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Particulate matter (PM), generated during coal combustion for energy production, is a serious pollution risk to atmospheric environment. Its utilization as an industrial byproduct is an attractive endeavor all over the world. In this work, novel aqueous CO2 foam stabilized by PM from coal combustion in combination with saponin (COSA1) from camellia seed pomace was explored. Addition of COSA1 effectively promoted the dispersion of PM into the aqueous solution through adsorbing onto particle surface and increasing their zeta (ζ) potential. Hence, PM-stabilized foam could be generated much more effectively. In the presence of COSA1, PM migrated to the CO2/liquid interface and formed an “armor” surrounding the bubbles. The surface of the bubbles became solidlike and in the presence of PM, for bubble with 3.2 mM COSA1, the interfacial dilatational viscoelastic modulus dramatically increased from 23 to 65 mN/m. In addition, PM at the interface shielded CO2 gas from the surrounding liquid leading to much slower ...

A newly developed CO2–brine interfacial tension (IFT) correlation based on the alternating condition expectation (ACE) algorithm has been successfully proposed to more accurately estimate the CO2–brine IFT for a wide range of reservoir pressure, temperature, formation water salinity and injected gas composition. The new CO2–brine correlation is expressed as a function of reservoir pressure, temperature, monovalent cation molalities (Na+ and K+), bivalent cation molalities (Ca2+ and Mg2+), N2 mole fraction and CH4 mole fraction in injected gas. This prediction model is originated from a CO2–brine IFT database from the literature that covers 1609 CO2–brine IFT data for pure and impure CO2 streams. To test the validity and accuracy of the developed CO2–brine IFT model, the entire dataset was divided into two groups: a training database consisting of 805 points and a testing dataset consisting of 804 points, which was arbitrarily selected from the total database. To further examine its predicted capacity, the...

Although foamy oil can improve the performance of solution gas drive in heavy oil, only about 5–15% original oil in place (OOIP) can be recovered under primary production. In this study, a series of micromodel flood experiments and sandpack flood tests were performed to evaluate the performances of water flooding, surfactant flooding, gas flooding, and foam flooding for enhancing the recovery of Orinoco Belt heavy oil after solution gas drive. Water flooding tests show that the sweep efficiency of water flooding was low as a result of the adverse mobility ratio caused by gas bubbles dispersed in the oil; about 10.57% OOIP was obtained in the sandpack study. Surfactant flooding tests indicate that the penetration of the surfactant solution into the heavy oil and the subsequent formation of gas bubbles and emulsified oil droplets in surfactant solution could reduce the mobility of water phase, thereby improving sweep efficiency, and oil recovery of 15.09% OOIP was recovered in the sandpack. Because of the v...

Foamy oil flow has been successfully demonstrated in laboratory experiments and site application. On the basis of microscopic visualization experiments of the heavy oil from Orinoco Belt in Venezue...