The modeling and experimental studies on the diffusion coefficient of CO2 in saline water

Abstract

In order to study the law of migration and diffusion of CO2 in brine and promote large-scale CO2 gas sequestration projects in saline aquifers, this thesis commits a series of experiments to explore the diffusion coefficient of CO2 in saline water and the factors which may have an impact on it. Thus a set of innovative diffusion experimental installations to measure the diffusion properties of CO2 in the brine under different conditions are designed and manufactured, building a diffusion coefficient prediction mathematical model. This thesis acquires the diffusion coefficient of CO2 in the saline water under different conditions by means of laboratory experiments and analysis of the results, analyzing the influence that the factors such as temperature, injection pressure, salinity have on the diffusion coefficient of CO2 in saline water, calculating different diffusion coefficient of CO2. And thesis also applies a method which uses pH value to calculate diffusion coefficient of CO2 and acquires the result.