中东碳酸盐岩油藏注水开发思路与对策

Optimum development options and strategies for water injection development of carbonate reservoirs in the Middle East

通过对多个中东已开发碳酸盐岩油藏的研究,厘清了不同类型碳酸盐岩油藏的基本特征,提出了一套高效注水开发方式及技术对策。确定了中东碳酸盐岩油藏多存在比较隐蔽的物性夹层的特征,明确了充分利用隔夹层的发育特点坚持分层系开发的原则。提出采用灵活多样的井型和简单适用的分层注水等剖面控制技术,提高对储集层的控制及动用程度。提出了适用于中东地区不同类型碳酸盐岩油藏的3种主体注水开发方式,包括顶部注气与边缘注水相结合、底注顶采(浮力托浮)和点弱面强面积井网等开发方式。明确了中东碳酸盐岩储集层泥质含量少、压力传播快且远的特征,宜采用大井距注采井网,制定了温和注水、保持合理生产压差及注采比的开发技术对策,以实现油藏无水和低含水期的最大采出程度。

Through the research on several carbonate reservoirs developed in the Middle East, the basic characteristics of different types of carbonate reservoirs are determined, and a set of high-efficiency water injection development options and strategies are presented. Hidden baffles and barriers exist in carbonate reservoirs in the Middle East, so the reservoirs could be divided into different separated development units based on the baffles and barriers characteristics. Flexible and diverse profile control techniques such as high angle wells and intelligent zonal water injection have been introduced to improve the control and development degree of reservoirs. Three principal water injection development methods suitable for different carbonate reservoirs in the Middle East are proposed, including the combination of crestal gas injection and peripheral water injection, bottom interval injection and top interval production （buoyancy underpinning）, and “weak point and strong plane” area well pattern. Based on the characteristics of very low shale content, fast and far pressure transmission in the Middle East carbonate reservoirs, a large well-spacing flood pattern is recommended, and reasonable development strategies have been made such as moderate water injection rate and maintaining reasonable production pressure drawdown and voidage replacement ratio, so as to maximize the recovery of reservoirs in the none or low water cut period.