地层原油体积系数是油气藏储量计算的重要参数。由于直接确定体积系数的压力—体积—温度(Pressure-Volume-Temperature，PVT)实验法易受样品代表性影响、成本高,现场常采用经验公式法预测。富满油田奥陶系碳酸盐岩油藏具有超深、高温、超高压、不同区块间流体类型多样化的特征,现有体积系数计算经验公式误差大。针对这一问题,在对现有体积系数经验公式适用条件分析评价的基础上,建立了富满油田奥陶系碳酸盐岩油藏黑油和挥发原油饱和压力及地层条件下体积系数预测经验公式,经与PVT实验值比较,经验公式计算的饱和压力及地层条件体积系数相对平均误差均小于5%,满足油田开发、生产管理要求。研究结果对塔里木盆地类似高温、超高压地层原油的体积系数有借鉴意义。

The formation volume factor of crude oil is the key parameter for oil and gas reservoir reserves calculation. Due to the susceptibility of the PVT(Pressure-Volume-Temperature) experimental method to sample representativeness and its high cost, empirical equations are commonly used in the field to predict volume factors. Fuman Oilfield, with its Ordovician carbonate reservoirs, is characterized by wltra-deep, high temperature, ultra-high pressure, and diversified fluid types across different blocks, leading to a poor performance when using existing empirical equation to predict oil volume factor. In response to this issue, after analyzing and evaluating the applicable conditions of the existing volume factor empirical equations, we have developed empirical formulas to calculate the saturation pressure and volume factor of black oil and volatile oil under formation conditions in Fuman Oilfield Ordovician carbonate reservoirs. By comparing with PVT experimental saturation pressure and formation oil volume factor, the average prediction errors were all less than 5%, which satisfied the demands of oilfield exploitation and production management. The research results offer valuable insights for determining the volume factors of crude oil in high-temperature, ultra-high-pressure formations of the same nature within the Tarim Basin.