Steam injection and in situ combustion: A combined approach to heavy oil recovery.

摘要

A series of four laboratory combustion tube experiments was carried out to examine the combination of the steamflooding and combustion processes on heavy oil cores from the Primrose Reservoir. The effects of pressure, oxygen enrichment, and injection flux were examined, as well as incremental oil recovery during the waterflood, steamflood, and combustion phases. It was found that steam efficiency decreased as pressure increased; however, steam developed a highly mobile low oil saturation which enhanced the combustion process. The process operated very efficiently at low initial oil saturations when the core had been preheated and swept by steam. Low oxygen concentration and high gas flux maintained stable combustion at pressures as high as 10.3 MPa. The combination of steamflooding and in-situ combustion as an enhanced oil recovery process has potential future application in the low mobile and highly viscous oil of Canadian heavy oil reserves.