Method of supporting fractures in geological formations and hydraulic fluid composition for same
CA 2071849 C · Owner: Weyerhaeuser Company · Inventors: Stephens, Robert Scott; Winslow, Alan R.; Penny, Glenn S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The addition of relatively small quantities of a bacterial cellulose to hydraulic fracturing fluids improves their rheological properties for hydraulic fracturing of geological formations. Proppant suspension is markedly improved and friction loss through well casings is significantly reduced, resulting in lower pumping energy requirements. Computer models also indicate that formation fractures will be propagated for greater distances as will the propped portion of the fracture. Normally only about 0.60-1.8 g of bacterial cellulose per liter of fracturing fluid is needed. A preferred bacterial cellulose is one made in agitated fermentors using mutation resistant strains of a bacterium …
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Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed December 11, 1990 and granted September 14, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 11, 2010.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 11, 2012.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.