Heteropolysaccharide preparation and use thereof as a mobility control agent in enhanced oil recovery
US5236046A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 18, 1991 |
| Grant date | Aug 17, 1993 |
| Priority date | — |
| Expiry date | Jan 18, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K8/905
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A variant strain of Agrobacter radiobacter has been found to produce a unique heteropolysaccharide containing D-galactose, D-glucose and pyruvic acid in approximate molar ratios of 2:15:2 in a seventeen member repeat unit having the structure shown below, wherein Glc represents D-glucose, Gal represents D-galactose and Pyr represents pyruvic acid, with the numerals indicating the positions of linkage in these ring structures. The heteropolysaccharide is useful in mobility control in oil reservoir formations, especially when crosslinked with trivalent metal cations (Cr.sup.3+, Al.sup.3+, Fe.sup.3+ or Ti.sup.3+) to form a gel which preferentially fills high permeability zones in such reservoirs. ##STR1##
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.