The Use of Pinch Technology to Reduce Utility Consumption in a Natural Gas Processing Plant

Abstract

The present work aims at investigating opportunities for energy conservation in Western Desert Gas Complex (WDGC) through modification of the heat exchanger train. Process simulation of the plant was performed using HYSYS steady-state simulation program. This step was necessary to furnish stream property data requested for heat analysis as well as condenser and reboiler duties. Adopting the pinch design technology, minimum heating and cooling energy requirements were calculated for different values of minimum approach temperature (ΔT_min). Two methods were used, the problem table algorithm of the pinch method and the linear programming method. Then designing the heat exchanger network (HEN) took place according to the pinch design method to achieve target utilities for each ΔT_min. The optimum HEN is that which achieves considerable heat recovery with least annualized total cost. The optimum HEN design was found to correspond to ΔT_min of 10°C and achieved saving of hot and cold utilities as 42 and 21%, respectively, compared to the actual utilities consumption of the existing plant. These savings can be realized by adding only two heat exchangers to the existing network with a payback period of ≈1 year.