中低渗透边水油藏高含水阶段综合治理对策

Comprehensive treatment countermeasures for middle-low permeability edge water reservoirs at high water cut stage

SJW油区为带边水的中低渗构造-岩性油藏,边水能量弱,区块油水井均压裂投产投注,目前含水率高,关停井多,采出程度低。本文采用油藏精细描述技术,搞清了砂体展布规律,分析了影响水驱效果的主控因素,目前主力延9油层的井网受效一般,顺河道方向砂体连通性好,为注采主流通道。经过生产动态分析、开发效果评价及开发技术对策论证,提出了3点开发调整策略:采用点状不规则注采井网,增加注水井数,温和注水,恢复地层压力;在油层下部注水泥,形成一定范围的水泥封堵层段,封堵下部压裂缝,同时降低单井注水量,防止油层底部水淹;使用油井转注、换层补孔、控液复产、堵水调剖、提液等油水井综合治理措施。

The SJW oil block is a low-permeability structural-lithologic reservoir with weak edge water.The oil and water wells are both put into production or injection after hydraulic fracturing.At present,the water cut is high.Many wells are closed,and the recovery degree is low.In this paper,the fine reservoir description technology is used to clarify the sand body distribution laws and analyze the main controlling factors that affect the water flooding effect.The current water injection effect of Yan 9 oil layer is not good,and the sand body has good connectivity along the river channel,which is main flow channel during injection and production.Additionally,production dynamic analysis,development effect evaluation and development technology countermeasure demonstration were carried out,and three development adjustment strategies were put forward,(1)adopting point-shaped irregular injection-production well pattern and increasing the number of water injection wells,restore formation pressure by gentle water injection.(2)Cement is injected into the lower part of the oil layer to form a certain range of cement plugging intervals to seal the fractures,meanwhile reducing the water injection rate to prevent water flooding at the lower part of oil layer.(3)Comprehensive treatment measures for oil and water wells are used such as production-to-injection,layer replacement and perforation adding,liquid control and re-production,water plugging and profile control,and fluid enhanced.