Composite Anaerobic Baffle Reactor Treating Nitrobenzene Wastewater

This study used Hybrid Anaerobic Baffled Reactor to treat Nitrobenzene-containing wastewater. The content of the study include the inoculation and habituated of anaerobic sludge; the selection of carrier; the startup of HABR; the performance of HABR for Nitrobenzene-containing wastewater treatment and the effects of the operation parameters on the treatment. The results of the experiment show that:(1) The anaerobic sludge was habituated by the way of low organic load at 30℃. At the habituation period, the mass concentration of nitrobenzene and COD was gradually heighten to heighten organic volume loading.The inoculation sludge was habituated using digestion sludge.The HABR started up successful within 60 days.(2) Activated carbon and gravel which mixed with same volume acted as HABR's carrier. The height of the fixed bed was 130mm, and it occupied 40% volume of reactor area. The highly effective bacteria membrane could be immobilized in three weeks. The startup of HABR was success.(3) The optimum technological parameters were defined, when the pH of the wastewater was 7.0, organic volume loading was 2.82kgCOD_cr/(m³Â·d), and the HRT was 24h, the removal rate of nitrobenzene and COD_cr was above 92.9% and 80.2%.(4) Among all the factors affecting the running of HABR, organic volume loading has strong effect on the removal of the main pollutants. The removal rate of nitrobenzene and COD_cr was shortened when organic volume loading heightened; too much organic volume loading will lead to too much VFA and acid product, the performance of HABR will go bad.(5) BOD₅/COD_cr changed from 0.28 to 0.42. It is indicated that the biochemical treatability is obviously improved, which accelerates the process of subsequent aerobic treatment.(6) HABR is improved from ABR. It had better performance on the removal of the main pollutants.It is proved by practice that the Hybird Anaerobic Baffled Reactor which is used to treat the wastewater containing nitrobenzene is reasonable and feasible, and it has abroad popularization of applicable value.