Carlos Vallejos, Tito Vasquez, Cesar Ovalles: Process for the downhole upgrading of extra heavy crude oil. Intevep, Bachman & LaPointe P C, April 6, 1999: US05891829 (63 worldwide citation)

A down hole hydroconversion process improves the viscosity, API gravity, and distillate proportions of heavy crude oils by employing a hydrogen donor, methane and steam down hole wherein the mineral formation down hole acts as a catalyst for the hydroconversion process.

Carlos Vallejos, Tito Vasquez, Gerson Siachoque, Ignacio Layrisse: Process for in SITU upgrading of heavy hydrocarbon. Intevep, Bachman & LaPointe P C, June 18, 2002: US06405799 (16 worldwide citation)

A process for in situ upgrading of a heavy hydrocarbon includes the steps of (a) positioning a well in a reservoir containing a heavy hydrocarbon having an initial API gravity of less than or equal to about 8; (b) injecting a light solvent into the well at reservoir conditions so as to provide an up ...