Heat Exchanger Network Retrofit for Energy Savings in a Catalytic Reforming Naphtha Unit at Zawia Oil Refinery Using Pinch Technology

Abstract

Energy conservation in oil refineries is essential for reducing operational costs and minimizing environmental emissions. One effective approach is optimizing the Heat Exchanger Network (HEN) design. In this research, pinch technology was applied to optimize the preheat exchanger network of the catalytic reforming unit at the Zawia Oil Refining Plant. The optimized configuration simplified the network to one heater and three coolers, significantly reducing the need for external utilities. The analysis was performed using HINT software. Results showed that the optimal minimum temperature difference (ΔTmin) is 25°C, while the pinch point was identified at 212.5°C. The minimum heat required from hot utilities was 4450.09 kW, and 3932.73 kW needed to be removed by cold utilities. The annual operating cost for hot and cold utilities was estimated at $573,329.7, while the annual capital cost was $100,108.7, resulting in a total annual cost of $673,438.4. Although these values do not represent the total plant energy savings, they highlight the strong potential of pinch analysis to improve thermal efficiency, reduce energy waste, and support sustainable operations in energy-intensive industries.