Total Site Targeting with Stream Specific Minimum Temperature Difference

1. Total Site Targeting with Stream Specific Minimum Temperature Difference Zsófia Fodora, Jiří J. Klemeša, Petar S. Varbanova, Michael R.W. Walmsleyb,Martin J. Atkinsb, Timothy G. Walmsleyb aCentre for Process Integration and Intensification - CPI2, Research Institute of Chemical and Process Engineering - MŰKKI, Faculty of Information Technology, Egyetemutca 10, 8200 Veszprém, Hungary bEnergy Research Group – Industrial Energy Efficiency Division, Faculty of Science & Engineering, The University of Waikato, Hamilton 3240, New Zealand Introduction: • The new methodology is an extension of the traditional Total Site Integration methodology to produce more meaningful utility and heat recoverytargets for the processdesign • Deals with stream specific ΔTmininside each process, setting different ΔT contribution (ΔTcont) between the process streams and the utility systems • A diary factorycase study shows the differences between the traditional, process specific and stream specific Total Site Methodologies Case Study Processes utility requirements - comparison Process Specific Targeting Methodology Stream Specific Targeting Methodology Step 2: To account for individual stream characteristics, individual ΔTcont values are needed for each stream in the process-level analysis. ΔTcont,Pi: Minimum allowed temperature contribution for process individual hot stream, i. ΔTcont,Pj: Minimum allowed temperature contribution for process individual cold stream, j. Step 4: Shifting back. Shift of the extracted segments back to the temperature levels of the process streams: Step 6: Shift the extracted GCC segments to the temperature scale of the utilities using the utility process ∆T contribution: ΔTcont,Ui: Minimum allowed temperature contribution for specific heating utility ΔTcont,Uj: Minimum allowed temperature contribution for specific cooling utility Step 6:Shifting forward. Shift the extracted segments to the temperature scale of the utilities: ∆Tmin,pp :Minimum allowed temperature difference between the processes ∆Tmin, PCU :Minimum allowed temperature difference between the process - cold utility ∆Tmin, PHU : Minimum allowed temperature difference between the processes – hot utility • Conclusions: • The procedure allows making differences between heat transfer in the process streams inside the process and between process to utility. • Case study compares the traditional targeting procedure and with the recently developed extended methodology. • The extended methodology gives more meaningful results reducing the over or under estimated heat exchanger areas in the process design. • Acknowledgement: • The financial support is gratefully acknowledged Efficient Energy Integrated Solutions for Manufarturing Industries -EFENIS, grant agreement No. ENER/FP7/296003/EFENIS