(50a) Rigorous Simulation of a Crude Distillation Unit with Heat Exchanger Network

Crude distillation is one of the most important operations in oil refineries since it provides feed to downstream units for further processing. Because of the nature of the present complex and highly integrated refineries, it is critical to understand the operation of the crude distillation unit (CDU) in order to accurately predict the performance and thereby plan operations of the downstream units in response to market demand of the different products. 

The present study focuses on simulation of a CDU using a commercially available process simulator Petro-SIM. A detailed model has been developed and validated using refinery operating data. A sensitivity analysis of the model has also been conducted for incorporating different property packages, and Peng-Robinson Equation of State has been found to provide excellent predictions for the CDU performance. Parametric studies have been performed for key operating scenarios in order to understand the relationship among process parameters, feed qualities and product profiles and properties. Different scenarios were studied to demonstrate effects of draw rates of different products on the respective cut properties. Such a robust predictive model opens up opportunities for CDU operational optimization, contributing to an overall refinery profit margin enhancement. The CDU consumes a significant amount of energy. In order to conduct energy optimization studies, e.g. using pinch analysis technique, a detailed accurate model such as the one being presented would be highly useful.