Rigorous Dynamic Simulation of a Dehydration and Desalting Crude Oil Unit Using Aspen HYSYS®

Abstract

Considering that two-thirds of world oil production receive a treatment after extraction to remove water and salt contents, one of the most important processes to avoid operational problems in refinery plants corresponds to the dehydration and desalting unit. Here, live crude oil at high temperatures and pressures is processed and stabilized. Henceforth, to optimize these petrochemical plants, simulation has become an important tool. Nevertheless, due to its sequential modular nature related with mass/energy recycle steam circuits, the modelling and simulation of this process is commonly simplified. Thus, to reproduce the process behaviour of the unit under operating conditions and identify its effect on the final product, this work presents an unpublished rigorous dynamic simulation-based procedure of a complete real dehydration and desalting process using Aspen HYSYS ® . Different pieces of equipment are carefully designed based on literature review, and a specially tailored procedure is proposed to estimate the water and salt contents at any stage of the plant. Finally, to validate the simulation, the accuracy of the main flows and chemical contents along the process are compared with actual data.