This work systematically reviews the complex mechanisms of CO_(2)-water-rock interactions,microscopic simulations of reactive transport(dissolution,precipitation and precipitate migration)in porous media,and microscop...This work systematically reviews the complex mechanisms of CO_(2)-water-rock interactions,microscopic simulations of reactive transport(dissolution,precipitation and precipitate migration)in porous media,and microscopic simulations of CO_(2)-water-rock system.The work points out the key issues in current research and provides suggestions for future research.After injection of CO_(2) into underground reservoirs,not only conventional pressure-driven flow and mass transfer processes occur,but also special physicochemical phenomena like dissolution,precipitation,and precipitate migration.The coupling of these processes causes complex changes in permeability and porosity parameters of the porous media.Pore-scale microscopic flow simulations can provide detailed information within the three-dimensional pore and throat space and explicitly observe changes in the fluid-solid interfaces of porous media during reactions.At present,the research has limitations in the decoupling of complex mechanisms,characterization of differential multi-mineral reactions,precipitation generation mechanisms and characterization(crystal nucleation and mineral detachment),simulation methods for precipitation-fluid interaction,and coupling mechanisms of multiple physicochemical processes.In future studies,it is essential to innovate experimental methods to decouple“dissolution-precipitation-precipitate migration”processes,improve the accuracy of experimental testing of minerals geochemical reaction-related parameters,build reliable characterization of various precipitation types,establish precipitation-fluid interaction simulation methods,coordinate the boundary conditions of different physicochemical processes,and,finally,achieve coupled flow simulation of“dissolution-precipitation-precipitate migration”within CO_(2)-water-rock systems.展开更多
To investigate the impacts of mineral composition on physical and mechanical properties of carbonate rocks,limestone specimens containing different contents in calcite and dolomite are selected to perform CO_(2)-water...To investigate the impacts of mineral composition on physical and mechanical properties of carbonate rocks,limestone specimens containing different contents in calcite and dolomite are selected to perform CO_(2)-water-rock reaction experiments.The X-ray Diffraction(XRD) and Nuclear Magnetic Resonance(NMR) are carried out to examine the change characteristics of mineral dissolution and pore structure after reaction.The core flooding experiments with Fiber Bragg gratings are implemented to examine the stress sensitivity of carbonate rocks.The results show that the limestones containing pure calcite are more susceptible to acid dissolution compared to limestone containing impure dolomite.The calcite content in pure limestone decreases as the reaction undergoes.The dissolution of dolomite leads to the formation of calcite in impure limestone.Calcite dissolution leads to the formation of macropore and flow channels in pure limestone,while the effects of impure dolomite in impure limestone results in mesopore formation.When confining pressure is lower than 12 MPa,pure limestones demonstrate higher strain sensitivity coefficients compared to impure limestone containing dolomite after reaction.When confining pressure exceeds 12 MPa,the strain sensitivity coefficients of both pure and impure limestones become almost equal.展开更多
The stability of dawsonite is an important factor affecting the feasibility evaluation of CO_(2)geological storage.In this paper,a series of experiments on the interaction of CO_(2)-water-dawsonite-bearing sandstone w...The stability of dawsonite is an important factor affecting the feasibility evaluation of CO_(2)geological storage.In this paper,a series of experiments on the interaction of CO_(2)-water-dawsonite-bearing sandstone were carried out under different CO_(2)pressures.Considering the dissolution morphology and element composition of dawsonite after the experiment and the fluid evolution in equilibrium with dawsonite,the corrosion mechanism of dawsonite led by CO_(2)partial pressure was discussed.The CO_(2)fugacity of the vapor phase in the system was calculated using the Peng-Robinson equation of state combined with the van der Waals 1-fluid mixing rule.The experimental results indicated that the thermodynamic stability of dawsonite increased with the increase of CO_(2)partial pressure and decreased with the increase of temperature.The temperature at which dawsonite dissolution occurred was higher at higher f_(CO_(2)).There were two different ways to reduce dawsonite’s stability:the transformation of constituent elements and crystal structure damage.Dawsonite undergoes component element transformation and crystal structure damage under different CO_(2)pressures with certain temperature limits.Based on the comparison of the corrosion temperature of dawsonite,three corrosion evolution models of dawsonite under low,medium,and high CO_(2)pressures were summarized.Under conditions of medium and low CO_(2)pressure,as the temperature continued to increase and exceeded its stability limit,the dawsonite crystal structure was corroded first.Then the constituent elements of dawsonite dissolved,and the transformation of dawsonite to gibbsite began.At high CO_(2)pressure,the constituent elements of dawsonite dissolved first with the increase of temperature,forming gibbsite,followed by the corrosion of crystalline structure.展开更多
基金Supported by the National Natural Science Foundation of China(52234003,52222402,52304044).
文摘This work systematically reviews the complex mechanisms of CO_(2)-water-rock interactions,microscopic simulations of reactive transport(dissolution,precipitation and precipitate migration)in porous media,and microscopic simulations of CO_(2)-water-rock system.The work points out the key issues in current research and provides suggestions for future research.After injection of CO_(2) into underground reservoirs,not only conventional pressure-driven flow and mass transfer processes occur,but also special physicochemical phenomena like dissolution,precipitation,and precipitate migration.The coupling of these processes causes complex changes in permeability and porosity parameters of the porous media.Pore-scale microscopic flow simulations can provide detailed information within the three-dimensional pore and throat space and explicitly observe changes in the fluid-solid interfaces of porous media during reactions.At present,the research has limitations in the decoupling of complex mechanisms,characterization of differential multi-mineral reactions,precipitation generation mechanisms and characterization(crystal nucleation and mineral detachment),simulation methods for precipitation-fluid interaction,and coupling mechanisms of multiple physicochemical processes.In future studies,it is essential to innovate experimental methods to decouple“dissolution-precipitation-precipitate migration”processes,improve the accuracy of experimental testing of minerals geochemical reaction-related parameters,build reliable characterization of various precipitation types,establish precipitation-fluid interaction simulation methods,coordinate the boundary conditions of different physicochemical processes,and,finally,achieve coupled flow simulation of“dissolution-precipitation-precipitate migration”within CO_(2)-water-rock systems.
基金partially supported by Creative Group of Natural Science Foundation of Hubei Province (Grant No. 2021CFA030)National Natural Science Foundation of China (Grant No. 41872210)。
文摘To investigate the impacts of mineral composition on physical and mechanical properties of carbonate rocks,limestone specimens containing different contents in calcite and dolomite are selected to perform CO_(2)-water-rock reaction experiments.The X-ray Diffraction(XRD) and Nuclear Magnetic Resonance(NMR) are carried out to examine the change characteristics of mineral dissolution and pore structure after reaction.The core flooding experiments with Fiber Bragg gratings are implemented to examine the stress sensitivity of carbonate rocks.The results show that the limestones containing pure calcite are more susceptible to acid dissolution compared to limestone containing impure dolomite.The calcite content in pure limestone decreases as the reaction undergoes.The dissolution of dolomite leads to the formation of calcite in impure limestone.Calcite dissolution leads to the formation of macropore and flow channels in pure limestone,while the effects of impure dolomite in impure limestone results in mesopore formation.When confining pressure is lower than 12 MPa,pure limestones demonstrate higher strain sensitivity coefficients compared to impure limestone containing dolomite after reaction.When confining pressure exceeds 12 MPa,the strain sensitivity coefficients of both pure and impure limestones become almost equal.
基金The authors thank the editors and two anonymous reviewers for their careful check and helpful comments and modification of the manuscript.This study is financially supported by the National Natural Science Foundation of China(Grants Nos.42072130 and 41872152).
文摘The stability of dawsonite is an important factor affecting the feasibility evaluation of CO_(2)geological storage.In this paper,a series of experiments on the interaction of CO_(2)-water-dawsonite-bearing sandstone were carried out under different CO_(2)pressures.Considering the dissolution morphology and element composition of dawsonite after the experiment and the fluid evolution in equilibrium with dawsonite,the corrosion mechanism of dawsonite led by CO_(2)partial pressure was discussed.The CO_(2)fugacity of the vapor phase in the system was calculated using the Peng-Robinson equation of state combined with the van der Waals 1-fluid mixing rule.The experimental results indicated that the thermodynamic stability of dawsonite increased with the increase of CO_(2)partial pressure and decreased with the increase of temperature.The temperature at which dawsonite dissolution occurred was higher at higher f_(CO_(2)).There were two different ways to reduce dawsonite’s stability:the transformation of constituent elements and crystal structure damage.Dawsonite undergoes component element transformation and crystal structure damage under different CO_(2)pressures with certain temperature limits.Based on the comparison of the corrosion temperature of dawsonite,three corrosion evolution models of dawsonite under low,medium,and high CO_(2)pressures were summarized.Under conditions of medium and low CO_(2)pressure,as the temperature continued to increase and exceeded its stability limit,the dawsonite crystal structure was corroded first.Then the constituent elements of dawsonite dissolved,and the transformation of dawsonite to gibbsite began.At high CO_(2)pressure,the constituent elements of dawsonite dissolved first with the increase of temperature,forming gibbsite,followed by the corrosion of crystalline structure.
