(257b) Experimental Studies Controlling Trace Components in a Dividing Wall Distillation Column

Melissa Donahue, Michael Baldea, R. Bruce Eldridge

McKetta Department of Chemical Engineering and

James R. Fair Process Science and Technology Center

The University of Texas at Austin

An example of one of the prominent technologies in the field of process intensification is dividing wall distillation columns or DWCs. As part of an ongoing experimental study of dividing wall columns at The University of Texas at Austin¹, the design and selection of control strategies for a pilot plant DWC will be presented. The pilot plant column is six inches in diameter and approximately 30 feet tall. The column has 24 theoretical stages of structured packing and a welded wall in the horizontal and vertical middle of the column¹. To investigate the operational flexibility of this fixed design DWC, a fourth trace component is added to the feed. A sensitivity analysis studying the minimum energy usage and optimal distribution of impurities is conducted using a dynamic process simulator. These operating targets and conventional distillation temperature control techniques are used to design control configurations that are then implemented on the pilot scale dividing wall column. The control configurations are tested against changes in set point and feed flow and composition disturbances.

(1) Blevins, T.; Downs, J. J.; Donahue, M. M.; Roach, B. J. Use Model Predictive Control to Achieve Real-Time Management of a DWC. Hydrocarbon Processing 2015.