Pulping process without a recovery furnace
CA 2345394 A1 · Owner: Kurple, Kenneth R. (Deceased) · Inventors: Kurple, Kenneth R. (Deceased)
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A novel pulping process has been discovered whereby acid is added to the black liquor mixture. The acid renders the lignin insoluble thus enabling it to be separated from the black liquor. The invention obviates the need for a recovery boiler which burns the sugars and the lignin. Additionally sodium , salts are precipitated out of the process. Sodium carbonate from outside sources is used in the novel process.
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 September 24, 1999. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 24, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 24, 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.