COMPOSITION AND METHOD FOR RECOVERING HYDROCARBON FLUIDS FROM A SUBTERRANEAN RESERVOIR

摘要

A composition including crosslinked expandable polymeric microparticles capable of hydrolysis at or below neutral pH and a method of modifying the permeability to water of a subterranean formation by introducing such compositions into the subterranean formation. This disclosure further relates to compositions and methods for the recovery of hydrocarbon fluids from a subterranean reservoir or formation subjected to CO2 or CO2 Water Alternating Gas flooding at low pH and increases the mobilization and/or recovery rate of hydrocarbon fluids present in the subterranean formations.

主权项

1. A method of modifying the permeability to water of a subterranean formation, the method comprising: introducing into the subterranean formation a composition comprising crosslinked expandable polymeric microparticles having an unexpanded volume average particle size diameter from about 0.05 to about 2,000 microns, and a crosslinking agent content from about 50 to about 200,000 ppm of at least one labile crosslinker based on a molar ratio of said polymeric microparticles capable of cleavage at or below neutral pH and from 0 to about 900 ppm of at least one non-labile crosslinker based on a molar ratio, wherein the microparticles have a smaller diameter than a diameter of pores of the subterranean formation and wherein the labile crosslinkers break under the conditions in the subterranean formation to form expanded polymeric microparticles.