Abstract: A process for thermally stimulating and upgrading oil production from a heavy oil reservoir wherein the heavy oil produced from the reservoir is combined with a hydrogen donor diluent and the mixture is subjected to thermal cracking to upgrade the heavy oil into more valuable hydrocarbon products. The cracked products are fractionated into a light end vapor fraction, an intermediate liquid fraction, a gas oil fraction and a pitch fraction, and at least a portion of the gas oil fraction is hydrogenated by contacting it with a hydrogen-containing gas stream to produce the hydrogen donor diluent combined with the heavy oil. The pitch fraction is subjected to partial oxidation to produce the hydrogen-containing gas stream and a by-product gas stream containing steam which is combined with additional steam and injected into the heavy oil reservoir to enhance the mobility of heavy oil contained therein.

Abstract: Shale oil is recovered from a horizontal oil shale deposit having an exposed vertical surface by:(a) tunneling a horizontal sloping tunnel under a portion of the deposit, optionally using material removed from the tunnel to form a service terrace,(b) shaping and lining the floor of the tunnel to form a covered sump sloping to the tunnel mouth,(c) explosively rubblizing the roof and walls of the tunnel, and(d) fireflooding the rubblized zone to retort the kerogen which produces shale oil at the tunnel face through the sump.The fireflood is preferably by wet combustion which can be either forward or reverse combustion. Oxygen containing gas can be injected through a vertical bore from the surface or from the tunnel face. In one embodiment, the fireflood is prevented from channeling across the top of the rubblized zone by leaving segments of the roof to project downward at intervals. The vertical surface of the deposit can be naturally exposed or exposed by a large diameter bore hole or a vertical mine shaft.

Abstract: A hydrogen donor diluent cracking process for upgrading a heavy liquid hydrocarbon wherein pitch fractionated from the cracked products is subjected to a partial oxidation process to reduce the amount of pitch and to provide hydrogen for hydrogenation of hydrogen donor diluent for the cracking step.