Simulation-based approach for integrating work within heat exchange networks for sub-ambient processes

Abstract

Integrating work synergistically within heat exchange networks can offer considerable energy savings. Several publications have attempted to optimize this integration using a mathematical programming approach. However, the equation-based approach necessitates simplifications, and requires analytical correlations that often fail to reflect thermophysical properties accurately. In this article, the first simulation-based methodology is presented for work-integrated heat exchange network synthesis, which needs no correlations or simplifying assumptions. For this, a generalized superstructure is proposed, which not only accommodates the liquid and vapour-liquid phases, but also reduces the feasible search region for network synthesis. Particle swarm optimization has been used as the more suitable method for the proposed non-convex multi-modal simulation-based optimization problem. The methodology is illustrated using several scenarios of a literature case study on a liquid energy chain.