Method and apparatus for treating pulp in an indirect heat exchanger in connection with bleaching
CA 2225023 C · Owner: Andritz Oy · Inventors: Henricson, Kaj; Pikka, Olavi
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
The present invention relates to a method of treating pulp and an apparatus applying the method. The method and the apparatus according to the invention are especially suitable for the bleaching of medium consistency pulp when bleaching stages of various temperatures are used. It is characteristic of the invention to treat pulp in connection with chemical pulp manufacturing process in such a manner that pulp is allowed to flow prior to the bleaching reactor in the reactor itself, and/or thereafter at a rate of less than 5 m/s through an indirect heat exchanger, for changing the pulp temperature over 5 ~C preferably over 10 ~C.
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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
- Filed June 14, 1996 and granted January 28, 2003. A Canadian patent filed from October 1, 1989 lasts 20 years from filing, so its term ended June 14, 2016.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by June 14, 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.