Displacement bleaching temperature control
CA 1095765 A · Owner: Kamyr, Inc. · Inventors: Gullichsen, Johan E.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A method of displacement bleaching digested washed, cellulosic pulp. Pulp is continuously passed through successive bleaching stages, each bleaching stage having a displacementextraction loop. Bleaching chemical is added to the pulp in each bleaching stage to effect bleaching. Minimization of chemical consumption within an oxidative displacement-extraction loop is important in displacement bleaching, and this is accomplished by controlling the reaction rate with temperature. The temperature in a given oxidative displacement-extraction loop (i.e. with Chlorine dioxide bleaching chemical) is maintained in the range of about 120°F to less than 160°F, preferably about 135 - 140°F. A 0.5% net …
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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
- Granted February 17, 1981. A Canadian patent filed before October 1, 1989 lasted 17 years from grant, so its term ended February 17, 1998.
- 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.