Investigating the Effect of Temperature and Pressure Changes in the NHT Unit Reactor on Catalyst Crushing and Catalyst Cake Formation

This study investigates the impact of operational temperature and pressure variations in the naphtha hydrotreating (NHT) unit reactor on catalyst degradation mechanisms, specifically focusing on catalyst crushing and catalyst cake formation. As part of the hydrotreating process, the reactor operates under high thermal and mechanical stresses, making catalyst stability a key factor in maintaining process efficiency and minimizing downtime. Using simulated process data, a correlation was developed between temperature (۳۴۰–۴۰۰ °C), pressure (۳۰–۶۰ bar), and two key indicators, such as the Catalyst Crushing Index (CCI) and Catalyst Cake Thickness (CCT). Results indicate that both temperature and pressure significantly contribute to physical deterioration of the catalyst bed. Elevated temperatures accelerate particle fatigue, while increased pressure enhances mechanical compaction, leading to catalyst crushing and excessive cake buildup. The findings reveal a nonlinear increase in the crushing index, particularly above ۳۷۰ °C and ۴۵ bar, indicating a sharp decline in catalyst structural integrity. Catalyst cake thickness also grows rapidly under high-pressure conditions, leading to flow resistance, pressure drops, and reduced mass transfer efficiency. The study underscores the importance of maintaining operational conditions within safe limits to avoid premature catalyst failure. It also recommends periodic monitoring of pressure profiles and catalyst bed conditions, as well as the potential use of mechanically reinforced catalyst supports. This research provides valuable insights for optimizing NHT reactor performance and extending catalyst life in high-demand refining environments.

کلیدواژه ها:

Temperature and Pressure ، NHT Unit Reactor ، Catalyst Crushing ، Catalyst Cake Formation