Process and system for purification of waste water
CA 2179575 C · Owner: Nordenskjold, Reinhart Von · Inventors: Nordenskjold, Reinhart Von
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A process and a system for the purification of waste water in several successive stages includes a first stage for anaerobic treatment of the waste water a second stage for aerobic treatment of the waste water a third stage for clarification and sedimentation of the waste water with a sludge return and.an arrangement for controlling the residence time of the waste water in the anaerobic stage by varying the volume of the anaerobic stage.
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 June 20, 1996 and granted March 14, 2000. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 20, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 20, 2018.
- 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.