Magnesia stabilized additives for non-clay wellbore fluids
Abstract
Abstract The additives are employed in non-clay wellbore fluids, as for example, in clear water, brines or emulsions used for drilling, well completion, workover, fracturing, and such stimulation operations as diverting injected flood fluids and acids or solvents. The basic additive may be a single organic material added primarily as a hydroxyalkyl cellulose viscosifier, hydroxyethyl cellulose (HEC) for example, stabilized with magnesia. Other conventional additives include natural gums, artificial gums, cellulose derivatives such as polyanionic cellulose polymers and anionic heteropolysaccharides, and pseudoplasticity-imparting gums and polymers such as hydrolyzed polyamides, lignosulfonate salts, same being used primarily for control of either viscosity or fluid loss, although such may have some controlling effect on both quantities. In general the magnesia stabilizer causes the viscosifier basic additive to act more quickly in absorbing water to thicken the wellbore fluid. It also will stabilize the thickened fluid at elevated temperatures and over a longer period than can be done by the basic additive alone. For those basic additives having fluid loss control properties the stabilizer simply tends to reduce the fluid lost to the formation over any given period of time.
Inventors
- 👤 Jack M. Jackson
Bibliographic Details
Claims Analysis
Total Claims: 6References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1979-04-27 | 1979-10-27 | 1980-04-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-04-27 | 1983-10-27 | 1984-04-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-04-27 | 1987-10-27 | 1988-04-27 | $7700.00 | Window Closed / Lapsed |