盐穴储气库建腔期浓度场分布规律研究

以盐岩能源地下储库群建造工程为背景,用相似理论中的量纲分析法建立了建腔期腔内浓度场相似模型实验平台,对盐岩建腔期腔体内浓度场分布规律进行了系统分析,研究发现:建腔期腔体内卤水浓度在同一水平面上除边界层外是均匀分布的,边界层浓度高于同一水平面上其他位置;在竖直方向上,注水流量、套管位置、循环方式都会影响卤水浓度的分布;反循环造腔时,卤水浓度在竖直方向上呈现梯度分布,且随深度增加而增加,而且在竖直方向上的分布的浓度梯度受到造腔工艺的影响。在反循环建腔时,根据腔体卤水浓度在纵向上的分布特征,可以将其分为4个区域,饱和沉淀区,缓冲扩散区,对流扩散区和自由扩散区。获得了反循环建腔时卤水浓度分布函数,分析了造腔工艺相关参数对卤水浓度分布的影响规律,为盐穴储气库建腔提供指导意义。

Study on the Concentration Field Distribution in

To analysis the concentration distribution and the concentration field variation in cavity, taking the underground energy storage of salt rock as a demonstration project, a similar model experimental platform of concentration filed in construction period of salt caverns is established based on the similar theory of “selected laws of physics”. The study shows that: the brine concentration in the same horizontal plane is uniformly distributed beyond the boundary layer where has a higher concentration than other locations. The brine concentration is affected by water injection flow, casing position and circulation mode. In the reverse circulation method, the brine concentration has a continuous gradient distribution of increases with depth which affected by washing techniques. According to the distribution characteristic in the vertical direction, in the reverse circulation method, concentration field can be divided into four regions: the saturation precipitation zone; buffer diffusion zone; convection diffusion zone and free diffusion zone. Function of brine concentration distribution is obtained, and the influence on brine concentration distribution caused by related parameters of washing techniques has been made, which can provide guidance for the construction of salt cavern.