Analysis Of Reservoir Influence Factor For Microbial Enhanced Oil Recovery

All EOR technologiesare inseparable from reservoir analysis, including microbial enhanced oil recovery technology. Analysis of the effect factors of microbial enhanced oil recovery from the reservoir perspective and finding possible mechanisms not only has important theoretical value but alsois the current weak link of microbial enhanced oil recovery techniques. Results of the study will lay a foundation for future screening microbial flooding test area in conglomerate reservoir.In the background of microbialflooding field test in Liuzhong District, this paper starts fromdeepening understanding of geological knowledge,and uses three-dimensional seismic data to interpret stratum structure and re-implement fault.Stratums are finely compared using digital log data and connectivity relations among small layers of the study area are re-implemented.Distribution of the reservoir isdetermined and reservoir quality is evaluated by the reservoir sedimentary facies studies. On this basis, geological model of the study area is establishedusing specialized software.The reservoir is re-recognizedby combining geological modeling and production performance.Biochemical indicators and oil increment of test wells are evaluated. Influence of reservoir parameters to biochemical indicators and oil increment of test wellsis obtained such as reservoir structure distribution, reservoir permeability differences, sedimentary facies control, different water content stages of oil wells and different distribution of remaining oil. Thereby, microbial flooding reservoir parameter optimization model is established and screening criteriafor microbial flooding test area in conglomerate reservoir is improved.Some resultshave obtained through the above-mentioned study. Monitoring results of biochemical indicators show that wells with good water injection effectiveness have a high degree of activation of endogenous microbes and high level of acetate metabolism. These wells are mainly distributed in the film flow belt, braided streams and phase spread with good wellcontrol.Fault will destroy the integrity of injection-production patterns and impact effects of water injection, so the test should be selected in areas with little tectonic movement. Areas in which microorganisms can be effectively activated need to have certain recoverable reserves to get a good effect of oil increment. For conglomerate reservoirsin later stage of production, such wells are typically in the upstream waterways and in areas whose dam configuration or injection-production patterns are not perfect, yetreservoir properties are good. Overall, test wells with good effect distribute mainly in areas with good reservoir properties and low water flooding degree. This conclusion has also been confirmed by laboratory experiments.