The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 11, 1997
Filed:
Jul. 06, 1995
Robert D Sydansk, Littleton, CO (US);
Marathon Oil Company, Findlay, OH (US);
Abstract
A process and composition are provided for permeability reduction in a treatment region to improve hydrocarbon recovery from a hydrocarbon-bearing formation. The process includes placement of a crosslinked polymer gel in the treatment region preceded by surface preparation of a gelation solution which is the gel precursor. The gelation solution contains a crosslinkable polymer, a chromium(III)/carboxylate complex crosslinking agent, a carboxylate salt delaying agent and an aqueous solvent. The gel is placed in the treatment region by injecting the gelation solution into a well bore in fluid communication with the treatment region, displacing it into the desired treatment region and gelling the solution to completion forming the permeability-reducing gel in situ. The gelation rate is retarded in a controlled manner by adjusting the composition or concentration, and correspondingly the pH, of the delaying agent in the gelation solution.