A new Gasoil Hydrotreater (GOHT) is design to produce low-sulfur feed for the Fluidized Catalytic Cracking (FCC) Units by combining high-sulfur gasoil with hydrogen and passing the mixture through a catalyst bed at high temperature and pressure. Uneven splitting and/or phase separation of the original stream can lead to higher mass flow in some passes than others causing uneven heating as well as high furnace tube metal temperatures. This can lead to shorter tube life and potentially tube rupture. Computational Fluid Dynamics (CFD) simulation and virtual reality visualization have been used to determine the two-phase flow regime throughout the piping system and to investigate the degree to which each flow split is uneven.
- Based on the drawings provided by BP, the computational geometries of the GOHT furnace piping system has been developed.
- A three-dimensional geometry has been built from the drawings and the drawings show the detailed isometric drawings of the entire piping system and gives three different views of the simulation geometry.
- There are four outlets and one inlet, and the whole pipe system has pipes of three different diameters. In this study, four sets of different boundary conditions have been considered. They are: Start-of-Run (SOR), End-of-Run (EOR), Start-of-Run-Turned-Down (SOR T/D) and End-of-Run-Turned-Down (EOR T/D) conditions.
- The mass flow rate at the inlet and properties of hydrogen and gas-oil have been defined. Due to the dominance of momentum in the piping system, the chemical reactions and heat transfer has not been modeled in this study. Isothermal conditions have been applied for all the simulations.
Click the movie below to see GOHT Piping in detail.
Faculty Collaborator: Dr. Chenn Q. Zhou