The Screening Of Salt-tolerant Strain And Their Application In Treatment Of Hypersaline Wastewater

With the accelerated process of industrialization, the high salinity wastewater of the impact on the environment paid more and more attention to. The high salinity wastewater that untreated to discharge caused great pollution for drinking water, the water of industrial and agricultural production, rivers, lakes and other water bodies. Diluting the high salinity wastewater, improving the utilization of waste water can effectively relieve the water pressure today. So the high salinity wastewater treatment has become one of the research focuses in the wastewater treatment.This paper screened four salt-resistant strains that can grow in the condition of the salinity was10%were screened form fifteen strains by setting different NaCl concentration gradient. Its object of study, observed the morphologyCof salt-tolerant bacteria. Studied the impact of different environmental factors (salinity, pH, temperature, etc.) on the four strains grown and studied the changes of bacteria in the nitrogen source, carbon source, pH and other factors in the growth process.By the practical application of the high salinity wastewater, studied the COD removal efficiency in the single strain and the combination strains, the treatment effect of the combined strains under different pH conditions. And16srDNA sequence homology analysis of the two strains.Studied found that:14strains, including four strains1-7,2-5,2-6,2-7can grow in the condition of12%inorganic salt. They can grow best at a temperature of25℃, pH6-7. The highest removal rate of1-7to NaCl was56%.2-5and2-7in salt concentration is5%,10%under the conditions of erythromycin, etc all can produce resistance. Through the waste water containing salt in the practical application, the best COD treatment effect of single strain2-7were22.93%. The best COD treatment effect of the combination strains2-6+2-7were40.5.%in the condition of pH7.5.To the strains of the two strains16srDNA sequence homology analysis.2-6Bacillus cereus and homology is as high as100%.2-7the homology and Bacillus sp homology is as high as100%.2-6and2-7belongs to bacterium Bacillus.