Multiphase flow simulators for heavy oil; Innovations to be expected. Norbert Hoyer February 2009

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1 Multiphase flow simulators for heavy oil; Innovations to be expected Norbert Hoyer February

2 Heavy Crude Oils Heavy crude oils much more important now than in past Constitute large part of remaining oil reserves Type API gravity Density (kg/m 3 ) Viscosity (cp) s.t.c. Bitumen << > 10,000 Extra heavy oil < > 1000 Heavy oil > 100 Medium oil Light oil > 31.1 < 870 < 10

3 Heavy Crude Oils Heavy Oil production may require specific Production methods Transportation methods Multiphase flow modelling Laminar flow Closure relations like void in slugs Non-Newtonian flow Flow patterns and transitions Separation Fluid properties Viscosities Emulsions Thermal flow behaviour

4 Heavy Crude Oil Production Methods Primary production methods Pumping Multilateral wells Cold production with sand (CHOPS) Cold EOR Water flooding Vapour extraction Thermal methods SAGD Other (Picture: trehugger.com)

5 Heavy crude oil transportation challenges High oil viscosity Wax and sand increase the problem Water droplets can increase or decrease viscosity Small drops give increase, large drops give decrease Flow enhancement methods: Keep oil temperature high Emulsify oil in water Upgrade oil in situ Dilute oil with condensate or light oil Each of these methods viable under some conditions Each have their own challenges

6 Emulsion Properties Natural and added surfactants influence Interfacial tension and interfacial rheology Emulsion stability Phase inversion Particles (fines) often increase emulsion stability Newtonian and non-newtonian Large differences in predictions Major variables: Water cut Droplet sizes Shear rate Temperature Wax appearance temperature Inversion point μ inv WC

7 OLGA development levels General development Improvements and new functionality OVIP JIP OLGA Validation and Improvement Project Wellbore and Near Wellbore JIP SAGD and other improvements, OLGA Rocx HORIZON JIP Long distance transport/complex deep water fields Next generation of OLGA Flow models FACE JIP Virtual Multiphase Flow Assurance Center (SFI/CRI) IFE - SINTEF - NTNU 7

8 SPT working with lead users in Joint Industry projects like HORIZON and OVIP Research OLGA user community TUFFP RESEARCH "OLGA" PRODUCTION VERSION "OLGA"

9 Heavy oil work in OVIP New emulsion viscosity correlations in OLGA Implemented correlations from open literature Additional, improved correlation to be implemented Improved table based input of emulsion viscosity Modify correlation for oil-water mixing in OLGA Stratification of oil and water at intermediate water cuts OLGA tends to underpredict pressure drop for heavy oils We need more detailed lab data for modelling Slug flow Oil/water flow

10 Cross sectional flow model: Laminar heavy oil layer turbulent gas Gas: 2D velocity distribution from Horizon model Liquid: 2D velocity distribution from analytic solution for laminar flow The Pre-integrated 2D model is combined with OLGA, yielding a 3D model with 1D computation time

11 Tulsa Fluid Flow Project SPT Group participates in the Tulsa Fluid Flow Project through the OVIP program in order to get high viscosity heavy oil flow data The OVIP program is also sponsoring a gamma instrument for TUFFP delivered by IFE 11

12 Systematic approach to improve OLGA s simulation capabilities Provide new technologies for specific production methods Single component flow for steam /SAGD (and CO2) First step in sand transportation modeling through JIP HORIZON I Update flow models and closure relations in ongoing JIP OVIP Specific tasks improving flow modeling Data collection through TUFFP 12

13 OLGA Technology Roll-Out Increasing interest for heavy oils in industry SPT Group accelerating related developments Stepwise roll-out of flow model improvements with respect to heavy oil features Some enabling technologies like single component flow models for steam (and also CO2) already available now SAGD Annual releases through OVIP project OVIP improvements implemented in following annual main releases of OLGA

14 Acknowledgments Thanks to contributions from: Jan Nossen (IFE) Dag Biberg (SPT Group)

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