Mechanisms of oil displacement by Geobacillus stearothermophilus producing bio-emulsifier for MEOR

ABSTRACTThis paper studies the Geobacillus stearothermophilus SL-1 that is widely distributed in oil reservoirs. We also carried out the emulsification stability experiment of paraffin. The particle size distributions of oil-emulsified droplets from the emulsified bacteria and their metabolites were determined by laser particle size analyzer. Using the glass model of the dimensional microscopic visualization, the oil displacement mechanism and effect of the emulsified bacteria on the remaining oil in the simulated reservoir environment were studied. The results show that the emulsified bacteria and their products can effectively emulsify the crude oil, and can form the large emulsion of a big viscosity with the crude oil during oil displacement, which is helpful to increase the flow resistance of the hyperosmotic channel, improve the ratio of oil to water, and enlarge the volume of the injected liquid. The microbial fermentation has a better effect to enhance the recovery than the metabolites or the micro...