注采交变下火山岩储气库储层力学稳定性试验研究  

Experimental study on mechanical stability of volcanic underground gas storage under cyclic injection and production

作　　者：王滨涛 韩琳 于继崇 图亚 刘仁地 温曹轩 赵小青 贾善坡 WANG Bintao;HAN Lin;YU Jichong;TU Ya;LIU Rendi;WEN Caoxuan;ZHAO Xiaoqing;JIA Shanpo(Daqing Branch,CNLC,Daqing 163412,Heilongjiang;School of Earth Sciences,Northeast Petroleum University,Daqing 163318,Heilongjiang)

机构地区：[1]中国石油集团测井有限公司大庆分公司,黑龙江大庆163412 [2]东北石油大学地球科学学院,黑龙江大庆163318

出　　处：《长江大学学报(自然科学版)》2025年第1期55-65,共11页Journal of Yangtze University(Natural Science Edition)

基　　金：国家自然科学基金面上项目“气藏型储气库泥岩盖层的疲劳效应及密封性动态演化机理研究”(42072166);黑龙江省自然科学基金项目“地下储库泥岩盖层损伤及其渗透性演化机制研究”(LH2020D004)。

摘　　要：储层在注采交变下的力学稳定性是储气库注采安全运行和提压扩容的重要支撑。以X火山岩储气库为例,结合设计注采运行上下限压力,计算了储层有效应力随地层压力变化规律,进一步设计了24块储层样品三轴交变应力试验方案。试验结果表明,在设计注采运行上下限压力和储气库寿命下,储层力学稳定性良好,但有3块样品在加载至安全上限的过程中发生破坏,破坏特征与常规三轴样品存在差异,主要体现在交变应力试验样品破坏后裂缝长度短、数量多;未发生破坏的样品动态弹性模量整体随交变次数增加,但增加幅度受围压的影响,发生破坏的样品受裂缝的影响,动态弹性模量均有不同程度降低。根据基于塑性应变的损伤计算结果,建立了能反映储层疲劳破坏的三阶段规律的损伤-交变次数经验公式,通过实验数据拟合验证了经验公式的适用性与合理性(相关系数R^(2)均大于0.99),并进一步预测了3块样品的剩余寿命,可为后期提压扩容和其他相似工程储层稳定性研究提供参考。The mechanical stability of the reservoir under the cyclic injection and production is an important support for the safe operation of the injection and production of the gas storage and for increasing pressure and expanding capacity.Taking X volcanic gas storage as an example,combined with the designed upper and lower limit pressure of injection and production operation,the effective stress of reservoir changes with formation pressure were calculated,and the triaxial alternating stress test scheme of 24 reservoir samples was further designed.The results show that,under the designed upper and lower limits of injection-production operation and the limiting of gas storage service life,the mechanical stability of reservoir is positive,but three samples fail in the process of loading to the safe upper limit.The failure characteristics are different from those of conventional triaxial samples,which are mainly reflected in the short length and large number of fractures after the failure of alternating stress test samples.The dynamic elastic modulus of the samples without failure increases with the number of alternating times,but the increasing range is affected by confining pressure.The dynamic elastic modulus of the samples with failure is reduced to varying degrees due to the influence of cracks.According to the damage calculation results based on plastic strain,the empirical formula of damage versus number of cycles reflecting the three-stage law of reservoir fatigue failure was established.The applicability and rationality of the empirical formula were verified by experimental data fitting(correlation coefficient R^(2)were all greater than 0.99),and the remaining fatigue life of the three samples was further predicted,which can provide a reference for the reservoir stability research of later pressure increasement and capacity expansion and other similar projects.

关 键 词：火山岩 储气库 储层 交变应力 稳定性 

分 类 号：TE88[石油与天然气工程—油气储运工程]