Interpretation of force profiles in mill-scale LC refining
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Matthias Aigner
,
James Olson
Abstract
A set of piezo electric force sensors is implemented in a 52-inch mill-scale low consistency refiner to explore the effect of varying operating conditions on bar force profiles. The sensor replaces a short length of a stator bar and measures normal and shear forces applied during the passage of each rotor bar. In previous work with this type of force sensor a rotary encoder was used to investigate force profiles for individual bar passing events (BPE) on a 16-inch laboratory-scale refiner. In the work presented here, force profiles for individual BPEs are identified based on key features in the time domain force data. The individual bar force profiles are classified as single peak events which feature one peak corresponding to the fiber compression force and as dual peak events corresponding to fiber compression force and the corner force. The bar passing events are then analysed based on their mean force profiles and their dual peak ratio in the bar passing event. Findings are compared and validated by previous work on bar force profiles. It is shown that dual peak events which are considered to represent the corner force, are present through out the whole range of refining and increase with increased refining energy. This increases the understanding of the way corner force contributes to the refining process. Furthermore, it is found that different radial positions on the stator plate are subjected to different force profiles. This is thought to be due to the difference in tangential speed and a change in the fiber and floc material properties at different radial positions.
Funding source: Canadian Network for Research and Innovation in Machining Technology, Natural Sciences and Engineering Research Council of Canada
Award Identifier / Grant number: 11R1977
Funding statement: This work is funded by a Collaborative Research and Development Grant provided by the Natural Sciences and Engineering Research Council of Canada (NSERC, Grant No. 11R1977) and the following partners, who we thank for their ongoing support: AB Enzymes, Alberta Newsprint Company, Andritz, BC Hydro, Canfor, Catalyst Paper, FPInnovations, Holmen Paper, Meadow Lake Pulp (Paper Excellence), Millar Western, NORPAC, West Fraser, Westcan Engineering, and Winstone Pulp International.
Acknowledgments
The authors gratefully acknowledge the assistance of Chad Toth, Pat Cooper and their colleagues at the Catalyst Paper Excellence mill at Crofton BC during the preparation for and execution of the refining trials.
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Conflict of interest: The authors declare no conflicts of interest.
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© 2022 Walter de Gruyter GmbH, Berlin/Boston
Artikel in diesem Heft
- Frontmatter
- Chemical pulping
- Evaluation of fines separation from unbleached softwood kraft pulp using microperforated hole screens
- Evaluation of pulp and paper making properties of Caesalpinia decapetela
- Novel bulking technologies for cellulose fibres
- Mechanical pulping
- Interpretation of force profiles in mill-scale LC refining
- Effects of plate wear on bar forces and fiber properties in a mill scale LC-refiner
- Paper technology
- Research on the physical properties of calcium sulfate whisker and the effects of its addition on paper and its printing performance
- Preparation and properties of an intelligent adjustable functional paper for organic cultural relics
- Paper chemistry
- Application of DSA to improve strength of thermomechanical pulp blended paper
- Coating
- The influence of pigment modulus on failure resistance of paper barrier coatings
- Effect of filler additions on pilot-scale extrusion coating of paperboard with PLA-based blends
- Packaging
- Influence of paper properties on adhesive strength of starch gluing
- Environmental impact
- Interfering elements on determination of hexavalent chromium in paper materials with UV-vis spectrophotometry
- Nanotechnology
- Enhanced mechanical and gas barrier performance of plasticized cellulose nanofibril films
- Lignin
- The preparations of nanoporous carbon with multi-heteroatoms co-doping from black liquor powders for supercapacitors
- Miscellaneous
- Hybrid films from plant and bacterial nanocellulose: mechanical and barrier properties
- Mass-balance based soft sensor for monitoring ash content at two-ply paperboard manufacturing
- Investigation of the effect of light fastness on the color changes of maps prepared by electrophotographic digital printing
- Bulking of cellulose fibres – a review
- Preparation of O-HACC/HEC-acrylate emulsion and its application in paper protection
- Mineral-filled biopolyester coatings for paperboard packaging materials: barrier, sealability, convertability and biodegradability properties
Artikel in diesem Heft
- Frontmatter
- Chemical pulping
- Evaluation of fines separation from unbleached softwood kraft pulp using microperforated hole screens
- Evaluation of pulp and paper making properties of Caesalpinia decapetela
- Novel bulking technologies for cellulose fibres
- Mechanical pulping
- Interpretation of force profiles in mill-scale LC refining
- Effects of plate wear on bar forces and fiber properties in a mill scale LC-refiner
- Paper technology
- Research on the physical properties of calcium sulfate whisker and the effects of its addition on paper and its printing performance
- Preparation and properties of an intelligent adjustable functional paper for organic cultural relics
- Paper chemistry
- Application of DSA to improve strength of thermomechanical pulp blended paper
- Coating
- The influence of pigment modulus on failure resistance of paper barrier coatings
- Effect of filler additions on pilot-scale extrusion coating of paperboard with PLA-based blends
- Packaging
- Influence of paper properties on adhesive strength of starch gluing
- Environmental impact
- Interfering elements on determination of hexavalent chromium in paper materials with UV-vis spectrophotometry
- Nanotechnology
- Enhanced mechanical and gas barrier performance of plasticized cellulose nanofibril films
- Lignin
- The preparations of nanoporous carbon with multi-heteroatoms co-doping from black liquor powders for supercapacitors
- Miscellaneous
- Hybrid films from plant and bacterial nanocellulose: mechanical and barrier properties
- Mass-balance based soft sensor for monitoring ash content at two-ply paperboard manufacturing
- Investigation of the effect of light fastness on the color changes of maps prepared by electrophotographic digital printing
- Bulking of cellulose fibres – a review
- Preparation of O-HACC/HEC-acrylate emulsion and its application in paper protection
- Mineral-filled biopolyester coatings for paperboard packaging materials: barrier, sealability, convertability and biodegradability properties
