DESIGN, MODELLING AND SIMULATION OF CRUDE OIL DISTILLATION PLANT

ABSTRACT

This research presents a flexible design model and robust algorithm for simulation of a crude oil plant which consists of a main column with several side strippers and pumparounds. The model is developed in commercial software HYSYS, Pro/II and Aspen Plus, in order to evaluate the performance of the simulation of these models on personal computers. The development of the mathematical model of the equipments of the unit is based on the relations that are presented in the equilibrium stages. The use of Peng Robinson thermodynamic model and the MESH equations allow the construction of a rigorous model, which is solved using the inside-out- algorithm. From the study of the degree of freedom of the system, a completely specified model is built; this enables the analysis of the effect of different variables in the operation of the unit. The proposed algorithm effectively accelerates the speed of convergence and offers better stability by introducing a damping factor for updating the stripping factor, and also reduces the requirement on the initial estimates by updating the Jacobian matrix directly with the stripping factor and enthalpy. Furthermore, this model is based on pseudo- components and makes use of the well-known MESH equations, in an original approach following topological and functional rules. The results showed that the proposed algorithm was reliable, fast in convergence and of lower computer cost. Additional simplifications results in a robust dynamic model with reasonable accuracy, without affecting the “full-scale” model feature and the detailed mathematical model explicitly oriented to numerical integration within an appropriate simulation environment.