Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
New methods for evaluation of tissue creping and the importance of coating, paper and adhesion
Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences.
2013 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

The creping process and the conditions on the Yankee cylinder dryer are key factors in a tissue paper mill, and they therefore need to be kept under good control in order to maintain a high and uniform quality. To this end it would be valuable to be able to make on-line measurements of Yankee coating thickness as well as the crepe structure of the tissue paper. The adhesion of paper to the cylinder affects the creping process and more information about the parameters that affect the adhesion is therefore of interest. To perform trials on a full scale or in a pilot plant is very costly and laboratory creping equipment is therefore sought after in order to be able to measure the adhesion force.

The coating layer for use on the cylinder was analysed. It contained a large amount of carbohydrates and could not be considered transparent. The thickness of the coating layer was measured on a laboratory cylinder with a method based on fluorescence. An optical brightener was added to the coating chemicals and the coating layer was subjected to UV-radiation. The intensity of the light emitted by the optical brightener was measured and gave an indication of the thickness of the coating layer. The equipment has to be further investigated before it is possible to implement the new sensor on-line.

New creping equipment and an adhesion method were developed for use on a laboratory scale. The equipment can operate with different creping angles and the force needed to crepe the paper can be measured. The highest creping force was obtained for papers of high grammage, low dryness at adhesion, high drainability, high fines content and high hemicellulose content.

A more direct method is to analyse the structure of the produced paper. Measurements were made on a tissue paper with an optical fibre sensor while the paper was travelling at low speed. The collected signal was mathematically analysed and the characteristic wavelength was calculated for different paper samples. These values were close to the wavelengths measured with an off line method by a commercial crepe analyser.

Abstract [en]

Baksidestext

The creping process is the heart of tissue paper manufacture. To control the process better, on-line measurements of paper structure and coating thickness are sought after. The creping is highly dependent on the adhesion of the paper to the Yankee dryer. To be able to measure the adhesion, laboratory creping equipment was also required. Different pulp parameters affect the adhesion and some of them have been investigated in this work.

The coating on the Yankee cylinder consisted mainly of fiber fragments and could not be considered as transparent, which had to be considered when choosing a method to measure coating thickness. A method based on the light emitted from an optical brightener in the coating when subjected to UV-irradiation was used, but has to be further improved before it can be used on-line.

A new laboratory creping method was developed to determine the adhesion between paper and metal, and the force needed to scrape off the paper with a doctor blade was measured. The highest creping force was obtained for papers made of pulp with a high drainability, high fines content and high hemicellulose content.

An optical method using reflected light to measure crepe wavelength on-line was developed. The paper travelled under a sensor and the light collected was mathematically analyzed to determine the most common wavelength.

Place, publisher, year, edition, pages
Karlstad: Karlstads universitet, 2013. , 60 p.
Series
Karlstad University Studies, ISSN 1403-8099 ; 2013:47Karlstad University Studies, ISSN 1403-8099
Keyword [en]
tissue, creping, paper adhesion, Tissue paper, creping, paper adhesion, coating layer, adhesives, Yankee cylinder, crepe structure, wavelength measurements
National Category
Engineering and Technology
Research subject
Chemical Engineering
Identifiers
URN: urn:nbn:se:kau:diva-29317ISBN: 978-91-7063-525-0 (print)OAI: oai:DiVA.org:kau-29317DiVA: diva2:659283
Public defence
2013-12-13, Nyqvistsalen, Karlstads universitet, Karlstad, 10:15 (English)
Opponent
Supervisors
Available from: 2013-11-22 Created: 2013-10-07 Last updated: 2015-11-26Bibliographically approved
List of papers
1. Chemical and Morphological Analyses of the Tissue Yankee Coating
Open this publication in new window or tab >>Chemical and Morphological Analyses of the Tissue Yankee Coating
2009 (English)In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, Vol. 24, no 1, 52-59 p.Article in journal (Refereed) Published
National Category
Chemical Engineering
Research subject
Chemical Engineering
Identifiers
urn:nbn:se:kau:diva-3813 (URN)10.3183/NPPRJ-2009-24-01-p052-059 (DOI)
Available from: 2009-03-19 Created: 2009-03-19 Last updated: 2013-11-22Bibliographically approved
2. A Method of Measuring the Thickness of the Coating on a Dryer Cylinder
Open this publication in new window or tab >>A Method of Measuring the Thickness of the Coating on a Dryer Cylinder
2009 (English)In: Nordic Pulp & Paper Research Journal, ISSN 0283-2631, Vol. 24, no 3, 309-312 p.Article in journal (Refereed) Published
National Category
Chemical Engineering
Research subject
Chemical Engineering
Identifiers
urn:nbn:se:kau:diva-3814 (URN)10.3183/NPPRJ-2009-24-03-p309-312 (DOI)
Available from: 2009-03-19 Created: 2009-03-19 Last updated: 2013-11-22Bibliographically approved
3. Laboratory creping equipment
Open this publication in new window or tab >>Laboratory creping equipment
2014 (English)In: Journal of Adhesion Science and Technology, ISSN 0169-4243, E-ISSN 1568-5616, Vol. 28, no 6, 561-572 p.Article in journal (Refereed) Published
Abstract [en]

Tissue production is largely dependent on the creping process as creping influences the paper properties and thus the quality of the end product and the runnability of the tissue machine. The process is very complex and includes numerous variables affecting the adhesion, and ultimately the creping of the tissue paper. To perform experiments on a full scale machine, or even a pilot machine, is very costly, therefore a laboratory scale creping device is demanded, able to replicate conditions encountered on a tissue machine. In this paper new laboratory testing equipment is developed, whereby the adhesion between paper and metal surfaces (when scraping off the paper with configurations similar to the industrial process) can be studied. A new method to adhere paper to metal, used in the new laboratory creping equipment, is also developed. To evaluate the equipment, different creping angles were tested. The scraping tests show a trend in decreasing creping force for an increasing creping angle.

Place, publisher, year, edition, pages
Taylor & Francis, 2014
Keyword
adhesion, tissue paper, creping, testing, Yankee
National Category
Engineering and Technology Chemical Engineering
Research subject
Chemical Engineering
Identifiers
urn:nbn:se:kau:diva-29920 (URN)10.1080/01694243.2013.849843 (DOI)000328728200003 ()
Available from: 2013-10-30 Created: 2013-10-29 Last updated: 2017-12-06Bibliographically approved
4. Influence of Various Pulp Properties on the Adhesion Between Tissue Paper and Yankee Cylinder Surface
Open this publication in new window or tab >>Influence of Various Pulp Properties on the Adhesion Between Tissue Paper and Yankee Cylinder Surface
2014 (English)In: BioResources, ISSN 1930-2126, E-ISSN 1930-2126, Vol. 9, no 2, 2107-2114 p.Article, review/survey (Refereed) Published
Abstract [en]

The strength of the adhesion between the paper and the drying Yankee cylinder is of great importance with respect to the final properties of a tissue paper product. Therefore, the effects of a few potentially important pulp properties have been evaluated in laboratory experiments. Four highly different kraft pulps were used, and the adhesion strength was measured by means of the force required when scraping off a paper from a metal surface with a specifically designed knife mounted on a moving cart. The adhesion strength was observed to increase with increasing grammage and increasing degree of beating of the pulp. It was also found that pulpscontainingmore fines, or with higher hemicellulose content, gave rise to higher adhesion strength.

Place, publisher, year, edition, pages
North Carolina: North Carolina State University, 2014
Keyword
Adhesion beating; Creping force; Fines; Hemicellulose; Tissue paper
National Category
Chemical Sciences
Research subject
Chemical Engineering
Identifiers
urn:nbn:se:kau:diva-31620 (URN)000336960700022 ()
Available from: 2014-03-04 Created: 2014-03-04 Last updated: 2017-12-07Bibliographically approved
5. Experiments to Find On-line Measurements of the Structure of the Tissue Paper Surface
Open this publication in new window or tab >>Experiments to Find On-line Measurements of the Structure of the Tissue Paper Surface
(English)Article in journal (Refereed) Submitted
Abstract [en]

The structure of tissue paper has great influence on the quality of the resulting paper produced. One method of measuring the crepe wavelength on-line is sought in order to improve process control as well as to promote greater precision and uniform quality of the end product. In this study, a probe was used to read the surface of the paper whilst the paper travelled at a low speed. Light from a light emitting diode was emitted at a specific angle and collected at the corresponding reflecting angle, from the paper surface.

 

Focusing the lenses at 45º angle produced results matching closest to the expected wavelength, and such measurements were made on a numerous commercial papers to validate the method. The collected signal contains a lot of information from the surface of the paper and from reflected signals inside the paper. The signal was processed using a mathematical approach to extract the most common wavelengths for each paper. The measured wavelength was found to closely match measurements made with commercial off-line equipment. This new method has a good initial potential to work on-line, however further investigation regarding the effects of high speeds upon the sampling still has to be carried out. 

Keyword
tissue paper, creping, wavelength, non-destructive, measurement surface, signal processing
National Category
Engineering and Technology
Research subject
Physics; Chemical Engineering
Identifiers
urn:nbn:se:kau:diva-29925 (URN)
Available from: 2013-10-29 Created: 2013-10-29 Last updated: 2014-10-28Bibliographically approved

Open Access in DiVA

2013_47(2329 kB)5393 downloads
File information
File name FULLTEXT02.pdfFile size 2329 kBChecksum SHA-512
d06c233e6d75c26698a7ca8e683ae23ed80112d2e2f59feed81894364fd1e25896a5957dda9e03c3f637024eeb58d8d7c88e293bba5432bab24445a0ede79fad
Type fulltextMimetype application/pdf

Authority records BETA

Boudreau, Jonna

Search in DiVA

By author/editor
Boudreau, Jonna
By organisation
Department of Engineering and Chemical Sciences
Engineering and Technology

Search outside of DiVA

GoogleGoogle Scholar
Total: 5394 downloads
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 563 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf