| Coal gasification wastewater was a high concentration and nonbiodegradable organic wastewater, and one of serious damagable industrial wastewater. Phenolic compounds are among the most important organic pollutants, toxicity, nonbiodegradable. Treatment methods of phenolic wastewater are primarily divided into three categories: physical, chemical and biological treatment. Compared to the other two types of methods, biological method take advantage of economic, high efficiency and no secondary pollution, has become one of the most widely used ways of wastewater treatment currently. The number of effective microorganisms and concentration are key factors for biological treatment efficiency, therefore, efficient screening of super phenol-degrading bacteria technology has caused people's attention increasingly.The article takes cultivation of high efficient bacteria as research object. And takes activated sludge of gasification plant as the bacteria source. At 30 degree of temperature, number of revolution 120r/min concussion cradle,resorcinol and m-cresol can be used as the sole source of carbon respectively, after domestication and screening, we isolated two groups of strains, which are named JS-4,JD-2 respectively, thus had been two advantageous colonies at last.The article conducted some experiments toward dominant resorcinol-degrading strain under the different density resorcinol wastewater. Results showed that JS-4 with resorcinol content was 500 mg/L, 1000 mg/L, 1500 mg/L and 2000 mg/L, removal rate of resorcinol reached 77.62%, 55.24%, 47.78% and 48.25% respectively. At the same time, the speeds of degrading resorcinol improved gradually, were 129.367 mg/L,184.133 mg/L,238.9 mg/L and 321.63 mg/L respectively. Therefore, we knowed that JS-4 bacteria, not only showed high degradation ability of resorcinol, but also had powerful anti-shock loading capability.Through the test of m-cresol degradation by JD-2 bacteria, we found that 1000 mg/L was the maximum endurable concentration of m-cresol for obtained bacteria. Results of m-cresol degradation experiment showed that higher degradation ability with the content of m-cresol reached 300 mg/L,500 mg/L and 600 mg/L. JD-2 bacteria could degrade 700 mg/L m-cresol and the degradation of m-cresol was 29.65% within 36 hours.According to physiological and biochemical results of the strains of JS-4 and JD-2, with the analysis of 16SrDNA sequence alignment, we could identify this two high-efficient degradation bacterica as Acinetobacter sp. and Pseudomonas sp. respectively.Effects of inoculation quantity, temperature, pH and concentration of carbon source on phenol components removal rate had been studied. Analysis of consequence of orthogonal test, we could see that the temperature had the greatest impact on phenol components degradation by two strains. We also had done some research on phenol components degrading by single strain and mixed strains of JS-4 and JD-2 in raw water, results showed that, in the first six hours, phenol-degrading efficiency of single strain JS-4 was better than mixed strains, after a period of adaptation, mixed strains showed higher biodegradability.
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