Simulation and performance analysis of a Naphtha Hydrotreating (NHT) process using Aspen HYSYS

This study presents a comprehensive simulation and analysis of a Naphtha Hydrotreating (NHT) unit, focusing specifically on the reaction section to evaluate operating conditions and enhance product quality using Aspen HYSYS® V12.1 (Aspen Technology, Inc.) simulation software. A continuous reactor model was developed to simulate the complex chemical transformations of C5–C12 paraffins, naphthenes, and aromatics. The methodology emphasizes the integration of catalytic reforming components and the calibration of separator logic to ensure thermodynamic consistency between the vapor and liquid phases. The findings indicate that precise management of the highly exothermic temperature rise during the initial hydrotreating (desulfurization) stage, followed by the management of the highly endothermic heat loss across the subsequent multi-bed catalytic reforming reactor system—typically operating between 280 and 425 °C—is critical for achieving deep desulfurization and optimal product yields. The results demonstrate that the simulated unit effectively reduces the sulfur content to less than 0.5 ppm, providing a technical framework for improving fuel quality, meeting environmental standards, and maximizing the recovery of high-purity hydrogen and light hydrocarbon by-products.