Methods for treating a well using a treatment fluid containing a water-soluble polysaccharide, a water-soluble salt, and urea
US7846877B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | May 20, 2009 |
| Grant date | Dec 7, 2010 |
| Priority date | — |
| Expiry date | Jul 2, 2029 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC09K2208/30
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Methods are provided for treating a portion of a well and include the steps of: (a) forming a treatment fluid comprising an aqueous solution, wherein the aqueous solution comprises: (i) water; (ii) a water-soluble polysaccharide; (iii) one or more water-soluble salts, wherein the one or more salts are selected and are in at least a sufficient concentration such that the water-salt solution has a density of at least 10 ppg; and (iv) urea; and (b) introducing the treatment fluid into the portion of the well. According to the inventions, the concentration of the urea in the water is in at least a sufficient concentration such that aqueous solution: (1) has a G′ of at least 2 Pa, or (2) is filterable. According to the inventions, an identical aqueous solution except with less than the sufficient concentration of the urea would not satisfy the above conditions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.