Sand control agent and process
US5222557A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 19, 1991 |
| Grant date | Jun 29, 1993 |
| Priority date | — |
| Expiry date | Dec 19, 2011 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B43/04
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A method for forming a gravel pack in a washed-out interval is provided where a borehole penetrates an unconsolidated or loosely consolidated oil or gas reservoir which is likely to introduce substantial amounts of sand into the borehole. After perforating the boreholes's casing at a washed-out interval of the formation, sand is introduced into the interval. Afterwards, an aqueous silicate slug is injected into said interval. Next, a spacer volume of a water-immiscible hydrocarbonaceous liquid is introduced into the interval. Thereafter, a water-miscible organic solvent slug, containing an alkylpolysilicate and an inorganic or organic salt or a chelated calcium mixture, is injected into the interval. A permeability retaining silicate cement is formed in the interval thereby making a gravel pack. Injection of the aqueous silicate slug spacer volume and organic solvent EPS mixture are continued until the porosity of the interval has been reduced by the silicate cement to an extent sufficient to exclude formation fines and sand.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.