一种水驱砂岩油藏采收率经验公式改进方法

针对海上油田开发井距大，储层砂体形态变化大、横向分布极不稳定的特点，在现有水驱砂岩油藏采收率经验公式使用普适性不足的情况下，综合考虑了水驱控制程度及注采井数比对油田采收率的影响，提出了考虑水驱控制程度及注采井数比的采收率随井网密度变化关系表达式。通过渤海油田开发案例验证表明：新公式能够更加科学合理描述海上油田采收率随井网密度的变化关系，并能够进行采收率预测及钻井工作量规划。该研究结果对油田开发方案编制及油田开发效果评价具有指导意义。

A new formula for calculating recovery factor of water drive sandstone reservoir

For offshore oil fields, the development well spacing is large, the morphology of the reservoir sand body changes greatly, and the lateral distribution is extremely unstable. In addition, the existing empirical formulas for the recovery factor of water drive sandstone reservoirs are not universally applicable for offshore use. Therefore, considering the influence of the degree of waterflooding control and the ratio of injection-production wells on the oilfield recovery factor, a new expression of the relationship between the recovery factor and the density of the well pattern is proposed. Through the verification of the Bohai Oilfield development case, it is found that the new formula proposed in this paper can describe the relationship between the recovery factor and the density of the well pattern more scientifically and reasonably. And it can be used to predict offshore oilfield recovery and analyze the distribution of drilling plan. The research results have guiding significance for the compilation of oilfield development plan and the evaluation of oilfield development effect.