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Granulering - ett dynamiskt betraktelsesätt

Gabrielsson, Per and Luterkort, Staffan (1972) In MSc Theses
Department of Automatic Control
Abstract
In this work mathematical models of a granulating process plant have been determined. The plant is situated at the SUPRA company, Landskrona Sweden. The product studied is a fertilizer NPK. In the process there are oscillations in the material flow. The models will be used an attempt to explain and hopefully control the process better. <br><br> In the first stage it was tried to obtain a physical model of the granulator. It appears, however, that the measurement problems are so severe, that the unknown coefficients of the model could not be determined by measurements. <br><br> Later, parametric models for the granulator and the recirculation flow were derived. These models were combined to a closed system model for the whole process.... (More)
In this work mathematical models of a granulating process plant have been determined. The plant is situated at the SUPRA company, Landskrona Sweden. The product studied is a fertilizer NPK. In the process there are oscillations in the material flow. The models will be used an attempt to explain and hopefully control the process better. <br><br> In the first stage it was tried to obtain a physical model of the granulator. It appears, however, that the measurement problems are so severe, that the unknown coefficients of the model could not be determined by measurements. <br><br> Later, parametric models for the granulator and the recirculation flow were derived. These models were combined to a closed system model for the whole process. <br><br> One important problem is the stability due to the long transport delays. <br><br> From the Maximum Likelihood identifications it appeared, that grain size, and recirculation temperature are the major state variables. It was difficult to prove any influence on the dynamics from the granulator fan of the moisture content of the flow. This is of course not a general statement, but is valid for the product (NPK 8.6.18) of the present experiment. <br><br> The model accuracy is not satisfactory. This depends on the fact that only normal disturbances were used in the experiment and also that the number of samples is very small. It is, however, interesting to show that a relatively simple and short experiment can give dynamic models, that can explain the principal dynamic behaviour of the granulating plant. (Less)
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author
Gabrielsson, Per and Luterkort, Staffan
supervisor
organization
year
type
H3 - Professional qualifications (4 Years - )
subject
publication/series
MSc Theses
report number
TFRT-5119
ISSN
0346-5500
language
Swedish
id
8850596
date added to LUP
2016-03-29 15:58:17
date last changed
2016-03-29 15:58:17
@misc{8850596,
  abstract     = {In this work mathematical models of a granulating process plant have been determined. The plant is situated at the SUPRA company, Landskrona Sweden. The product studied is a fertilizer NPK. In the process there are oscillations in the material flow. The models will be used an attempt to explain and hopefully control the process better. <br><br> In the first stage it was tried to obtain a physical model of the granulator. It appears, however, that the measurement problems are so severe, that the unknown coefficients of the model could not be determined by measurements. <br><br> Later, parametric models for the granulator and the recirculation flow were derived. These models were combined to a closed system model for the whole process. <br><br> One important problem is the stability due to the long transport delays. <br><br> From the Maximum Likelihood identifications it appeared, that grain size, and recirculation temperature are the major state variables. It was difficult to prove any influence on the dynamics from the granulator fan of the moisture content of the flow. This is of course not a general statement, but is valid for the product (NPK 8.6.18) of the present experiment. <br><br> The model accuracy is not satisfactory. This depends on the fact that only normal disturbances were used in the experiment and also that the number of samples is very small. It is, however, interesting to show that a relatively simple and short experiment can give dynamic models, that can explain the principal dynamic behaviour of the granulating plant.},
  author       = {Gabrielsson, Per and Luterkort, Staffan},
  issn         = {0346-5500},
  language     = {swe},
  note         = {Student Paper},
  series       = {MSc Theses},
  title        = {Granulering - ett dynamiskt betraktelsesätt},
  year         = {1972},
}