Distillation sequencing dividing wall column

Distillation. There is a large inventory of boiling liquid, sometimes under pressure, in a distillation column, both in the base and held up in the column. If a sequence of columns is involved, then, as discussed in Chap. 5, the sequence can be chosen to minimize the inventory of hazardous material. If all materials are equally hazardous, then choosing the sequence that tends to minimize the flow rate of nonkey components also will tend to minimize the inventory. Use of the dividing-wall column shown in Fig. 5.17c will reduce considerably the inventory relative to two simple columns. Dividing-wall columns are inherently safer than conventional arrangements because they lower not only the inventory but also the number of items of equipment and hence lower the potential for leaks. 

Eirico, M., Tola, G., Rong, B.G. et al. (2009) Energy saving and capital cost evaluation in distillation column sequences with a divided wall column. Chemical Engineering Research and Design, 87, 1649-1657. 

Long, N.V.D. and Lee, M. (2014) Review of retrofitting distillation columns using thermally coupled distillation sequences and dividing wall columns to improve energy efficiency. Journal of Chemical Engineering of Japan, 47, 87-108. 

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