Middle phase microemulsion to liquid crystal transition in surfactant systems for EOR

Conference · Wed Jan 01 04:00:00 EST 1986

OSTI ID:7159616

Hackett, J L; Miller, C A

The phase behavior of two anionic surfactant systems, one containing a commercial alpha olefin sulfonate, and the other pure sodium dodecyl sulfate (SDS), was determined in the region where a transition from microemulsion to liquid crystalline phases occurred with decreasing alcohol content and decreasing temperature. A general and rather complex pattern of phase behavior was seen which included a four-phase coexistence region of brine, microemulsion, lamellar liquid crystal, and oil and two three-phase regions containing both microemulsion and liquid crystal. In much of the four-phase region, complete separation of the phases did not occur even after equilibration for a year or more at constant temperature. Instead, oil and brine we observed to coexist with stable birefringent dispersions which, at least for some compositions, apparently contained three phases: microemulsion, liquid crystal, and oil. Solubilization of brine was uniformly low in the phases making up the dispersions. The dispersions in the SDS system exhibited non-Newtonian behavior with apparent viscosities in the range of 50-100 mPa . s at a shear rate of 10 sec/sup -1/. Microemulsion viscosities in the same system were about an order of magnitude lower. No plugging or other adverse behavior was seen when such dispersions flowed at a velocity of 10/sup -5/ m/s (3 ft/day) through a model porous medium having pore sizes comparable to those in reservoirs. In preliminary experiments, selected dispersions appeared to be capable of displacing oil from the same model porous medium.

• Research Organization: Rice Univ.
• OSTI ID: 7159616
• Report Number(s): CONF-861080-
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
ALCOHOLS
ALKALI METAL COMPOUNDS
ALKENES
ANIONS
BRINES
CHARGED PARTICLES
CHEMICAL COMPOSITION
COLLOIDS
CRYSTAL STRUCTURE
CRYSTAL-PHASE TRANSFORMATIONS
CRYSTALS
DISPERSIONS
DISPLACEMENT FLUIDS
EMULSIONS
ENERGY SOURCES
ENHANCED RECOVERY
EQUILIBRIUM
FLUID INJECTION
FLUIDS
FOSSIL FUELS
FUELS
HYDROCARBONS
HYDROXY COMPOUNDS
IONS
LIQUID CRYSTALS
LIQUIDS
MICROEMULSION FLOODING
MICROEMULSIONS
MICROSTRUCTURE
MISCIBLE-PHASE DISPLACEMENT
OIL WELLS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
OXYGEN COMPOUNDS
PETROLEUM
PHASE STUDIES
PHASE TRANSFORMATIONS
POROSITY
RECOVERY
RESERVOIR ROCK
SCALE MODELS
SIMULATION
SODIUM COMPOUNDS
SODIUM SULFATES
STIMULATION
STRUCTURAL MODELS
SULFATES
SULFONATES
SULFUR COMPOUNDS
SURFACTANTS
TEMPERATURE EFFECTS
VISCOSITY
WELL STIMULATION
WELLS