地下水封石油洞库水封准则研究

Water sealing criteria for underground oil storage in unlined rock caverns

水封准则是地下水封石油洞库设计与运行管理的基础。为获取工程应用更加简便实用的地下水封石油洞库水封准则,基于裂隙水流动阻力效应的研究,建立了气压推动裂隙水迁移的油汽逃逸模型;根据裂隙水迁移启动的临界条件,推导了铅直裂隙和倾斜裂隙中裂隙水满足油汽封存的临界水封厚度计算公式,讨论了临界水封厚度条件下洞库的原油水封效果。利用气液两相流数值分析成果和工程实际监测成果,论证了提出基于临界水封厚度的地下水封石油洞库水封准则的正确性。

The water sealing criterion is a base for the design and operational management of underground rock caverns for oil storage. To obtain a simple and practical criterion to evaluate the water sealing effect of unlined underground rock caverns for oil storage, a gas escaping model is established for describing the migration of fracture water owing to high gas pressure based on the researches on resistance force acting on the fracture water. According to the critical conditions of fracture water movement, a formula for calculating the critical water sealing height satisfying the gas sealing condition is deduced. Furthermore, the water sealing effect of oil and gas in the unlined rock caverns under the critical water sealing height is discussed. The validation of the suggested water sealing criterion is proved by the results of two-phase flow numerical analysis and in-situ measured data.