将二氧化碳注入到深部咸水层中,形成复杂的多组分、多相流系统。二氧化碳在压力梯度、浓度差作用下不断扩散,逐步带走盐溶液中的水分,导致各组分的相态变化,盐结晶析出,阻塞了咸水层孔隙通道,从而降低了二氧化碳的注入效率,研究该干化效应的影响因素并为工程选址提供依据具有重要意义。采用二维径向模型建立多相流体的流动方程,并结合相对渗透率和毛细压力方程探讨二氧化碳注入速率、咸水层含盐量、毛细压力的特征参数对干化效应的影响,干化效应可用固体饱和度值进行定量描述。结果表明:二氧化碳运移分3个区域:干涸区、气液相混合区及液相咸水区,干化效应主要发生在井周的干涸区。在毛细作用下固体饱和度随注入速率的减小而增大,随咸水层含盐量增大而增大,随毛细作用增大而增大。因此,提高二氧化碳的注入速率,向咸水层中注水稀释含盐量或选择粒径较大的均质咸水层减小毛细作用,均可降低盐结晶对孔隙通道的阻塞,提高注入效率。 Carbon dioxide is injected into deep saline formations to form complex multi-component, multi-phase flow systems. Under the action of pressure gradient and concentration difference, carbon dioxide diffuses continuously and gradually removes the water from the salt solution, resulting in the phase change of the components. The salt crystallizes out and blocks the pore channel of the saline aquifer, thus reducing the carbon dioxide injection efficiency, Studying the influencing factors of this drying effect and providing the basis for the project site selection is of great significance. The two-dimensional radial model was used to establish the flow equation of multi-phase fluid. The effects of carbon dioxide injection rate, salt water content and capillary pressure on the drying effect were discussed based on relative permeability and capillary pressure equation. Quantitative description of solid saturation values ​​available. The results show that the carbon dioxide transport is divided into three areas: dry area, gas-liquid mixing area and liquid saline area, and the drying effect mainly occurs in the dry area of ​​the well. Under capillary action, the saturation of solid increases with the decrease of injection rate, increases with the increase of salinity in saline aquifer, and increases with the increase of capillary action. Therefore, increasing the injection rate of carbon dioxide, diluting the salt content in the saline water layer or reducing the capillary effect by selecting a homogeneous saline aquifer with a larger particle size can reduce the blockage of the salt channel on the pore channel and improve the injection efficiency.