“Catalytic cracking models developed for predictive control purposes”

Authors: Dag Ljungquist, Stig Strand and Jens G. Balchen,
Affiliation: Norsk Hydro, SINTEF and NTNU, Department of Engineering Cybernetics
Reference: 1993, Vol 14, No 2, pp. 73-84.

Keywords: State-space methods, catalytic cracking, predictive control, modeling, model validation

Abstract: The paper deals with state-space modeling issues in the context of model-predictive control, with application to catalytic cracking. Emphasis is placed on model establishment, verification and online adjustment. Both the Fluid Catalytic Cracking (FCC) and the Residual Catalytic Cracking (RCC) units are discussed. Catalytic cracking units involve complex interactive processes which are difficult to operate and control in an economically optimal way. The strong nonlinearities of the FCC process mean that the control calculation should be based on a nonlinear model with the relevant constraints included. However, the model can be simple compared to the complexity of the catalytic cracking plant. Model validity is ensured by a robust online model adjustment strategy. Model-predictive control schemes based on linear convolution models have been successfully applied to the supervisory dynamic control of catalytic cracking units, and the control can be further improved by the SSPC scheme.

PDF PDF (1718 Kb)        DOI: 10.4173/mic.1993.2.2

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  title={{Catalytic cracking models developed for predictive control purposes}},
  author={Ljungquist, Dag and Strand, Stig and Balchen, Jens G.},
  journal={Modeling, Identification and Control},
  publisher={Norwegian Society of Automatic Control}