Heat exchanger network retrofit by a shifted retrofit thermodynamic grid diagram-based model and a two-stage approach

Abstract Graphical tools are useful in the heat exchanger network (HEN) retrofit to maximise energy savings. The disadvantage of heuristic rules, which are usually applied to make retrofit decisions using graphical tools, is that they could lead to sub-optimal solutions. The presented study developed a two-stage method for HEN retrofit. In the first stage, a mixed-integer linear programming (MILP) model is formulated based on the structure of the shifted retrofit thermodynamic grid diagram (SRTGD) to minimise the utility cost and investment. The non-linear equations for the investment cost calculation were linearised, and the parameters in the linearised equations were obtained using data regression. In the second stage, a particle swarm optimisation (PSO) algorithm was selected and applied to adjust the inlet and outlet temperatures of heat exchangers with the aim of minimising the payback period on the basis of the first-stage solution. The proposed two-stage procedure combines the strengths of the MILP and PSO methods, offering convenient interfaces for user interaction and results interpretation. Two cases were studied to verify the effectiveness of the method. Case 1 and Case 2 decreased the payback period by 11.6% and 21.7% compared to the results obtained in previous retrofit applications.

[1]  Ebrahim Rezaei,et al.  Heat exchanger networks retrofit by coupling genetic algorithm with NLP and ILP methods , 2009, Comput. Chem. Eng..

[2]  Ignacio E. Grossmann,et al.  A screening and optimization approach for the retrofit of heat-exchanger networks , 1991 .

[3]  René Hofmann,et al.  A Novel Approach for Linearization of a MINLP Stage-Wise Superstructure Formulation , 2018, Comput. Chem. Eng..

[4]  Igor Bulatov,et al.  Novel MILP-based iterative method for the retrofit of heat exchanger networks with intensified heat transfer , 2012, Comput. Chem. Eng..

[5]  Serge Bédard,et al.  Optimal retrofit of heat exchanger networks: A stepwise approach , 2017, Comput. Chem. Eng..

[6]  Mauro A.S.S. Ravagnani,et al.  Heat Exchanger Network Synthesis without stream splits using parallelized and simplified simulated Annealing and Particle Swarm Optimization , 2017 .

[7]  Viviani C. Onishi,et al.  Retrofit of heat exchanger networks with pressure recovery of process streams at sub-ambient conditions , 2015 .

[8]  Petar Sabev Varbanov,et al.  Shifted Retrofit Thermodynamic Diagram: A Modified Tool for Retrofitting Heat Exchanger Networks , 2014 .

[9]  Petar Sabev Varbanov,et al.  A Procedure for the Retrofitting of Large-scale Heat Exchanger Networks for Fixed and Flexible Designs Applied to Existing Refinery Total Site , 2015 .

[10]  Jiří Jaromír Klemeš,et al.  A retrofit framework for Total Site heat recovery systems , 2014 .

[11]  Robin Smith,et al.  Heat exchanger network retrofit optimization involving heat transfer enhancement , 2012 .

[12]  Aline P. Silva,et al.  Particle Swarm Optimisation Applied in Retrofit of Heat Exchanger Networks , 2009 .

[13]  Gunawan Nugroho,et al.  Heat exchanger network retrofit throughout overall heat transfer coefficient by using genetic algorithm , 2016 .

[14]  Xing Luo,et al.  Studies on the retrofit of heat exchanger network based on the hybrid genetic algorithm , 2014 .

[15]  Sirous Shafiei,et al.  Heat exchanger networks retrofit with considering pressure drop by coupling genetic algorithm with L , 2011 .

[16]  Paul Stuart,et al.  Linking pinch analysis and bridge analysis to save energy by heat-exchanger network retrofit , 2016 .

[17]  Bohong Wang,et al.  Heat transfer enhancement, intensification and optimisation in heat exchanger network retrofit and operation , 2020 .

[18]  Robin Smith,et al.  Cost-effective strategy for heat exchanger network retrofit , 2017 .

[19]  Petar Sabev Varbanov,et al.  Heat exchanger network retrofit supported by extended Grid Diagram and heat path development , 2015 .

[20]  Lixia Kang,et al.  A systematic strategy for multi-period heat exchanger network retrofit under multiple practical restrictions , 2017 .

[21]  Fatma H. Ashour,et al.  Temperature driving force (TDF) curves for heat exchanger network retrofit – A case study and implications , 2017 .

[22]  René Bañares-Alcántara,et al.  A Novel Visualization Tool for Heat Exchanger Network Retrofit , 1996 .

[23]  Nathan S. Lal,et al.  A novel Heat Exchanger Network Bridge Retrofit method using the Modified Energy Transfer Diagram , 2018, Energy.

[24]  Zainuddin Abdul Manan,et al.  Customised retrofit of heat exchanger network combining area distribution and targeted investment , 2019, Energy.

[25]  Petar Sabev Varbanov,et al.  Rules for paths construction for HENs debottlenecking , 2000 .

[26]  Robin Smith,et al.  Heat exchanger network retrofit with a fixed network structure , 2014 .

[27]  Sharifah Rafidah Wan Alwi,et al.  STEP—A new graphical tool for simultaneous targeting and design of a heat exchanger network , 2010 .

[28]  Jiří Jaromír Klemeš,et al.  Process modifications to maximise energy savings in total site heat integration , 2015 .

[29]  Igor Bulatov,et al.  New MILP-based iterative approach for retrofitting heat exchanger networks with conventional network structure modifications , 2013 .

[30]  Mauro A.S.S. Ravagnani,et al.  Heat exchanger networks retrofit with an extended superstructure model and a meta-heuristic solution approach , 2019, Comput. Chem. Eng..

[31]  Jacek Jeżowski,et al.  A new methodology for simultaneous optimization of capital and operating cost targets in heat exchanger network design , 2000 .

[32]  Zdravko Kravanja,et al.  MINLP retrofit of heat exchanger networks comprising different exchanger types , 2004, Comput. Chem. Eng..

[33]  Aline P. Silva,et al.  Particle Swarm Optimisation in heat exchanger network synthesis including detailed equipment design , 2008 .

[34]  Sharifah Rafidah Wan Alwi,et al.  Simultaneous diagnosis and retrofit of heat exchanger network via individual process stream mapping , 2018, Energy.

[35]  Zainuddin Abdul Manan,et al.  Heat exchanger network retrofit using individual stream temperature vs enthalpy plot , 2017 .

[36]  Jiří Jaromír Klemeš,et al.  Forty years of Heat Integration: Pinch Analysis (PA) and Mathematical Programming (MP) , 2013 .

[37]  Mamdouh A. Gadalla,et al.  A new graphical method for Pinch Analysis applications: Heat exchanger network retrofit and energy integration , 2015 .

[38]  Haibo Zhang,et al.  One-step approach for heat exchanger network retrofitting using integrated differential evolution , 2013, Comput. Chem. Eng..

[39]  Chuei-Tin Chang,et al.  An improved design method for retrofitting industrial heat exchanger networks based on Pinch Analysis , 2019, Chemical Engineering Research and Design.