Method for scale removal in a wellbore
US5183112A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 16, 1991 |
| Grant date | Feb 2, 1993 |
| Priority date | — |
| Expiry date | Aug 16, 2011 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K8/528
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Alkaline earth metal scales, especially barium sulfate scale is removed from a well (the wellbore and the adjacent formation) by contacting the scale with a scale-removing solvent and thereafter sparging the solvent with air or insert gas to dissolve the scale. The sparging aids in achieving a flushing action by the solvent relative to the scale thereby enabling the solvent to more effectively dissolve the scale in the well. Temperature and caustic compatible surfactuants (anionic and non-ionic) may be used in the solvent to generate a column of foam which increases the extent of cleaning oil from the scale surfaces, enabling the solvent to more effectively remove the scale.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.