Conference article

Intelligent Modelling of a Fluidised bed Granulator Used in Production of Pharmaceuticals

Esko K. Juuso
Control Engineering Laboratory, Department of Process and Environmental Engineering, University of Oulu

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Published in: The 48th Scandinavian Conference on Simulation and Modeling (SIMS 2007); 30-31 October; 2007; Göteborg (Särö)

Linköping Electronic Conference Proceedings 27:12, p. 101-108

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Published: 2007-12-21


ISSN: 1650-3686 (print), 1650-3740 (online)


The aim of dynamic modelling and simulation is to improve the control of the fluidised bed granulator. Modelling and simulation was done on the basis of data collected from several test campaigns. Several modelling methodologies have been compared in Matlab-Simulink environment. A solution based on dynamic linguistic equation models was chosen. The main input variables are humidity difference between incoming and outgoing air; temperature difference between inflowing air and granule and the rate of inflowing air. The final output is the estimated granule size but the overall models contains also dynamic models for temperature and humidity. The simulator combines several models which are specific to the operating conditions. According to the results; the spraying and drying processes included short-duration periods. Extension to fuzzy LE models provides useful information about uncertainties of the forecasted granulation results. The complexity of the models is increased only slightly with the new system based on the extension principle and fuzzy interval analysis.


Fluidised bed granulator; linguistic equations; dynamic modelling; fuzzy set systems


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