苏北盆地溱潼凹陷草舍油田CO混相驱技术研究

STUDY OF CO MISCIBLE FLOODING TECHNIQUE IN THE CAOSHE OIL FIELD, THE QINTONG SAG, THE NORTHERN JIANGSU BASIN

俞凯 刘伟 陈祖华

Yu Kai Liu Wei Chen Zuhua

中国石油化工股份有限公司, 华东分公司, 南京, 210011

Southeastern Branch, SINOPEC, Nanjing, Jiangsu 210011, China

苏北盆地溱潼凹陷草舍油田泰州组油藏是一个复杂断块油藏,边界断层遮挡性较好,内部小断层则基本不封闭,储层连通性较好。室内实验注入CO2对泰州组地层原油起到了明显的膨胀降粘作用,满足CO2混相驱的要求。注气前泰州组油藏水驱井网存在开发层系划分较粗、层间矛盾严重、局部地区井网不完善、平面开采不均衡、纵向油层动用程度差异等问题,注入CO2后的动态监测表明,注气井吸气剖面得到明显改善,地层达到最小混相压力,原油重质组分被动用,整个区块产量稳定并初步见效。

The Taizhou Formation reservoir in the Caoshe Oil Field of the Qintong Sag of the Northern Jiangsu Basin is a complex fault block reservoir.Border faults work as good barrier while internal ones are unbounded,resulting in communication of reservoirs.Injection of CO2 in laboratory experiment obviously expands crude oil and reduces viscosity,hence is qualified for CO2 miscible flooding.Before gas injection,there are many problems with flooding pattern of the Taizhou Formation reservoir.For example,the division of development series is too simple;interlayer contradicts with each other;well pattern in some region is not perfect;plane productions are unbalanced;and vertical production degrees are different,et al.Dynamic monitoring after CO2 injection has proved that,gas entry profiles of gas injection well are improved;formation reaches the minimum miscibility pressure;heavy components in crude oils are produced;and production in the whole region is stable and advancing.

https://doi.org/10.11781/sysydz200802212