Accelerated sedimentation of sludge
CA 2006483 C · Owner: Alberta Research Council · Inventors: Harris, Philip; Toma, Petre
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process is provided for treating the sludge in the tailings pond of a plant which uses the hot water process for extracting bitumen from oil sand. A predetermined quantity of a cationic surfactant is added to the sludge and the mixture is retained for a predetermined time. The mixture is aerated to flocculate and float off the fines and the residual oil a, portion of which is removed. As a result the sedimentation of the sludge is thereby accelerated.
Read the whole patent
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 20, 1989 and granted January 19, 1999. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended December 20, 2009.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by December 20, 2011.
- 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.