薄层状盐岩地下储气库工程地质条件及可行性分析

摘要

The safety of underground salt cavity gas storage is the key geological problem of gas storage operation. The Pingdingshan salt field is characterized with thin layers,multiple interlayers and deeply buried layers.Its geological storage feasibility and ground settlement are studied using the permeability,rheology and stability of layered salt rock.First,the pure salt rock,layered salt rock and mudstone interlayer samples are collected.Then electronic microscope scanning and triaxial compression creep experiments are conducted.Then the salt rock cavities are detected by CYT method.Field monitoring shows that ground settlement is small and fluctuating because some influence zones of mining wells are overlapped.Based on the geological characteristics of study area,it can be concluded that the geological conditions of Pingdingshan underground salt cavity gas storage are favorable,and also can provide some references for similar projects in China.%地下盐穴储气库安全性是蓄气运行的关键地质问题。针对平顶山盐田盐层薄、夹层多以及埋藏深等特征，从薄层状盐岩的渗透性、流变性以及稳定性3个方面，详细讨论了储气库的地质可储性及地面沉降问题。首先采集了纯盐岩、互层状盐岩、泥岩夹层3种岩石试样，分别进行了电镜扫描和不同应力水平下的三轴压缩蠕变试验，并应用 CYT 法对试验区进行了深部盐岩溶腔的探测。鉴于试验区多个采井影响区的重叠，地面沉降量实际监测结果比较复杂，绝对值偏小但具有波动性。综合上述地质特征，作出了平顶山地下盐穴储气库地质条件良好的结论，为我国同类工程提供一定的实际参考。