Method for effective placement of a long life scale inhibitor
US5377758A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 3, 1993 |
| Grant date | Jan 3, 1995 |
| Priority date | — |
| Expiry date | May 3, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S166/902
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method for placement of a long life scale inhibitor into a formation where variable density scale inhibitors are utilized. A substantially low density non-reactive fluid is loaded into an interval of the formation to be treated. Afterwards, a high density first stage scale inhibitor is injected into the interval. Thereafter, a low density spacer fluid is injected into the interval being treated. Next, a second stage high density scale inhibitor having a density lower than the first stage inhibitor is injected into said interval. Subsequently, a low density spacer is injected into the interval. Volume increments are repeatedly injected with decreasing fluid densities until a desired zone has been treated. The entire treatment is then overflushed with an inert high density fluid. Use of this method allows even inhibitor distribution in intervals of a formation with permeability variations thereby preventing scale build-up.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.