Investigation of the fate of O2 contaminant in combined CO2 flooding sequestration process

The fate of oxygen contaminant in a carbon dioxide (CO2) miscible flood/sequestration project was examined along with the economic implications of CO2 capture from stack gases which is subsequently injected as a miscible agent into a light oil reservoir. The presence of oxygen in injected carbon dioxide streams promotes corrosion and can cause degradation of the oil through low temperature oxidation reactions. The maximum levels of oxygen that can be tolerated in CO2 during miscible flooding was also examined by measuring the effects of different levels of oxygen concentration on the rate of oxygen consumption from the gas phase. Measurements were taken of the changes in oil composition and emulsion forming characteristics of the partially oxidized oil. The effect of reservoir material, temperature and reaction time were also examined and a low-temperature oxidation kinetic model was applied to determine the composition of pseudo-components. The study offers new information about the fate of oxygen contaminant and provides guidelines for residual oxygen as an impurity in the carbon dioxide feed to a CO2 miscible/sequestration project