← Back to Patent Explorer
US3961639A Expired / Lapsed US ⏱️ 0.0 years remaining

Methods and compositions for reducing the frictional resistance to flow of aqueous liquids

Assignee: University of Missouri–St. Louis
•
Filing: 1973-09-10
•
Granted: 1976-06-08
•
Expires: 1993-09-10
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract The frictional energy losses in the flow of an aqueous liquid along a surface such as the inside wall of a pipe are reduced by incorporating a polyethylene oxide alcohol surfactant into the liquid, moving the liquid on a flow path along the surface and maintaining the temperature of the liquid near to or greater than its cloud point. The frictional energy loss per unit length of the flow path is thereby reduced below the corresponding loss of energy which occurs when moving pure water at the same volumetric rate on the same path. Optionally, an electrolyte or salt is included in the aqueous mixture to depress the cloud point thereof. Preferably, the surfactant employed contains between about 12 and 18 carbon atoms in its lipophilic moiety and between about 3 and about 9 ethylene oxide units in its hydrophilic moiety.

Inventors

  • 👤 Jen-Lin Chang
  • 👤 Jacques L. Zakin

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 21:35
CPC Classifications
F; F15; F15D; F15D1/00; F15D1/02; F15D1/06; F17; F17D; F17D1/00; F17D1/08; F17D1/16; F17D1/17; Y; Y10; Y10T; Y10T137/00; Y10T137/0318; Y10T137/0391

Claims Analysis

Total Claims: 11
Claim 1
Independent Claim 109 words
A method for reducing the frictional energy losses in the flow of an aqueous liquid along a surface comprising: incorporating into said liquid a polyethylene oxide alkyl alcohol surfactant; moving said liquid on a flow path along said surface at a velocity sufficient to provide a Reynolds number greater than about 4000 based on the properties of water; and maintaining the temperature of said liquid near to or greater than its cloud point, whereby the frictional energy loss per unit length of said flow path is less than the corresponding loss of energy which occurs when moving substantially pure water at the same volumetric rate on the same path.
Claim 2
Independent Claim 109 words
A method for reducing the frictional energy losses in the flow of an aqueous liquid along a surface comprising: incorporating into said liquid a polyethylene oxide alkyl alcohol surfactant; moving said liquid on a flow path along said surface at a velocity sufficient to provide a Reynolds number greater than about 4000 based on the properties of water; and maintaining the temperature of said liquid near to or greater than its cloud point, whereby the frictional energy loss per unit length of said flow path is less than the corresponding loss of energy which occurs when moving substantially pure water at the same volumetric rate on the same path.
Claim 3
Dependent Claim 22 words
A method as set forth in claim 1 wherein said polyethylene oxide alkyl alcohol comprises a polyethylene oxide straight chain alkyl alcohol.
Claim 4
Dependent Claim 41 words
A method as set forth in claim 1 wherein the lipophilic moiety of said surfactant contains between about 12 and about 18 carbon atoms and the hydrophilic moiety of said surfactant contains between about 3 and about 9 ethylene oxide units.
Claim 5
Dependent Claim 23 words
A method as set forth in claim 3 wherein said mixture contains between 0.2 and about 2 percent by weight of said surfactant.
Claim 6
Dependent Claim 24 words
A method as set forth in claim 4 wherein said mixture contains between about 0.5 and about 1 percent by weight of said surfactant.
Claim 7
Dependent Claim 38 words
A method as set forth in claim 1 wherein said mixture further comprises a salt which depresses the cloud point of the mixture, said salt being selected from the group consisting of inorganic metallic salts and metal acetates.
Claim 8
Dependent Claim 22 words
A method as set forth in claim 6 wherein the normality of said salt in said mixture is at least about 0.2.
Claim 9
Dependent Claim 57 words
A method as set forth in claim 7 wherein said salt is selected from the group consisting of sodium chloride, potassium chloride, sodium sulfate, sodium thiosulfate, potassium nitrate, sodium nitrate, potassium sulfate, potassium thiosulfate, potassium phosphate, ferric chloride, sodium persulfate, potassium persulfate, potassium ferrocyanide, potassium iodide, potassium pyrosulfate, sodium acetate, sodium tetraborate, calcium chloride and sodium phosphate.
Claim 10
Dependent Claim 34 words
A method as set forth in claim 1 wherein said surface is the inside surface of a closed conduit and said flow path extends between different points inside said conduit along the length thereof.
Claim 11
Dependent Claim 64 words
A method as set forth in claim 9 wherein said mixture contains between about 0.2 and about 2 percent by weight of a polyethylene oxide alkyl alcohol whose lipophilic moiety contains between about 12 and about 18 carbon atoms and whose hydrophilic moiety contains between about 3 and about 9 ethylene oxide units, and a salt at a normality of at least about 0.2.

References Cited (Backward Citations)

US2913417A Cited
US2533878A Cited
US3346047A Cited
US3361213A Cited
US3553130A Cited
US3472769A Cited
US3679608A Cited
US3736288A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-06-08 1979-12-08 1980-06-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-06-08 1983-12-08 1984-06-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-06-08 1987-12-08 1988-06-08 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag