Habr-sbr Treatment Of Nitrobenzene Wastewater

Nitrobenzene wastewater,as a kind of toxic and non-degradation matter,is hard to treat in industry.And many countries categorize it as a priority-pollutant.The combined anaerobic-aerobic system(HABR-SBR process) was operated for treating wastewater containing low concentrated nitrobenzene.HABR was investigated in this thesis,including domestication of anaerobic sludge,filler choice,film startup of reactor,research on impact parameter and so on.The main impact parameters contain COD,volume loading, nitrobenzene concentration,VFA and pH.The results showed that:(1) The anaerobic sludge was domestic in the way of low loading.During the process of startup,increasing the concentration of COD was used to improve the organic volume loading of system.The HABR started up successful within 60 days.Sphere of plastic acted as HABR's carrier.The height of the fixed bed was 120mm,and it occupied 40%volume of reactor area.(2) Nitrobenzene wastewater was treated optimal when the optimum technological parameters of HABR were defined,which the HRT was 16h, volume loading was 4.05kg COD_Cr/(m³Â·d),pH was 7.0,NH₄⁺ was 80 mg/L and salinity was 5g/L～10g/L.Under these conditions,the removal rate of nitrobenzene and COD_Cr was 92% and 45%,respectively.(3) Fe,Co and Ni,which have significant effects on anaerobic digestion system,have been chosen to study the impacts on anaerobic digestion system.The results indicated that Co,Ni,Fe had a significant promotion to anaerobic digestion of nitrobenzene wastewater,while the sequence of their effect was Co＞Ni＞Fe,and the optimum combination was Co²⁺ 0.05mg/L,Ni²⁺ 1.0mg/L and Fe²⁺ 2.0mg/L.(4) The SBR started up successful within 25 days.And the optimum technological parameters of SBR was defined,when DO was 2 mg/L,the HRT was 12h.(5)After 7 days' experiment of stability, the removal rate of nitrobenzene and CODer was above 95%and 97%,respectively。It was proved that anaerobic-aerobic process which was used to treat the wastewater containing nitrobenzene was reasonable and feasible,and it has had broad popularization of applicable value.