CAJ | 학술논문

增强型地热系统（EGS）是采用人工形成地热储层的方法，从低渗透性岩体中经济地采出深层热能的人工地热系统。以 CO2为载热流体的增强地热能系统（CO2 EGS）是实现 CO2减排和深部地热资源开发的有效手段，系统运行时的水岩气相互作用对热储层孔渗特征有着重要影响，最终会影响储层的产热能力。笔者利用高温高压反应釜模拟 CO2 EGS 高温下的热储层盐水 CO2的相互作用，通过对实验中反应液离子成分变化和岩样扫描电镜进行分析，结果表明：实验后的钾长石和方解石出现溶解现象，且方解石溶蚀剧烈；岩样表面出现极少量次生方解石和钠长石，并有新矿物析出，其主要组成元素为 C 、O 、Si 、Fe ，为菱铁矿的中间产物。通过 TOUGHREACT 建立反应性溶质运移模型，模拟上述实验的化学反应过程，模拟结果和实验数据拟合较好。该研究可为 CO2 EGS 的水岩气作用机制提供地球化学数据。
증강형지열계통（EGS）시채용인공형성지열저층적방법，종저삼투성암체중경제지채출심층열능적인공지열계통。이 CO2위재열류체적증강지열능계통（CO2 EGS）시실현 CO2감배화심부지열자원개발적유효수단，계통운행시적수암기상호작용대열저층공삼특정유착중요영향，최종회영향저층적산열능력。필자이용고온고압반응부모의 CO2 EGS 고온하적열저층염수 CO2적상호작용，통과대실험중반응액리자성분변화화암양소묘전경진행분석，결과표명：실험후적갑장석화방해석출현용해현상，차방해석용식극렬；암양표면출현겁소량차생방해석화납장석，병유신광물석출，기주요조성원소위 C 、O 、Si 、Fe ，위릉철광적중간산물。통과 TOUGHREACT 건립반응성용질운이모형，모의상술실험적화학반응과정，모의결과화실험수거의합교호。해연구가위 CO2 EGS 적수암기작용궤제제공지구화학수거。
Enhanced geothermal system (EGS) is an engineered reservoir that has been created to extract economical amounts of heat from geothermal resources with low permeability and/or porosity . CO2 enhanced geothermal system is a technology of geological storage of carbon with geothermal energy development .When the supercritical CO2 is injected into a deep reservoir ,the surrounding rock will be dissolved or precipitated , and the porosity and permeability of the rock will also be changed . The interaction of rock‐brine‐supercritical CO2 in CO2‐EGS was simulated by high‐temperature & pressure reactor .The changes of ion compositions in the solution and scanning electron microscope of rock core showed that K‐feldspar and calcite dissolved after the experiment ,especially dissolution of calcite is too strong to be saturated .Meanwhile a very small amount of secondary calcite and albite were generated , with the generation of a new kind of mineral which is likely to be the intermediate product of siderite composed of C ,O ,Si ,and Fe .The chemical reactions in the experiments were simulated by reactive transport modelling using TOUGHREACT . The information currently available by numerical simulations is generally consistent with the results from the laboratory experiment .This study provided geochemical evidences for chemical interaction mechanisms in CO2‐EGS .