US Patent No: 5,238,065
Number of patents in Portfolio can not be more than 2000
Process and composition to enhance removal of polymer-containing filter cakes from wellbores
Stats
-
Aug 24, 1993
Issued date -
Jul 13, 1992
filing date -
07/912,282
serial no -
In Force
status
Importance
Loading Importance Indicators...
Abstract
The invention provides a process for the removal of filter cakes containing one or more polysaccharide polymers and bridging particles from the sides of a borehole in a hydrocarbon-producing formation which comprises contacting the filter cake with a novel soak solution comprising an aqueous liquid, a peroxide selected from the group consisting of alkaline earth metal peroxides, zinc peroxide, and mixtures thereof, and an acidic substance to provide the soak solution with a pH in the range from about 1 to about 8, and optionally, an activator for the peroxide, for a period of time at least sufficient to decompose the polysaccharide polymers therein to such an extent that the filter cake forms a loosely adherent mass on the sides of the borehole, and thereafter contacting the filter cake with a wash solution in which the bridging particles are soluble to remove the remaining filter cake solids from the sides of the borehole. Preferably the aqueous liquid in the soak solution has no appreciable solubilizing effect on the bridging particles.
Loading the Abstract Image...
First Claim
Related Publications
Loading Related Publications...
International Classification(s)
- [Classification Symbol]
- [Patents Count]
Cited Art
| Patent Info | (Count) | # Cites | Year |
|---|---|---|---|
|
|
|||
| 4,369,843 Well completion and work over method | 30 | 1978 | |
| 4,620,596 Well drilling, workover and completion fluids | 25 | 1984 | |
|
|
|||
| 4,440,651 Use of peroxide in waterflood oil recovery | 7 | 1981 | |
|
|
|||
| 4,609,475 Method of improving the permeability of a subterranean formation by removal of polymeric materials therefrom | 25 | 1984 | |