淮安盐穴储气库注采循环运行压力限值确定

Determination of operating pressure limit for injection-production cycle of salt-cavern gas storage in Huai’an City

基于淮安库区盐岩的物理力学参数实验结果,结合现场地层资料和储气库设计形状资料,首先采用压力梯度原则和相关技术规程,确定内压上下限的初值,然后利用FLAC3D软件进行恒压流变分析,仿真模拟了盐腔注采循环内压变化的全过程。通过分析盐腔最大主应力和腔体体积收缩率模拟规律,综合考虑模拟计算结果和国外相关经验,建议淮安库区典型井的注采循环内压取12～26MPa。研究成果可为该储气库的运行及复杂地下大埋深盐穴储气库长期稳定性的评价提供参考。

Based on experimental results of physical mechanical parameters for rock salt of storage area in Huai＇an City, Jangsu Province, stratigraphic information and design shape information of gas storage, pressure gradient principle and relevant technical regulations are used to determine initial value of the upper and lower limits for internal pressure. Then FLAC 3D software is used to conduct constant pressure rheologieal analysis and analogue simulation for overall process of internal pressure change in the salt-cavern injection-production cycle. By analyzing the simulation law of maximum principal stress and volume shrinkage in the salt-cavum and comprehensively considering analog computation results and relevant foreign experience, it is suggested that taking 12 MPa to 26 MPa internal pressure for injection-production cycle of the typical well in Huai＇an storage area is available. The research results will provide a certain reference to the gas storage operation and assessment in long-term stability of complex underground large buried depth salt-cavern gas storage.