Geological storage of carbon dioxide (CO2) into deep saline aquifers is a leading-edge technology of greenhouse gas emissions reduction. The paper investigates China's first full-chain carbon capture and storage (CCS) project

i.e. Shenhua CCS demonstration project. Combining actual operation condition

the site of demonstration project in Ordos Basin is selected for the study. The relevant parameters are extracted to establish the geological model that is used to simulate multilayer injection of CO2 into deep saline aquifers. In order to analyze migration and distribution of CO2 while and after injection

the relationship between injection capacity and storage mechanisms of CO2 is investigated in detail. Additionally

it is also investigated on changes of formation pressure

CO2 phase

CO2 mole fraction and pH value. The numerical simulation shows that when CO2 is injected into deep saline aquifers

it is almost sequestered into the top of the reservoir. When the injection capacity is stronger

CO2 is injected into more layer formations

and the injection volume of CO2 is relatively bigger. The injected CO2 bears a very complicated phase state in deep saline aquifers. It is mixed with a free gas

trapped and dissolved phases. Simultaneously

when an injection rate is different

main phase types of injected CO2 into deep saline aquifers are different and they change with time. The change pattern of pH values is also different because of strength of seepage effect caused by different injection rates. All exploratory studies are aiming at building a good foundation to optimize future schemes of the demonstration project.