The use of batch and extended aeration activated sludge system for the investigation of the removal of nitrobenzene from wastewaters

The pollutants that creating great danger to ecosystems have generally organic and inorganic components. Among these materials, Nitroaromatic components forming pollution from organic matter compounds have high toxicity and microorganisms, plants, animals and people are able to show toxic or mutagenic effects. Nitrobenzene (NB) is one of these Nitroaromatic compounds. An important part (95-98%) of NB are used in the synthesis of aniline, a portion of the rubber, soap, pesticides, shoe polish, paint, paint solvents and the pharmaceutical industry. In this study, treatability of NB was investigated using a continuous flow extended aeration and batch activated sludge system. The study was performed under laboratory constant conditions. In the study, synthetic wastewaters that contain various nitrobenzene concentrations were subjected to the system. NB concentrations of synthetic wastewater were between 1-800 mg/L and hydraulic retention time was used as 24 hours. Influent COD concentrations were 380 ± 20 mg/ L at the start of the study. COD concentrations of influent wastewater increased with the addition of NB. Removal rates were between 85-92%. The aim of this study is demonstrate the NB removal capability of the extended aeration activated sludge system.Key Words: Activated sludge, Nitrobenzene, Batch reactor, Nitroaromatic compounds, Continuous flow reactor.