The Sensitivity Analysis of Wellbore Heat Transfer during the CO<sub>2</sub> Injection Process

Abstract

The sensitivity analysis of wellbore heat transfer during the CO2injection process is of vital importance to Carbon dioxide utilization and sequestration (CCUS). A numerical simulation method is developed to simulate the process of wellbore heat transfer during injecting carbon dioxide by amending the classical heat transfer modelRamey models. It analyses how the selected parameters affect the distribution of the wellbore temperature and pressure, which include CO2injection temperature, pressure and density, the injection flow rate and Joule Thomson coefficient. The results show that, CO2injection temperature has greater impact on the initial level of the temperature distribution; higher injection pressure raises the temperature mainly because of the effect of Joule Thomson coefficient; also, when the injection process lasts a longer time, the distribution is much more stable. When the injection flow rate is higher, the strata temperature has less influence on the flow temperature. The injection pressure and density has very appreciable effect on the pressure distribution. However, the other parameters have less influence on it. The modified simulation method was applied in Jiangsu Caoshe oil field and the simulation results coincided with the measuring data well.