特高含水期基于渗流阻力的注水层段重组及配注界限确定方法

Recombination of water injection interval and determination of injection allocation boundary based on flow resistance in ultra⁃high water cut stage

针对已进入特高含水期油田注水层段内部的吸水差异和动用程度差异不断增加,原有由渗透率、有效厚度等静态数据决定的注水层段组合及配水方式已满足不了开发后期油田生产需求的问题,建立了基于渗流阻力的注水层段重组和配注界限确定方法,即根据油层属性、沉积相接触模式等特征的差异,对不同层段采用不同的注水方式和注水量,实现不同油层动用更加均衡,提高薄差层动用能力、减缓产量递减的目标。研究结果表明,依据渗流阻力和阻力系数进行注水层段分级可以有效挖掘分层注水潜力。实践表明,该方法有效改善了X开发区典型区块的开发效果,达到了减缓产量递减和含水上升的目的。建立的特高含水期基于渗流阻力的层段组合和确定配水界限方法,可以有效控制产量递减和含水上升,配水方式及调整方法对开发后期水驱油田具有较高的借鉴意义和参考价值。

For oilfield in ultra-high water cut stage,water injection differences and producing degree differences cause contradiction and problems within injection interval.Original method of determining water injection interval combination and water allocation mode by static data of reservoir permeability and net pay thickness cannot satisfy the needs of development in mature oilfield.A new method of water injection interval combination and water alloca‑tion boundary is put forward based on flow resistance.According to the difference of reservoir attributes and contact patterns of sedimentary facies,different water injection modes and water amount are applied for different reservoirs to achieve more uniform producing of different reservoirs,improve producing capacity of thin and poor reservoirs and slow down production decline.The results show that the water injection layer classification based on flow resis‑tance and resistance coefficient can effectively tap the potential of layered water injection.Application shows that this method improves the development effect of typical block in X development zone,slowing down production de‑cline and water cut increase.The method based on flow resistance in ultra-high water cut stage can effectively con‑trol production decline and water cut increase,and the water allocation mode and adjustment method have refer‑ence significance and reference value for mature water flooding oilfield.