Analysis of salt precipitation during CO2 injection into saline aquifers

• 1、Department of Chemical Engineering, Xi'an Jiaotong University, Xi'an 710049

Abstract：In order to analyze the phenomenon of salt precipitation during CO2 geological sequestration, a salt precipitation model was established for the CO2 injection into saline aquifers. The model includes the displacement flow of the CO2-brine phases, water evaporation, salt precipitation process and porosity reduction process. The calculation results show that the "dried out" region exists near the CO2 injection well, and the phenomenon of the solid salt precipitation occurs at the same time. The starting time and the extent of the salt precipitation depend upon the initial concentrations of brine in saline aquifers, CO2-brine displacement process and the hydraulic characteristics of geological conditions. The analysis is helpful for the prediction, assessment and alleviation of the salt precipitation problem during CO2 injection, which is of practical importance for CO2 injection into subsurface formations.

Keywords： Chemical engineering CO2 storage two phase displacement salt precipitation numerical simulation