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:
Jul. 06, 1993
Filed:
Feb. 26, 1992
Robert M Tjon-Joe-Pin, Houston, TX (US);
Allan R Rickards, Houston, TX (US);
BJ Services Company, Houston, TX (US);
Abstract
A method of degrading a blocking gel in a subterranean formation of a well bore is shown in which a gellable blocking fluid is first formed by blending together an aqueous fluid, a hydratable polymer, a suitable crosslinking agent for crosslinking the hydratable polymer to form a polymer gel. The polymer gel may contain an enzyme breaker incorporated within. The cross-linked polymer gel is pumped into the well bore. If required, an externally applied enzyme breaker is added prior to gel degradation. The enzyme breaker is allowed to degrade the cross-linked polymer with time to reduce the viscosity of the fluid so that the fluid can be removed from the formation back to the well surface. The particular enzyme breaker utilized has an activity in the pH range from about 1.0 to 8.0 and is effective to attack only specific linkages in the cross-linked polymer gel.