The Composition Of Pollutants And Degrading Bacterial Community Diversity In The Waste Drilling Fluid

This study investigated the organic contamination in the waste drilling fluid from PingHu Oilfield by using GC-MS. The result showed that the pollutants contained hydrocarbons, acids and esters. The bacterial 16S rRNA gene clone library was constructed to detect the hydrocarbon-degrading bacterial community diversity in the waste drilling fluid. The phylogenetic analysis indicated that most of clones were clustered inβ,γ-Proteobacteria with the phylotypes belong to y-Proteobacteria accounting for 78.6% of the clone library, and related to Achromobacter sp., Acinetobacter sp., Alcaligenes sp., Chromohalobacter sp., Halomonas sp., Serratia sp. and Pseudomonas sp.. The sequences closely related to moderate halophile Chromohalobacter sp. and Halomonas sp. were dominant in the bacterial community. The hydrocarbon-degrading bacteria was isolated from the waste drilling fluid and evaluated by 2,6-DCPIP combining GC method. The bacteria identified as Pseudomonas sp. had a good effect on the degradation of the pollutants. The results improved the knowledge of petroleum contamination and hydrocarbon-degrading bacteria diversity in the waste drilling fluid, which might have a potential application in the bioremediation of the waste drilling fluid.