CAJ | 학술논문

由于盖层中可能存在未知断层和裂隙或被废弃井穿透，储存于深部地层的 CO2会发生向上运移泄漏影响浅层地下水水质，在天然流场的作用下，受影响含水层在泄漏停止后，可能表现出一定的自我修复能力。以美国某野外试验场地为例，以 TOUGHREACT 软件为平台，模拟分析当 CO2泄漏停止后含水层的自我修复能力。结果表明：CO2泄露进入含水层会降低地下水中的 pH 值，从而引起地下水中碳酸盐矿物（本次研究中为方解石矿物）的溶解发生；当泄漏停止后，在天然流场的作用下，地下水中 pH 值逐渐回升，说明天然条件下的含水层对 pH 值具有一定的自我修复能力，但在修复过程中，由于沿途方解石矿物的溶解，使得地下水中 Ca 的浓度值逐渐升高，研究区天然流场对地下水中的 Ca 修复效果不佳。
유우개층중가능존재미지단층화렬극혹피폐기정천투，저존우심부지층적 CO2회발생향상운이설루영향천층지하수수질，재천연류장적작용하，수영향함수층재설루정지후，가능표현출일정적자아수복능력。이미국모야외시험장지위례，이 TOUGHREACT 연건위평태，모의분석당 CO2설루정지후함수층적자아수복능력。결과표명：CO2설로진입함수층회강저지하수중적 pH 치，종이인기지하수중탄산염광물（본차연구중위방해석광물）적용해발생；당설루정지후，재천연류장적작용하，지하수중 pH 치축점회승，설명천연조건하적함수층대 pH 치구유일정적자아수복능력，단재수복과정중，유우연도방해석광물적용해，사득지하수중 Ca 적농도치축점승고，연구구천연류장대지하수중적 Ca 수복효과불가。
Because of the unknown faults,fractures in the cap rock,the deep stored CO2 may move upward,the intrusion will impact shallow groundwater quality.After the leakage stopped,the affected aquifer may show self-repair capacity under the natural flow field.In this study,an injection test field was selected as example,and the reactive transport modeling software TOUGHREACT was used to simulate the self-repair capacity.The simulation results showed that,the intrusion of leaked CO2 would decrease the pH of target aquifer,and trigger the dissolution of carbonate minerals.After the leakage stopped,the pH would be increased under natural conditions,but the concentration of Ca would increased because of the dissolution of calcite along the flow path,which means the self-repair capacity of target aquifer is not good enough to scavenge the impacts of CO2 leakage.