IN SITU COMBUSTION IN ENHANCED OIL RECOVERY (EOR): A REVIEW

Abstract

Enhanced oil recovery (EOR) refers to the technologies developed to increase extraction of crude oil from reservoirs after primary production. In situ combustion (ISC) is one of the methods developed for EOR. This review examines studies done by researchers worldwide to improve our understanding of the mechanism of oil cracking kinetics, which is one of the fundamental mechanisms of in situ combustion. Good agreement between the laboratory and field results has encouraged further research in this field. Extensive research at the laboratory scale to understand the pyrolysis and oxidation behavior of coke formed from medium and light oil and also to propose more realistic models to mimic the true behavior of in situ combustion has been undertaken in recent years. Apart from the classical Arrhenius model, researchers have come up with other models (two-step oxidation model) based on the type of combustion activity observed from their samples, thus modeling the process more accurately. Research work showing optimization of the parameters of ISC and improving the economic viability of the entire process is been one of the main focuses of this article. The review also explains the nature of the various experiments, sheds light on some of the concepts that remain unexplained, and opens the way for fresh thinking in those areas. It also highlights the possibility of developing global solutions for numerical simulation of this EOR process.

Keywords:

• Combustion
• Enhanced oil recovery
• In situ combustion
• Pyrolysis
• Reaction kinetics

Acknowledgments

The authors wish to acknowledge the financial support extended by the Petroleum Technology Research Centre (PTRC) and Natural Science and Engineering Research Council (NSERC) to conduct pyrolysis and combustion experiments, a part of which has been included in this review. Thanks to Dr. Gordon Moore, Professor, University of Calgary, for his valuable feedback on this review.