Study On The Technology Of Concentrated-oil Wastewater Treatment Using Immobilized Bio-film By Pseudomonas Aeruginosa NY3

The source ways of oily wastewater were very extensive, and the compositions ofoily wastewater were complicated, which causes serious harm to the environment andhuman health. Currently, many efficient strains degradated petroleum hydrocarbon werereported, but rarely applied to engineering. with a single efficient strain of immobilizedmicroorganism technology applied to concentrated-oil wastewater treatment reportedvery little. In this thesis, our team used a oil-degraded microorganism named NY3，which have been found before, to developed a fixed biofilm technology of treatmentconcentrated-oil wastewater. It’s very meaningful to improve the efficiency of thetreatment of oily wastewater, simplify the process of the treatment and reduce theprocessing cost.In this thesis, the process of treatment of actual oily wastewater using immobilizedbio-film of NY3strain, the conditions of treatment of concentrated-oil wastewater, thediversity and the possibility of recycle of the bio-film were studied.The research resultsare as following:(1) The strain NY3could grow and immobilize in the LB medium, after51h, forma immobilized bio-film, the biomass could reach447.6mg/g carrier. The pH of oilywastewater was the range of7.5~9.0, the oil removal efficiency of bio-film of the strainNY3was better.Within the salinity range of1%~2%, the degrading efficiency ofconcentrated-oil wastewater could be promoted.(2) When treatment actual oily wastewater(oil concentration was76.7mg/L) usingthe bio-film of NY3, the HRT was10h,8h,6h,4h respectively, oil removal rate were more than90%.Oil content of effluent could meet ‘the integrated wastewater dischargestandard’(GB8978-1996). The optimum HRT for treating high concentrated-oilwastewater (oil concentration is2000mg/L) by immobilized bio-film of NY3strain is12h, the metabolism of biofilm and supply of carbon source achieved basic balance, andthe average removal efficiency of oil could reach80.72%.(3) After treatment the high concentrated-oil wastewater, immobilized bio-film ofNY3strain still has high activity, the biofilm collecting into culture medium withoutpetroleum hydrocarbons was incubated15d, NY3strain on the bio-film degraded aboutmore than90%petroleum adhered on the surface of carrier and the bio-film wasrecovered for recycling.(4) After treatment oily wastewater using bio-film of NY3strain, SEM found thatthere will be mixed bacteria on the surface of carrier after operation60d.PCR-DGGEpreliminary analysis results show that the microorganism on the surface of biofilm hadabiological diversity at the treatment process of oil-bearing wastewater,somemiscellaneous strains in the environment into the biofilm, but the NY3strain was stillthe dominant.The results of the study in this paper lay the foundation for the NY3strain onapplication of oily wastewater treatment.