Mejores Prácticas
Simulación para la industria de Hidrocarburos.
4 Proyectos Relevantes.
Dr. Humberto Hinojosa Dr. Moisés Hernández
Hidrodinámica y dispersión del efluente del difusor marino de la Terminal Marítima
Dos Bocas, Tabasco.
Descripción: El sistema de disposición final de aguas congénitas, derivadas del proceso de acondicionamiento de hidrocarburos en la terminal marítima de dos bocas, cuenta con pozos letrina y un difusor marino. El presente estudio tridimensional busca describir de forma detallada la dispersión de sal y el perfil de temperaturas en el área alrededor del difusor marino así como establecer el área de impacto de dicha descarga. Datos Importantes:
Descarga: 90,000 ppm de sal
34 ºC 300,000 BPD
Agua de mar:
36,00 ppm de sal 24 ºC
Corrientes marinas.
Ubicación:
Diseño:
Diseño:
Parte 1: Difusor
Parte 1: Difusor
Parte 1: Difusor
Parte 1: Difusor
Parte 1: Difusor
Resultado:
Perfil de flujo de agua congénita a lo largo del difusor.
Parte 2: Difusor + Entorno
Parte 2: Difusor + Entorno
Parte 2: Difusor + Entorno
Parte 2: Difusor + Entorno
Parte 2: Difusor + Entorno
Parte 2: Difusor + Entorno
Parte 2: Difusor + Entorno
Parte 2: Difusor + Entorno
Parte 2: Difusor + Entorno
Parte 2: Difusor + Entorno
Parte 2: Difusor + Entorno
Parte 2: Difusor + Entorno
Parte 2: Difusor + Entorno
Parte 2: Difusor + Entorno
Parte 2: Difusor + Entorno
Resultados:
Perfil de concentraciones de sal.
Perfil de temperatura.
Área de impacto delimitada.
Plataforma de Estabilizado y Cabezal de Gas.
Modelo geométrico tridimensional estructural de los equipos, líneas, válvulas y accesorios.
Cabezal de recolección de gas – TMDB
Cabezal de recolección de gas – TMDB
Cabezal de recolección de gas – TMDB
Hydrodynamic Analysis of the Dehydration Process of one Mexican Oil in an Electrostatic Vessel using
ANSYS CFX
Objectives:
• Crude oil dehydration. • Meet quality standards. • Evaluate performance equipment under different
operation conditions.
Electrostatic Separator Vessel: Main components:
• Vessel • Emulsion Distributor. • Water Collector. • Oil Collector. • Electrodes.
Vessel
Water Collector
Emulsion Distributor
Shrouds
Electrodes:
Oil Collector
Internals
Internals
Internals Details
Complete Geometric Model
Complete Geometric Model
Complete Geometric Model
Complete Geometric Model
Hydrodynamic Analysis: Domain Discretization. Fluids Properties. Physical Models. Results.
Discretization
Discretization 5 Million Elements Free Mesh
Mesh Detail
Wired Model
Fluids Properties Oil: Density: 19 oAPI Viscosity: 10 cP Flow: 200’000 BPD Water: Density: 998.7 kg/m3
Viscosity: 0.29 cP Interfacial Tension: 25 dina/cm Flow: 66’667 BPD Mean Particle Diameter: 400 micron
Hydrodynamic Model No homogeneous Multiphase Flow (Euler-Euler). Continuous Phase – Oil Dispersed Phase – Water Isothermal: 220 oF Drag Coefficient: Ishii – Zuber (1979). Ishii,M., Zuber, N. (1979).”Drag coefficient and relative velocity in bubbly, droplet or particulate flows”, AIChE Journal, 25(5), pp. 843-855.
Flow Morphology Isao Kataoka, Kenji Yoshida, Masanori Naitoh, Hidetoshi Okada and Tadashi Morii (2012). Transport of Interfacial Area Concentration in Two-Phase Flow, Nuclear Reactors, Prof. Amir Mesquita (Ed.), ISBN: 978- 953-51-0018-8, InTech, Available from: http://www.intechopen.com/books/nuclear-reactors/transport-of- interfacial-area-concentration-in-two-phase-flow
Electrocoalescence Model A.K. Das, J.R. Thome and P.K. Das, Transition of Bubbly Flow in Vertical Tubes: New Criteria Through CFD Simulation, J. Fluids Eng. 131(9), 091303 (Aug 18, 2009) (12 pages).
Electrocoalescence Model P. Atten, "Electrocoalescence of water droplets in an insulating liquid", J. Electrostatics, vol. 30, pp. 259–270, 1993. J. Raisin, “Electrocoalescence in water-in-oil emulsions: towards an efficiency criterion”, PhD thesis, Grenoble University, 2011.
Water Particles Polarization.
Electrostatic Forces between two polarized water Droplets.
Melheim, J. A., Chiesa, M., Ingebrigtsen, S., Berg, G., 2004. Forces between two water droplets in oil under the influcence of an electric field. In: 5th Inter- national Conference on Multiphase Flow. Yokohama, Japan, paper # 126.
Interfacial area density transport equation. G. Kocamustafaogullari and M. Ishii, “Foundation of the interfacial area transport equation and its closure relations,” International Journal of Heat and Mass Transfer, vol. 38, no. 3, pp. 481–493, 1995. M. Ishii and S. Kim, “Development of one-group and two-group interfacial area transport equation,” Nuclear Science and Engineering, vol. 146, no. 3, pp. 257–273, 2004.
Source Term. R=Collision Frequency X Coalescence Efficiency
J. Raisin, “Electrocoalescence in water-in-oil emulsions: towards an efficiency criterion”, PhD thesis, Grenoble University, 2011.
Results: Pressure Field
Results: Oil Velocity Field
Results: Oil Velocity Vectors
Results: Water Velocity Field
Results: Water Volume Fraction
Results: Mean Particle Diameter
Results: Mean Particle Diameter
Capabilities: Separation Efficiency Determination as function: Process Variables: Temperature. Flow. Water Content. API degrees.
PVT module coupled with ANSYS-CFX
Basic Ideas:
• In order to perform reliable CFD simulations for the Oil & Gas industry, it is important to know:
What kind of fluid are we dealing with? Heavy Oil. Light Oil. Gas – Condensate.
How many phases will be present for a given process? Liquid – Vapor. Liquid – Liquid. Liquid – Liquid – Vapor. Fluid – Solid.
What are the physical properties for each phase? Density. Viscosity… at least.
Basic Ideas:
• All this information can be obtained from what in the Oil & Gas Industry is known as “PVT Module”. To extend the application of CFX to deal with complex fluids
such as reservoir fluids, an easy connection between a PVT module and ANSYS CFX is needed.
In this presentation, we would like to show the connection between a PVT module and ANSYS CFX.
Outline:
• Characterize a reservoir fluid using an “In-House” developed PVT Module. Cubic Equation of State based Software. PVT calculations: Bubble points. Dew points. Flash at constant T and P.
• Generate physical properties for EVERY possible phase present for a given process.
• Generate intput data file for a Fortran Compiled Library. (PVT – ANSYS connection)
• Read CCL file to use the Library. • Perform CFD simulation using the calculated properties.
Characterize a reservoir fluid: “In-House” developed PVT Module
Composition of the reservoir fluid
Characterization Options for the Heavy Fraction.
Characterization Options for the Heavy Fraction.
PVT experiments that can be simulated:
• Phase Envelope • CCE • DLE • CVD • MMP • Swelling Tests
Phase Envelope
Calculation Progress
Phase Envelope
DLE
Calculation Progress
DLE
Properties DATA file in library path
ANSYS configuration after CCL file has been imported
Simulation Results Example:
Flashing of a Volatile Oil flowing through a butterfly valve
41 0API Oil RGA : 67.40
Pressure Field
Velocity Field
Gas Volume Fraction
Simulation Results:
Real properties for the 2 phases (gas and oil)
Equilibrium line crossing implies a
phase change. (Flashing)
This module was used along with ANSYS – CFX in the following project:
Hydrodynamic Description of a 140 km
crude oil transport line.
Fluid Properties:
35 oAPI RGA: 8
14%Vol. Water Content
Fluid Characterization and Properties:
Componente % mol PM (g/mol) Tc (K) Pc (bar) ω
N2 0.00061 28.01 CO2 0.00087 44.01 H2S 0.00346 34.08 C1 0.01231 16.04 C2 0.01267 30.07 C3 0.02299 44.10 iC4 0.00692 58.12 nC4 0.02829 58.12 iC5 0.01654 72.15 nC5 0.02953 72.15 C6 0.05455 84.00
Pseudo1 0.14158 102.54 557.43 33.93 0.31074 Pseudo2 0.24920 147.65 626.71 29.02 0.40041 Pseudo3 0.23146 233.29 737.83 19.60 0.63706 Pseudo4 0.13852 370.19 840.28 13.59 0.92242 Pseudo5 0.05050 588.11 938.69 9.63 1.25656
0
5
10
15
20
25
30
35
40
45
50
100 200 300 400 500 600 700 800
Temperatura (K)
Pres
ión
(bar
)
Complete Line – Pressure Drop
Complete Line – Phase Change
Complete Line – Water Bed
Predicted Oil volume loss due to evaporation
Thank you for your time!
Q & A?