In-depth understanding of interactions between crude oil and CO2 provides insight into the CO2-based enhanced oil recovery（EOR） process design and simulation. When CO2 contacts crude oil, the dissolution process tak...In-depth understanding of interactions between crude oil and CO2 provides insight into the CO2-based enhanced oil recovery（EOR） process design and simulation. When CO2 contacts crude oil, the dissolution process takes place. This phenomenon results in the oil swelling, which depends on the temperature, pressure, and composition of the oil. The residual oil saturation in a CO2-based EOR process is inversely proportional to the oil swelling factor. Hence, it is important to estimate this influential parameter with high precision. The current study suggests the predictive model based on the least-squares support vector machine（LS-SVM） to calculate the CO2–oil swelling factor. A genetic algorithm is used to optimize hyperparameters（у and б^2） of the LS-SVM model. This model showed a high coefficient of determination（R^2= 0.9953） and a low value for the mean-squared error（MSE = 0.0003） based on the available experimental data while estimating the CO2–oil swelling factor. It was found that LS-SVM is a straightforward and accurate method to determine the CO2–oil swelling factor with negligible uncertainty. This method can be incorporated in commercial reservoir simulators to include the effect of the CO2–oil swelling factor when adequate experimental data are not available.展开更多
A systematic series of experiments are designed and performed including inteffacial tension （IFT） measurements concomitant with Bond （BN, the ratio of gravity forces to capillary forces） and swelling/extraction me...A systematic series of experiments are designed and performed including inteffacial tension （IFT） measurements concomitant with Bond （BN, the ratio of gravity forces to capillary forces） and swelling/extraction measurements. Dynamic IFT, BN and swelling/extraction are measured as a function of pressure at temperatures of 30, 50 and 80 ℃. In addition, in the light of measured IFT the minimum miscibility pressure （MMP） of CO2 and light crude oil is determined based on a method called vanishing inteffacial tension （VIT）. The obtained results interestingly revealed that equilibrium IFT decreases linearly with pressure in two distinct pressure intervals while equilibrium BN shows an increasing trend as a function of pressure for all of the studied cases while no obvious trend is observed for swell- ing of crude oil and extraction of light-components regarding time, temperature and pressure.展开更多
基金financial support from Natural Sciences and Engineering Research Council of Canada (NSERC), Innovate NL, and Statoil Canada
文摘In-depth understanding of interactions between crude oil and CO2 provides insight into the CO2-based enhanced oil recovery（EOR） process design and simulation. When CO2 contacts crude oil, the dissolution process takes place. This phenomenon results in the oil swelling, which depends on the temperature, pressure, and composition of the oil. The residual oil saturation in a CO2-based EOR process is inversely proportional to the oil swelling factor. Hence, it is important to estimate this influential parameter with high precision. The current study suggests the predictive model based on the least-squares support vector machine（LS-SVM） to calculate the CO2–oil swelling factor. A genetic algorithm is used to optimize hyperparameters（у and б^2） of the LS-SVM model. This model showed a high coefficient of determination（R^2= 0.9953） and a low value for the mean-squared error（MSE = 0.0003） based on the available experimental data while estimating the CO2–oil swelling factor. It was found that LS-SVM is a straightforward and accurate method to determine the CO2–oil swelling factor with negligible uncertainty. This method can be incorporated in commercial reservoir simulators to include the effect of the CO2–oil swelling factor when adequate experimental data are not available.
文摘A systematic series of experiments are designed and performed including inteffacial tension （IFT） measurements concomitant with Bond （BN, the ratio of gravity forces to capillary forces） and swelling/extraction measurements. Dynamic IFT, BN and swelling/extraction are measured as a function of pressure at temperatures of 30, 50 and 80 ℃. In addition, in the light of measured IFT the minimum miscibility pressure （MMP） of CO2 and light crude oil is determined based on a method called vanishing inteffacial tension （VIT）. The obtained results interestingly revealed that equilibrium IFT decreases linearly with pressure in two distinct pressure intervals while equilibrium BN shows an increasing trend as a function of pressure for all of the studied cases while no obvious trend is observed for swell- ing of crude oil and extraction of light-components regarding time, temperature and pressure.
