Modelling of Packaging Processes
for Brown Coal Briquettes
Description of the plant
At the Schwarze Pumpe Briquette Works of
the Lusatian Brown Coal Corporation (LAUBAG) new plants have been set up
for the packaging of briquettes in the sizes offered, i.e. 25 kg-bundles,
10 kg-bags and 10 kg-foil packs.
The running-in period of these new plants
was accompanied, as anticipated, by outages in the early stages and by
necessary modifications during current production, which either individually
or as a whole resulted in reduced performance as far as the target of 85%
bundle output was concerned.
Because of the complex nature of the technical
production and automation processes it was imperative to evolve stabilizing
measures and also to seek new methods of plant operation and throughput
that would effectively do away with interruptions and active experiments
during current production and could nevertheless be used to check the necessary
production sections and could be applied to the new plants.
As a means of representing the production
lines of pressing and bundling the method of modelling and simulation was
preferred, and this was developed by the Chair of Numerical and Applied
Mathematics at the Brandenburg Technical University of Cottbus, in close
collaboration with the LAUBAG, and was realized on SUN workstations (operating
system UNIX).
Models were completed for the briquette
press with integrated control, for the entire 25 kg-bundle packaging line
and the production line for the 10 kg-foil packs. By modelling and simulation
of the pressing section it could be ascertained that concerning the control
effectiveness the preset parameter combinations for the briquette thickness
controls of the presse lie in the optimum range. Alternative modern types
of control produce no improvements as compared to the three-point briquette
thickness control. The model developed for the reference value setting
by the application of numeric optimization processes has revealed reserve
capacity potentials in the case of the briquette presses.
Results
Simulation of the 25 kg-bundle packaging
line, on the one hand, proved the capacity of the transport lines under
full load, but, on the other hand, also draw attention to weak points.
It was ascertained that the use of the briquette-layer weight control can
definitely reduce the performance of the automatic bundling devices and
for this reason should continue to remain switched off. It will be used
again in future when the reference value setting has been changed. An optimum
distribution of the streams of bundles in front of the two palettizers
can prevent pile-ups. An analysis of the packaging and transport sequences
led to suggestions for improvements to the 10 kg-foil pack production line.
The purpose of the facts presented here
on the modelling and simulation of partial processes of briquette production
and packaging was to show how findings that are effective in actual practice
and economic advantages can be achieved by close collaboration between
a university and an industry and by co-ordinating basic scientific and
technical work with the application of the results on the production process.
A detailed description of the application
can be gathered from the following publications
-
Biedermann, J., Cromme, L., Rhede, L. , Weber,
K. und Würll, S. Simulation and Optimization of a Production Process
in Brown Coal Industry. Proceedings of the 15th IMACS World Congress
on Scientific Computation, Modelling and Applied Mathematics (IMACS
1997). Volume 5 - Systems Engineering, pages 707-712.
-
Würll, S., Biedermann, J., Cromme, L.
und Weber, K. Optimization of Quality Checks in a Fully Automated Production
Process. Proceedings of the 15th IMACS World Congress on Scientific
Computation, Modelling and Applied Mathematics (IMACS 1997). Volume
5 - Systems Engineering, pages 713-718.
-
Biedermann, J., Cromme, L., Rhede, L. , Rhen,
F., Weber, K. und Würll, S. Modellierung von Verpackungsprozessen
für Braunkohlenbriketts. Braunkohle - Surface Mining, 49. Jahrgang,
Nr. 4, Juli/August 1997
-
Cromme, L., Biedermann, J. and Würll,
S.: "Process Optimisation in the Packaging Industry of the Energy Industry:
optimisation of Weight Limits" In B. Scholz-Reiter, H.-D. Stahlmann, and
A. Nethe, editors, Process Modelling, pages 383-406, 1999, Springer
Further publications for this (in german):
-
Biegel, A.: Damit Top-Brikettbündel
die Fabrik verlassen; LAUBAG report Nr. 1, 8. Jahrgang 1997, S. 9.
-
Rhede, L.: Früher per Hand, jetzt elektronisch
geregelt; LAUBAG report Nr. 3, 8. Jahrgang 1997, S. 4.
-
Rhede, L.: Die Brikettdicke muß doch
zu regeln sein!; LAUBAG report Nr. 2, 8. Jahrgang 1997, S. 7.
-
Cromme, L., Biedermann, J., Weber, K. und
Würll, S.: Pressenmodell und Optimierung der Dreipunktregelung; Abschlußbericht
zur Teilleistung 1 des Pressenprojektes, Cottbus, Mai 1996.
-
Cromme, L., Biedermann, J., Weber, K. und
Würll, S.: Betrachtungen zu Erweiterungen der Pressenmodellierung
und zu anderen Reglertypen; Abschlußbericht zur Teilleistung 2 des
Pressenprojektes, Cottbus, Dezember 1996.
Publications to this and other fields
of research can be found at the papers
& preprints page.
Co-operation: Lausitzer
Braunkohle AG
Contact: Prof. Dr. rer. nat.
habil. Ludwig J. Cromme
Dipl.-Math.
Jochen Biedermann,
Dipl.-Math.
techn. Klaus Weber,
Dipl.-Math.
Stephan Würll