The Production Change Law Research Under The Elastic Development Of Low Permeability Reservoir

The development of low permeability reservoirs has become the emphasis of oilfielddevelopment in China, the proportion of the total proven reserves in low permeability reservesbecomes more and more. Half of China’s proven reserves is from low permeability reservoirs.But at the same time, because of the characters such as low porosity, low permeability, thelow initial oil saturation, inactive edge and bottom water and serious heterogeneity.etc, thedevelopment of low permeability reservoirs becomes more difficult.In this article, through experiment and the porosity, permeability and initial watersaturation data of Daqing oil field, the porosity, permeability,initial water saturation andpressure sensitivity features of low permeability reservoirs are analyzed; under the Elasticdevelopment of low permeability reservoir, influence factors of elastic production rate,productivity index and inflow performance relationship are simulated with the Eclipsesoftware, and pressure sensitivity are considered in the software calculation, to analyze theinfluence of pressure sensitivity on the reservoir elastic capacity; From the perspective ofelastic production rate, elastic energy supply situation of low permeability reservoirs, and theinfluence of different injection-production method on oil well productivity are analyzed andwell pattern arrangement, injection-production ratio and injection timing in low permeabilityreservoir development are optimized. The results show that the composite compressibility,volumetric coefficient and the parameters that influence geological reserves all have an effecton the elastic production rate; The oil producing capability of low permeability reservoirs aremainly impacted by the permeability, oil viscosity and other physical parameters; elasticenergy supply of Low permeability reservoirs is weak, if under the natural depletion, reservoirpressure would decrease rapidly, the reservoir elastic recovery rate is low; The dramaticallydecline of reservoir pressure makes the permeability become smaller as the impact of pressuresensitivity of low permeability reservoirs, it will seriously affect the reservoir oil-producingcapability, so for the low permeability reservoirs, It is very necessary to timely supplementthe formation energy, maintain formation pressure and choose rational injection-productionwell pattern, injection-production ratio and injection timing. Through software simulation,using5-spot or inverted9-spot injection-production well pattern, injection-production ratiowas between0.9~1.2, advanced water injection for increasing the formation pressure can gethigh recovery degree.