Process for reducing production of biomass during activated sludge treatment of pulp and paper mill effluents
CA 2267690 C · Owner: Dorica, Joseph G. · Inventors: Elliott, Allan R.; Dorica, Joseph G.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process for reducing the production of biomass during activated sludge treatment of pulp and paper mill effluents involving a conditioning, of the recycled activated sludge (RAS) prior to its return into the aeration tank is described. The conditioning is typically performed within the sludge return line and involves RAS exposure to a waste acidic effluent originating from bleach plants of kraft sulphite mills or other mill sources.
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 March 31, 1999 and granted February 18, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended March 31, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by March 31, 2021.
- 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.