Method and apparatus for continuously pulping cellulosic fibrous material
CA 2282065 A1 · Owner: Greenwood, Brian F. · Inventors: Greenwood, Brian F.; Stromberg, C. Bertil; Marcoccia, Bruno S.
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
In the production of chemical pulp, such as kraft pulp it is possible, to reduce the amount of ancillary equipment and/or the size of the, continuous digester vessel while achieving enhanced uniformity of treatment by avoiding "hang ups". Instead of providing vertical counter-current flow of liquid and comminuted cellulosic fibrous material being, treated in the lower half of the digester the counter-current flow may be a, cross flow that is substantially horizontal (e.g. radial) while the flow of the, chip column is vertical. Regardless of the configuration of the digester vessel, a single pump may be utilized for all of the recirculations or only a, few pumps for all of the …
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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 September 8, 1999. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended September 8, 2019.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by September 8, 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.