Abstract
Adjusting the feed tray locations may result in significant energy savings for double feed reactive distillation columns. In the literature, composition-based control structures have been suggested for the internally heat integrated designs of ideal reactive distillation columns. This paper explores the effect of feed tray location on the controllability of ideal reactive distillation columns using temperature-based control structures. Two different types of two-temperature inferential control structures are considered. In the first structure, two fresh feed flow rates are manipulated to control the temperatures on two selected trays. In the second structure, the light fresh feed flow rate and the vapor boilup are manipulated. Alternative designs are created by moving the feed trays in and out of the reactive zone. It is demonstrated that significant energy savings are obtained by shifting the feed tray locations into the reactive zone. The results indicate that there are internally heat integrated designs, which can be effectively controlled by a two-temperature inferential control structure without using any direct composition measurement. For the case study examined, a 13.17% energy saving is obtained by shifting the fresh feed trays into the reactive zone by two trays from their conventional locations. The second temperature-based control structure considered can handle fairly large throughput changes without any system shut down or steady-state transition for this energy-efficient design.
Original language | English |
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Pages (from-to) | 11071-11080 |
Number of pages | 10 |
Journal | Industrial and Engineering Chemistry Research |
Volume | 48 |
Issue number | 24 |
DOIs | |
Publication status | Published - 2009 |