Patent ID: 10308860

Abstract:
Compositions for removing filter cake from a subterranean borehole and methods for degrading filter cake and filter cake removal are provided. The composition contains an encapsulated peroxygen (e.g., acrylic resin coated ammonium persulfate), a surfactant (e.g., nonionic surfactant), and optionally an unencapsulated peroxygen. The method (e.g., a one-step method) involves contacting the filter cake with the composition, and allowing the composition to remain in contact with the filter cake for a period of time sufficient to degrade the filter cake. The reaction of the composition with the filter cake results in acidic conditions, thereby eliminating any need for follow up acid treatments. The composition is stable enough to effectively remove filter cake at temperatures up to 250° F. or greater. Through filter cake removal, the method provides for increased flow, production, and/or recovery of oil and gas hydrocarbons from a subterranean formation.