1 Section for Organismal Biology, Department of Plant and Environmental Sciences, Faculty of Science, Københavns Universitet2 South China University of Technology3 Changzhou College of Information Technology4 Shenzhen University5 South China University of Technology6 Section for Organismal Biology, Department of Plant and Environmental Sciences, Faculty of Science, Københavns Universitet7 Shenzhen University
Sequential upflow anaerobic filter (UAF)/air lift (ALR) reactors were employed to investigate the effects of hydraulic retention time (HRT) and nitrobenzene (NB) concentration on treatment of NB-containing wastewater. The results showed that NB was effectively reduced to aniline (AN) with glucose as co-substrate in the UAF reactor. The AN and the remaining intermediates after the UAF reactor were then efficiently degraded in the ALR reactor. A removal efficiency of 100% and 96% was obtained for NB and chemical oxygen demand (COD), respectively, using sequential UAF/ALR reactors with an HRT of 8-72 h in the UAF reactor and 2-18 h in the ALR reactor. The corresponding optimal influent NB concentration varied between 100 and 400 mg l super(-1) to achieve the optimal NB and COD removal. The NB removal efficiency decreased to 90% and to 97% if the HRT in the UAF reactor decreased from 8 to 2 h and the influent NB concentration increased from 400 to 800 mg l super(-1), respectively. The results showed that sequential UAF/ALR system can be operated at low HRTs and high NB concentrations without significantly affecting the removal efficiency of NB in the reactor system. The UAF/ALR system can provide an effective yet low cost method for treatment of NB-containing industrial wastewater.
Environmental Science and Pollution Research, 2014, Vol 21, Issue 22, p. 12800-12810
Upflow anaerobic filter; Air lift reactor; Nitrobenzene; Aniline; Reduction; Inhibition