An extensive literature exists on the nature of the reactions that occur when air comes in contact with crude oil during in- situ combustion (ISC); however the effect of reservoir heterogeneity on the ISC process has not been experimentally addressed in prior studies. This paper presents the results of recent experimental efforts to shed more light on ISC. We probe the effect of pressure, temperature, injection flow-rate, nd matrix properties on the combustion of a Middle-Eastern 19.7o API oil in a tight-formation sand. The experimental perspective includes both oil oxidation kinetics and combustion-front dynamics in a 1-m long combustion tube. Most importantly, geological effects on the ISC process areinvestigated by incorporating various degrees of porous medium heterogeneity in the combustion tube runs. From the experimental data, pre and post burn CT scans of the combustion tube, and postmortem analyses, we deduce the effect of both small and large-scale heterogeneities on the spatial and temporal propagation of the combustion front.
展开▼
