[H-RE31_2AM2] Climate control and geosciences (CCS,CO2-EOR,CCUS,geoengineering)

[HRE31-10] Dawsonite synthesis/dissolution experiment under the relevant condition of CO₂ underground storage

Yutaro TAKAYA¹, *Kentaro NAKAMURA², Yasuhiro KATO¹ (1.Frontier Research center for Energy and Resoueces (FRCER), Graduate School of Engineering, Universit, 2.Department of Systems Innovation, Graduate School of Engineering, University of Tokyo)

Keywords:CO₂ underground storage, mineral trapping, dawsonite

Geochemical trapping is a mechanism for defining the longer-term security of CO₂ underground storage. Especially, mineral trapping improves the storage security by the transformation reaction of injected CO₂ (liquid or supercritical phase) to carbonate minerals. Recently, several studies based on the computer simulation predicted the formations of dawsonite (NaAlCO₃ (OH) ₂) as an initial phase of mineral trapping and that dawsonite may play important role for the storage security in the early stage of CO₂ storage. However, it has not been reported the formation of dawsonite in the experiments under the relevant condition of the CO₂ underground storage to date and the problem ''whether dawsonite will be formed in the CO₂ reservoir and will contribute the improvement of the CO₂ storage security'' is still remaining. In this study, therefore, we conduct the synthesis/dissolution experiments of dawsonite under the CO₂ reservoir condition and discuss the formation/preservation condition of dawsonite. We further discuss the possibility of dawsonite formation in the CO₂ reservoir based on our experimental results.