Water softening process and apparatus
CA 2059419 C · Owner: Yeda Research And Development Co. Ltd. · Inventors: Kedem, Ora; Ben-Dror, Jonathan
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
Process and apparatus for softening hard water by precipitation of calcium carbonate. The hard water is rendered alkaline, e.g. by the addition of sodium hydroxide and is then contacted with a large excess of calcium carbonate crystals whose size does not exceed 100 microns whereby precipitation occurs within a short contact time of the order of 2-60 seconds. Upon separation of soft water from calcium carbonate the bulk of the latter is recirculated and excessive amounts are removed.
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 January 15, 1992 and granted September 22, 1998. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended January 15, 2012.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by January 15, 2014.
- 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.