CO_(2)-水-岩地化反应对致密砂砾岩物性、可动用性和微观孔隙结构影响

Effect of CO_(2)-brine-rock reaction on physical properties,mobility and microscopic pore structure of tight conglomerate

通过CO_(2)-水-岩反应实验,探究反应对于储层润湿性、微观孔隙结构、可动流体饱和度、气驱效果等4个方面的影响。结果表明,注CO_(2)过程中,储层润湿性会向水湿转变,同时会发生溶蚀、重结晶已经次生矿物产生等现象,导致微米级溶蚀孔产生和亚微米、纳米喉道的堵塞,最终影响储层可动流体可注气开发效果变差,这与储层中碱性长石及硅铝酸盐含量相关。对于储层是否适合开展CO_(2)气驱具有一定指导意义。

This study conducted CO_(2)-brine-rock reaction experiment to explore the influence of reaction on reservoir wettability,microscopic pore structure,movable fluid saturation,gas flooding effect and other four aspects.The results show that CO_(2) injection process,the reservoir wettability is like water wet,corrosion will happen at the same time,the recrystallization has been creating the phenomenon such as secondary minerals,resulting in micron grade dissolution pore and sub-micron and nanometer shouted congestion,ultimately affect the movable fluid can be gas injection reservoir development effect,the alkali feldspar in the reservoir and sialic acid salt content is relevant.This study has certain guiding significance for whether the reservoir is suitable for CO_(2) gas flooding.