盐穴压缩空气储能腔体稳定性数值模拟

Numerical Simulation Study on the Stability of Compressed Air Energy Storage Cavity

与地下盐穴储气库相比,盐穴压缩空气储能库注采气频率高,单日压降幅度大,对地下盐穴的安全稳定性带来了挑战。为了研究盐穴在长期储能发电过程中的腔体稳定性,论证压缩空气储能电站在国内建设的可行性,以江苏某地区盐矿900~1 100 m深盐层为研究对象,采用FLAC3D软件建立压缩储能腔体模型,对腔体长期注采气工况下的稳定性进行数值模拟,分析了体积收缩、相邻腔体安全矿柱宽度、储气压力对腔体使用效率影响等问题。研究结果表明:夹层附近易出现拉伸破坏,储库在30年满负荷运行过程中体积收缩率仅3%左右,国内盐矿具备建设压缩空气储能库具的可行性;进行腔群设计时,相邻井距与腔体有效半径之比d≥1.84;设计运行高压值越接近储气最高压力、生产压差越大越利于提高腔体使用效率。

Compared with the underground salt cavern gas storage,the frequency of injection and production gas of the salt acupoint compressed air storage reservoir is high and the single day pressure drop is large,which brings challenges to the safety and stability of the underground salt caverns.In order to study the stability of the cavities in the process of long-term energy storage,and the feasibility of the compressed air energy storage power station in China is demonstrated.The 900 ~ 1 100 m depth of the salt mine in a certain area of Jiangsu is taken as the research object.The Flac3 D software is used to establish the compressed energy storage cavity model,and the stability of the cavity under the condition of the cavity for long-term injection and production gas was calculated.The effects of volume shrinkage,safety pillar width and pressure on the efficiency of chamber were analyzed.The results show that the tensile failure is easy to occur near the interlayer,and the volume shrinkage rate of the reservoir is only about 3%during the full load operation of the 30 year.The domestic salt mine has the feasibility to build the compressed air storage tank.When the cavity group is designed,the ratio of the adjacent well spacing to the effective radius of the cavity is more than 1.84;the high pressure value of the design and operation is closer to the gas storage,and the bigger difference between highest pressure and production pressure is more conducive to improving the efficiency of the cavity.