Coupling Refrigeration System Synthesis and Heat Exchanger Network Design

Abstract

Designing an optimal refrigeration system for a chemical plant is a very challenging task not only because of the involved process complexity but also the significant relationship between its performance and the plant’s profitability. This paper introduces a methodology framework for optimal synthesis of a cascade refrigeration system (CRS) coupled with heat-exchanger network (HEN) design by systematically utilizing process simulation, mathematical programming, pinch analysis, and HEN design heuristics. The refrigeration system is firstly optimally synthesized, which provides inputs to design the coupled heat exchanger network and then validated by rigorous simulations. A case study of a propylene refrigeration system in an ethylene plant is demonstrated. The resulted refrigeration schematic proves to be efficient in utilizing the available refrigerant to satisfy all process heating/cooling demands.