Co-metabolism Research On The Degradation Of Aniline Aerofloat In Flotation Wastewater By SBBR Method

The flotation wastewater has the characteristics such as large amount of water, high toxicity and others, before discharge standard or reuse must be treated effectively, otherwise it will bring serious pollution to the environment. Aniline aerofloat as a good collector is widely used in the flotation technology of lead-zinc sulfide ore, but its hydrolysis is very slow in normal temperature, and it have brought great trouble to the treatment of flotation wastewater. In the laboratory conditions, co-metabolism biodegradation of aniline aerofloat was studied by using self-made SBBR, the co-metabolism degradation effect of aniline aerofloat with single and mixed substrates were discussed mainly after determined the optimal operating conditions of the SBBR reactor, and on this basis, the characteristics of co-metabolism degradation of aniline aerofloat in SBR and SBBR reactors were compared, and the main conclusions were as follows:(1)Experiments used simulate wastewater containing aniline aerofloat to hang membrane by artificiality, and the reactor hanged membrane successfully through70days domesticated and cultivated. The optimal operating conditions for SBBR were:5.0h aeration, aeration quantity9L/min, pH about6.5, substrate concentration about150mg/L,1.0h settling. And under the best conditions, the SBBR optimum filling rate was30%, the effluent COD was46.57mg/L and the removal rate was83.41%; aniline aerofloat concentration was22.49mg/L and the degradation rate was85.19%.(2) The glucose, sucrose, amylum, vitamin C and sodium acetate as the plus substrates with aniline aerofloat to co-metabolism degrade based on the SBBR reactor completely domesticated and with a good biodegradability, the results showed that different plus substrates and dosage ratio had a great effect on the degradation of aniline aerofloat in SBBR reactor. Especially when the dosage ratio of plus substrates and aniline aerofloat was1:1,5plus substrates showed a certain role in promoting on degradation of aniline aerofloat, and the removal rate of effluent COD reached above85%, the degradation rate of effluent aniline aerofloat reached above91%.(3) Keep the inlet concentration of aniline aerofloat about150mg/L, studying the co-metabolism degradation of aniline aerofloat with single plus substrates. Under the certain dosage ratio condition, the degradation of aniline aerofloat in the reactor could show a better role in promoting when the glucose, sucrose, amylum and sodium acetate as single plus substrates with aniline aerofloat to co-metabolism, while the vitamin C as plus substrates, promote role was very limited, mostly showed inhibitory effect. Especially the reactor could obtain the best effect of effluent when sodium acetate and aniline aerofloat with the dosage ratio of1:2to co-metabolism degrade, and the effluent COD and aniline aerofloat concentrations were21.67mg/L and5.72mg/L, the corresponding removal rate and degradation rate were91.99%and96.14%. (4) Keeping the plus substrates and aniline aerofloat dosage ratio was1:1, and added different mixed substrates with aniline aerofloat to co-metabolism degrade, the results showed that the glucose and sodium acetate as mixed substrates, and the dosage ratio with aniline aerofloat was (2:1):3, the reactor could obtain the best effect of effluent, the effluent COD was32.98mg/L and the degradation rate reached92.21%, aniline aerofloat concentration was14.73mg/Land the degradation rate reached90.10%.(5) Keeping the dosage ratio was1:1, and running under the same conditions, the effect of aniline aerofloat co-metabolism in SBBR reactor was much better than the SBR reactor, the effluent COD removal rate and aniline aerofloat degradation rate of SBBR were above85%and91%, while the SBR effluent COD removal rate was below80%, the degradation of aniline aerofloat was less than80%. But it needed more time to reach the co-metabolism degradation balance, usually within5.0hours, while the SBR achieved the balance was usually within3.0hours. In addition, sodium acetate as the co-metabolism substrate could improve the degradation rate of aniline aerofloat.