Dynamic Modelling and Simulation of A Three-Phase Gravity Separator

Abstract

There are many studies addressing in detail, the separation mechanisms, sizing, and design of the crude oil separation process using the horizontal 3-Phase Gravity Separators. Surprisingly, however, there are very few publications about their dynamics, modeling, and simulation. An understanding of its dynamic behavior will facilitate the design and tuning of the device that can be used to regulate the water level, oil level, and gas pressure against feed variations. This Scientific Paper presents a full mathematical analysis, modeling, and simulation using Mathworks Matlab R2016b-x64, modeling and simulation using Aspen Hysys V10 of a Crude Oil Separation Process using a horizontal 3-Phase Gravity Separator. Equations developed called Bishoy’s Equations will help to operate this device and to find many parameters and to see the effect of a parameter on others. The Assumptions are: complete phase separation, the vapor phase behaves like an ideal gas, and liquids densities are constant. Also, in practice, separators are designed with internal baffles to promote laminar flow to increase the efficiency of the separator, but it has been assumed that there are no baffles here which is a big problem but with the aid of these equations, the horizontal three-phase gravity separator can be operated at its maximum efficiency. The following parameters were determined in the equations: The height of gas, height of the water, height of oil, the height of oil when jumping the weir, the pressure of the gas (in and out), the pressure of water (in and out), the pressure of oil (in and out), and the effect of increasing  (control valve’s stem position) and decreasing  (inlet volumetric flowrate) on these parameters has been studied. This paper can change the view on oil and gas extraction and processing and can help large oil and gas companies in Europe, Asia, and Africa.