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Chemical Papers

, Volume 64, Issue 4, pp 450–460 | Cite as

Comparative evaluation of critical operating conditions for a tubular catalytic reactor using thermal sensitivity and loss-of-stability criteria

  • Gheorghe MariaEmail author
  • Dragoş-Nicolae Ştefan
Original Paper

Abstract

Optimal operation of a chemical reactor according to various performance criteria often drives the system towards critical boundaries. Thus, precise evaluation of runaway limits in the parametric space becomes a crucial problem not only for the reactor’s safe operation, but also for over-designing the system. However, obtaining an accurate estimate for operating limits is a difficult task due to the limited validity of kinetic models describing complex processes, as well as the inherent fluctuations of the system’s properties (catalyst, raw-material quality). This paper presents a comparison of several effective methods of deriving critical conditions for the case of a tubular fixed-bed catalytic reactor used for aniline production in the vapour phase. Even though the methods being compared are related to one another, the generalised sensitivity criterion of Morbidelli-Varma (MV) seems to be more robust, not depending on a particular parameter being perturbed, when compared to the criteria that detect an incipient loss of system stability in the critical region (i.e., div-methods based on the system’s Jacobian and Green’s function matrix analysis). Combined application of div- and MV criteria allows for an accurate evaluation of the distance from the reactor’s nominal conditions to the safety limits.

Keywords

runaway boundaries tubular reactor aniline sensitivity stability 

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Copyright information

© Institute of Chemistry, Slovak Academy of Sciences 2010

Authors and Affiliations

  1. 1.Department of Chemical EngineeringUniversity Politehnica of BucharestBucharestRomania

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