (TMP), a bacteriostatic antibiotic regularly detected in the surface water and groundwater. Electrochemical process was used as a pretreatment to oxidize TMP. Experimental results showed a total trimethoprim removal, while mineralization remained limited, 12% for 30 min electrolysis times. Biodegradability was improved, since the BOD5/COD ratio increased from 0.11 initially to 0.52 after 60 min electrolysis times, confirmed by activated sludge culture, 68% overall mineralization yield. The relevance of the proposed combined process was then confirmed on an industrial pharmaceutical effluent. Its electrolysis showed an almost total removal (98%) of TMP, while TOC removal remained low, 14 % for 180 min reaction times. Overall removal yield of the industrial effluent was 80 %, after activated sludge culture.
Dr. Dorsaf Mansour