Abstract: Rock salt formations are characterized by wide distribution, excellent sealing properties, and self-healing capabilities, which provide ideal storages for energy resources such as oil, natural gas, hydrogen, helium, compressed air, and CO₂. However, the significant burial depth of salt formations, the complex operating conditions of energy storage caverns, and the pronounced multifield coupling effects during surrounding rock failure pose considerable challenges in accurately predicting and controlling the operational safety of salt cavern storage facilities. To investigate the evolution of stability and sealing performance of salt cavern energy storage under complex conditions, a largescale geomechanical physical simulation apparatus was developed. The device consists of main experimental device, confining pressure loading unit, axial compression loading unit, rapid loading unit, data acquisition and control system, and other auxiliary function modules. The test device operates at the confining pressure up to 70 MPa, temperatures from 20 to 95 ℃, and gas pressures from 0 to 30 MPa. It can simulate the in -situ temperature, stress and seepage conditions of the salt cavern at a depth of 3 000 meters. The maximum sizes of the samples used for the device are Φ200 mm×400 mm (diameter and height). A cavity reduced in size can be created within the sample to simulate the accrual cavern. The independent gas-liquid supply module can provide a variety of gaseous media, including air, natural gas, hydrogen, helium and carbon dioxide, as well as liquid media such as oil and brine. It can afford the simulation of different types of media stored in the salt cavern. The temperature, axial compression, and confining pressure can be controlled independently, which can afford the complex loading and unloading experimental conditions. The device was used to conduct permeability tests on rock salt samples. Its testing accuracy can reach 10^-23m².The damage tests of the samples within cavities are carried out, and the effects of the cavity shape, cavity location, and gas/liquid injection-production conditions are included. The acoustic emission signals during the sample failure process are monitored, which can real-time reflect the damage and failure of the rocks around the cavity. This experimental device provides a critical platform for understanding the failure and damage mechanisms, as well as for optimizing the design and operational parameters of salt caverns used for energy storages.

Key words: salt cavern energy storage, physical simulation experiment, device development, permeability testing, surrounding rock stability

摘要： 盐岩地层具有分布范围广、密封性好及损伤自修复等特点,是储存石油、天然气、氢气、氦气、压缩空气和CO₂等能源或能源物质的理想场所。但由于盐岩地层埋深大、储能库运行工况复杂、围岩破坏多场耦合效应显著,导致准确预测和调控盐穴储库运行安全充满挑战。为了揭示复杂工况下盐穴储能库的稳定性与密封性能演化规律,自主研发了大型盐穴储能库地质力学物理模拟实验装置。该装置包括主体实验装置模块、围压加载动力装置模块、轴压加载动力装置模块、快速加载动力装置模块、数据采集及控 制系统模块和辅助功能模块等。试验装置的最大围压为70 MPa、温控范围为20~95 ℃、最大气体压力为30 MPa,可准确模拟深度为3 000 m位置处的盐穴储能库原位温度 、应力和渗流条件,适用试样尺寸达到Φ200 mm×400 mm(直径和高度),可在岩心试样内部水溶建造一个腔体,实现对盐穴储库的物理模拟。独立的气液供给模块,可提供空气、天然气、氢气、氦气和二氧化碳等气体以及石油、卤水等液体介质,实现对利用盐穴存储不同类型介质的模拟。该实验装置具有独立的温度、轴压和围压控制系统,能实现复杂温压交变荷载的加/卸载控制。利用该装置开展了盐岩渗透性测试试验,测试精度达10^-23m²。围岩响应试验可对不同的腔体形态、腔体位置和注采条件等进行模拟,并能够采集试样破坏过程中的声发射信号,实时监测围岩的损伤破坏。该实验装置可为揭示盐穴储能库失效破坏机理以及优化储能库形态和运行参数提供重要的实验测试平台。

关键词: 盐穴储能库, 物理模拟实验, 装置研制, 渗透性测试, 围岩安全