Study on the Selection of Complex Microbial Inoculants for Petroleum Degradation

We select three strains of high efficient oil degrading strains from 30 soil samples,i.e.the DCH-16,DCH-19 and DCH-20.Seven days later,the oil degradation rate turns to 75.6%,80.3% and 73.2%.The three strains are identified as the fatty acid bacillus Alicycolobacillus,Bacillus Sporomaculum and Bacillus Halobacillus.Thereafter,we use the three strains of high efficient degradation bacteria for the crude oil compound experiments.The result shows that the compound bacteria has much better efficiency than single bacteria,and the optimized condition for DCD-19 and DCH-20 is that: the inoculation ratio gets 1:1 with total inoculation 10%,the pH value is 7.5,the concentration of substrate is 20mg.mL-1,and the temperature reaches 35℃,then the degradation of crude oil will be 7 days.Further more,we introduce part of the microbial inoculants into the refinery wastewater treatment of Shenghua refinery.The compound DCH-19 and DCH-20 shows the best performance of petroleum degradation which is up to 80.2%.