Study on Corrosion Prediction of CO2 Flooding Well

Abstract

CO2 flooding is one of the effective measures to enhance oil recovery. In a CO2 flooding well, CO2 will cause severe acid corrosion to the tube, which will lead to safety accidents such as tube failure. Therefore, study on the pipeline corrosion caused by CO2 and pipe optimization is particularly important for safe production. This paper provided a study on the mechanism of CO2 corrosion, and a well-known commercial software was implemented to Simulate and predict corrosion status. First, the variables, such as the temperature distribution, pressure and flow rate are simulated and analyzed. On this basis, the Waard model is used to predict the influence of these parameters on the corrosion rate and find the corrosion risk point. By comparing with the measured data, the method in this paper can accurately simulate the CO2 corrosion rate of wellbore. Studies have shown that CO2 corrosion is more likely to occur in the middle of the tube. The corrosion rate first increases with the increasing of temperature, but begins to decrease after the temperature reaches a certain value. The corrosion rate is positive proportional to the partial pressure and injection speed of CO2, and is inversely related to the pipe diameter. The methods presented in this paper provide better guidance on production practices.