聚合物驱油田可采储量计算方法

为了改进聚合物驱（聚驱）油田可采储量的计算方法，利用聚驱驱替特征曲线，对大庆油田萨北开发区的19套井网进行研究，发现一类与二类油层聚驱可采储量的计算方法是一致的，只是在不同开采阶段采用的方法不同。在聚驱后续水驱阶段，水驱规律曲线表现出明显的直线特征，可采用修正甲型和丙型水驱规律曲线计算聚驱可采储量、标定可采储量、空白水驱可采储量和聚驱增储结果等；在聚驱中后期阶段，通过计算出的累积产油量，利用历史数据预测转后续水驱的累积注水量，即可计算出整个聚驱过程中的聚用量，并可分析后续水驱阶段的采出程度，从而建立起中后期可采储量的计算模型；在聚驱早、前期阶段，对于还未注聚的区块无法用驱替曲线进行可采储量预测，因此采用多元回归的方法，从影响聚驱效果的主要因素出发，回归了聚驱可采储量的计算模型，根据注聚前设定的注聚方案参数就可以进行可采储量的预测。应用实例表明，该方法可精确计算聚驱油田不同阶段的可采储量，其计算平均误差仅为1.96%。

Calculation method of recoverable reserves in polymer flooding field

In order to modify the calculation methods of recoverable reserves of polymer flooding oilfield, a study is carried out on 19 sets of well pattern of Sabei development zone by using polymer displacement characteristic curve. The results show that the calculation methods of polymer flooding recoverable reserves are consistent for both the first class reservoir and the second class reservoir, whereas different methods are adopted in different development stages. In subsequent water flooding stage of polymer flooding, the water flooding curve shows obvious linear characteristics, so polymer flooding recoverable reserves, rate recoverable reserves, blank water flooding recoverable reserves and the augmentation of polymer flooding recoverable reserves can be calculated; in the mid-late stage of polymer flooding, through the calculated cumulative oil production and prediction of subsequent water flooding cumulative water injection with the historical data, the polymer dosage in the process of polymer flooding can be calculated and recovery degree of subsequent water flooding stage can be analyzed, then the calculating model of recoverable reserves can be establish; In the early stage of polymer flooding, recoverable reserves cannot be predicted by using displacement curve with the blocks which have not polymer injection. From the main influencing factors of polymer flooding, the calculation model of polymer flooding recoverable reserves is established with the method of multiple regression, thus recoverable reserves can be predicted according to polymer flooding injection scheme parameters. Application examples shows that this method can accurately calculate the recoverable reserves of polymer flooding in different stages, and the average error is only 1.96%.