Water based fluids comprising multivalent salts and low molecular weight, low charge cationic polyacrylamide copolymers
US6855671B2 · kind B2 · utility
8Cited by
26References
95Claims
0Family size
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Key dates
| Filing date | Mar 11, 2002 |
| Grant date | Feb 15, 2005 |
| Priority date | — |
| Expiry date | May 23, 2022 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K2208/18
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
A drilling system fluid and method of using same. The drilling system fluid comprises water as a continuous phase, an amount of a multivalent metal, and a quantity of a water soluble polyacrylamide copolymer having a charge density of at least about 1%. In a preferred embodiment, the fluid also comprises a second amount of a monovalent salt effective to increase gas hydrate suppression and decrease density when compared to a fluid consisting essentially of only a divalent salt in the absence of the monovalent salt.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.