Settable scavenger spacer fluid for displacing drilling mud
AssigneeSchlumberger Technology Corporation
InventorsRoderick Pernites, Xia Wei
Life of this patent
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Abstract
Described herein are settable spacer fluids and methods of making and using such fluids. The settable spacer fluids generally contain a polymerizable raw material and activator in aqueous medium, where the spacer fluid is configured to have density sufficient to displace fluids within a well and to solidify after a duration sufficient to allow use of the spacer fluid to aid in well development and placement of the spacer fluid at a target location prior to significant transformation. The spacer fluid solidifies over time, but can be used with final compressive strength as low as 50 psi.
Claims20
A method of treating a well, comprising:
- pumping a spacer fluid into the well, the spacer fluid comprising an aqueous medium, a polymerizable raw material, and an activator system that comprises 1) an activator and a release delay structure;
- or 2) an activator with a retardant reagent;
- or 3) an activator solution that gives the spacer fluid a pH of about 12 or less;
- displacing the spacer fluid to a target location within the well;
- and
- allowing the spacer fluid to solidify at the target location.
A method of treating a well, comprising:
- pumping a drilling fluid into a well;
- displacing the drilling fluid using a polymerizable spacer fluid having a density selected to displace the drilling fluid and having polymerization raw materials selected to provide a controlled polysialation reaction;
- displacing the polymerizable spacer fluid to a target location within the well;
- and
- allowing the spacer fluid to polymerize at the target location.
A spacer fluid for use in a well, the spacer fluid comprising:
- an aqueous medium comprising a polymerization mixture disposed in the aqueous medium, the aqueous medium having a pH less than about 12, the polymerization mixture having a controlled reaction rate in the aqueous medium that solidifies the spacer fluid after a predetermined time disposed in the aqueous medium.
Dependencies are inferred from the claim text.