The development of new technologies to increase oil recovery and the improvement of old ones has become increasingly important in the world. One of such methods is based on in-situ combustion, which in reference to light oils is termed as High Pressure Air Injection – HPAI. There are a number of projects of air injection into light and heavy oil fields described in literature. Some of them are successfully operated for many years and up to this day. The in-situ combustion process is attended with CO and CO2 formation as well as thermal decomposition processes resulting in hydrocarbon gases output and fuel formation. The improvement in oil recovery is caused by contribution of several processes – rise of reservoir pressure and temperature, oil density and viscosity reduction under heating, evaporation-condensation of water, nitrogen and fuel gases displacement, dilution of oil due to dissolution of carbon dioxide, and many others. Nowadays there is no systematic and comprehensive approach to all the mentioned phenomena. That causes considerable risks in project’s efficiency and total oil recovery estimation. The present work includes theoretical and experimental study of the processes associated with HPAI. The first stage includes calorimetric study of oxidation process in differential scanning calorimeter (DSC) and kinetic parameters estimation (activation energy, pre-exponential factor, reactions’ rate and order etc.), which are then applied for in situ combustion modeling. In term of theoretical investigations the mathematical model of in-situ combustion based on experimental data is formulated. The model includes heat- and mass-transfer in three-phase multi-component system in porous medium. The mathematical model is also constructed to make the attempt to investigate some transition processes – in-situ ignition, attenuation and re-igniting. Set of dimensionless parameters is formulated which allow predicting the quality of in-situ-combustion of oil. Large number of geological and physical parameters responsible for the in-situ-combustion is reduced to the analysis of two dimensionless parameters. The conditions for development of self-sustained oxidation reaction in porous medium are obtained that is summarized in a form of ignition-combustion diagram for in-situ-combustion process. The modeling results will be calibrated with combustion tube experimental data, as well as the results will be used to perform some combustion cases with the tube. The main goal of the project is to enhance predictability of the modeling and reduce risks associated with HPAI.


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