Expansion of Operating Range of Dividing Wall Columns

Dividing wall column (DWC) is a well-known heat integrated distillation scheme that found wide range of applications in chemical and petrochemical industries. Significant energy and capital savings were reported due to the use of DWC. In some cases savings as high as 30% energy and capital were reported in comparison to conventional distillation schemes.

On the other hand, the application of DWC are restricted by several constraints. One of the constraints is requirement that the middle boiling component should constitute at least 30 % of feed for DWC to be efficient.

In this work we analyzed several ways to overcome this constraint that were reported in literature and suggest by the authors of the work. We found that application of non-adiabatic approach to DWC design significantly increase operating range of DWC and allowed to overcome the constraint on the middle boiler content in the feed.

The finding are illustrated by comparison of several distillation schemes for separation of hydrocarbon products in an industrial process.