长庆油田同心双管数字式分注工艺技术研究

Study on the Concentric Double-tube Digital Separate Injection Technology in Changqing Oilfield

针对采出水回注井腐蚀结垢严重、分注难度大的问题,研发了同心双管地面数字式分注技术,攻克井下插管密封和带压作业等技术难题,形成封隔器双管分注与可钻桥塞双管分注两种模式。长庆油田目前推广两种同心双管技术,双管环空注上层,内管注下层,测试调配在地面进行,有效解决采出水分注井井筒易结垢及测试投捞成功率低的问题。同心双管地面数字式分注技术优化定型,实现了采出水回注井全天候自动测调达标任务。结合目前长庆油田油藏特征和水驱开发需求,建立了股份公司成熟试验区采油三厂吴x区,采油八厂元x区、采油一厂午x区,试验区总体水驱动用程度上升1%,自然递减下降1.9%,含水上升率下降0.3%。对油藏上缓解剖面矛盾、提高水驱动用程度、降低自然递减起到推动作用,打造全周期低成本分注工艺,助推油田开发效果不断提升。

In view of the serious corrosion and scaling,the difficulty of separate injection of produced water reinjection well,the concentric double pipe ground digital separate injection technology was developed to overcome the technical problems of intubation sealing and pressure operation,forming two modes of packer double pipe separate injection and drillable bridge plug double pipe separate injection.Two kinds of concentric double pipe technology are popularized in Changqing oilfield now,double pipe annulus is used to inject upper layer,inner pipe is used to inject lower layer,testing and deployment are carried out on the ground,which effectively solves the problems of frequent scaling of produced water injection well bore and low test fishing success rate.The optimization and finalization of the concentric double pipe surface digital separate injection technology has realized the all-weather standard task of automatic measurement and adjustment of produced water reinjection wells.According to the reservoir characteristics and water drive development demand of Changqing oilfield,mature test areas including No.3 oil production factory Wu X area,No.8 oil production factory Yuan X area and No.1 oil production factory Wu X area were established.The overall water drive production degree in the test area was increased by 1%,natural decline was by decreased 1.9%,and water cut rise rate was decreased by 0.3%,which played a driving role in alleviating the profile contradiction,improving the water drive production degree and reducing the natural decline in the reservoir,creating a full cycle low-cost separate injection process,and promoting the continuous improvement of the oilfield development effect.