PRESSURE SWING WITH HEAT INTEGRATION

Design and Control of Distillation Systems for Separating Azeotropes. By William L. Luyben and I-Lung Chien Copyright 2010 John Wiley Sons, Inc. 

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Pressure Swing Extractive Pressure Swing with Heat Integration Extractive with Heat Integration... 

PRESSURE SWING WITH HEAT INTEGRATION Non heat integrated +20/-20 feed... 

PRESSURE SWING WITH HEAT INTEGRATION (a) Comparison with heat integration +20% feed rate... 

Figure 6.31 (a) Comparison of extractive and pressure-swing distillation with heat integration feed... 

Chemical-looping modifications of these processes open novel possibilities to address some of the main concerns associated with each of these processes as discussed below. The earliest CLR studies simply explored integration of CLC with a conventional reforming process [78,91-93]. For example, Ryden et al. [78] integrated the cran-bustion of the pressure-swing off-gas of a conventional SRM process to serve as the fuel for a CLC reducer reactor. This allows the capture of any carbon that was not cmiverted to CO in the reforming process itself via CO2 capture in the CLC step while providing some of the heat necessary for the endothermic reaction in the steam reformer. 

Knapp and Doherty studied heat-integration of binary homogeneous azeotropic systems using extractive distillation methods. One of their examples considered the acetone-methanol system with water as the solvent. They did not consider pressure-swing distillation, nor did they consider dynamics and control. 

The effectiveness of this control structure on the heat-integrated extractive distillation system is compared with that of the partially heat-integrated pressure-swing distillation system discussed in Chapter 6 in Figure 11.14. The controllability is quite similar. 

In this chapter, the use of extractive distillation has been illustrated using the acetone-methanol system as a numerical example. Steady-state and dynamic comparisons have been presented between extractive distillation and a pressure-swing distillation, with and without heat integration. In addition, the effect of solvent selection on dynamic controllability has been investigated. 

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