低渗透压力敏感性储层合理井底流压确定方法

Rational Bottom-hole Flowing Pressure Calculation for Low-permeabilityand Pressure-sensitive Oil Reservoirs

针对低渗透油藏储层普遍存在压力敏感性的问题,为了在采油井工作制度制订过程中考虑压力敏感性的影响,开展了低渗透压力敏感性储层合理井底流压确定方法研究。从原油黏度、体积系数、相对渗透率和储层物性参数与压力关系出发,分别建立了不同条件下的采油井产量计算模型,通过最优化处理,利用国内某低渗透油田储层数据,编制了低渗透压力敏感性储层合理井底流压图版,给出了合理井底流压与含水率及渗透率的关系。结果表明,受渗透率压力敏感性影响,合理井底流压随含水率及渗透率的增加而降低。该方法为低渗透油藏压力敏感性储层合理工作制度的制订提供了理论依据和方法指导。

Low-permeability reservoirs are generally pressure-sensitive.To take into account the effect of pressure sensitivity in the process of making working systems for production wells,the research on the method for determining rational bottom-hole flowing pressure in low-permeability and pressure-sensitive reservoirs was conducted.First,from the correlation among the crude oil viscosity,volume factor,relative permeability and the reservoir prop-erty parameters with the pressure,different well production calculating models under different conditions were established;Second,based on optimum pro cessing and using the reservoir data of a domestic low-permeability oilfield,rational bottom-hole flowing pressure chart for low-permeability pressure-sensitive reservoirs was compiled,and the relationship among the rational bottom-hole flowing pressure,the water cut or permeability was concluded.Re-sults showed that the rational bottom-hole flow ing pressure dropped with increasing water cut and permeability,due to the permeability pressure sensitivi-ty.The new method provided theoretical basis and guidance for compiling rational working systems for low-permeability and pressure-sensitive reservoirs.