| The antibiotic wastewater is one of industrial sewage that generally acknowledged toxicity strongly, deal difficultly in the world. Based on the analysis of the international membrane biotechnology and the shortcoming of conventional activated sludge system, SBMR(Sequencing Batch Membrane Reactor) was investigated for antibiotic wastewater. The system combines the membrane bioreactor organically with sequencing batch reactor.In this research, SBMR adopts two operating modes. In the first mode, the reaction step only consists of aerobic process. In this mode, we have studied the characteristic of the SBMR. The influence factors including pH, volume loading and temperature were investigated in this stage. In the second mode, in order to enhance the efficiency of the denitrification, "anoxic-aerobic-anoxic-aerobic" process was studied. The results we have achieved in the study are following:(1) In the first work mode, the 16 hours aerobic time was determined. In this system, average removal rations of CODcr, BOD5 were 88.6% and 95.3% respectively. The efficiency of nitrification has increased along with running time and the removal ration of NH3-N was up to 82.6% at most.(2) pH8.0~8.5 was the better suitable parameters. The ration of fill-in/effective volume of reactor, volume loading should below 0.7 and 0.1 kgNH3-N/(m3·d) respectively. Under the low temperature, the removal rations of CODcr, NH3-N were 84.6%~88.9%, 72.4~78.8% respectively. Nitrobacteria influence by temperature greatly and the membrane filtration of NH3-N fluctuate greatly.(3) In the "anoxic-aerobic-anoxic-aerobic" process, the volume loading 0.765~0.853kgCODcr/m3·d, the removal rations of CODcr, NH3-N, TN were 87.9%~90.8%, 79.99%~84.17%, 62.70%~67.57% respectively. Compared with the average removal rations of TN 40.17% in first mode, the rations of TN increased greatly.(4) Under SRT125d,MLVSS/MLSS keeps in 0.73~0.79. This proved that the inorganic matter has not accumulated in the reactor. The specific oxygen uptake rate of endogenous respiration was 2.62~2.98mgO2/(gVSS·h) that indicated the activity of microorganism is high.(5) When the Rotatoria breed in a large amount in the reactor, the sewage disposal result is good. The average particle size in the SBMR smaller than in the CAS.(6) Adopted 1% sodium hypochlorite and 2% citric acid soaking membrane package 12h sequentially, the membrane was washed effectually and the flux of membrane resumes 82.4%. |
