盐穴能源储库氮气阻溶造腔气垫控制理论研究  

Control theory of gas blanket in energy storage salt cavern construction with nitrogen dissolution inhibition

作　　者：刘伟[1] 李德鹏 高丽[2] 万继方 李林[1] 唐海军[2] 徐贵春[2] 姜德义 LIU Wei;LI De-peng;GAO Li;WAN Ji-fang;LI Lin;TANG Hai-jun;XU Gui-chun;JIANG De-yi(State Key Laboratory of Coal Mine Disaster Dynamics and Control,Chongqing University,Chongqing 400044,China;SINOPEC Jiangsu Oilfield Branch Petroleum Engineering Technology Research Institute,Yangzhou,Jiangsu 225009,China;CNPC Engineering Technology R&D Company Limited,Beijing 102206,China)

机构地区：[1]重庆大学煤矿灾害动力学与控制国家重点实验室,重庆400044 [2]中国石油化工股份有限公司江苏油田分公司石油工程技术研究院,江苏扬州225009 [3]中国石油集团工程技术研究院有限责任公司,北京102206

出　　处：《岩土力学》2023年第8期2205-2220,共16页Rock and Soil Mechanics

基　　金：国家自然科学基金(No.52074046,No.51804003);重庆英才计划“包干制”项目(No.cstc2022ycjh-bgzxm0035)。

摘　　要：盐穴具有良好的稳定性和密闭性,是储存天然气、石油、氢气等的理想场所。传统水溶造腔采用的油垫阻溶存在阻溶效果差、卤水油污重等问题,无法满足绿色矿山建设要求。气垫作为一种替代品备受关注,但因其起步较晚、控制难度大,加之我国复杂的盐层地质条件,阻碍着其推广应用。为此,首先分析了不同造腔阶段气垫控制特点,然后在对气-液界面处压力平衡分析的基础上提出了不同阶段气垫厚度预测及注气量计算方法,结合某井建槽期实例给出了建议气垫厚度及其波动范围,探明了气垫厚度和注气量随造腔推进的变化规律,最后探讨了气垫阻溶应用相关的关键问题。研究结果表明:建槽期及收顶期以气垫厚度控制为主,建腔期及腔体修复阶段则以气-液界面位置控制为主。建议建槽期平均气垫厚度不低于0.3 m,建槽期初期气垫厚度波动迅速,应设置较大的气垫厚度并及时补注氮气,随后气垫厚度波动趋于稳定,补气时间间隔可逐渐拉长。随造腔时间增加,单次补气量越来越大,累计补气量整体呈线性增长。造腔过程中井口气压及气-液界面处气垫压力先增加后线性减小,应实时监测井口气压变化。气垫阻溶与油垫阻溶成本相近但环境效益显著,可重复利用排出氮气及井口注气设施以节约成本。现场应加强气-液界面位置监测,可采取光纤监测和中子测井相结合的方式实时准确监测界面位置信息。Salt caverns have good stability and air-tightness,and thus are ideal places for storage of natural gas,oil,hydrogen,etc.The oil blanket used in the conventional salt caverns created by solution mining has problems such as poor dissolution inhibition effect and heavy oil contamination,which cannot meet the requirements of green mine construction.As a substitute,gas blanket has attracted much attention.However,its application is hindered due to great difficulty in control,and the complex geological conditions of salt rock strata in China.To this end,the characteristics of gas blanket control at different cavern construction stages were analyzed first,and then the methods for predicting the thickness of gas blanket and calculating the gas injection amount at different stages were proposed based on the analysis of the pressure balance at the gas-liquid interface.Combined with an example of a well in the groove construction period,the recommended thickness of gas blanket and its fluctuation range were given,and the variation law of the gas blanket thickness and the gas injection amount with the cavern construction progress was proved.Finally,the key problems related to the application of gas blanket were discussed.The results showed that the gas blanket thickness is mainly controlled during the groove construction and roof formation periods,and the gas-liquid interface position is mainly controlled during the cavern construction and cavern repair periods.It is suggested that the average gas blanket thickness during the groove construction period should not be less than 0.3 m.The thickness of gas blanket fluctuates rapidly at the beginning of the groove construction period,and thus a larger gas blanket thickness should be set up and the nitrogen should be replenished in time.Then the gas blanket thickness tends to be stable,and the gas replenishment interval can be gradually extended.With the increase of cavern construction time,the single gas replenishment volume becomes larger and larger,and the cumulative gas reple

关 键 词：盐穴储库 氮气阻溶 压力平衡 气垫设计 气-液界面 

分 类 号：TU457[建筑科学—岩土工程]