Method for treating wellbore in a subterranean formation with high density brines and complexed metal crosslinkers

摘要

The invention discloses a method of treating a wellbore by providing an aqueous mixture of a hydrated polysaccharide with a salt; adding to the mixture a cross-linking agent for cross-linking the hydrated polysaccharide, wherein the cross-linking agent comprises a zirconium compound, glutamic acid, and a polyol; pumping the aqueous mixture of the hydrated polysaccharide and the cross-linking agent into the wellbore; and cross-linking the hydrated polysaccharide.

主权项

1. A method comprising:
(a) providing an aqueous mixture of a hydrated polysaccharide with a salt; (b) adding to the mixture a cross-linking agent for cross-linking the hydrated polysaccharide, wherein the cross-linking agent is added as a complex comprising a zirconium compound, glutamic acid, and a polyol, and whereby the complex of zirconium compound, glutamic acid, and polyol provides delayed crosslinking of the zirconium compound with the polysaccharide; (c) pumping the aqueous mixture of the hydrated polysaccharide and the cross-linking agent into a wellbore; and (d) cross-linking the hydrated polysaccharide.