盐穴储气库运行压力对腔体稳定性的影响

Stability analysis of different shaped salt caverns under operation pressure

时文 申瑞臣 徐义 苏海洋 杨长来

SHI Wen SHEN Ruichen XU Yi SU Haiyang YANG Changlai

中国石油勘探开发研究院，北京　100083 中国石油集团钻井工程技术研究院，北京　100195 中国石化川气东送管道分公司，湖北武汉　430205

Research Institute of Petroleum Exploration and Development, PetroChina, Beijing 100083, China CNPC Drilling Research Institute, Beijing 100195, China Sinopec Sichuan-East Natural Gas Transmission Project Branch, Wuhan 430205, China

为考察盐穴储气库长期运行的稳定性，对 3种不同形态的盐穴储气库模型在变化的运行压力下从腔壁应力分布及溶腔体积变化两方面进行分析。研究表明：盐穴腔体投入运行的初期是腔壁应力水平最高的时期，应力集中主要出现在腔壁曲率较大的部分；在变化的内压之下，应力松弛现象同样明显，腔壁应力在逐渐降低的同时，各部位的应力水平趋于均匀；在 4~14.5 MPa的运行压力下，溶腔应力变化及体积变化未随运行压力变化出现明显波动；模拟 10年的运行之后，梨形、近似球形和圆锥形储气库的体积将分别缩小 27%、22%和 37%，体积缩减速度在不断趋于平缓。

In order to investigate the stability of salt caverns in long term operation, three different shapes of salt cavern models were analyzed with respect to the stress distribution of cavern wall and volume change of cavern under various running pressures. The simulation results showed that stress on the wall is at the highest level in the initial operation period of the cavern storage, and stress concentration occurs mainly in parts with higher curvature on the cavity wall. The stress relaxation is also noticeable under fluctuating operation pressure, and the stress in different parts becomes evenly distribution along the cavern wall with stress gradually declining. There is no obvious fluctuation in changing of cavern stress and cavern volume when the operation pressure varies from 4 to 14.5 MPa annually. After a time span of ten years simulation, volumes of pear-shaped cavern, ellipsoid-shaped cavern and cone-shaped cavern reduces 27%, 22% and 37% respectively, and the decrease rate of cavern volume becomes smaller and smaller.