Rate-limiting Mechanisms of Water Removal during the Formation, Vacuum Dewatering, and Wet-pressing of Paper Webs: A Review
Because some of the critical events during the removal of water before the dryer section on a paper machine happen very rapidly within enclosed spaces – such as wet-press nips – there have been persistent challenges in understanding the governing mechanisms. In principle, a fuller understanding of t...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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North Carolina State University
2020-08-01
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| Series: | BioResources |
| Subjects: | |
| Online Access: | https://bioresources.cnr.ncsu.edu/resources/rate-limiting-mechanisms-of-water-removal-during-the-formation-vacuum-dewatering-and-wet-pressing-of-paper-webs-a-review/ |
| _version_ | 1797682041256411136 |
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| author | Martin A. Hubbe Björn Sjöstrand Lars Nilsson Antti Koponen J. David McDonald |
| author_facet | Martin A. Hubbe Björn Sjöstrand Lars Nilsson Antti Koponen J. David McDonald |
| author_sort | Martin A. Hubbe |
| collection | DOAJ |
| description | Because some of the critical events during the removal of water before the dryer section on a paper machine happen very rapidly within enclosed spaces – such as wet-press nips – there have been persistent challenges in understanding the governing mechanisms. In principle, a fuller understanding of the controlling mechanisms, based on evidence, should permit progress in achieving both higher rates of production of paper and more reliable control of paper attributes. In addition, energy can be saved, reducing environmental impacts. The goal of this article is to review published work dealing both with the concepts involved in water removal and evidence upon which existing and new theories can be based. The scope of this review includes all of the papermaking unit operations between the jet coming from the headbox and the final wet-press nip of an industrial-scale paper machine. Published findings support a hypothesis that dewatering rates can be decreased by densification of surface layers, plugging of drainage channels by fines, sealing effects, flocculation, and rewetting. Ways to overcome such effects are also reviewed. |
| first_indexed | 2024-03-11T23:53:45Z |
| format | Article |
| id | doaj.art-182a04e988fd4b6c9205651fea7e44f9 |
| institution | Directory Open Access Journal |
| issn | 1930-2126 |
| language | English |
| last_indexed | 2024-03-11T23:53:45Z |
| publishDate | 2020-08-01 |
| publisher | North Carolina State University |
| record_format | Article |
| series | BioResources |
| spelling | doaj.art-182a04e988fd4b6c9205651fea7e44f92023-09-18T19:56:58ZengNorth Carolina State UniversityBioResources1930-21262020-08-011549672975510.15376/biores.15.4.HubbeRate-limiting Mechanisms of Water Removal during the Formation, Vacuum Dewatering, and Wet-pressing of Paper Webs: A ReviewMartin A. Hubbe0Björn Sjöstrand1Lars Nilsson2Antti Koponen3J. David McDonald4Department of Forest Biomaterials, North Carolina State University, Campus Box 8005, Raleigh, NC 27695-8005Department of Engineering and Chemical Sciences, Karlstad University; Karlstad, SwedenDepartment of Engineering and Chemical Sciences, Karlstad University; Karlstad, SwedenVTT Tech. Res. Ctr. Finland Ltd, POB 1603, Jyväskylä 40401, FinlandJDMcD Consulting Inc., 97 rue Kerr, Vaudreuil-Dorion, Quebec, Canada J7V OG1Because some of the critical events during the removal of water before the dryer section on a paper machine happen very rapidly within enclosed spaces – such as wet-press nips – there have been persistent challenges in understanding the governing mechanisms. In principle, a fuller understanding of the controlling mechanisms, based on evidence, should permit progress in achieving both higher rates of production of paper and more reliable control of paper attributes. In addition, energy can be saved, reducing environmental impacts. The goal of this article is to review published work dealing both with the concepts involved in water removal and evidence upon which existing and new theories can be based. The scope of this review includes all of the papermaking unit operations between the jet coming from the headbox and the final wet-press nip of an industrial-scale paper machine. Published findings support a hypothesis that dewatering rates can be decreased by densification of surface layers, plugging of drainage channels by fines, sealing effects, flocculation, and rewetting. Ways to overcome such effects are also reviewed.https://bioresources.cnr.ncsu.edu/resources/rate-limiting-mechanisms-of-water-removal-during-the-formation-vacuum-dewatering-and-wet-pressing-of-paper-webs-a-review/drainage ratehydrofoilvacuum flatboxcouch rollpress feltextended-nip press |
| spellingShingle | Martin A. Hubbe Björn Sjöstrand Lars Nilsson Antti Koponen J. David McDonald Rate-limiting Mechanisms of Water Removal during the Formation, Vacuum Dewatering, and Wet-pressing of Paper Webs: A Review BioResources drainage rate hydrofoil vacuum flatbox couch roll press felt extended-nip press |
| title | Rate-limiting Mechanisms of Water Removal during the Formation, Vacuum Dewatering, and Wet-pressing of Paper Webs: A Review |
| title_full | Rate-limiting Mechanisms of Water Removal during the Formation, Vacuum Dewatering, and Wet-pressing of Paper Webs: A Review |
| title_fullStr | Rate-limiting Mechanisms of Water Removal during the Formation, Vacuum Dewatering, and Wet-pressing of Paper Webs: A Review |
| title_full_unstemmed | Rate-limiting Mechanisms of Water Removal during the Formation, Vacuum Dewatering, and Wet-pressing of Paper Webs: A Review |
| title_short | Rate-limiting Mechanisms of Water Removal during the Formation, Vacuum Dewatering, and Wet-pressing of Paper Webs: A Review |
| title_sort | rate limiting mechanisms of water removal during the formation vacuum dewatering and wet pressing of paper webs a review |
| topic | drainage rate hydrofoil vacuum flatbox couch roll press felt extended-nip press |
| url | https://bioresources.cnr.ncsu.edu/resources/rate-limiting-mechanisms-of-water-removal-during-the-formation-vacuum-dewatering-and-wet-pressing-of-paper-webs-a-review/ |
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