(157d) Network of Dividing Wall Columns in a Grassroots Chemical Plant

When plot space is a critical limiting factor dictating the feasibility of a new, one-of-a-kind chemical plant, combining multiple columns into a single divided-wall-column does not stay only as an option, but becomes a necessity. In such cases, even one dividing wall column is not adequate, and companies need a series of inter-connected dividing wall columns (DWC’s) to minimize plot space requirements in order to be able to implement the new process.

Added to it, the complexities of multiple feed and operating cases, reactor recycle streams, presence of water and other trace impurities, and requirement of multiple high purity products – the challenge of implementing DWCs becomes many-fold. Of course, energy efficiency, equipment count reduction and utility savings are the obvious by-products of implementing the DWC’s.

The paper discusses the following:

1. Combining eight conventional columns into a series of four divided-wall-columns
2. Multiple instances of dual-divided-wall columns in the scheme.
3. Significant equipment count reduction
4. Energy savings of approx. 30%