Synthesis of heat exchanger network considering pressure drop and layout of equipment exchanging heat

• Developed MINLP model to optimize total annual cost of HEN (Heat Exchanger Network).
• Pressure drop of streams and pipe and piping investment are included in the model.
• Detailed plant layout is accounted to include pressure drop in pipe and piping cost.
• Considering power and piping costs in TAC design of HEN are altered significantly.

The present work is related to development of a MINLP (Mixed integer non linear programming) model for the synthesis of HEN (heat exchanger network) considering pressure drop through connecting pipelines, heat exchangers and the layout of the equipment exchanging heat simultaneously. The pressure drop of shell and tube sides in a heat exchanger is considered in the model. Further, detailed plant layout is considered for accounting pressure drop in pipe line as well as piping cost. The objective function of the MINLP model is the TAC (total annual cost), which considers utility cost, capital investment cost of exchangers, pipe investment cost and pumping cost due to pressure drops in exchanger as well as in pipe length. The developed model is illustrated using a case study. The results show that the TAC of HEN is reduced by 27.4% than that obtained for the topology without considering pressure drop in exchanger. However, placement of exchangers in the layout contributes to 4.5% in TAC. Results found through the present model are compared with that of published models.