Process and apparatus for treatment of sewage sludge
CA 2199382 C · Owner: Rdp Company · Inventors: Christy, Paul G.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process and apparatus for treating sewage sludge having the steps of providing sludge at a desired rate from a sludge storage and feed hopper (22) to a conveyance means (20), mixing the sludge with at least one alkaline additive from storage silo (30) at a proportionate rate to the sludge to raise the pH of the mixture to at least a desired level in a conveying and mixing vessel (40), providing a pasteurization chamber (50) having a means to heat the contents of the chamber, continuously delivering the sludge and alkaline additive mixture to the inlet opening (52) of the pasteurization chamber (50) to maintain a minimum temperature of the sludge and alkaline additive mixture in …
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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 September 6, 1995 and granted February 20, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended September 6, 2015.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 6, 2017.
- 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.