强非均质多层系双高油藏智能分注调控新方法

A new method of intelligent split-injection regulation for strongly inhomogA new method of intelligent split-injection regulation for strongly inhomogeneous multilayer double-high reservoirs eneous multilayer double-high reservoirs

智能分层注水是现代油田注水调控的重要内容,为解决强非均质多层系双高油藏注水开发效率低的问题,利用油藏地质资料和生产数据,提出了针对此类油藏的智能分层注水调控新方法。该方法与传统分注方法不同的是,不需要建立地质模型,只需要通过拟合历史生产动态计算出纵向及平面劈分来完善油田分注方案,从而大大节省数模计算时间。通过对实际生产数据的历史拟合,计算出了纵向及平面的注水劈分,帮助分析多层系油藏不同层间及同一层中不同油井的注水占比情况,同时结合改进的随机扰动近似梯度(simultaneous perturbation stochastic approximation,SPSA)优化算法对油藏进行注采优化。将该方法应用到新疆L9油藏,经预测,实施典型井组调整措施2年后,较之前注水方案,区块累计产油量增加了4.6%,累计注水量减少了3.3%,井区含水率降低了2.6%,效果显著。研究表明,该方法能够有效提高注水利用率,优化油田开发效果,为强非均质多层系双高油藏的智能分注调控提供了新的思路和方法。

Intelligent layered water injection is an important element of modern oilfield water injection regulation.In order to solve the problem of low efficiency of water injection and development in strongly inhomogeneous multilayer system double-high reser⁃voirs,a new method of intelligent layered water injection regulation for this type of reservoirs is proposed by utilizing the reservoir geological information and production data.The difference between this method and the traditional layered injection method is that it does not need to establish a geological model,but only needs to calculate the vertical and planar splits by fitting the historical produc⁃tion dynamics to refine the field splitting scheme,thus greatly saving time.The vertical and planar water injection splits are calculated by historical fitting of the actual production data,which helps to analyze the water injection share of different wells between different layers and in the same layer in multilayer reservoirs,and at the same time combines with the improved SPSA(simultaneous perturba⁃tion stochastic approximation)optimization algorithm to optimize the injection and extraction in the reservoir.Applying the method to Xinjiang L9 reservoir,it is predicted that after two years of implementing the typical well group adjustment measures,the cumula⁃tive oil production of the block has increased by 4.6%,the cumulative water injection has decreased by 3.3%,and the water content of the well zone has decreased by 2.6%compared with the previous water injection scheme,which is a remarkable effect.The study shows that this method can effectively improve the utilization rate of water injection and optimize the development effect of the oil⁃field,which provides a new idea and method for the intelligent split-injection regulation and control of the strong inhomogeneous mul⁃tilayer system of double-high oil reservoirs.