| Due to the wide use of petrochemical products, the factory produced large amounts of high oil concentrations waste water. Despite the researchers have isolated a wide variety of oil bacteria, there is more difficult in the conventional oily wastewater treatment in different HRT. Our group previous isolated an excellent hydrocarbon-degrading bacteria, resistant to high concentrations of oil, and the oil can be the sole carbon and energy source. In this paper, we based on previous studies and researched the characteristics of dealing with high concentrations of oily wastewater by immobilized biofilm of bacteria NY3, and studied the characteristics of degradation process and natural compatibility on the microbial biofilm, to find in the good bacteria which can be collaborative during degradation process of oil.In order to study the oil removal rate and the microbial diversity of membrane surface, we used renew operation mode to deal with the high concentration of oily wastewater by biofilm of bacteria NY3, and by the method of scanning electron microscopy(SEM), gas chromatography, the weight method and molecular biology tools, then obtained the following results :(1) Immobilized biofilm of bacteria NY3 has the ability to carry biomass up to 460 mg dry bacteria/g polyurethane. Under the condition of that The oily water samples concentration of 2g/L, HRT 24 h, biofilm continuously runned 25 d, oil hydrocarbon removal rate kept at the range 83-95%.The higher the membrane surface biomass, more stable operation, high oil removal efficiency.(2) Running 60 days, accumulation of biofilm surface,for the most part was branched hydrocarbons and aromatics. Aeration allows gradual degradation of contaminants on biofilm accumulating 60 days, more NY3 bacteria liquid can accelerate recovery of the biofilm. In addition to the biofilm recovered 9-15 d then oil hydrocarbon removal rate kept the range of 80-100%, so biofilms can be recycled.(3) As the extension of time, the microbial diversity of the membrane surface was increasing. the cultured bacteria identified by using 16 S r RNA as Rhodococcus.FF,Staphylococcus.LH, Bacillus.MH, Solibacillus.FB.(4) The four cultured bacteria which could survived on the immobilized biofilm was Rhodococcus.FF, Staphylococcus.LH, Bacillus.MH, Solibacillus.FB,all has the good features of degradating crude oil, underwater oil 2g/L, running 3 days,the average degradation rate of the components of crude oil were 95.7%, 87.9%, 55.3%,75.7%. Rhodococcus FF which can efficiently degrade C11-C32 hydrocarbons. |
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