Method of cyclic solvent flooding to recover viscous oils

Patent · Tue May 31 04:00:00 EDT 1983

OSTI ID:5967624

Fitch, J L; Mullins, L D

Oil may be recovered from viscous oil-containing formations including tar sand deposits by providing at least one injection well and at least one spaced-apart production well which extend downwardly from the surfaces and which extend to, and generally horizontally through, the bottom of the oil-containing formation with fluid communication of the horizontally extending portions of each well with the oil-containing formation. Solvent is injected into the injection well and fluids including oil are recovered from the production well until the fluid recovered contains an unfavorable amount of solvent, preferably at least 90 percent. After injection of the solvent is terminated, both the injection well and the production well are shut-in and the formation is allowed to undergo a soak period for a predetermined time, preferably for a time of between 2 to 20 days per foot of formation thickness. After the soak period, solvent is injected into the production well and fluids including oil are recovered from the injection well until the fluid recovered contains an unfavorable amount of solvent, preferably at least 90 percent. After injection of the solvent into the production well is terminated, both wells are shut-in and the formation is allowed to undergo a second soak period for a predetermined time, preferably for 2 to 20 days per foot of formation thickness. Thereafter, a driving fluid is injected into the formation via the injection well to effect a fluid drive of the oil through the formation and oil is produced from the production well until the oil being produced contains an unfavorable amount of driving fluid, preferably at least 90 percent.

• Assignee: Mobil Corp
• Patent Number(s): US 4385662
• OSTI ID: 5967624
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
04 OIL SHALES AND TAR SANDS
040400 -- Oil Shales & Tar Sands-- Oil Production
Recovery
& Refining
BITUMINOUS MATERIALS
CARBONACEOUS MATERIALS
ENERGY SOURCES
ENHANCED RECOVERY
FLUID INJECTION
FOSSIL FUELS
FUELS
MATERIALS
OIL SANDS
OIL WELLS
RECOVERY
SOLVENTS
WATERFLOODING
WELLS