阶段水驱指数、存水率理论图版修正及应用

阶段存水率、水驱指数理论图版作为评价水驱油藏效果一种重要模型,在确定油藏合理配水量与井网调整等方面有广泛应用。由于该模型是含有3个未知变量,因此在实际应用运用过程中,我们通常选择控制注采比的大小来确定含水率与存水率、水驱指数的变化规律。运用理论图版对A断块砂岩油藏注水开发进行拟合可以看出该图版无法有效判断注水效果的合理性。这说明理论图版适合性有限。为了更好的确定油藏水驱效果,通过水驱油藏注采经验公式与存水率、水驱指数定义式结合推导出合理注采比下阶段存水率、水驱指数与含水率的表达式,应用新的表达式所得到的理论曲线与实际生产曲线趋势对比,若理论的曲线与实际结果一致,说明水驱有效较好。同时在对A油藏运用过程中,我们还能通过该模型得到油藏水驱开发效果好坏时机,所以相比与理论图版,新模型更加有效、可靠。

Correction and Application of Theoretical Chart of Stage Water Drive Index and Water Storage Rate

The theoretical chart of stage water storage rate and water flooding index is an important model to evaluate the effect of water drive reservoir, and it is widely used in determining reasonable water allocation and well pattern adjustment. Since the model contains 3 unknown variables, we usually choose the ratio of injection production ratio to determine the change law of water content, water storage rate and water flooding index in the practical application. Using the theoretical chart to fit the waterflooding development of A fault block sandstone reservoir, it can be seen that this plate can not effectively judge the rationality of water injection effect. This shows that the theoretical plates have limited suitability. In order to better determine the reservoir water flooding effect, the water flooding reservoir injection production formula and water storage rate, water flooding index definition are combined to derive the expressions of stage water storage rate, water flooding index and water content under reasonable injection production ratio, the theoretical curves obtained by the new expressions are compared with the actual production curves. If the theoretical curve is in accord with actual results, the water flooding effect is good. At the same time, its application in A reservoir shows that we can get the time and opportunity of reservoir water flooding development by this model. Therefore, the new model is more effective and reliable than the theoretical chart.