潜江凹陷王58井区盐穴地下储气库潜力分析

Potential Analysis of Underground Gas Storage in Salt Cave in Wang58 Well Area of Qianjiang Depression

建立地下储气库已经成为保障能源安全的主要手段,为了研究潜江凹陷地下储气库,分别从地质特征、盐层特征、建库层段等方面进行了系统分析。研究结果显示:王58井区盐矿源丰富,潜二段具有盐层厚度大、夹层厚度薄、含矿率高的特点;通过开展王4-2井盐岩溶解实验及王储3井夹层垮塌实验,优选出潜二段第10~16韵律层为建腔目的层;开展了正常循环注采气条件下的模拟计算,优选出单腔直径为85 m近似梨形的腔体形态;建立了两个相邻溶腔三维地质力学模型,优选出三角形井网300 m井距布井方式。预计王58井区可部署40个盐腔,总库容量为48.09×10^8m^3,有效工作气量为28.04×10^8m^3。

The establishment of underground gas storage has become the main means to ensure energy security.In order to study the prospect of underground gas storage in Qianjiang Sag,systematic analysis is carried out from geological characteristics,salt layer characteristics and reservoir formation.Wang58 well area is rich in salt mineral resources,and the second member of Qianjiang formation is characterized by large salt layer thickness,thin interbedded rock layer thickness and high ore bearing rate.Through the salt rock dissolution experiment of Wang 4-2 well and the collapse experiment of Wang Storage 3 well,the 10th-16th rhythmic layer of the second member of Qianjiang Formation is preferred as the target layer for cavity construction.Through the simulation calculation under the condition of normal circulation injection gas,an approximate pear-shaped cavity shape with a single cavity diameter of 85 m is preferred.A three-dimensional geomechanical model of two adjacent cavities is established,and the 300 m well spacing of the triangular well pattern is selected.It is estimated that 40 salt chambers can be deployed in Wang 58 well area,with a total storage capacity of 4.809 billion square meters and an effective working volume of 2.804 billion square meters.