A novel application of TPAD–MBR system to the pilot treatment of chemical synthesis-based pharmaceutical wastewater

• Published in: Water research (Oxford) 2008-07, Vol.42 (13), p.3385-3392
• Main Authors: Chen, Zhaobo, Ren, Nanqi, Wang, Aijie, Zhang, Zhen-Peng, Shi, Yue
• Format: Article
• Language: English
• Subjects: anaerobic digestion; Anaerobiosis; Applied sciences; Bioreactors; chemical oxygen demand; Computer Simulation; continuous systems; Drug Industry - instrumentation; Drug Industry - methods; Ethanol; Exact sciences and technology; Filtration; industrial effluents; mathematical models; Membrane bioreactor (MBR); membrane bioreactors; Models, Biological; neural networks; Other industrial wastes. Sewage sludge; Pharmaceutical wastewater; Pilot-scale test; Pollution; Simulation model; Two-phase anaerobic digestion (TPAD); upflow anaerobic sludge blanket reactor; Waste Disposal, Fluid - instrumentation; Waste Disposal, Fluid - methods; Wastes; wastewater; wastewater treatment; water flow; Water Pollutants, Chemical - analysis; Water treatment and pollution
• ISSN: 0043-1354; 1879-2448
• DOI: 10.1016/j.watres.2008.04.020

A pilot-scale test was conducted with a two-phase anaerobic digestion (TPAD) system and a subsequential membrane bioreactor (MBR) treating chemical synthesis-based pharmaceutical wastewater. The TPAD system comprised a continuous stirred tank reactor (CSTR) and an upflow anaerobic sludge blanket-anaerobic filter (UASBAF), working as the acidogenic and methanogenic phases, respectively. The wastewater was high in COD, varying daily between 5789 and 58,792 mg L −1, with a wide range of pH from 4.3 to 7.2. The wastewater was pumped at a fixed flow rate of 1 m 3 h −1 through the CSTR, the UASBAF and the MBR in series, resulting in respective HRTs of 12, 55 and 5 h. Almost all the COD was removed by the TPAD–MBR system, leaving a COD of around 40 mg L −1 in the MBR effluent. The pH of the MBR effluent was found in a narrow range of 6.8–7.6, indicating that the MBR effluent can be directly discharged into natural waters. A model, built on the back propagation neural network (BPNN) theory and linear regression techniques, was developed for the simulation of TPAD–MBR system performance in the biodegradation of chemical synthesis-based pharmaceutical wastewater. The model well fitted the laboratory data, and was able to simulate the removal of COD.