Model Predictive Control of Reactive Dividing Wall Column for the Selective Hydrogenation and Separation of a C3 Stream in an Ethylene Plant

Abstract

The dividing wall column (DWC) is a promising process intensification technology of distillation. Researchers have been investigating different control structures of different DWC configurations. However, little research has been done on the control, especially model predictive control, of reactive dividing wall columns (RDWCs). The RDWC process in this article combines a depropanizer, propylene distillation, and selective hydrogenation into a single unit. The process is strongly interactive, which makes it difficult to achieve good control performance with traditional decentralized control strategies using PI control. The focus of this article is to investigate the model predictive control (MPC) scheme and compare the dynamic MPC responses with PI control. The dynamic responses of MPC are better than those of PI control. The maximum deviations are reduced, the oscillations are decreased, and the required settling times are smaller.