基于剩余油分布的分层注水井各层配注量确定方法

分层注水开发中,各层配注量的常用确定方法没有考虑小层剩余油分布情况,为此,研究了确定小层配注量的新方法。从生命旋回理论和逻辑斯蒂增长规律出发,推导了采出程度与累计注入水体积之间的定量关系。按照小层剩余储量分布规律,以提高注水波及效率和剩余油动用程度为目标,建立了基于剩余油分布的分层注水井各小层合理配注量计算新模型。运用精细数值模拟方法分析了厚度法、地层系数法和剩余油法分层配注与油田各开发阶段的适应性,结果为:含水率小于50%时,推荐使用厚度法;含水率为50%~80%时,推荐使用剩余油法。研究成果在渤海SZ油田F6井进行了现场应用,应用效果显著,井组含水率下降8%,净增油7 766 m3,表明分层配注新方法及各层配注量确定方法适应性研究成果可用于指导分层注水井各层配注量的优化调整。 

Injection Allocation Determination Method for Separate Injection Well Based on Remaining Oil Distribution

To solve the problem of common injection allocation method in which remaining oil distribution is not taken into account,a new injection allocation method for sub-layer was studied.The quantitative relationship between recovery percentage of recoverable reserves and cumulative injection volume multiple was deduced based on Lifecycle Theory and Logistic Growth Law.According to the distribution of remaining recoverable oil in various su-blayers,a new method of injection allocation for separate injection well based on remaining oil distribution was put forward to improve sweep efficiency and producing degree.Refined numerical simulation was used to study the adaptability of thickness method,formation capacity method and separate injection allocation method to the oilfield development stage.The result showed that thickness method is recommendable when water cut is less than 50%,remaining oil method is prefered when water cut is within the range of 50%-80%.Pilot test was conducted on Well F6 of SZ Oilfield with remaining oil method and showed that water cut decreased by 8% and net oil production increased by 7 766 m3.This indicated that the adaptability research result of the new separate injection and injection allocation determination method can be used to guide the optimized adjustment of the separate water injection.