BATCH EXTRACTIVE DISTILLATION BED

Dussel and Stichlmair (1995), Ahmad and Barton (1996), Safrit and Westerberg (1997) discussed the theoretical aspects of the separation of azeotropic mixtures in conventional and non-conventional BED column configurations using simulation techniques. Refer to the original references for further details. 

Tran and Mujtaba (1997) and Mujtaba et al. (1997) highlighted the operating features and limitations of BED processes for close boiling and azeotropic mixtures. However, the works were limited to the separation of only one key component in the distillate without due regard to the recovery of solvent or the separation of other components in the feed mixture. 

Mujtaba (1999) considered the conventional configuration of BED processes for the separation of binary close boiling and azeotropic mixtures. Dynamic optimisation technique was used for quantitative assessment of the effectiveness of BED processes. Two distinct solvent feeding modes were considered and their implications on the optimisation problem formulation, solution and on the performance of BED processes were discussed. A general Multiperiod Dynamic Optimisation (MDO) problem formulation was presented to obtain optimal separation of all the components in the feed mixture and the recovery of solvent while maximising the overall profitability of the operation. 

Low and Sorensen (2002) and Low (2003) considered optimal operation of BED processes in CBD and MVC columns using azeotropic mixtures. They used profit as the measure to compare the performances of such columns. For a given separation task, an MVC column was found to be superior to a CBD column. However, for maximum profitability most of the initial feed needed to be charged in 

In this chapter some of the work reported by Mujtaba and co-workers in the published literature will be discussed and presented for conventional BED processes. 

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Figure 10.3. Batch Extractive Distillation (BED) Process. [Mujtaba, 1999] ...

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