CO2-水-页岩相互作用的研究现状及展望

简要综述了CO2、水和页岩间矿物的相互作用,分析了CO2注入到地下进入页岩层后,地下含水层pH值的变化,并根据页岩层的矿物学组成分为黏土矿物和脆性矿物,较为详细地描述了CO2与黏土矿物和脆性矿物之间发生的地球化学反应,概述了此反应对页岩层孔隙度和渗透率的影响。同时,也讨论了CO2增强页岩气开采的现实问题及发展趋势,为今后的研究提供了参考。

Review and Prospects of the CO2-water-shale Interactions

The greenhouse effect is exacerbating global climate problems,and a key mechanism that can mitigate climate change is reducing the total amount of greenhouse gases emitted to the atmosphere.Carbon dioxide capture,use,and storage(CCUS)technology is a storage technology that scientists currently recognize as feasible.Among them,deep formations are the best place for CO2 geology.However,scientists have studied more about sandstone reservoirs and relatively few studies on shale.However,shale reservoirs also have large storage capacity and should not be ignored.This paper briefly reviews the interactions between CO2,water and shale minerals,analyzes the change of pH value of underground aquifer after CO2 injection into the shale formation,and divides it into clay minerals and brittle minerals according to the mineralogical composition of the shale formation.The geochemical reactions between CO2 and clay minerals and brittle minerals are described in more detail.The effects of this reaction on shale porosity and permeability are summarized.Meanwhile,this paper also discusses the practical problems and development trends of CO2 enhanced shale gas mining,and provides reference for future research.