Stabilized fracture fluid and crosslinker therefor
AssigneeDowell Schlumberger Incorporated
InventorsSandra E. Baranet, Richard M. Hodge, Clare H. Kucera
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Abstract
Various organometallic crosslinkers containing titanium or zirconium atoms in the +4 oxidation (valence) state have been used to crosslink solvatable polysaccharides (e.g., hydroxypropyl guar) in aqueous media. The crosslinked gels are useful as fracturing fluids. Aqueous solutions of the organometallic crosslinkers are stabilized against deterioration upon storage by adding an alkanolamine (e.g., triethanolamine). Additionally, the alkanolamines also stabilize the crosslinked gels against shear degradation at elevated temperatures.
Claims17
A composition adapted to crosslink a solvatable polysaccharide in an aqueous media at a basic pH, said composition comprising an aqueous solution of (a) a crosslinking amount of an organometallic compound of zirconium in a +4 valence state and (b) a stabilizing amount of an alkanolamine corresponding to the formula
- R--N--(CH.sub.2 --CH(OH)--R').sub.2
- wherein
- R is H or CH.sub.2 --CH(OH)--R' and
- R' is H, --CH.sub.3 or --C.sub.2 H.sub.5,
- the molar ratio of said alkanolamine to said zirconium crosslinker being at least about 15.
Dependencies are inferred from the claim text.