KINETICS OF IN SITU COMBUSTION PROCESS: A REVIEW OF KINETIC MODELS

In situ combustion is a thermal enhanced heavy oil recovery method in which a portion of the oil is burned (approximately 10%) due to the reaction with oxygen or any other oxidant gas with the purpose of generating energy as heat. In this process air reacts with the reservoir oil ( in situ) resulting the low temperature reactions (LTO, Low Temperature Oxidation) or addition reactions, later the cracking reactions take place (ITO, Intermediate Temperature Oxidation) which produce the coke necessary for the combustion. As the temperature increase, the high temperature reactions occur (HTO, High Temperature Oxidation) in which the fuel is consumed generating the combustion front. In this article is done a theorical review of the kinetics on In Situ Combustion processes, with emphasis on dry frontal combustion for heavy oil, which collects the reactions mechanisms of each of the temperature regimes ( low temperature or addition, intermediate temperature of thermal cracking and high temperature or breaking bonds) and the reaction models widely reported on the literature with the kinetic associated to there. These include the following models: Belgrave, Benham and Poettmann, Sequera, Kapadia, and Pruden, between others. Knowledge of the kinetics constitute an start point for the process analysis on In Situ Combustion, its importance lies that for making an In Situ Combustion project, is necessary to make laboratory tests to determine the kinetics of the reaction and also, to establish the whole set of reactions that best represent the oxidative behavior of the studied oil. The final objective of this review is to establish the most representative kinetic models for the Colombian crude.