Studty On Enhancment Of The Compound Microorganism Bioremidation Of Oily Soil By Electric Field

A large of oil and its byproduct enter into the environment has caused the durability of the soil and groundwater pollution,the harmness should not to be ignored. remediation of the contaminated soils is extremely urgent. This study is based on the selecting of the efficient and compound microorganism,The best mode of electric field is studied and the influence factors of microbial degradation of oily soils is researched during the optimalelectric field,which makes the electric field enhanced bioremediation of oily soil best.The conclusion is as follows:(1)The p H value of Changqing oil field oily soils is neutral and weak alkali, moisture content below 10%, particle diameter of the main distribution between 5 and 20 microns. All kinds of element content is rich, element of C is up to 59.77%, the N and P is very low.(2)5 kinds of efficient oil-degrading bacteria are isolated from the oily soil, which grow quickly and reach the maximum number in 30 h. The p H value is increased by 4-5 point after culturing 6 days. W-1,W-2, W-3,W-4 and W-5 belong to Zooqloea sp., Alcaligenes Castellani & Chalmers sp., Bacillus sp., Flavobacterium Bergey sp.and Pseudomonas sp.(W-2、W-5)are the best compound strains mixed as 1:1.(3)When the way of electric field is direct insertion, electric field strength is 100 V/m, graphite is the electrode, the remediation effect is best and oil-degrading rate as high as 89.29%, 87.01% and 89.21%. Under the action of electric field, the soil moisture content should be 45%.(4)The effect of the physical and chemical properties of the soil samples and microorganism is small under the electric field, the degradation and migration of oil is small,too.The electric field of 100 v/m is the best on the growth of bacteria; the range of dehydrogenase activity can improved between 25% to 45% and the highest enzyme activity is up to 548 mg·L-1h-1. the capacity of oil-degrading increased between 12.1% and 16.2% by single bacterium, W-5 is highest up to 16.2%.(5)Under the optimal conditions, the effect of electric field enhancing compound microorganism bioremidation of oily soil is obviously higher than pure bioremediation effect, which oil-degrading rate is 22.21% higher than pure bioremidation rate.