Abstract:
A process that includes pumping a first wellbore fluid comprising an oxidative degradable polymer into a wellbore through a subterranean formation; pumping a second wellbore fluid comprising a pH-activated oxidative breaker into the wellbore; pumping a third wellbore fluid comprising a delayed acid source into the wellbore; and allowing the delayed acid source to acidify at least a portion of the wellbore to a pH of less than 7 so as to activate the pH-activated oxidative breaker at the lower pH and degrade the oxidative degradable polymers is disclosed.
Abstract:
A wellbore fluid that includes an aqueous based fluid; an amphoteric, viscoelastic surfactant; and a modified starch is disclosed. Methods of drilling subterranean wells, methods of reducing the loss of fluid out of subterranean wells, and methods of completing wellbores using aqueous-based fluids having an ampoteric, viscoelastic surfactant and a modified starch are also disclosed.
Abstract:
A breaker fluid for breaking a filtercake in a wellbore. The fluid including a hydrolysable ester of carboxylic acid, and a chelant, an alkyl glycoside, or a combination thereof. The breaker fluid may be pre-mixed and include an amount of water less than required to completely hydrolyze the ester.
Abstract:
A breaker fluid for breaking a filtercake in a wellbore. The fluid including a hydrolysable ester of carboxylic acid, and a chelant, an alkyl glycoside, or a combination thereof. The breaker fluid may be pre-mixed and include an amount of water less than required to completely hydrolyze the ester.
Abstract:
A process that includes pumping a first wellbore fluid comprising an oxidative degradable polymer into a wellbore through a subterranean formation; pumping a second wellbore fluid comprising a pH-activated oxidative breaker into the wellbore; pumping a third wellbore fluid comprising a delayed acid source into the wellbore; and allowing the delayed acid source to acidify at least a portion of the wellbore to a pH of less than 7 so as to activate the pH-activated oxidative breaker at the lower pH and degrade the oxidative degradable polymers is disclosed.
Abstract:
A method of retarding the flow of water in a subterranean formation that includes injecting a gelling pill into the formation, the gelling pill comprising: brine; a crosslinkable polymer; and a crosslinkant; and allowing the crosslinkable polymer to crosslink to form a gel in the subterranean formation is disclosed. A water absorbing polymer is optionally included.
Abstract:
A wellbore fluid that includes an aqueous based fluid; an amphoteric, viscoelastic surfactant; and a modified starch is disclosed. Methods of drilling subterranean wells, methods of reducing the loss of fluid out of subterranean wells, and methods of completing wellbores using aqueous-based fluids having an ampoteric, viscoelastic surfactant and a modified starch are also disclosed.