Oil recovery process using an emulsion modifier-containing dilute aqueous surfactant system

Patent · Tue Jan 23 00:00:00 EST 1973

OSTI ID:7215979

Hill, H J; Thigpen, D R

An oil-phase-external surfactant system tends to form a relatively viscous emulsion upon contact with reservoir oil. A surfactant system was designed to include emulsion modifiers, which would decrease the viscosity of any emulsion formed and permit its removal from the reservoir by the surfactant slug. The surfactant slug contained sodium petroleum sulfonate (average molecular weight 460/470), Neodol 25--3S (a surfactant sulfate of an ethoxylated primary alcohol), Pyronate 30 (a water soluble sodium sulfonate), isobutyl alcohol, Pusher 700 (a partially hydrolyzed polyacrylamide), and brine (3,900 ppM total dissolved solids). The Neodol was included to disperse the sulfonate in water and provide needed multi-valent ion tolerance. Both the isobutyl alcohol and Pyronate were emulsion modifiers. Of the emulsion modifiers tested, the alcohol was uniquely effective in its ability to increase the coalescence rate of emulsions, thus improving the mobility ratio of the emulsion and slug and permitting removal of the emulsion. A Berea core was saturated, flooded with crude, and waterflooded. A recovery of 96% of residual oil was obtained using 1.36 PV of the adjusted oil-phase-external surfactant slug, followed by a thickened flood of Pusher in fresh lake water.

• Assignee: Shell Oil Co.
• Patent Number(s): US 3712377
• OSTI ID: 7215979
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
OIL WELLS
WATERFLOODING
ENHANCED RECOVERY
PETROLEUM
PETROLEUM SULFONATES
SANDSTONES
SURFACTANTS
ENERGY SOURCES
ESTERS
FLUID INJECTION
FOSSIL FUELS
FUELS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
ROCKS
SEDIMENTARY ROCKS
SULFONATES
SULFONIC ACID ESTERS
WELLS
020300* - Petroleum- Drilling & Production