Method of gravel packing a well
US5363916A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 16, 1993 |
| Grant date | Nov 15, 1994 |
| Priority date | — |
| Expiry date | Jun 16, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S507/926
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The present invention provides a method of gravel packing a subterranean formation using a gel of a graft copolymer of a hydroxyalkyl cellulose prepared by a redox reaction with vinyl phosphonic acid. The gel is formed by hydrating the graft copolymer in an aqueous liquid. The gel in crosslinked by the addition of a crosslink initiator comprising a Lewis base or Bronsted-Lowry base, which is substantially free of polyvalent metal ions, to the gel in an amount sufficient to effect crosslinking of the graft copolymer. The viscosity of the crosslinked gel is reduced by contacting the gel with an acidic fluid whereby the pH of the gel is caused to decrease. The reduction in gel viscosity facilitates formation of the gravel pack.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.