Numerical Simulation of Thermo-Hydro-Mechanical-Chemical Response Caused by CO_(2)Injection into Saline Geological Formations:A Case Study from the Ordos Project,China  

作　　者：FAN Zejin XU Tianfu YANG Bo ZHANG Hui ZHU Huixing 

机构地区：[1]Key Laboratory of Groundwater Resources and the Environment,Ministry of Education,Jilin University,Changchun 130021,China [2]Jilin Provincial Key Laboratory of Water Resources and the Environment,Jilin University,Changchun 130021,China

出　　处：《Acta Geologica Sinica(English Edition)》2023年第3期889-910,共22页地质学报（英文版）

基　　金：jointly supported by the National Natural Science Foundation of China(Grant No.42141013);the CNPC Innovation Found(2021 D002-1102);the China Postdoctoral Science Foundation(No.2021M701379)。

摘　　要：Thermo-hydro-mechanical-chemical(THMC)interactions are prevalent during CO_(2)geological sequestration(CGS).In this study,a sequential coupling THMC numerical simulation program was constructed,which can be used to explore the following issues of CGS:fluid and heat flow,solute transport;stresses,displacements and rock failures related to geo-mechanical effects;equilibrium and kinetic chemical reactions;chemical damage to mechanical properties of the rock.Then,the coupling program was applied to the Ordos CGS Project to study the formation response under the multifield interaction caused by CO_(2)injection.The simulation results show that the mechanical process dominates the short CO_(2)injection period.Specifically,the formation’s permeability near the injection well increases by 43%,due to the reduction of effective stress,which significantly promotes the lateral migration of CO_(2).When the injection rate exceeds 0.15 million tons per year,the cohesion of the reservoir rock is not enough to resist the shear force inside the rock and rock failure may occur.During the subsequent long-term sequestration period(200 years),the influence of mineral reactions gradually increases.Due to calcite dissolution,the shear modulus of caprock is predicted to decrease by 7.6%,which will to some extent increase the risk of rock failure.

关 键 词：CO_(2) geological sequestration THMC coupling numerical simulation chemical damage 

分 类 号：X701[环境科学与工程—环境工程] TU45[建筑科学—岩土工程]