Improved energy efficiency in debottlenecking using a fully thermally coupled distillation column

Increasing the throughput of an existing distillation process has received considerable attention due to the higher market demand for products derived therefrom. However, this could create a bottleneck in the column. The main objective of this work is to systematically identify bottlenecks in distillation columns and propose a strategy related to dividing wall column (DWC) use for debottlenecking within the column, as well as for energy saving. To optimize the DWC, the internal recycle flow distribution around the dividing wall was investigated as a primary optimizing variable. Several cases were analyzed to show that use of the DWC is a promising method for debottlenecking, as well as investment cost and energy consumption saving. (C) 2011 Curtin University of Technology and John Wiley & Sons, Ltd.