On the Similarity of Area Targets and Shells Targets in Heat Exchanger Networks

Abstract

The synthesis of heat exchanger networks (HEN) is an important field in process systems engineering, and considerable research efforts have been directed towards this goal in the past four decades. Many methodologies have been proposed to optimize the energy consumption in the process industries, with objectives of minimum utility consumption, minimum heat exchanger area, minimum number of heat exchange equipment, and minimum overall annualized cost. The strength of the Pinch Technology, the heuristics-based design and optimization method for HEN, lies in setting targets before the design. These targets, viz., area targets, units targets, shells targets, and total cost targets, are later used in arriving at optimal HEN. In the present paper, a new methodology has been presented which demonstrates the similarity of area targets and shells targets in an HEN employing multipass heat exchangers. Since area targets are inaccurate and fraught with uncertainties, it is pertinent to replace them with shells targets. Based on this, a design heuristics has been proposed for achieving optimal HEN.