Primary Study On Constructing Microorganisms Group Of Lubricant-Castor And Its Bioremediation Function

Based on soil pollution of lubricant-castor in DaGang oil field, six strains of bacteria were isolated by lubricant-castor as sole carbon source, and the roles of biosurfactants involved in bacterial strategies for accessing lubricant-castor were investigated. Based on studies testing the effectiveness of environmental and biological factors on oil degradation of six strains and analysis difference of degradation for components of lubricant-castor by six strains, we constructed a high-effective microbial consortium, through the studies on it’s ecological restoration, initially developed a measure of the ecological bio-degradable lubricant effect of test method, and it will be applied to offered theoretic reference for petroleum contaminated bioremediation. The main study results are as follows.The study of degradation characteristic of the high-effective microbial consortium indicated that the optimal cultivation parameters for temperature and pH were determined as30℃and7.0. Through the experiments of CEC L-33-A-93, optimal conditions for lubricant-castor degradation were studied:temperature30℃, pH7.0, inoculation10%, and shaking speed180r/min. After optimum, degradation rates of lubricant-castor could reach84.86%.This experiment compared the three kinds of surfactants on degradation of high-effective microbial consortium of lubricant-castor, the results show that, non-ionic surfactant Tween-80can be better to promote the degradation of lubricant-castor, the proper concentration of Tween-80is600mg/L. Surfactants in the selected conditions, we select the temperature, pH, N quality concentration as the change factors, high-effective microbial consortium as the research object, set up a group of four factors and three levels of the orthogonal test, studied the effects on various environmental factors of the degradation rate and biomass. In the experiment the four factors on the lubricant-castor degradation rate were temperature> N concentration> pH.Added the high-effective microbial consortium to the soil polluted by lubricant-castor for biological repairing, with soil respiration intensity and biological activity of change as indicators of bioremediation, the results showed that during the process of40-day bioremediation, the degradation rate was improved by38.20%compared with that in nature condition.The soil samples analysis of variance of indicators can be seen that two kinds of soil respiration rate and changes in oil content significantly different (p<0.05), plus bacteria bioremediation of soil strength significantly larger than that without bacteria with soil samples.