ABSTRACT
Andrej Szíjjarto*, Stavros Papadokonstantakis and Konrad Hungerbühler Safety & Environmental Technology Group Swiss Federal Institute of Technology (ETH), CH-8093 Zürich, Switzerland
ABST R AC T Presently, energy saving motivation of the chemical manufacturers is growing due to high prices of the primary energy sources. Therefore, efcient and reliable methodologies and tools allowing analysis and optimization of the energy demand are of high importance for the industry. Developed methodology for the identication of the optimization potential signicantly simplies the energy-saving efforts in multipurpose chemical batch plants. The investigation of the energy-saving potential was carried out in two stages comprising efciency screening on the plant level followed by a detailed analysis of the unit operations (UOs) in the production lines. The proposed efciency screening of the steam usage in the UOs on the plant level facilitates the selection of the targets for the further detailed analysis. The efciency of a particular UO was calculated batch-wise and averaged over a period of 60 days for 19 different UOs. The UOs with low batch-averaged thermal efciency in combination with high standard deviation of the efciency values were identied as most important optimization spots. Two production lines were investigated in a detailed analysis. Signicant energy consumption was identied within the synchronization steps which are representing a non-productive part of the batch production. It was identied that the high energy consumption in the synchronization steps was caused by overheating/
CONTENTS
Introduction ......................................................................................................... 462 Analysis of Potential Energy Savings .............................................................. 462 Detailed Investigation of the Energy Use ........................................................464 Production Lines Energy Savings .....................................................................466 Conclusions .......................................................................................................... 467 Acknowledgments ..............................................................................................468 References .............................................................................................................468
