基于腔体稳定性的盐岩储气库注采方案优化研究

Optimization of injection and production scheme of salt gas storage based on cavity stability

周军 胡承强 彭井宏 梁光川 黄薪宇 马俊杰 王涛

西南石油大学石油与天然气工程学院，四川 成都 610500 中国石油西南油气田公司安全环保与技术监督研究院，四川 成都 610500

Petroleum Engineering School, Southwest Petroleum University, Chengdu 610500, China Safety, Environmental Protection and Technology Supervision Institute, Southwest Oil and Gas Field Company, PetroChina, Chengdu 610500, China

在盐岩储气库运行过程中，注采方案对于整个腔体的稳定性具有很大的影响。若采用不合理的注采方案，腔体围岩会发生拉张、膨胀损伤，长此以往会导致腔体收缩率增加，库容减小，甚至使整个储气库失效。为保障储气库的运行稳定性，文中建立了以腔体总温升最小为目标的注气优化模型和以腔体总压降最小为目标的采气优化模型。模型以单井日注/采气量作为决策变量，并涉及日注/采气总量、腔体最高/最低运行压力及单井注/采气能力等约束条件，将所建立的优化模型应用于某埋藏深度为1 000 m的盐岩储气库，并采用通用数学建模系统GAMS进行求解。优化结果表明，优化注气方案比均匀注气方案的腔体总温升低2.84 K，降低了31.6%；优化采气方案比均匀采气方案的腔体总压降低0.553 MPa，降低了12.7%。由此可以看出，优化注采方案有效地控制了运行过程中腔体的温度和压力变化程度，进一步提高了盐岩储气库的运行稳定性。

During the operation of salt gas storage, the injection and production scheme has a great influence on the stability of the whole cavity. If an unreasonable injection and production scheme is adopted, the surrounding rock of the cavity will be damaged by tension and expansion, which in the long run will lead to the increase of the shrinkage rate of the cavity, the reduction of the storage capacity, and even the failure of the whole gas storage. In order to ensure the operational stability of the gas storage, the optimization model of gas injection with the goal of minimizing the total temperature rise of the cavity and the optimization model of gas recovery with the goal of minimizing the total pressure drop of the cavity are established. The model takes the daily gas injection and production volume of a single well as the decision variable, and involves the constraints such as the total daily gas injection and production volume, the maximum and minimum operating pressure of the cavity and the gas injection and production capacity of a single well. The optimized model is applied to a salt gas storage with a burial depth of 1,000 m, and the general mathematical modeling system GAMS is used to solve the problem. The optimization results show that the total cavity temperature rise of the optimized gas injection scheme is 2.84 K lower than that of the uniform gas injection scheme, which is reduced by 31.6 %. Compared with the uniform gas recovery scheme, the total cavity pressure of the optimized gas recovery scheme is reduced by 0.553 MPa and 12.7%. It can be seen that the optimized injection and production scheme can effectively control the temperature and pressure variation of the cavity during operation, and further improve the operational stability of salt gas storage.

10.6056/dkyqt202301023