The Use of ExPAnD in Cyclic Low Temperature Processes

• Main Author: Marashi, Seid Ehsan
• Format: Others
• Language: English
• Published: Norges teknisk-naturvitenskapelige universitet, Institutt for energi- og prosessteknikk 2011
• Subjects: ntnudaim:6385; MSGASTECH Natural Gas Technology
• Online Access: http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-14419

The pinch analysis method has been applied to different processes successfully for heat integration. Since it does not include pressure as a factor in low temperature processes and it has important role in those processes, Extended Pinch Analysis and Design (ExPAnD) method has recently developed for heat integration in low temperature processes.The main motivation for this Master thesis is to further develop the ExPAnD methodology by considering cyclic processes and utilities, where the quality of the design is measured by the Exergy Transfer Effectiveness (ETE). In this project, the exergy concept is studied. A review among literatures has been done and different definitions for exergy efficiency are identified. The pinch analysis method and ExPAnD method are also reviewed briefly. Exergy analysis based on Exergy Transfer Effectiveness (ETE) has been applied to operation units which are used in LNG production processes. Moreover, dual independent expander refrigeration cycles process for LNG production has been analyzed from the exergy point of view. The related heuristic rules of ExPAnD method are studied. This method has been applied to the process of dual independent expander refrigeration cycles successfully. Finally, a new approach is proposed which improves the exergy efficiency of the cyclic low temperature processes.