Studies and Modeling for Upgrading Units for Heavy Oil Refineries


The primary objective of this study is to predict the optimum operating conditions required to operate an existing atmospheric distillation column to distillate heavier crude oils in same unit which designed mainly to fractionate moderate and lighter crude oils. Detailed simulation model of atmospheric distillation column was made using Aspen Hysys V. 8.4 software. The model built depending on the data of real plant which located in Al-Daura midland refinery company at Baghdad/Iraq. The crude oils were described using the true boiling point (TBP) assays and Peng-Robinson package were used to predict thermodynamic properties. Three different types of crude oils (Kirkuk light, Basrah light and Basrah medium) were selected to identify the model validity. The simulation results agree very well with the industrial plant results. Finally the proposed model was used to predict optimum operating conditions required to distillate a blend of light and heavy Basrah crude oil with different mixing ratios. The objective of the optimization is to predict the maximum profit of the products within the required specifications. At optimum operating conditions the total yearly profit for distillation of a blend of 50% vol. light+50% vol. heavy basrah crude oil was found to be 713.28 M$.