Patent · US Expired

Aqueous gels for plugging fractures in subterranean formation and production of said aqueous gels

US3955998A · kind A · utility

71Cited by
3References
23Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 18, 1974
Grant dateMay 11, 1976
Priority date
Expiry dateJul 18, 1994

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B43/261
  • WIPO fieldBasic materials chemistry
  • WIPO sectorChemistry

Abstract

Aqueous gels suitable for plugging fractures in subterranean formations are produced by (1) thickening water by incorporating therein a thickening amount of a water-soluble cellulose ether (e.g.,CMC), (2) incorporating a water-soluble compound of a polyvalent metal (e.g., sodium or potassium dichromate) wherein the valence state of the metal therein is capable of being reduced to a lower polyvalent valence state, in an amount sufficient to cause gelation when the valence of at least a portion of said metal is reduced to said lower valence state, (3) incorporating a water-soluble reducing agent (e.g., a sulfite, hydrosulfite, metabisulfite or thiosulfate of sodium or potassium, sodium sulfide, hydrogen sulfide or mixtures thereof) in an amount effective to reduce at least a portion of said metal to said lower valence state and cause gelation, and (4) incorporating a finely divided solid (e.g., diatomaceous earth) in an amount sufficient to cause an increase in gel strength.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.