WINPROP USER GUIDEPHASE-BEHAVIOUR & FLUID PROPERTY PROGRAMVERSION 201414.WI.M4 This publication and the application described in it are furnished under license exclusively to the licensee, for internal use only, and are subject to a confidentiality agreement. They may be used only in accordance with the terms and conditions of that agreement. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic, mechanical, or otherwise, including photocopying, recording, or by any information storage/retrieval system, to any party other than the licensee, without the written permission of Computer Modelling Group. The information in this publication is believed to be accurate in all respects. However, Computer Modelling Group makes no warranty as to accuracy or suitability, and does not assume responsibility for any consequences resulting from the use thereof. The information contained herein is subject to change without notice. Copyright 2014 Computer Modelling Group Ltd. All rights reserved. The license management portion of this program is based on: Reprise License Manager (RLM) Copyright (C) 2006-2014, Reprise Software, Inc. WinProp uses Intel(R) Compilers. WinProp, CMG, and Computer Modelling Group are registered trademarks of Computer Modelling Group Ltd. All other trademarks are the property of their respective owners. Computer Modelling Group Ltd. 200, 1824 Crowchild Trail N.W. Calgary, AlbertaCanadaT2M 3Y7 Tel:(403) 531-1300Fax:(403) 289-8502E-mail: cmgl@cmgl.ca Preface WinProp is CMG's equation of state (EOS) multiphase equilibrium and properties determination program. WinProp features techniques for characterizing the heavy end of a petroleum fluid, lumping of components, matching laboratory PVT data through regression, simulation of first and multiple contact miscibility, phase diagrams generation, asphaltene and wax precipitation modeling, compositional grading calculations as well as process flow simulation. This User Guide presents a comprehensive description of the steps involved in obtaining a PVT data suitable for inclusion in data files for CMG's GEM, STARS or IMEX simulators. This User Guide is aimed at reservoir engineers who want to use WinProp to predict phase behavior of reservoir fluids as well as characterize these fluids for reservoir simulation. It requires some knowledge of phase behavior as it pertains to the different fluid types found in reservoirs. Every attempt has been made in the preparation of this User Guide to provide the user with all the necessary details. If questions arise, please contact: Computer Modelling Group Ltd. 200, 1824 Crowchild Trail N.W. Calgary, Canada T2M 3Y7 Telephone: (403) 531-1300 Fax: (403) 289-8502 E-mail: cmgl@cmgl.ca Confidentiality:All components of CMG technology including software and related documentation are protected by copyright, trademark and secrecy. CMG technology can be used only as permitted by your license from CMG. By the license, you have agreed to keep all CMG technology confidential and not disclose it to any third party. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic, mechanical, or otherwise, including photocopying, recording, or by any information storage/retrieval system, to any party other than the licensee, without the written permission of Computer Modelling Group. Corrections/Errors:CMG ENDEAVORS TO PRODUCE TECHNOLOGY OF THE HIGHEST QUALITY; NEVERTHELESS ERRORS OR DEFICIENCIES IN SUCH TECHNOLOGY ARE INEVITABLE. IF YOU FIND AN ERROR OR DEFICIENCY, YOU ARE REQUESTED TO PROVIDE DETAILS OF IT AND ILLUSTRATIVE DATA SET(S) TO CMG SUFFICIENT TO PERMIT CMG TO REPRODUCE THE ERROR OR DEFICIENCY. CMG SHALL ENDEAVOR TO REMEDY A DEFICIENCY IN A TIMELY MANNER AND SHALL PERIODICALLY REPORT TO YOU AS TO THE STEPS BEING TAKEN TO REMEDY THE DEFICIENCY. THE RESPONSE TIME FOR A DEFICIENCY MUST BE PRIORITIZED FOR THEIR GENERAL APPLICATION TO CMG MEMBERS AND WHETHER THEY FORM PART OF A CMG PROGRAM. CMG DOES NOT WARRANT THAT DEFICIENCIES WILL BE REMEDIED. Limited Liability:CMG does not warrant the accuracy or usefulness of the technology and software - Refer to your license. User Guide WinPropContents i Contents New Features1 New Features in WinProp 2014.10 ............................................................................... 1New Features in WinProp 2013.10 ............................................................................... 2Simulator Calculation Engine Changes ........................................................... 2Graphical User Interface Changes ................................................................... 3New Features in WinProp 2012.10 ............................................................................... 3Simulator Calculation Engine Changes ........................................................... 3Graphical User Interface Changes ................................................................... 4New Features in WinProp 2011.10 ............................................................................... 4New Features in WinProp 2010.10 ............................................................................... 5New Features in WinProp 2009.10 ............................................................................... 5New Features in WinProp 2008.10 ............................................................................... 6New Features in WinProp 2007.10 ............................................................................... 6New Features in WinProp 2006.10 ............................................................................... 7New Features in WinProp 2005.10 ............................................................................... 7New Features in WinProp 2004.10 ............................................................................... 8New Features in WinProp 2003.11 ............................................................................... 8New Features in WinProp 2003.10 ............................................................................... 9New Features in WinProp 2002.10 ............................................................................. 10New Features in WinProp 2001.10 ............................................................................. 10New Features in WinProp 2000.15 ............................................................................. 11New Features in WinProp 2000.10 ............................................................................. 12New Features in WinProp 1999.10 ............................................................................. 13New Features in WinProp 98.00 ................................................................................. 16New Features in WinProp 97.00 ................................................................................. 18Introduction21 WinProp Overview ..................................................................................................... 21Use of this Manual ...................................................................................................... 21Installation .................................................................................................................. 22Confidentiality ............................................................................................................ 22Template Data Files .................................................................................................... 22 ii ContentsUser Guide WinProp Basic Operations25 Overview .................................................................................................................... 25Elements of the WinProp Program Window .............................................................. 25Inserting Simulation Steps............................................................................. 26Step Validation Status ................................................................................... 27Including/Excluding Steps ............................................................................ 27Comments ...................................................................................................... 28Accessing On-Line Help ............................................................................................ 28Creating, Opening and Saving Data Files .................................................................. 28Running and Viewing Output ..................................................................................... 29Copying Between Data Sets ....................................................................................... 29Setting Up a Regression Run ...................................................................................... 29Using the Update Component Properties Feature ...................................................... 31Set up the Splitting Calculation: .................................................................... 31Run WinProp ................................................................................................. 31Remove Splitting Node ................................................................................. 31View/Print the Data Set .............................................................................................. 31Editing the Data Set .................................................................................................... 32Operations with Multiple Calculation Modules ......................................................... 32Titles/EOS/Units Selection35 Overview .................................................................................................................... 35Data Input ................................................................................................................... 35Comments ...................................................................................................... 35Title Line 1, Title Line 2, Title Line 3 .......................................................... 35Equation of State ........................................................................................... 36Units .............................................................................................................. 36Feed ............................................................................................................... 36Components37 Component Selection and Definition ......................................................................... 37Library Components ...................................................................................... 38User Component with Known Properties ...................................................... 39Component Properties ................................................................................................ 41Notes on Component Properties .................................................................... 42Interaction Coefficients .............................................................................................. 47Hydrocarbon-Hydrocarbon Interaction Coefficients ..................................... 48Other Interaction Coefficients ....................................................................... 50Viscosity Parameters .................................................................................................. 50J ossi-Stiel-Thodos Correlation ...................................................................... 51Pedersen Correlation ..................................................................................... 52 User Guide WinPropContents iii Aqueous Phase ............................................................................................................ 53Aqueous Phase Salinity ................................................................................. 53Henrys Law Constant Correlation ................................................................ 54Model Option .............................................................................................................. 54Activation of Second Set of Component Properties ................................................... 55GEM Fluid Model Generation and Component Properties Printing ........................... 55GEM-GHG Parameter Selection ................................................................................. 57Common Data Required for All Options61 Overview ..................................................................................................................... 61Composition Specification .......................................................................................... 61Initial K-Values ........................................................................................................... 63Output Level ............................................................................................................... 64Stability Test Level ..................................................................................................... 64Two-Phase Saturation and Phase Boundary Calculations65 Overview ..................................................................................................................... 65Saturation Pressure ..................................................................................................... 65Saturation Temperature ............................................................................................... 66Phase Boundary and Quality Line Calculations ......................................................... 66Envelope Specification .................................................................................. 67Envelope Construction Controls .................................................................... 70Cricondenbar/Cricondentherm Calculation ................................................................ 70Critical Point Calculation ............................................................................................ 71Flash Calculations73 Overview ..................................................................................................................... 73Common Input for Two-Phase Flash, Multiphase Flash and Asphaltene/Wax Modelling Calculations ............................................................................................ 73Two-Phase Flash Calculations .................................................................................... 74Multiphase Flash Calculations .................................................................................... 75Asphaltene/Wax Modelling ........................................................................................ 77Theoretical Background ................................................................................. 77Input Data - Asphaltene/Wax Modelling ....................................................... 78Single-Phase Calculation ............................................................................................ 84Isenthalpic Flash Calculations .................................................................................... 84Theoretical Background ................................................................................. 84Input Data - Isenthalpic Flash ........................................................................ 86Three-Phase Boundary Calculation89 Background ................................................................................................................. 89Input Data ................................................................................................................... 89 iv ContentsUser Guide WinProp Envelope Specification Tab ........................................................................... 89Envelope Construction Controls Tab ............................................................ 91Initial K-Values Tab ...................................................................................... 92Component Splitting and Lumping93 Overview .................................................................................................................... 93Characterization of Multiple Related Samples ........................................................... 94Splitting the "Plus" Fraction ....................................................................................... 94Numerical Cleaning of Mud-Contaminated Samples ............................................... 100Lumping of Components .......................................................................................... 102Transferring Results to Other Data Sets ................................................................... 103Laboratory Calculations105 Overview .................................................................................................................. 105Recombination of Separator Oil and Gas ................................................................. 105Compressibility Calculation ..................................................................................... 108Constant Composition Expansion ............................................................................ 110Differential Liberation .............................................................................................. 113Constant Volume Depletion ..................................................................................... 116Separator Test ........................................................................................................... 120Swelling Test ............................................................................................................ 123Multiple Contact Miscibility Calculations127 Overview .................................................................................................................. 127Data Input ................................................................................................................. 128Regression133 Overview .................................................................................................................. 133Organization of the Input Data ................................................................................. 133Parameter Selection .................................................................................................. 135Grouping Regression Variables ................................................................................ 138Regression Variable Bounds .................................................................................... 140Regression Control Parameters ................................................................................ 142Transferring Results to Other Data Sets ................................................................... 143Compositional Grading145 Overview .................................................................................................................. 145Data Input ................................................................................................................. 146 User Guide WinPropContents v STARS PVT Data Generation149 Overview ................................................................................................................... 149Use of the STARS PVT Generation Option ............................................................. 149Input Data (STARS) ................................................................................................. 150Basic STARS PVT Data .............................................................................. 150Gas-Liquid K-Value Tables ......................................................................... 154Gas-Liquid and Liquid-Liquid K-Value Tables .......................................... 156Gas-Liquid and Solid-Liquid K-Value Tables ............................................. 158Feed and K-Value Plotting Controls ............................................................ 159Black-Oil PVT Data Generation161 Overview ................................................................................................................... 161Laboratory Procedure ............................................................................................... 174Input Data ................................................................................................................. 175References179 List ............................................................................................................................ 179Appendix A183 Case Studies .............................................................................................................. 183Case Study Number 1:Gas Condensate Modeling ..................................... 183Case Study Number 2:Solubility of CO2 in Brine ..................................... 206Case Study Number 3:Asphaltene Precipitation Modeling ....................... 223Appendix B241 Equations .................................................................................................................. 241Cubic Equation of State ............................................................................... 241Phase Stability Test ...................................................................................... 246Two-Phase Flash Calculation ...................................................................... 248Saturation Calculation .................................................................................. 249Cricondenbar/Cricondentherm Equations .................................................... 251Phase Diagram Construction ....................................................................... 251Three Phase Flash Calculation with Equation of State ................................ 255Three Phase with Isenthalpic Flash Calculation .......................................... 257Flash Calculation Involving Water .............................................................. 259Critical Point Calculations ........................................................................... 262Viscosity Correlation ................................................................................... 264Solution of Non-Linear Equations ............................................................... 265Plus Fraction Characterization ..................................................................... 266Interfacial Tension Calculations .................................................................. 270 vi ContentsUser Guide WinProp Regression ................................................................................................................ 270Introduction ................................................................................................. 270The Regression Method............................................................................... 271Application of the Regression ..................................................................... 272Properties of Components ........................................................................................ 275User Components ........................................................................................ 277Interaction Coefficient ................................................................................. 279Nomenclature ........................................................................................................... 281References for Appendix B ...................................................................................... 283 User Guide WinPropNew Features 1 New Features New Features in WinProp 2014.10 Flash Enhancement For performing negative flashes in difficult regions (e.g. near-critical) a new flash method using Newton iteration has been added. This technique is available for the Two-Phase Flash calculation by selecting Negative/Newton as the flash type. A new template data set illustrating use of the option is given in TwoPhase_negativeNewtonFlash.dat. New Phase Split Calculation The phase split calculation of Li, J ohns and Ahmadi (Fluid Phase Equilibria 316 (2012) 85-97) has been implemented for use with multi-contact miscibility calculations, and also with the new flash option described above. This change, and other algorithm enhancements, has improved the efficiency and convergence of the multi-cell mixing method for MMP calculations. STARS PVT generation enhancements The option to specify the pressure-dependent enthalpy model for STARS PVT generation has been implemented. The PVT_DEPARTURE keyword and associated ideal gas enthalpy coefficient data will be written to the STARS fluid model file when this option is selected. The new Negative/Newton flash method described above is also available for generating STARS K-Value tables. A new template data set illustrating use of the option is given in stars_GLKTables_negativeNewton.dat. Improved Property Estimation Ideal Gas Heat Capacity coefficients for components lighter than C6 are now estimated according to molecular weight if these coefficients are not obtained from the component library or entered by the user. This will give improved results for these components compared to using standard correlations. Graphical User Interface Enhancements Experimental data points will now be shown in plots for all calculation options, inside or outside of the regression block. 2 New FeaturesUser Guide WinProp Context menu options for selection of volume shift correlation options have been improved. There is now a Preferences menu item that allows the user to choose which text editor is used when the option to display output data in an external editor is activated. New Features in WinProp 2013.10 Simulator Calculation Engine Changes Linear Temperature-Dependent Volume Shift A linear temperature-dependent volume shift model has been implemented in WinProp. This model is useful for matching density data over a range of temperatures, especially for heavy oils.The temperature-dependent parameter in the model may be adjusted via regression, or estimated with a correlation.This model is also available in GEM. The old temperature-dependent volume shift formulation is still available; however the old model cannot be adjusted in regression and is not available in GEM. STARS PVT It is now possible to specify both Basic STARS PVT and STARS K-value generation in a single calculation option. The previous behavior of running only one of these calculations is still available. Lumping of Non-Adjacent Components The data entry window for the Lumping option has been modified. It is now possible to enter the pseudo-component number for any individual component directly in the lumping scheme table. This allows lumping of non-adjacent components. All existing Lumping data sets will run as before, but will be converted to the new data entry format when opened in WinProp. Phase Diagram for Pure Component It is now possible to generate a pure component Pressure-Temperature diagram (vapor pressure curve) using the Two-Phase Envelope calculation option. No changes in input are required. This feature will be active if only one component is defined, or if only one component in a multi-component system has a non-zero composition. New Phase Property Plots Phase Enthalpy, Heat Capacity and Entropy are now available to be plotted via the Plot Control tab for the two-phase flash, multiphase flash and multi-phase with solid flash. Other Changes Default binary interaction parameters and volume shifts have been modified for some library components, particularly for the SRK EOS. User Guide WinPropNew Features 3 Excess enthalpy, heat capacity and entropy may be calculated using the Lee-Kesler EOS/corresponding states model, to allow comparison of this model to excess properties calculated directly from the cubic EOS. Graphical User Interface Changes Multiple Components Deletion From the component GUI, multiple components can be selected (i.e. row-wise) and deleted. Single Component Duplication With Copy and Paste buttons, a single component can be easily duplicated. Cleaner Component GUI Action buttons for setting Volume Shift and Reference Henry Constant are replaced with the relevant context menus, which can be executed via the corresponding property column header. Plot Data Export The functionality for exporting plot data to TXT or XML has been completed allowing the export of all plot data for all calculation options, export of all plot data for one calculation option, or export of plot data for one plot. New Features in WinProp 2012.10 Simulator Calculation Engine Changes STARS Gas Viscosity Parameter Generation The STARS Basic PVT calculation now has the option to write out component gas viscosity correlation coefficients. Since the STARS gas viscosity model is a low-pressure form, the coefficients are generated at atmospheric pressure. See template data set stars-gas_visc_withH2O.dat. Multiple Mixing Cell Method for MMP The multiple mixing cell method of Ahmadi and J ohns (SPE 116823) for calculating minimum miscibility pressure has been implemented in WinProp. Recent research on analytical method-of-characteristics (MOC) techniques for calculating MMP indicates that the MOC methods may not always converge to the correct solution. The multiple mixing cell method is included as an alternative to check the results of MOC calculations, and possibly indicate if slim-tube simulations should be done. Additional Regression Variables for OGW Flash The component mole fractions in non-aqueous phases and component gas-water and oil-water k-values can now be specified as experimental data for regression in the OGW flash. 4 New FeaturesUser Guide WinProp Enthalpy and Entropy Calculations Phase Entropy is now output in the standard phase property table in WinProp, along with enthalpy and heat capacity. The database of ideal gas enthalpy coefficients used in the calculation of all of these quantities has been updated from the 2005 edition of the API Technical Data Book, to eliminate some inconsistencies in the earlier data. Format I and Format II Extended Black Oil Tables The calculation of the alternate format extended black oil tables has been enhanced for better consistency with Equation-of-State results for density and viscosity. Graphical User Interface Changes Operations with Multiple Calculation Modules A new dialog has been implemented to allow operations to be performed on multiple calculation modules simultaneously. The dialog shows a list of the calculation modules in the data set that can be selected using the usual and keyboard controls. The selected items can be included/excluded from the WinProp run, or cut/copied to the clipboard. The contents of the clipboard may then be pasted into any open data set. Other Interface Features An option to temporarily disable regression has been implemented. The calculations in the regression block are still performed, but no regression is done. New Features in WinProp 2011.10 Re-designed Graphical User Interface The main program window for WinProp has been completely redesigned, greatly improving the functionality and ease of use of the interface. The data entry windows for the calculation options are very similar to previous versions of the program, allowing existing users to quickly become familiar with the new software. Please see the Basic Operations chapter for a description of the new interface and how to use it. New features of the interface include: The structure of the data set (order of calculation options) is now displayed in a tree view, as opposed to the table -of-contents style grid. All data entry windows are displayed within the main program interface. For QC checks, plots are shown within the data entry windows of component properties vs. molecular weight, as well as plots of experimental data vs. pressure for CCE, CVD and DifLib laboratory experiments. Text and graphical output is now displayed within the main program window, accessed via the tree view. User Guide WinPropNew Features 5 Text output can be sent to Windows Notepad, and graphs can be printed, copied to the clipboard, saved as a jpg file or graph data can be exported as a text file. The Table Import Wizard is now obsolete, as tabular data can be pasted directly from spreadsheets into the data entry grids for laboratory PVT experiments. For component properties definition, the user-component data entry dialog has been expanded to include the functionality of the Table Import Wizard, allowing specification of properties for multiple components in one step. New Features in WinProp 2010.10 New Approach for the Multiple Contact Miscibility Calculation A Tie Line calculation method has been added to WinProp in the Multiple Contact Miscibility Calculations chapter to calculate the minimum miscibility pressure (MMP) or minimum miscibility enrichment (MME). This method takes the combined condensing and vaporizing displacement mechanisms into consideration, as well as the existing pure vaporizing or pure condensing mechanisms. With the pressure or enrichment increasing, all key tie lines, including the initial tie line, injection tie line and the crossover tie lines, can be found simultaneously based on the method of characteristics theory. The MMP or MME can be determined once any of these key tie lines length becomes zero. See the Multiple Contact Miscibility Calculations chapter for more details. Use of the feature is illustrated in the mcm-combined-U2002rich-MMP.dat template data set. Liquid Viscosity-Temperature Table for Multiple Pressures The STARS PVT generation option can now calculate and output multiple liquid viscosity-temperature tables over a defined pressure range. This is compatible with a new STARS option to allow pressure dependence of liquid viscosities available in STARS 2010.10. New Features in WinProp 2009.10 Numerical Cleaning of Mud-Contaminated Samples A new feature has been added to WinProp in the Component Splitting and Lumping chapter. WinProp now can determine the original composition of the reservoir fluids from mud-contaminated samples. WinProp uses the skimming method, subtraction method or a combination of both methods to numerically clean the mud-contaminated samples. If the level of mud contamination is available and the mud composition is also provided, a direct subtraction method will be used to numerically clean the contaminated sample. If the level of mud contamination is not available but the mud composition is provided, a combination of the skimming method and subtraction method will be used to estimate the level of contamination first, and then numerically clean the contaminated sample. If there is no information about the level of contamination and mud composition, WinProp can use skimming method to numerically clean the contaminated sample based on the first and last SCN in the mud. Please see the Component Splitting and Lumping chapter for more details. Use of the feature is illustrated in the mudclean_split.dat template data set. 6 New FeaturesUser Guide WinProp New Features in WinProp 2008.10 STARS PVT Generation A number of enhancements have been made to improve the liquid density parameters. The feed composition is flashed at reference pressure and temperature so that a stable liquid composition is used for all calculations. Once this is done, Compressibility, first and second thermal expansion coefficients are determined froma perturbation calculation. Finally the cross coefficient (P and T) is determined by optimization to best fit surface conditions and a user-specified range of reservoir condition densities. These changes result in a decreased sensitivity to the choice of reference conditions, more accurate compressibility parameters, and a better match between the EOS and STARS fluid model densities, which are now shown in a table in the .out file. The reference phase for components can now be specified as AQUEOUS, the previous default was that all components are OLEIC. This means that K-values for gas-water systems can be generated. In addition, the solid K-value table generation has been improved, as well as the map of WinProp EOS vs. STARS k-value flash results. Aqueous Phase Property Models Accurate models for the Henrys constants of CO2, N2, H2S and CH4 have been implemented, taking into account pressure, temperature and salinity (salting-out coefficient). These models are activated by selecting the option button for Harveys Method (1996) on the Aqueous phase tab of the Component properties dialog. These correlations are also implemented in GEM 2008.10. The existing aqueous phase solubility models are still available in WinProp. The Kestin correlation is now used for aqueous phase viscosity when the OGW flash is specified in WinProp. Calculation of Temperature-Dependent Asphaltene Parameters It is now possible to enter multiple asphaltene onset pressures at different temperatures in the asphaltene flash dialog. These values are used to calculate the temperature-dependent parameters of the asphaltene precipitation model. New Features in WinProp 2007.10 IMEX Volatile Oil PVT Table Generation Black oil PVT tables can be generated for the new IMEX volatile oil option. Undersaturated gas compressibility and viscosity may be represented using only the dry gas and saturated gas endpoints, or with a complete table of values between these endpoints. The endpoints form uses the new PVTVO table. To allow modeling of nonlinear effects in the gas compressibility and viscosity, undersaturated gas property tables are used in conjunction with the PVTCOND table, as for the Gas-Water with Condensate model in IMEX. User Guide WinPropNew Features 7 Other Enhancements for IMEX PVT Table Generation For all IMEX PVT tables, the user can now choose to generate gas formation volume factors, gas expansion factors, or gas Z-factors. This applies to the saturated tables (PVT, PVTG, PVTCOND and PVTVO) as well as the undersaturated gas tables, which can now take the form BGUST, EGUST or ZGUST. For IMEX PVTCOND and PVTVO tables, calculation of the condensate/gas ratio at low pressures has been modified for improved performance in the simulator. Scaling Differential Liberation Oil FVF and GOR to Bubble Point Oil Volume For the differential liberation experiment, oil formation volume factor and solution gas/oil ratio can be scaled to the bubble point oil volume rather than the residual oil volume. This provides oil shrinkage and cumulative gas released per volume of bubble point oil, and eliminates the need for the EOS to accurately represent the residual oil volume. The scaled values can be used in regression. Summary plots show both the original data and the scaled values. STARS PVT Generation For STARS PVT generation, new methods have been implemented to generate the component liquid viscosity table. Apparent liquid viscosities of light components can be generated by perturbing the dead oil at each temperature, which will give accurate liquid viscosities of solvent components which may vaporize at higher temperatures ("match dead oil" method). Smooth curves for all component viscosities may be generated by scaling the liquid viscosities at low temperatures, then extrapolating to higher temperatures ("scale viscosities" method). More accurate determination of phase viscosity and density, and reduced sensitivity to choice of reference condition, have been achieved by using stable liquid properties in STARS component property calculations. Saturation Pressure/Regression Enhancement Saturation Pressure calculation results are checked for stability. This prevents the regression algorithm from converging to an unstable two-phase saturation condition, within a three-phase region. New Features in WinProp 2006.10 Enhancements of existing features and code clean up. New Features in WinProp 2005.10 A number of WinProps calculation options have been enhanced, including the following: Irreversible Asphaltene Calculation The asphaltene flash has been enhanced to allow specification of an equilibrium constant for conversion of reversible to irreversible asphaltene. The irreversible asphaltene can be interpreted as flocculated solid particles. This technique has been designed to allow the simulation of laboratory forward and reverse contact experiments with series of asphaltene flash calculations. 8 New FeaturesUser Guide WinProp Oil-Gas-Water (OGW) Flash Calculations The OGW flash has been improved to give greater stability and better convergence characteristics for difficult problems, for example light and intermediate hydrocarbons with steam. STARS Aqueous-Liquid and Aqueous-Vapor K-Value Generation In addition to the improvements of the OGW flash listed above, the generation of STARS K-values including aqueous phases has been enhanced with improved extrapolation algorithms. New Features in WinProp 2004.10 A number of WinProps calculation options have been enhanced, including the following: Compositional Gradient Calculation For the non-isothermal model, temperatures are now output to the summary table, error trapping has been improved, and the input of the temperature gradient has been modified so that positive gradient values now indicate increasing temperature with depth. Viewing Simulator PVT Models Menu items have been added to allow easy viewing of the files generated for GEM, IMEX or STARS component models, analogous to the WinProp output file viewing procedure. Temperature-Dependent Volume Shifts The Racketts Z-Factor is now re-calculated during lumping or regression calculations, so that the temperature-dependent volume shift technique will maintain consistency with pseudocomponent specific gravities. STARS PVT Model Generation Liquid-phase component viscosities for light components are now back-calculated from live oil and dead oil viscosities, rather than computing them directly from the WinProp viscosity model. New Features in WinProp 2003.11 Gamma Distribution Characterization Enhancements The following enhancements have been implemented for the gamma distribution characterization: (1) Specification of the bounds on the molecular weights has been improved when using the variable molecular weight interval method for fitting the distribution parameters to extended analysis data. (2) When specific gravity data is available with the extended analysis, coefficients in the specific gravity-molecular weight correlation are adjusted to best fit the data. (3) Use of the gamma distribution to extrapolate extended analysis data to higher carbon numbers has been improved to provide better consistency with input physical property data. User Guide WinPropNew Features 9 Separator Calculation for Gas Condensates Calculation of dry gas and wet gas formation volume factors has been implemented when the separator calculation is used with gas condensate fluids. The dry gas FVF is defined as the volume of gas at the dew point pressure divided by the volume of gas from all separator stages evaluated at standard conditions. The wet gas FVF is defined as the volume of gas at the dew point pressure divided by a hypothetical surface wellstream volume, calculated under the assumption the entire wellstream is in the gas phase with a Z-factor of one. The condensate/gas ratio is also reported. In addition, the average separator gas gravity from all separation stages is now being output for oil and condensate fluids. New Features in WinProp 2003.10 IMEX GASWATER_WITH_CONDENSATE PVT Table Generation The black oil PVT option has been expanded to allow generation of PVT tables for the IMEX GASWATER_WITH_CONDENSATE fluid model. This model allows description of condensate liquid dissolved in the gas phase or present as a free liquid in the reservoir and at surface conditions. This option may be used for dewpoint fluids (gas condensates) only. The tables are generated by simulating a constant volume depletion experiment. For each pressure level in the constant volume depletion, a row in the *PVTCOND table for the saturated properties is written. Individual *BGUST and VGUST tables are written for the gas formation volume factors and gas viscosities corresponding to each saturation pressure in the *PVTCOND table. Use of the feature is illustrated in the imex_condensate.dat template data set. Regression on Secondary Stream Mole Fraction The ability to select the mole fraction of the secondary stream, used to define the feed composition for a calculation option, has been added to the regression calculation. The feed composition can be defined as a mole fraction weighted mixture of the primary and secondary compositions. This mole fraction can be adjusted during regression to match any of WinProps allowable experimental data types. One application of this feature is to determine the mole fraction of a separator gas streamnecessary to recombine with a separator oil stream to achieve a specified GOR. Use of this feature is illustrated in the template data set regress_stream-frac.dat. Automatic Selection of Regression Parameters For users with limited experience in tuning equation of state parameters to match experimental data, a facility is provided to automatically select regression parameters based on the types of experimental data entered in the calculation options within the regression block. WinProp will select a combination of critical properties of the heavy end pseudocomponents, volume shift parameters, hydrocarbon binary interaction parameter exponents and viscosity parameters to be adjusted during regression, depending on the experimental data entered. The automatic parameter selector will not remove any parameters already selected by the user. Also, once the automatic parameter selection process is complete, you may add or remove regression parameters manually. 10 New FeaturesUser Guide WinProp New Features in WinProp 2002.10 Minimum Miscibility Enrichment Level A minimum miscibility enrichment level option has been added to the multi-contact miscibility calculation. This feature allows calculation of the minimum fraction of rich gas required to be added to a lean gas stream to achieve multi-contact miscibility with an oil at a specified pressure. A minimum rich gas fraction and a number of gas fraction steps are specified. WinProp performs multiple-contact calculations for each step in the rich gas fraction, and interpolates to determine the minimum enrichment level for multi-contact miscibility. Results of the calculations for each solvent gas mixture tested are displayed on ternary diagrams. This feature is an addition to the existing multi-contact calculation for determination of the minimum miscibility pressure for a given oil and solvent. K-Value Plotting The phase property plotting feature has been enhanced to allow generation of K-value plots for the 2-phase flash, multiphase flash, and the STARS K-value calculation options. Gas-Liquid, Liquid-Liquid and Aqueous-Liquid K-value plots may be generated. The results are shown as the log of the K-value for each component, plotted against pressure, temperature or composition, depending on which independent variable has been specified for the flash. STARS Fluid Model Generation Enhancements The options for treatment of surface streams for STARS production reporting can now be specified in WinProp. This includes specifying the surface pressure and temperature, the flash options *SEGREGATED or *KVALUE and also the new option for specifying K-values which are used only for the surface flash. The ability to specify these K-values separately from the K-value tables allows the pressure and temperature range for the tables to be concentrated on the expected reservoir conditions, but still calculate accurate surface phase splits. Both Gas-Liquid and Liquid-Liquid K-values at the surface can be specified. The extrapolation algorithm for determining component K-values outside of the range of convergence of the flash calculations has also been improved. New Features in WinProp 2001.10 Thermal Compositional Gradient Model Beginning with the 97.00 release, WinProp has had the capability to perform isothermal gravity/chemical equilibrium calculations for the determination of compositional grading due to gravity. The 2001.10 release includes the option to incorporate thermal effects on the gradient calculation. The model equations are developed based on the zero mass flux condition. Calculations may be performed without thermal diffusion (passive thermal gradient case) or with thermal diffusion coefficients determined from correlations or entered as constant values for each component. User Guide WinPropNew Features 11 New Features in WinProp 2000.15 STARS PVT Data Generation Enhancements A number of features for creating STARS component property and K-value data have been added to WinProp. For component properties the following features have been implemented: optional use of WinProps viscosity model for component viscosities as opposed to the corresponding states model, optional output of viscosity versus temperature table instead of correlation coefficients, and the generation of viscosity and density nonlinear mixing functions. For K-value data, the features added include: generation of liquid-liquid and gas-liquid K-value tables simultaneously, generation of composition dependent K-value tables, use of STARS defaults for water K-values, indication of which K-values have been extrapolated in the tables, and output of a map comparing the WinProp calculated phase split to that determined from the K-value tables. Please see the STARS PVT Data Generation chapter for more details. WinProp-ModelBuilder Integration Several features have been introduced to enhance the data flow between WinProp and ModelBuilder. The concept of PVT Meta-Data has been introduced; this refers to the equation of state model and mixture composition used to generate the PVT data for IMEX or STARS (for GEM, the equation of state model used is the same as in WinProp, so Meta-Data is not required). In this release of WinProp, the PVT Meta-Data will be written out to the file with the IMEX fluid model. When this file is imported into ModelBuilder, the Meta-Data will be read in and stored in the simulator data set. If it is desired at a later date to analyze or modify the PVT data in some way, WinProp can be launched from within ModelBuilder and the Meta-Data EOS description will be restored to WinProp. The GEM EOS model can also be sent to WinProp by launching from within ModelBuilder. In this case, compositions determined from the initial conditions section will be transferred to WinProp as well. Additional PVT Tables An alternate format for black oil PVT tables has been added to the existing options for creating various IMEX or extended black oil PVT tables. The alternate format includes writing of the PVT table in order from highest to lowest pressure, and writing out a table of multiplying factors for the undersaturated oil compressibilities and viscosities. Enhancements to the extrapolation methods for generating PVT properties above the original saturation pressure of the oil have also been implemented. Laboratory Experiment Enhancements The maximum number of separators which may be specified with the constant volume depletion experiment and also for the black oil PVT data generation option has been increased to 8. Liquid dropout for the constant composition and constant volume depletion experiments can now be specified as a percentage of the cell volume at the saturation pressure, or as a percentage of the cell volume at the current pressure step. 12 New FeaturesUser Guide WinProp Interface Enhancements The differential liberation and constant volume depletion experiment data entry forms have been redesigned to allow entry of pressure step data in row format, for improved compatibility with experimental PVT reports. Data for material balance and consistency check calculations is now entered on a separate table which is linked to the main table with the pressure information. Pasting of data to any grid which allows a variable number of rows has been modified to automatically increase the number of rows in the table if required to hold all of the data being input. New Features in WinProp 2000.10 Automatic Generation of Quality Lines on Phase Diagrams A feature has been added to the 2-phase envelope calculation option to allow the user to select lines of constant mole or volume fraction to be calculated and displayed on the plot of the phase envelope. In addition the algorithm has been improved so that the initial guess for the starting point is generated internally. The user no longer needs to initialize phase envelope calculations with a flash or saturation pressure calculation or provide a good guess for the starting point directly. It should now be possible to generate a 2 phase pressure temperature envelope with default selections reliably. Additional PVT Tables For CMGLs IMEX simulator, WinProp can now generate Gas-Water PVT tables. Extended Black Oil type PVT tables can be generated including the Rv data describing oil solubility in the vapor phase. These data are generated by simulating a constant volume depletion or a differential liberation laboratory experiment. Oil properties are obtained by material balance calculations or directly through EOS separator calculations. A number of methods are available for extrapolating individual curves beyond the original saturation pressure. These tables are output in a generic format. The user can then customize this data for use with specific extended black oil reservoir simulation programs. Additional Experimental Data The constant composition expansion experiment option has been enhanced to allow regression on the following experimental data: viscosity, density, compressibility factor and single phase oil compressibility. These data are included in the regression only when the corresponding property can be calculated by the program. For example single phase oil compressibility data will not be used in regression for a dew point fluid. Asphaltene Precipitation Modelling Case Study A new case study is included in the User Guide and on-line help which describes the development of a model for prediction of asphaltene precipitation from a black oil under pressure depletion. The case study illustrates characterization of the oil, regression to match fluid phase behavior data, specification of the asphaltene model parameters, and calibration of the model with experimental precipitation data. User Guide WinPropNew Features 13 All of the case studies are now included in Appendix A. Interface Enhancements A feature has been added to allow calculation options to be temporarily excluded from the data set, rather than deleting them entirely. Options are excluded/included from the main control form by right-clicking on the desired row and making a selection from the pop-up menu. One application of this feature is to temporarily reduce the number of calculation options within a regression block to try and obtain a match to some key data. After an initial regression run, the component properties can be updated and calculation options that were excluded can be included again for further regression runs. Data entry and navigation on the grids has been improved by enabling use of the left and right arrow keys, in addition to the up, down and enter keys. New Features in WinProp 1999.10 Enhancements to Aqueous Phase Solubility Calculations WinProp supports calculation of solubility of light gas and hydrocarbon components in the aqueous phase using Henrys law. This feature is enabled by selecting flash type OGW (Oil-Gas-Water) on the OGW/EOS Multiphase Flash form. Henrys law constants can be entered by the user or calculated internally using correlations fit to experimental solubility data. Two new features have been added for modeling aqueous phase solubility. First, modification of the internally calculated Henrys constants to account for salinity of the aqueous phase has been implemented. By default, the internal Henrys constants are for pure water. To predict solubility of components in brine, all that is required is brine salinity, in terms of equivalent NaCl concentration. This is entered on tab Aqueous phase of the Components Selection/Properties form. The second feature implemented is regression on the aqueous solubility parameters to match experimental solubility data. Component reference Henrys constants, i.e. Henrys constant at a specified reference pressure, and molar volume at infinite dilution can be adjusted to match experimental data. Please see the Components chapter for further description of Henrys constants. Case Study Number 2:Solubility of CO2 in Brine illustrates the use of both of these new features. Pedersen Viscosity Correlation WinProp now allows use of the Pedersen corresponding states viscosity correlation in addition to the J ossi-Stiel-Thodos (JST) correlation. The Pedersen correlation is expected to give better liquid viscosity predictions for light and medium gravity oils than the J ST model. The Pedersen correlation is not dependent on having accurate density predictions as the J ST technique is. Parameters in either correlation may be adjusted during regression to match experimental viscosity data. Please see the Components chapter for more information on viscosity models. 14 New FeaturesUser Guide WinProp Generation of PVT Properties for CMGs IMEX Simulator WinProp can now generate the PVT data corresponding to the light oil and the pseudo-miscible models of CMGs IMEX simulator. Earlier releases targeted the black oil model only. In addition, the aqueous phase properties can now be estimated from built in correlations as an alternative to entering the values directly. The PVT fluid model data with the associated IMEX keywords is written to an output file with the extension (.imx). This file can be referenced as an include file in an IMEX data file. Please refer to the Black-Oil PVT Data Generation chapter of this manual for a complete discussion. Consistency Checks and Material Balance Calculations A number of tools are available in WinProp for evaluating the quality of PVT data provided to the reservoir engineer from laboratory or field measurements. The data is typically used to tune the EOS model. It is imperative therefore that the PVT data is analyzed critically prior to any detailed regression calculations. The tools available include Hoffman plots and material balance calculations. Material balance calculations for the constant volume depletion (CVD), differential liberation (DL) and separator options are performed if the required data is entered. For these experiments, the required data are generally reported in a typical PVT report from a laboratory. A Hoffman plot is generated for the recombination option based on the entered oil and gas compositions. Hoffman plots are also created with the CVD, DL and separator options if sufficient data is entered to calculate the oil phase compositions from a component material balance. Refer to the Laboratory Calculations chapter for more detail as well as template cases matbal-bo.dat and matbal-gc.dat. Changes to the Multiple Contact Miscibility (MCM) Option A number of enhancements have been made to the MCM option with the objectives of 1) alleviating difficulties in interpreting the program results and 2) determining and reporting multiple and first contact miscibility pressures directly. With respect to point one, the criteria used for stopping the forward and backward contact flash calculations are reported in the output file. The most likely reasons are either miscibility is achieved or there is no change in the oil and gas compositions from the previous contact. With respect to point two, the user can now enter a range of pressures for the calculation. If multiple and/or first contact miscible pressure(s) are found in this pressure interval then these values are reported at the end of the output listing. Ternary diagrams are also automatically created at designated intervals. Specification of Mole Fraction Steps for Flash Calculations The ability to specify steps in the primary mole fraction making up the feed to a flash calculation has been implemented for two-phase, multiphase and asphaltene/wax flash calculations. This allows the specification of flashes for a number of mixtures of the primary and secondary compositions on a single flash form. This feature is similar to the existing capability for specifying pressure and temperature steps. These steps can be defined with the feed specification on the first tab of each flash calculation. User Guide WinPropNew Features 15 Plotting Capability Added to Two-Phase and Multiphase Flash When a series of flash calculations have been specified by setting temperature, pressure or mole fraction steps, plots of the phase properties can be generated. Up to three phase properties, such as molecular weight, compressibility factor or phase mole fraction, can be selected for each flash calculation. One plot is generated for each property and each phase. When plotting is activated, steps can be specified in one or two of the variables: pressure, temperature and mole fraction. If steps are specified for only one variable, the plots are generated with that variable as the independent variable, and the phase property as the dependent variable. Up to 100 steps in the independent variable are allowed. When steps are specified for two variables, one variable is treated as a parameter variable, and curves of the phase property are displayed for each value of the parameter variable. Up to 8 steps in the parameter variable are allowed. The phase properties to be plotted are selected on tab Plot Control of the flash calculation forms. Plotting Capability Added to Asphaltene/Wax Flash The asphaltene/wax flash has a plotting feature similar to the one described above for the two-phase and multiphase flashes. This allows generation of plots such as weight % precipitate as a function of solvent concentration or pressure. A special plotting feature implemented for the asphaltene/wax flash is the generation of a pseudo-ternary diagram to display the results of flash calculations in terms of the predicted phase split, i.e. liquid-vapor, solid-liquid etc. The results are shown for a number of dilution lines defined by the user. Plot specification is done on tab Plot Control of the asphaltene/wax flash calculation. Three-Phase Envelope Automatic Plot Generation Automatic plot generation has been implemented for the three-phase boundary calculation. Excel plots can now be created for three-phase P-T, P-X and T-X diagrams. These plots can be created by selecting File | Create Excel plots after running a data set with a three-phase envelope calculation option. Ternary Diagram Two-Phase Envelope Generation The capability to create ternary or pseudo-ternary two-phase boundaries has been added to the two-phase envelope calculation option. This calculation locates points in composition space defining the two-phase vapor-liquid phase boundary on a triangular diagram. This can be considered a static or single-contact calculation, as opposed to the multiple contact calculation option which performs a dynamic simulation of multiple contact miscibility processes. This feature is enabled by selecting Pseudo-Ternary Phase Envelope on the Two-phase envelope calculation option form. Table Import Wizard A Table Import Wizard has been implemented in WinProp to assist the user in importing data into WinProp from existing Excel or ASCII format files. The wizard guides the user through the steps of selecting data to be imported, defining units and performing unit conversions, and 16 New FeaturesUser Guide WinProp inserting the imported data into the correct locations in WinProps data structure. Table import is available for the following forms: Component Selection/Properties, Plus Fraction Splitting, Constant Composition Expansion, Differential Liberation, Constant Volume Depletion and Swelling Test. An example illustrating the use of the Table Import Wizard is given in the Tutorial section of the manual. Information regarding the specific implementation for the forms listed above may be found in the Components, Component Splitting and Lumping, and Laboratory Calculations sections. Interface Enhancements Two toolbars are provided for easier access to items previously available through the menus alone. The main toolbar contains buttons corresponding to items in the File and Edit menus. This toolbar targets frequently performed tasks such as opening and saving files, generating the results, viewing the output file and creating plots. This toolbar is not customizable and is permanently displayed. A second toolbar contains buttons corresponding to often used calculation options. These buttons are grouped to mirror the organization of the menus. This toolbar is customizable. The user can remove any of the buttons selected by default and add buttons corresponding to options not originally chosen. Once the toolbar is customized the settings are saved for subsequent sessions. The options toolbar can also be removed from the interface and reinstituted at a later time. The menu system is revised with the objective of creating more intuitive classes. Similarly, the names of the forms corresponding to the calculation options are modified to be more descriptive. Forms for the constant volume depletion, separator test and differential liberation are redesigned in light of the additional data that can now be entered for material balance calculations. Other enhancements include the addition of progress bars in specific situations. A progress bar is shown when loading or saving the component form for example. New Features in WinProp 98.00 Additional Methods for Heavy Fraction Characterization The three-parameter gamma distribution is now available in WinProp to describe the molecular weight versus mole fraction relationship for the heavy fraction of a petroleum fluid. The Gaussian quadrature method is used in evaluating the integral of this distribution function. The molecular weight of the pseudo components selected corresponds to the quadrature points. Good VLE results are obtained with this method with a small number of pseudo components. In addition the Gamma distribution and Gaussian quadrature can be used to generate a single set of pseudo components for multiple related samples with different plus fraction molecular weight and specific gravity. Related mixtures have the same compounds but in varying proportions, for example saturated oil and its equilibrium gas or fluids from different depths in a reservoir with a compositional gradient. Parameters of the Gaussian distribution function are obtained by nonlinear regression if extended analysis data is entered or fromgeneralized correlations if only plus fraction specific gravity and molecular weight are available. Where multiple samples are involved each sample can have extended analysis data entered if available. Please refer to the Component Splitting and Lumping chapter of this manual for a more extensive discussion. User Guide WinPropNew Features 17 Generation of PVT Properties for IMEX Black Oil Model WinProp can now generate the PVT data corresponding to the black oil model of CMGs IMEX simulator. This data is written out to an output file with the extension blk. This file can then be referenced as an include file in an IMEX data file. The properties of the oil phase (formation volume factor, gas oil ratio) are generated by flashing the equilibrium liquid at each stage of the differential liberation directly through the user specified separator train. The range of the PVT table can be extended to include pressures above the original oil bubble point pressure by generating the swelling curve. This way the table can handle variable bubble point scenarios arising for example from gas injection or solution gas migration followed by re-pressurization. This option can be found under Options | "Black oil model PVT data." Please refer to the Black-Oil PVT Data Generation chapter of this manual for a complete discussion. Process Flow and Isenthalpic Flash Options Data entry forms for the Process flow and Isenthalpic flash options have been added to WinProp. The process flow option can be added to the data file by selecting Calculations | Process flow from the menu and isenthalpic flash by selecting Calculations | Isenthalpic flash. For the process flow sample template are process1.dat, process2.dat and process3.dat. For isenthalpic flash the sample templates are isenth1.dat, isenth2.dat and isenth3.dat. Please refer to the chapter titled Process flow for detailed discussion of the process flow option and the Flash Calculations chapter for more details on the isenthalpic flash option. Support for Multiple Hydrocarbon-Hydrocarbon Binary Interaction Exponents Hydrocarbon components are identified by a value of 1 on the HC column of the component table on the Component form. Binary interaction coefficients between two hydrocarbon components are calculated from a correlation, which involves the critical volume of each component and an exponent parameter. In contrast to previous versions of WinProp where all HC-HC binaries were calculated based on a single exponent parameter, the user can now group pairs of binary and specify a different exponent parameter value for each group. These individual group exponents can be also selected as regression parameter(s). Please see the Components and Regression chapters for more details. Handling of the Regression Block in a Data File In WinProp the regression block refers to the calculation options that are between the Regression and Start regression forms. For a case to run successfully all options in this block must have at least one piece of experimental data entered and all options outside the regression block are required not to have any experimental data entered. WinProp will now attempt to ensure that these requirements are met when the user attempts to run a given case while preserving the data that has been entered. For example if there an option within the regression block then this option will be moved out of the regression block. If there is an option with experimental data outside the regression block then the experimental data will be written out to the data file with the accompanying keyword(s) commented out. This will also allow the user to retain the experimental data that were entered for regression when regression is removed from the data file, that is Regression and End regression 18 New FeaturesUser Guide WinProp forms are removed. The entered experimental data will be shown where appropriate with the program predictions on plots even if there is no regression involved in the run. Interface Enhancements The list of the five most recently files accessed by WinProp is now available on the File menu. This is a faster way of selecting a case than through the file open dialog box. Interface enhancements include the ability to redirect the screen diary to an output file. To redirect select Redirect to file DBPROP.XXX under File | Screen menu. The user can now select an editor other than Notepad by invoking the Editor | User editor select option under the File menu. This will open a file dialog box. Using the file dialog select the executable file corresponding to the desired editor. WinProp allows up to open up to 8 different cases (data files) to be open simultaneously, primarily to allow various calculation option forms to be copied between different data files. This saves the user from having to type in data values multiple times. The MDI capability also facilitates comparing the data entered for a given form across data files. A number of checks have been implemented to avoid violating the internal design limitations of this option. For example forms can be opened only when a single case is loaded and a case cannot be closed until all the open forms are closed. In previous versions of WinProp the data in a table (grid) could be changed via a text box positioned outside the table. With WinProp 98.00 a floating text box positioned exactly on the desired cell is used for table (grid) edits. To erase the current value or text in a cell and enter a new value or text, position the cursor on that cell and start typing. To edit the contents of a cell, position the cursor on that cell and double click with the left mouse button. The cell contents are updated when the carriage return (Enter) key is pressed or if the cursor is moved to another cell. Please note that changing the focus to a new control will not update the grid (table) contents. New Features in WinProp 97.00 Compositional Grading Calculations Significant compositional variation with depth can occur in deep reservoirs with near critical fluids or for fluids where there is a large variation in molecular weight between the light and heavy constituents. This effect is important in estimating materials in place as well as field development and operation strategy. WinProp now has the capability of simulating this phenomena based on the isothermal gravity/chemical equilibrium (GCE) formulation. This option can be found under Calculation Options | Compositional Gradient. A complete discussion can be found in the Compositional Grading chapter. Generation of PVT Properties for STARS STARS is CMG's steam and additive thermal simulator. WinProp can generate the complete PVT data required by STARS. This includes component partial densities, compressibility and thermal expansion factors as well as liquid component viscosity coefficients. WinProp can also generate tabular K-value data between any two phases that STARS supports. STARS used K-values to determine the number of phases in equilibriumand the composition of each phase. The PVT data is printed in a format suitable for direct inclusion in a STARS data file. The output of User Guide WinPropNew Features 19 this option is directed to a file with a suffix .tbl. This option can be found under Options | Print STARS PVT Table. Please refer to the STARS PVT Data Generation chapter of this manual for a more extensive discussion. Regression Enhancements It is now possible to specify more than one component for a given property such as the critical pressure as a single variable in regression. The members of the group will in general have individual initial values and bounds. In regression the same increment is applied to all members of the group. This feature can be useful if it is desired to maintain a certain trend or symmetry for a given property or in avoiding regressing on a property belonging to a component with a small mole fraction. For information on how to define group variables refer to the Regression chapter of this manual. Summary plots showing before regression, after regression and experimental data are now generated automatically when Excel plots are created from a regression run. Individual plots showing calculated results are still available, with new titles indicating before or after regression calculations. Conversion from CMGPROP to WinProp Format A conversion utility is provided within WinProp to translate files created for CMGPROP on UNIX or PC platforms. This utility can be invoked by selecting Options | Convert from Cmgprop to WinProp. The user is advised to open each form and verify the results of the conversion carefully. Please use the Save As option under the File menu to save the WinProp compatible data file to avoid overwriting the original CMGPROP data file. The original file will be an important aid in case difficulties are encountered in conversion and in verifying the conversion. There are a number of situations that can pose difficulties for the converter including the use of wildcards in specifying array values and presence of comment marker on a line where array values are stipulated. Please edit the CMGPROP data file eliminating these situations prior to using the conversion utility. MDI Capability The Multiple Document Interface (MDI) Feature is now implemented in WinProp. This allows the user to open up to eight files at once. This has significant advantages for example when the user desires to compare output files for two or more cases or in the ease with which data corresponding to various calculation options may be copied between different data files. Refer to the Copying Between Data Sets section in the Basic Operations chapter of this manual. Update Component Properties Feature Upon completing a splitting, lumping or regression calculation where the number of components are changed or the component properties modified, WinProp writes out the revised component information in an output file with the suffix .rls. With the previous version of WinProp the user would run a file, for example test1.dat with a splitting calculation, use File | Open to open test1.rls, use File | Save As to rename to test2.dat for example and then continue working with this file by appending calculation options to it. This procedure is now automated with the introduction of the update component properties selection under the Options menu. The user still runs the splitting calculation with test1.dat. Once the calculation is 20 New FeaturesUser Guide WinProp carried out, update component properties is invoked. This updates the information on the Composition and Component forms. The user then removes the splitting calculation from the data file and appends the desired calculation options. Optionally the user may wish to save this file with a different file name say test2.dat to retain a complete work record of the session. Addition of Bounds Tab on the Regression Form An additional tab showing the initial value and the lower and upper bound selected by WinProp for each regression variable specified has been added to the Regression form. The user may subsequently edit the bounds. The capability to restore values back to their default selections is provided as well. This provides the user greater flexibility in arriving at an EOS description based on the specific characteristics of the fluid being considered and the PVT data available. Volume Shift Specification Additional flexibility is introduced in selecting values for the volume shift parameter for each component. Previously the default was a value of zero for all components. The new default is a value generated from the correlation for library components and a value of zero for user defined components. The user may apply the correlation values to all components by selecting Reset to Correlation Values from the Volume Shift menu on the component form. Alternatively the user may revert to the older default by selecting Reset to Zeros. The user can still specify a value for any component which is different fromeither correlation or zero by editing the cell directly. Support of Two Sets of EOS Parameters WinProp now supports the concept of two different EOS models. When two sets are enabled the first set is used for calculations at reservoir conditions and the second set for surface or separator conditions. With this provision it is possible to match PVT experimental data at surface conditions (typically separator API and GOR data) independently fromdata at reservoir conditions. This makes it possible to obtain much more accurate predictions over the wide range of conditions encountered as the fluid is produced and processed on the surface with a realistic number of components for compositional simulation. Please refer to the Components and Regression chapters for details. Extended Separator Option The conventional separator operation involves the liquid phase output from a given separator becoming the feed for the next separator in sequence downstream and the vapor phase joining the gas product stream. This arrangement is not always optimal particularly for rich gas condensates. For modeling alternative separation strategies the separator option is enhanced to allow additional product streams such as LPG and in providing flexibility in the selection of the destination of the liquid and vapor stream from each separator. Please review the Laboratory Calculations chapter for more information about this feature. Multicomponent Solid Precipitation Model The solid precipitation model is now suitable for modeling both wax and asphaltene precipitation scenarios. The thermodynamic model has been enhanced as follows:the precipitate is now modeled as a multicomponent solid in contrast to the earlier single component pure solid phase assumption, non-isothermal conditions are treated, and up to three fluid phases in equilibrium with the solid are allowed. User Guide WinPropIntroduction 21 Introduction WinProp Overview WinProp is CMG's equation of state multiphase equilibrium property package featuring fluid characterization, lumping of components, matching of laboratory data through regression, simulation of multiple contact processes, phase diagram construction, solids precipitation, and more. Laboratory experiments considered in WinProp include recombination of separator oil and gas, compressibility measurements, constant composition expansion, differential liberation, separator test, constant volume depletion and swelling test. You can use WinProp to analyze the phase behavior of reservoir gas and oil systems, and to generate component properties for CMG's compositional simulator GEM, black oil simulator IMEX and steam and additives thermal simulator STARS. WinProp features a graphical user interface that allows you to prepare data, view plots of the input, run the phase property calculation engine, then view the text and graphical results within the program window.Use of this Manual This User Guide describes the different forms and options for entering data into WinProp. It is also available as on-line help. This User Guide is aimed at reservoir engineers with some background knowledge on the phase behavior and characterization of reservoir fluids. Good references on these topics can be found in Ahmed [1], Pedersen, Fredenslund, and Thomassen [30] and McCain [17] (see the References chapter). For more details on phase equilibrium thermodynamics, please see Sandler [35] or Walas [37]. Every attempt has been made in the preparation of this User Guide to provide you with all of the information necessary to run the program and understand the calculations being performed. If questions arise, please contact: Computer Modelling Group Ltd. 200, 1824 Crowchild Trail N.W. Calgary, CanadaT2M 3Y7 Telephone:(403) 531-1300 Fax:(403) 289-8502 Email:support@cmgl.caWebsite:www.cmgl.ca 22 IntroductionUser Guide WinProp Installation All CMG software must be installed from the CD-ROM by running the Setup program. Please refer to the detailed installation instructions that are packaged with the software for additional information. Confidentiality All components of CMG's technology including software and related documentation are protected by copyright, trademark and secrecy. CMG technology can be used only as permitted by your license from CMG. By the license, you have agreed to keep all CMG technology confidential and not disclose it to any third party. All rights reserved. No part of this publication may be reproduced or transmitted in any form or by any means, electronic, mechanical, or otherwise, including photocopying, recording, or by any information storage/retrieval system, to any party other than the licensee, without the written permission of Computer Modelling Group Ltd. Template Data Files A number of example data files are located in the "TPL" directory located under the WinProp directory. A brief description of each of the available template data files is shown below: Data file nameDescription AqueousCO2-08-Harvey.datAqueous phase properties calculation using Harveys method case_study-1.datData for case study number 1 (See Appendix A) case_study-2.datData for case study number 2 (See Appendix A) case_study-3-asph.datData for case study number 3 (See Appendix A) case_study-3-regress.datData for case study number 3 (See Appendix A) case_study-3-split.datData for case study number 3 (See Appendix A) cce.datConstant composition expansion calculation compgrad-blackoil.datCompositional gradient calculation - black oil compgrad-voloil.datCompositional gradient calculation - volatile oil compress.datSingle-phase liquid compressibility calculation cricon.datCricondenbar and cricondentherm calculation critical.datCritical point calculation cvd.datConstant volume depletion simulation diflib.datDifferential liberation experiment simulation envel_2ph-pt.datTwo-phase pressure-temperature envelope construction envel_2ph-px.datTwo-phase pressure-composition envelope construction envel_2ph-tern.datTwo-phase pseudo-ternary diagram construction envel_3ph-pt.datThree-phase pressure-temperature envelope construction envel_3ph-px.datThree-phase pressure-composition envelope construction extended_blackoil.datExtended black oil PVT tables with oil vaporization User Guide WinPropIntroduction 23 Data file nameDescription flash-2ph.datTwo-phase EOS flash calculation flash-3ph.datThree-phase EOS flash calculation flash-isenth1.datIsenthalpic flash - 2 component system flash-isenth2.datIsenthalpic flash - 6 component system flash-isenth3.datIsenthalpic flash - single component system flash-ogw.datThree-phase oil-gas-water Henry's law flash calculation format2_blackoil.datAlternate format black oil PVT tables imex_condensate.datIMEX gas-water with condensate PVT model data generation imex_voloil.datIMEX volatile oil PVT model data generation imex-blackoil.datIMEX PVT model data generation labpvt-bo1.datLab PVT experiment simulations black oil no. 1 labpvt-bo2.datLab PVT experiment simulations black oil no. 2 labpvt-bo3.datLab PVT experiment simulations black oil no. 3 labpvt-gc1.datLab PVT experiment simulations gas condensate no. 1 labpvt-gc2.datLab PVT experiment simulations gas condensate no. 2 labpvt-gc3.datLab PVT experiment simulations gas condensate no. 3 lumping.datLumping "plus fraction" components matbal-bo.datMaterial balance checks for black oil PVT experiments matbal-gc.datMaterial balance checks for condensate PVT experiments mcm-condensing.datCondensing gas drive multicontact miscibility calculation mcm-vaporizing-co2.datVaporizing CO2 drive multicontact miscibility calculation mcm-combined-H95-8lean.datCondensing and vaporizing combined drive MMP calculation mcm-combined-U2002rich.datCondensing and vaporizing combined drive MMP calculation mcm-Z12-5-MME.datCondensing and vaporizing combined drive MME calculation process-cvd.datProcess flow simulation of constant volume depletion test process-mcm.datProcess flow simulation of multiple contact experiment process-plant.datProcess flow simulation of a gas plant recombine.datRecombination of separator oil and gas streams regress-blackoil1.datBlack oil no. 1 regression regress-blackoil2.datBlack oil no. 2 regression regress-compress.datLiquid compressibility regression regress-condensate1.datGas condensate no. 1 regression regress-condensate2.datGas condensate no. 2 regression regress-critical.datCritical point regression regress-flash_2ph.datTwo-phase flash regression regress-flash_3ph.datThree-phase EOS flash regression regress-flash_ogw.datThree-phase Henry's law flash regression regress-lightoil.datLight oil regression regress-multicontact.datMultiple contact data regression regress-sat_pres.datSaturation pressure regression 24 IntroductionUser Guide WinProp Data file nameDescription regress-separator.datSeparator data matching with 2nd EOS set parameters regress-singlephase.datSingle phase properties regression regress-stream_frac.datAdjust gas and oil mixing ratio to match separator GOR regress-viscosity.datRegression for viscosity matching sat-pressure.datSaturation pressure calculation sat-temperature.datSaturation temperature calculation separator.datSeparator calculation singlephase.datSingle-phase fluid properties calculation solid-asph_plots.datPlot construction for single component asphaltene model solid-asph1.datSingle component solid asphaltene precipitation solid-asph2.datHeavy oil with 2 component solid precipitation solid-asph_temperature.datTemperature-dependent asphaltene modeling solid-phenanthrene.datPure component solid (phenanthrene) precipitation solid-wax.datMulticomponent wax precipitation split-mw_analysis.datCharacterization - MW versus mole fraction data split-mwsg_analysis.datCharacterization - MW, SG versus mole fraction data split-mwsg_plus.datCharacterization plus fraction MW and SG only split-mwsgtb_analysis.datCharacterization - MW, SG ,TB versus mole fraction data stars-comp_props.datComponent PVT properties generation for STARS stars-vl_kvalues.datVapor -Liquid K-values generation for STARS stars-vlaq_kvalues.datVapor -Liquid-aqueous K-values generation for STARS stars-vls_kvalues.datVapor -Liquid-solid K-values generation for STARS stdrm017props.datCreate fluid model for STARS stdrm017 template stflu008props.datCreate fluid model for STARS stflu008 template sttst26props.datCreate fluid model for STARS sttst026 template swelling.datSwelling experiment simulation User Guide WinPropBasic Operations 25 Basic Operations Overview This chapter provides basic information for creating, editing, saving and running data sets in WinProp, as well as for viewin