Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

Experiments in a pilot-scale impulse unit - energy efficiencies

Larsson, H and Stenström, Stig LU (2001) In Nordic Pulp & Paper Research Journal 16(2). p.162-167
Abstract
Experiments were conducted to study the energy efficiency of the impulse unit in the pilot-scale research paper machine at the Swedish Pulp and Paper Research Institute (STFI) In Stockholm, Sweden. The paper produced was made of kraft softwood pulp with basis weights of 60-120 g/m(2). The roll surface temperature ranged from ambient temperature to 350 degreesC and the press loads were between 400-800 kN/m. The paper was produced at machine speeds: of 300-800 m/min. Two different impulse drying efficiencies were defined, the total specific energy use (TSEU) and the impulse drying specific energy use (ISEU). The TSEU was defined as the electrical power input divided by the total water removal. The TSEU should be used as an overall efficiency... (More)
Experiments were conducted to study the energy efficiency of the impulse unit in the pilot-scale research paper machine at the Swedish Pulp and Paper Research Institute (STFI) In Stockholm, Sweden. The paper produced was made of kraft softwood pulp with basis weights of 60-120 g/m(2). The roll surface temperature ranged from ambient temperature to 350 degreesC and the press loads were between 400-800 kN/m. The paper was produced at machine speeds: of 300-800 m/min. Two different impulse drying efficiencies were defined, the total specific energy use (TSEU) and the impulse drying specific energy use (ISEU). The TSEU was defined as the electrical power input divided by the total water removal. The TSEU should be used as an overall efficiency parameter and should be compared with existing dryer section efficiencies. The TSEU was mainly dependent on the roll surface temperature, the ingoing moisture ratio of the paper web, the press load and the basis weight. In general, the impulse unit had higher energy efficiency than a modern dryer section. The ISEU was defined as the power transferred to the paper web divided by the water removal due to the elevated temperature. This value should be compared with the latent heat of vaporisation and it provides information about the water removal mechanism in impulse drying. The ISEU was found to depend on the roll surface temperature and the ingoing moisture ratio of the paper web. The ISEU was close to the latent heat of vaporisation indicating that the water removal mechanism in impulse drying was hot pressing combined with flashing of superheated water. (Less)
Please use this url to cite or link to this publication:
author
and
organization
publishing date
type
Contribution to journal
publication status
published
subject
keywords
paper making, impulse drying, specific energy use
in
Nordic Pulp & Paper Research Journal
volume
16
issue
2
pages
162 - 167
publisher
Arbor Publishing AB
external identifiers
  • wos:000169961000013
  • scopus:0034948049
ISSN
0283-2631
language
English
LU publication?
yes
id
3b97d27b-42cc-45e3-aed5-2ab26131db42 (old id 3913996)
date added to LUP
2016-04-01 17:04:25
date last changed
2023-10-31 18:31:21
@article{3b97d27b-42cc-45e3-aed5-2ab26131db42,
  abstract     = {{Experiments were conducted to study the energy efficiency of the impulse unit in the pilot-scale research paper machine at the Swedish Pulp and Paper Research Institute (STFI) In Stockholm, Sweden. The paper produced was made of kraft softwood pulp with basis weights of 60-120 g/m(2). The roll surface temperature ranged from ambient temperature to 350 degreesC and the press loads were between 400-800 kN/m. The paper was produced at machine speeds: of 300-800 m/min. Two different impulse drying efficiencies were defined, the total specific energy use (TSEU) and the impulse drying specific energy use (ISEU). The TSEU was defined as the electrical power input divided by the total water removal. The TSEU should be used as an overall efficiency parameter and should be compared with existing dryer section efficiencies. The TSEU was mainly dependent on the roll surface temperature, the ingoing moisture ratio of the paper web, the press load and the basis weight. In general, the impulse unit had higher energy efficiency than a modern dryer section. The ISEU was defined as the power transferred to the paper web divided by the water removal due to the elevated temperature. This value should be compared with the latent heat of vaporisation and it provides information about the water removal mechanism in impulse drying. The ISEU was found to depend on the roll surface temperature and the ingoing moisture ratio of the paper web. The ISEU was close to the latent heat of vaporisation indicating that the water removal mechanism in impulse drying was hot pressing combined with flashing of superheated water.}},
  author       = {{Larsson, H and Stenström, Stig}},
  issn         = {{0283-2631}},
  keywords     = {{paper making; impulse drying; specific energy use}},
  language     = {{eng}},
  number       = {{2}},
  pages        = {{162--167}},
  publisher    = {{Arbor Publishing AB}},
  series       = {{Nordic Pulp & Paper Research Journal}},
  title        = {{Experiments in a pilot-scale impulse unit - energy efficiencies}},
  volume       = {{16}},
  year         = {{2001}},
}