Method of treating shale and clay in hydrocarbon formation drilling
US5607902A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 4, 1996 |
| Grant date | Mar 4, 1997 |
| Priority date | — |
| Expiry date | Mar 4, 2016 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K8/607
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Swelling and migration of subterranean clay is inhibited during drilling for and stimulation of the production of hydrocarbon fluids, and preparation therefor, by treating said formations with a copolymer of about 5% to about 50% of an anionic monomer such as acrylic acid, methacrylic acid, or 2-acrylamido-2-methyl propane sulfonic acid and the balance a cationic monomer selected from dimethyl diallyl ammonium chloride, or acryloxy or methacryloxy ethyl, propyl or 3-methyl butyl trimethyl ammonium chlorides or methosulfates. Permeability damage to the formation is reduced in the presence of the copolymer; it is particularly effective in spite of the presence of a foaming agent.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.