(372c) Reactive Distillation: Analysis of the Topology of a Reactive Residue Curve Map for a Continuous Column

Mulopo, L. J., COMPS

In this paper we present a new topologically based approach to the analysis and synthesis of continuous countercurrent reactive distillation columns. We extend the definition of Tapp et. al, (2004) of a Column Section in continuous distillation to a Reactive Column Section (RCS) in a countercurrent reactive distillation column. A RCS is defined as a section of a countercurrent reactive distillation column in which there is no addition or removal of material or energy. We introduce the concept of a Reactive Residue Curve Map (RRCM) in which the profiles in the RRCM correspond to the liquid composition profiles in the RCS. By looking at the singular points in the RRCM, it is demonstrated that for a single chemical reaction with no net change in the total number of models, the bifurcation of the singular points depends on both the initial non reactive difference point as introduced by Hauan et. al, (2000) as well as the direction of the stoichiometric vector. These two vectors combine to define what we call the Pseudo Reactive Difference Point Composition. We show that there only certain feasible topologies of the RRCM and these depend only the position of the Pseudo Reactive Difference Point Composition. We look at a simple example where the VLE is ideal and show that we can classify regions of Pseudo Reactive Difference Point Compositions that result in similar topology of the RRCM. Thus by understanding the feasible topologies of the RRCM, one is able to identify profiles in the RRCM that are desirable and hence one is able to synthesis of a continuous counter current reactive distillation column by combining RCS that correspond to the desired profile in the RRCM. We believe that this is a very powerful tool for synthesis and analysis of these complex systems. References

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