Method of controlling growth and heat loss of an in situ gravity draining chamber formed with a condensing solvent process

摘要

This invention is a solvent based gravity drainage process whereby the vertical growth rate of the chamber is restricted by placing, monitoring and managing a buoyant gas blanket at the top of the vapour chamber. This invention reduces the heat loss to the overburden as well as providing a means to preserve a barrier layer of bitumen saturated reservoir sand at the top of the pay zone in reservoirs where there is limited or no confining layer present.