Treatment of water
CA 2047432 C · Owner: Clayton, John A. · Inventors: Clayton, John A.; Maree, Johannes P.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A water quality improvement process is provided for acid water containing sulphate and/or sulphite ions. The water is continuously fed into a fluidized bed containing calcium carbonate particles. The water consumes calcium carbonate and has its pH increased while calcium sulphate CaSO4 and/or CaSO3 are produced.
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 July 19, 1991 and granted November 20, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 19, 2011.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 19, 2013.
- 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.