Screening Bioemulsifier-produced Microorganisms And Its Physical Simulation Experiment Studying In Zhan3Block Of Shengli Oilfield

Microbial enhanced oil recovery technology （MEOR） is a kind of more respectedEOR technology in the world. It mainly has a wide range of applications,environmental compatibility, good biodegradability, low-cost, simple operation andother advantages，which may become the most potential technology for oil recovery.With the development of modern technology and the expansion of the research team,microbial enhanced oil recovery technology has been constantly developing andimproving. On the basis of activating endogenous microorganisms that from dip3block in the Shengli oilfield, the microorganism that could produce emulsifier wascollected for analysis its genus and metabolites （emulsifier）, and evaluated theirculture conditions and temperature salt-tolerant performance evaluation. Finally, bydoing the physical simulation of flooding experiment to investigate different gasdistribution quantity and different incubation times and their influence to enhancingthe oil recovery rate. This study provides a new microorganism for increasing therecovery rate and also provides a theoretical reference data for its application in thefield of microbial enhanced oil recovery.（1） Select and identificate the microorganism that could produce emulsifierBy doing Activation experiment for water samples of dip3blocks to determinethat the water samples contain the microorganism that could produce emulsifier.Usethe means of cloning and sequencing analysis to determine that the microorganism isAeribacillus or Geobacillus species. And finally the microorganism that couldproduce emulsifier was identified as Geobacillus by doing the experiments which hadphysiological and biochemical properties, analyzing for16rSDNA and establishingthe phylogenetic tree establish, and named PZ-1.（2） The identification of the product of the PZ-1 Used the means of thin layer chromatography, Coomassie brilliant blue andinfrared spectroscopy to analyze the bio-emulsifier and found that the importantcomponents of the bio-emulsifier are carbohydrates and protein. The contents of thecarbohydrates are between31.23%and38.58%. The main components of thecarbohydrates are an oligosaccharide and a small amount of glucose by usinghigh-performance liquid chromatography analysis. After the carbohydrates werehydrolyzed,and the main products obtained are lactose, glucose, rhamnose, mannoseand so on. The contents of the protein are between14.03%and19.96%, and the maincomponents are macromolecules protein（26.0KDa）. After the samples werehydrolyzed by L-8900automatic amino acid analyzer, and the main products obtainedare Asp, Glu, Tyr, Ala, Leu, and other amino acids. Due to the limitations of themethod used, the peptides were not found in the products. In summary, the emulsifierthat PZ-1produced is a kind of exopolysaccharide which contains polysaccharidesand proteins after preliminary identification.（3）Select the best medium for PZ-1and optimal conditions for the physicalsimulation flooding experimentThe best medium and culture conditions were obtained by gradual optimising.The compositions of the best medium are as follows：sucrose20.0g/L, yeast extract5.0g/L, corn steep liquor0.5g/L, NaNO₃4.0g/L, KH₂PO₄4.0g/L, NaH2PO43.0g/L; The optimal culture conditions: temperature55°C, pH=7, salinity10g/L.On the basis of the best medium, PZ-1had better emulsifying effect on crude oil whenPZ-1was cultured15days by analysis the effect of the laboratory dynamicemulsification crude. Then the crude oil particle diameters are between5and20μm.In the physical simulation of oil flooding experiments, gas distribution quantity andincubation times of the strain PZ-1are optimalled, the results are as follows:when thevolume of joining gas is15times of joining culture medium,and the incubation timeof PZ-1reach20days,microbial enhanced oil recovery can reached a maximum of8.5%, which showed good oil flooding performance.