双6储气库运行综合评价及扩容潜力研究

辽河油田双6储气库自2014年投入运行以来,已经历了“六注四采”的平稳高效运行,2018年在中国石油各大储气库中率先实现达容扩容,第6注气期末库存量达53.27×10⁸m³,达容率为129%。针对储气库未来扩容方向不明晰的问题,从气藏的地质特征和开发动态分析出发,综合运用动、静态资料和观察井监测数据,结合数值模拟技术,分析研究储气库的注采状况、压力变化、气液界面变化、圈闭密封性等情况,并在此基础上进行扩容调峰的潜力评价。研究结果表明,储气库的注采能力逐年趋好,采用的直井-水平井组合井网极大提高了运行效率,在反复注采过程中,原油的采出和边水外推是储气库扩容的主要原因。在生产动态分析的基础上,结合区块地质特征,新增部署15口注采井,预计新井实施后,库容的控制程度可提高至95%以上。研究成果为现场生产管理及扩容调峰提供了依据,对同类型储气库建设具有一定指导意义。

Comprehensive Evaluation on Operation and Research on Capacity Expansion Potential of Shuang 6 Gas Storage

Since put into operation in 2014, the Shuang 6 gas storage in Liaohe Oilfield has experienced smooth and efficient operation of "six injections and four productions". In 2018, the Shuang 6 gas storage took the lead in achieving capacity summit and expansion among CNPC's major gas storages, and at the end of the sixth gas injection period, the inventory reached 53.27×10⁸m³, with capacity reaching rate of 129%. In view of the unclear direction of the future expansion of the gas storage, starting from the geological characteristics and dynamic production analysis of the gas reservoir, comprehensively using the dynamic and static data as well as the monitoring data from observation wells, combined with numerical simulation technology, the injection-production status, pressure changes, gas-liquid interface changes, and trap sealing performance of the gas reservoir were studied, and on this basis, the potential for capacity expansion and peak shaving was evaluated. The research results show that the injection-production capacity of gas storage is getting better year by year, and the adopted vertical-horizontal well pattern has greatly improved the operation efficiency. During the process of repeated injection and production, the production of crude oil and migration of edge water are the main reasons for capacity expansion of the gas reservoir. Based on the dynamic production analysis, combined with geological characteristics of the block, 15 injection and production wells would be newly deployed. It was expected that after the implementation of the new wells, the control degree of the storage capacity could be increased to more than 95%.The research results provide a basis for on-site production management as well as capacity expansion and peak shaving, which has certain guiding significance for the construction of the same gas storages.