TY - JOUR A1 - Löwe, Katharina A1 - Li, Pu A1 - Wozny, G. T1 - Development and Experimental Verification of a Time-optimal Startup Strategy for a High Purity Distillation Column JF - Chemical Engineering and Technology : CET 23 (2000) 10 N2 - Flexible startup, shutdown and product changeover procedures are necessary in today's chemical industry. The startup of chemical processes, such as distillation, represents one of the most complicated procedures in industrial practice. The computational and experimental results show that the optimal control policies can improve the operation performance with time saving of up to 45 %. This allows a significant reduction of energy and raw material consumption also and consequently can lead to a more economical process. Y1 - 2000 SN - 0930-7516 (print) SN - 1521-4125 (online) SP - 841 EP - 845 ER - TY - CHAP A1 - Löwe, Katharina A1 - Wozny, G. A1 - Gelbe, H. T1 - Startup of Heat- and Mass- Integrated Distillation Colurnns : an experimental study T2 - Proceedings / 2nd Conference on Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction : May 31 - June 2, 1999, Budapest, Hungary / PRES '99. Eds.: F. Friedler ... Y1 - 1999 SN - 963-8192-87-9 SP - 415 EP - 420 PB - Hungarian Chemical Society CY - Budapest ER - TY - JOUR A1 - Löwe, Katharina A1 - Wozny, G. T1 - A new strategy for product switchover and startup for a heat- and mass-integrated distillation system JF - Chemical Engineering and Processing: Process Intensification 40 (2001) 3 N2 - For most separations fully thermally coupled distillation columns are thermodynamically more efficient than conventional arrangements. In spite of the superiority of double-effect distillation systems to a single column concerning energy savings these systems are not often used in the industrial practice, because of the disadvantages in dynamic operability. Generally the product switchover is a complicated and protracted operation, where many process variables must be changed simultaneously. The economic and ecological interest is to minimize the time of switchover periods, which are generally non-productive and require long times especially for coupled systems. The aim of this study is to reduce the time needed for the product switchover of coupled distillation systems. This paper presents a new product switchover strategy, which will lead to a time saving of 57%. Furthermore, a new startup strategy is developed and verified in experimental studies. The results demonstrate that using the optimized startup strategy a time saving of 57% can be achieved too and thereby these unproductive periods can be reduced significantly. Copyright © 2001 Elsevier Science B.V. Y1 - 2001 SN - 0255-2701 SP - 295 EP - 302 ER - TY - JOUR A1 - Löwe, Katharina A1 - Wozny, G. T1 - Feedforward control based on online concentration calculation of a heat- and mass-integrated distillation system JF - Computer Aided Chemical Engineering Y1 - 2000 U6 - https://doi.org/10.1016/S1570-7946(00)80027-9 SN - 1570-7946 VL - 8 SP - 151 EP - 156 ER -