储层条件下龙马溪组全直径页岩吸附实验

Isothermal adsorption experiment of full-diameter shale core in Longmaxi Formation
under reservoir condition

 赵春鹏 2 伦增珉 2 王卫红 2 刘华 2 王海涛 2

中国石化石油勘探开发研究院，北京 100083 中国石化页岩油气勘探开发重点实验室，北京 100083）

Exploration and Production Research Institute, SINOPEC, Beijing 100083, China Key Laboratory of Shale Oil and Gas Exploration and Development, SINOPEC, Beijing 100083, China)

 为了更加真实地反映储层条件下页岩的吸附特征，采用容量法原理建立了全直径页岩吸附实验流程，并在储层条件下开展了涪陵龙马溪组全直径页岩等温吸附实验。实验最高平衡压力达到原始储层压力。通过引入吸附相密度建立了三参数吸附模型，采用该模型对实验数据进行拟合，并获得了吸附特征参数，进而得到了吸附相体积及实际自由空间体积随压力的变化特征。研究认为，吸附实验曲线在高压下出现“下掉”现象，是由于计算吸附量时未考虑吸附相对自由空间体积的影响。现有煤页岩标准不能很好地应用于全直径页岩吸附平衡判断，建议尽快建立针对块状/全直径页岩吸附平衡的实验判定标准或规范。

 In order to study more realistic adsorption characteristics of shale reservoir, full-diameter shale adsorption experiment process is established and isothermal adsorption experiment is carried out under the reservoir condition. Full-diameter core in Longmaxi Formation is used and the maximal pressure reaches as high as primary reservoir pressure. The experimental results show that the adsorption curve declines under high pressure. By introducing the adsorption phase, adsorption model of three parameters is established to fit experimental data and adsorption characteristic parameters are obtained. On this basis, the adsorbed phase volume and the actual volume of free space with pressure are obtained, and we believe that the phenomenon of curve declining under high pressure is because of not considering the influence of the free space as calculating adsorption quantity. In addition we suggest that experiment standard or specification about block or full-diameter shale adsorption equilibrium should be set up as soon as possible.

10.6056/dkyqt201606013