复杂断块油藏不规则注采井网平面均衡驱替方法

Equilibrium displacement of irregular injection-production pattern in complex fault block reservoir

杨明 刘英宪 陈存良 崔龙涛 刘学 张伟丰3

中海石油（中国）有限公司天津分公司渤海石油研究院，天津 300459 振华石油控股有限公司，北京 100031 中国石化胜利油田分公司油气销售中心，山东 东营 257000

Bohai Oilfield Research Institute, Tianjin Branch of CNOOC Ltd., Tianjin 300459, China China Zhenhua Oil Co., Ltd., Beijing 100031, China Oil and Gas Marketing Center, Shengli Oilfield Company Ltd., SINOPEC, Dongying 257000, China

由于海上断块油藏的储层边界复杂，平面非均质性强，多采用不规则井网开发，通过注采结构调整以实现平面均衡驱替是改善断块油藏水驱效果的重要途径。文中根据流线数值模拟结果，将不规则注采井网划分为若干渗流单元，每个渗流单元考虑储层平面非均质特征，应用多流管方法计算了渗流单元在不同油水分布模式下的平面波及系数。通过对比每个渗流单元的平面波及系数，评估目前平面驱替效果。针对平面波及系数较小的渗流单元，优化注采压差以提高平面波及系数，从而实现均衡驱替。将该方法应用于渤海南部BZ￣1油田S1砂体注采结构调整，控水增油效果明显。该方法可为海上油田不规则井网的注采结构调整、油田高效合理开发提供理论依据。

Because of complex boundary and strong horizontal heterogeneity, fault block reservoirs are mostly developed with irregular well pattern in offshore oilfields. Adjustment of injection-production structure to improve horizontal displacement is an important way to improve water flooding effect. In this paper, irregular injection-production well pattern is divided into several single injection-production units based on the result of streamline numerical simulation. Considering the characteristics of reservoir plane heterogeneity, the expression formula of sweep coefficient of water flooding area under different oil-water distribution modes in injection-production unit is established by using multi-flow pipe method. The current displacement effect of injection-production well pattern is obtained by evaluating the area sweep coefficient of each flow unit. Aiming at the flow unit with smaller sweep coefficient, the injection-production pressure difference is optimized to achieve the target plane sweep coefficient to approach equilibrium displacement. This method has been applied to the adjustment of injection-production structure of S1 sand body in BZ-1 oilfield in the southern Bohai Sea, and the effect of water control and oil increase is obvious. This method can provide a theoretical basis for the injection-production adjustment of irregular well pattern in offshore oilfields and realize the efficient and reasonable development of oilfield.

10.6056/dkyqt201906016