层状盐岩储气库造腔管柱弯曲原因分析及预防处理措施

Cause Analysis and Preventive Treatment Measures for String Bending During Cavern Creation in Layered Salt Rock UGS Facilities

在层状盐岩储气库的造腔过程中,由于各层不溶物含量不同,存在溶解速度上的差异,上下部盐岩溶漓后的泥岩夹层极易发生垮塌,造成造腔管柱弯曲。对比造腔井作业时的管柱弯曲情况与测腔前后泥岩夹层垮塌形态变化,说明泥岩夹层垮塌是造成造腔管柱弯曲的主要因素;针对控制泥岩夹层垮塌的造腔工艺及管柱弯曲的解卡措施,经现场应用取得一定效果,对层状盐岩储气库安全、高效建设具有借鉴意义。

During the cavern creation process in layered salt rock converted UGS(Underground Gas Storage)facilities,the difference in insoluble content among layers leads to variable dissolution rates,which makes the mudstone interlayers,after the dissolution of the upper and lower salt rocks,highly prone to collapse,causing bending of the cavern-created string.By comparing the string bending during cavern creation operations with the morphological changes of the mudstone interlayers before and after cavity measurement,the collapse of the mudstone interlayers is identified as the main factor causing the string bending.This paper proposes cavern creation techniques to control the collapse of the mudstone interlayers and measures to unstick bent string,which have achieved certain effects in practice and are of certain reference significance for the safe and efficient construction of layered salt rock UGS facilities.