Leaching process
CA 2180622 C · Owner: Haggstrom, Kimona · Inventors: Hammer-Olsen, Roy; Landfors, Johan; Haggstrom, Kimona
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
An increasing problem with the pulping chemical recovery system is the presence of chloride and potassium in the recovery boiler. Chloride and potassium increase inter alia the stickiness of carryover deposits and dust particles to the recovery boiler tubes which accelerate fouling, corrosion and plugging of the recovery boiler. As the environmental legisla- tion becomes more stringent the degree of system closure increases. The present invention relates to a process by which the collected precipitator dust is leached at a temperature exceeding 50°C, for a residence time sufficient to get a chloride and potassium enriched leach solution and to remove at least a part of the content of metal …
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 5, 1996 and granted June 5, 2001. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended July 5, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 5, 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.