Continuous digester with a low temperature gas-phase

Paper making and fiber liberation – Processes of chemical liberation – recovery or purification... – Gas – vapor or mist contact

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

162 66, 162 17, 162 19, 162 41, 162 47, 162 52, D21C 700, D21C 326

Patent

active

058824774

ABSTRACT:
A cellulose pulp continuous digester (e.g. for producing kraft pulp) is operated so that it has the advantages of a hydraulic digester yet has a gas-filled zone over the liquid level. A slurry of chips and cooking liquor is introduced into the top of the digester vessel through an inverted top separator. A liquid level is established below the inverted top separator, and a chips level is established below the inverted top separator (above or below the liquid level). A gas-filled zone above the liquid level includes compressed gas, and is at a temperature of less than 160 (preferably less than 120).degree.C. and at a pressure of between 50-200 (preferably 80-150) psig. The chips are heated by recirculating and heating liquid using a recirculation loop below the chips level, and a countercurrent flow zone is preferably provided.

REFERENCES:
patent: 3380883 (1968-04-01), Richter et al.
patent: 3429773 (1969-02-01), Richter
patent: 3532594 (1970-10-01), Richter
patent: 3578554 (1971-05-01), Richter
patent: 3802956 (1974-04-01), Backlund
patent: 4668340 (1987-05-01), Sherman
patent: 5053108 (1991-10-01), Richter
patent: 5236553 (1993-08-01), Richter
patent: 5413677 (1995-05-01), Collins
patent: 5536366 (1996-07-01), Marcoccia et al.
Annergren et al, "Neutral Sulfite Semichemical Pulping with Diffusion Washing in a Kamyr Digester", Tappi, The Journal of the Technical Association of the Pulp and Paper Industry, vol. 51, No. 5, May 1968.
"The History of Kamyr Continuous Cooking" by Johan Richter, 1981, pp. 48 through 51.
"Continuous Pulping Processes" by Sven Rydholm, Tappi Stap Series, 1970, lecture 9, pp. 121-157.
"Continuous Digesters" by Brian Greenwood, Kamyr, Inc., Apr., 1991, CPPA Tech '91 Kraft Pulping Course, pp. 2.1-2.14.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Continuous digester with a low temperature gas-phase does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Continuous digester with a low temperature gas-phase, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Continuous digester with a low temperature gas-phase will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-813758

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.