The Green River, Utah holds the world's greatest oil shale resources. However, the hydrocarbon, which is namely kerogen, extraction from shales is limited due to environmental and technical challenges. In this study, we investigated the effectiveness of the combustion process for shale oil extraction. Samples collected from the Green River formation were first characterized by X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). Then, series of dry combustion tests were conducted at different heating rates and wet combustion tests by water addition. The combustion efficiency was enhanced by mixing oil shale samples with an iron based catalyst. The effectiveness of dry, wet, and catalyst added combustion processes was examined by the thermal decomposition temperature of kerogen. Because the conventional oil shale extraction methods are pyrolysis (retorting) and steaming, the same experiments were conducted also under nitrogen injection to mimic retorting. It has been observed that the combustion process is a more efficient method for the extraction of kerogen from oil shale than the conventional techniques. The addition of water and catalyst to combustion has been found to lower the required temperature for kerogen decomposition for lower heating rate. This study provides insight for the optimization of the thermal methods for the kerogen extraction.
Franco, C. A. (Universidad Nacional de Colombia - Sede Medellin) | Cardona, L. (Universidad Nacional de Colombia - Sede Medellin) | Lopera, S. H. (Universidad Nacional de Colombia - Sede Medellin) | Mejía, J. M. (Universidad Nacional de Colombia - Sede Medellin) | Cortés, F. B. (Universidad Nacional de Colombia - Sede Medellin)
Heavy (HO) and extra–heavy oil (EHO) production is complicated due to its high asphaltene content that lied to adverse rheological properties. In addition, the upgrading of these unconventional oils at surface or sub-surface conditions is a low cost-effective process because of the large amounts of energy needed. Accordingly, several in-situ techniques for enhancing HO and EHO recovery with objective of upgrading the oil and improving its viscosity and mobility have been employed. In this sense, nanoparticulated catalysts have demonstrated a synergistic effect in the enhancement of oil recovery and the improvement of the pyshicochemical properties of HO and EHO such as viscosity, API gravity and content of heavy hydrocarbons such as asphaltenes. Hence, this work aims at investigate the effect of catalytic active nanoparticles in the improvement of the efficiency in recovery of a continuous steam injection process.
Nanoparticles were selected trough batch-adsorption experiments and the subsequent evaluation of the temperature for catalytic steam gasification in a thermogravimetric analyzer. A nanoparticulated support was functionalized with 2 wt% of NiO and/or PdO nanocrystals in order to improve the catalytic activity of the nanoparticles.
Also, successfully a methodology for evaluating the effect of nanoparticulated catalyst in processes of continuous vapor injection was developed. Oil recovery was evaluated using a slim tube filled with a non-confined sand pack in steam injection scenarios in absence and presence of a water-based nanofluid. The displacement test was carried out by (1) constructing the base curves, (2) estimating the oil recovery by the continuous injection of vapor in absence of nanofluid and (3) identifying the influence of the nanoparticles in the enhanced recovery of oil.
It was found that functionalized nanoparticles lead to higher adsorption of asphaltenes, higher degrees of asphaltenes self-association and lowered the temperature of