Research on the Effect of Supercritical Carbon Dioxide on the Properties of Super Heavy Oil
Carbon dioxide flooding is an important way to exploit heavy oil reservoir. Considering the Zheng411 super heavy oil reservoir in Shengli Oil Field, the solubility of supercritical carbon dioxide in super heavy oil, and the effect of supercritical carbon dioxide on the volume factor, viscosity, component content and oil/water emulsification of super heavy oil are researched. The result shows: the solubility of carbon dioxide in super heavy oil increases with the increasing pressure, but the increasing extent declines gradually, when the pressure is below 28MPa, the solubility of carbon dioxide decreases with the rising temperature under the same saturation pressure; the volume factor increases linearly with the increase of supercritical carbon dioxide solubility; under the condition of unsaturation, the supercritical carbon dioxide is able to reduce the density of super heavy oil substantially, whereas it has little impact on the chemical properties of oil; Demulsification and visbreaking can be realized through dissolving supercritical carbon dioxide in super heavy oil that contains water, and the viscosity reduction capacity of carbon dioxide is hardly affected by water.
Weiguo Pan, Jianxing Ren and Yongguang Li
Z. M. Li et al., "Research on the Effect of Supercritical Carbon Dioxide on the Properties of Super Heavy Oil", Advanced Materials Research, Vols. 347-353, pp. 1689-1695, 2012