INFLUENCE OF THE HEAT CARRIER ON THE COMPOSITION OF THE CRUDE-OIL EXTRACTED

The influence of the heat carrier on the thermal stability and composi tion of high-viscosity crude oil under formation conditions has been d etermined for the case of Permian productive deposits of the Mordovo-K armal' field with the use of core material from zones of heat effects, including steam and heat treatment and in situ combustion. Modelling of petroleum displacement under near-formation conditions was carried out on an experimental flow-type unit with the use of an oil-saturated core sample. Gaseous media exhibiting different chemical activity tow ards the organic matter of rock were used as the heat carriers: an oxy gen-containing atmosphere, and eluants of similar composition to the s team-gas mixtures produced by a well turbine steam-gas generator. Feat ures of the change in the composition of crude oils extracted and the increase in their thermal stability with the use of steam and gas heat carriers exhibiting lower chemical activity towards the organic matte r of rock have been established. (C) 1997 Elsevier Science Ltd.