Compositions and methods for diverting injected fluids to achieve improved hydrocarbon fluid recovery

摘要

The present disclosure is directed to compositions and methods that may be used for enhanced oil recovery, for modifying the permeability of subterranean formations and for increasing the mobilization and/or recovery rate of hydrocarbon fluids present in the formations. The compositions may include, for example, expandable cross linked polymeric microparticles having an unexpanded volume average particle size diameter of from about 0.05 to about 5,000 microns and a cross linking agent content of from about 100 to about 200,000 ppm of hydrolytically labile silyl ester or silyl ether crosslinkers and from 0 to about 300 ppm of non-labile crosslinkers.

主权项

1. A method for improving recovery of hydrocarbon fluids from a subterranean formation comprising conditions of temperature and pH, the method comprising
injecting into the subterranean formation a composition comprising highly cross linked expandable polymeric microparticles, the microparticles having an unexpanded volume average particle size diameter that is smaller than the pores of the subterranean formation and a crosslinking agent content of from 0 to about 300 ppm of non-labile crosslinking agents and from about 100 to about 200,000 ppm of labile crosslinking agents, wherein the labile crosslinking agents comprise one or more hydrolytically labile silyl ether or silyl ester crosslinkers, and wherein the particle size is constrined by cross-linking with said labile and non-labile crosslinkers and wherein the hydrolytically labile crosslinkers break under the conditions of temperature and pH in the subterranean formation to form expanded microparticles; and recovering hydrocarbon fluids from the subterranean formation.