ENHANCED HEAVY OIL RECOVERY USING DOWNHOLE BITUMEN UPGRADING WITH STEAM ASSISTED GRAVITY DRAINAGE

摘要

Methods for recovery of heavy oils use selective catalytic downhole upgrading with SAGD technology. Certain embodiments include extracting heavy oil using a SAGD process and upgrading the heavy oil in a production well with a cracking catalyst. The cracking catalyst is introduced into the production well, allowing the extracted hydrocarbons to interface with the cracking catalyst to upgrade the hydrocarbons. The upgraded hydrocarbons are then separated from the cracking catalyst. This upgraded stream has a lower molecular weight, significantly reducing the viscosity of the produced hydrocarbons. A gasifier is provided to gasify a portion of the slurry containing unconverted heavy oil and cracking catalyst to produce syngas. The syngas may then be used to produce steam for use in the SAGD extraction process, improving energy efficiency of the process. Further, formation catalyst losses are avoided as the catalyst injected into the well is recovered and available for reuse.