Virtual Materials Group Inc.


Thermodynamics and Physical Property Software Component

VMGSim offers accurate, robust and cost effective process simulation solutions to predict the detailed behaviour of process units and plants. Whether designing new process units, optimizing, revamping or troubleshooting, VMGSim assists engineers to improve operating efficiency and product quality, reduce capital and operating costs, and provide greater safety and increased profitability. VMGSim is your reliable partner in modeling entire process units in the Oil & Gas, Refining, Chemical and Petrochemical industries. Important industrial processes such as natural gas sweetening using amines and physical solvents, Claus plants and tail gas treatment can be easily and seamlessly simulated without special workarounds or awkward combination of unit operations.

VMGSim uses the extremely popular interactive calculation principles of non-sequential, unit operation calculations with partial data flow developed in the late 1970’s by Craig Morris. These concepts combined with VMGSim’s state of the art graphical user interface provide you with the fastest, most intuitive way for the development and evaluation of process models. VMGSim is your true partner, helping you set up your simulation and performing complex information checking in the background. Information is propagated through the flowsheet instantly and calculations performed whenever possible. VMGSim behaves like you do, making the most of whatever information you have available while using the rigorous boundaries provided by chemical engineering science and thermodynamics. After using VMGSim for a few days you will ask yourself why you are so productive so fast and why other programs try to make you think their way instead of the other way around.

You will notice VMG’s uncompromising commitment to quality the moment you start using VMGSim. Forms are carefully designed with the expert and novice in mind. Specialized unit operations allow you to quickly build complex flowsheets that closely resemble your plant. Incredible complexity related to the solution and convergence of complex flowsheets is handled elegantly and consistently by VMGSim. Last but not least, VMGSim is built on the bedrock provided by VMGThermo and more than a decade of development and validation of thermodynamic models used from on-line monitoring applications to dynamic simulation to heat exchanger design. Form and function are artfully blended with chemical engineering science and technology to deliver a tool of exceptional quality to you. Our goal is to free your imagination and allow you to be as productive as possible, today, tomorrow and beyond.

VMGSim – State of the art steady state and dynamic simulation brought to you by Virtual Materials Group, Inc.

Thermo-physical Properties – Our Core Strength

At VMG we understand that simulations are only as good as the underlining thermodynamic model. We work on thermodynamics, physical properties and flash calculations every day. We develop and implement our models, determine our own interaction parameters and work with the best providers of physical property data to ensure you have the very best models validated using the best possible data. Decades of experience, research and development in applied thermodynamics are captured in VMGThermoTM. VMGThermoTM is an extremely comprehensive property package engine which includes support for chemically reactive systems, oil and rigorous multiphase flash, combined with extensive selection of equations of state and activity coefficient models.

VMGThermo includes a comprehensive pure component database with more than 20,000 pure components developed based on evaluated data from the National Institute of Standards and Technology Thermodynamics Research Center. VMGThermo is engine under VMGSim’s hood. It is also widely used as a plug-in engine by many well-known third-party on-line and off-line applications such as HTRI’s Xchanger Suite, NEOTEC’s pipeline simulation products, Ariel Corporations Compressor, Farris’s iPrism, Berwanger’s PPM and IDEAS’s Operator Training and Dynamic Simulation. This ensures that our thermodynamic calculations are put under extraordinary stress and provide quality results for conditions and expectations well beyond process simulation.

Comprehensive coverage for different industries and several modeling options to support your modeling task – this is the power of VMGThermo.

Accurate Documented Thermo-physical Properties

  • Carefully validated property packages for natural gas, refining, chemical and special processes such as amine sweetening, sulphur treating plants and power cycles.

VMG develops and validates its own thermodynamic models. We can always tell you how the model was developed and what are the underlining assumptions, weaknesses and strengths. Our partnership with NIST/TRC gives us unparallel capabilities to verify our models against experimental data.

  • Accurate CO2 freezing point, Hydrate calculations including inhibition using ethylene glycol and methanol.
  • Comprehensive Claus Property package

Unusual physical properties? No problem, even when polymerization in liquid phase happens.

  • Comprehensive Amines Property package

Unusual physical properties? No problem, even when polymerization in liquid phase happens.

  • Comprehensive Pure Component Library – 20,000+ pure components
  • Extensive collection of Equations of State and Activity models with consistent interaction parameters.
  • Built-in pure component and mixture parameter estimation
  • Visual structure builder for pure components

Build molecular structures by dragging and dropping atomic fragments. VMGSim will estimate the necessary physical properties using group contribution methods whenever possible.

  • Extensive mixture interaction parameter database with data source references
  • Refinery Oil assay characterization and blending
  • Unparallel coverage of physical properties - speed of sound, actual Cv, isothermal compressibility amongst many others

VMGSim has a complete set of physical properties that go well beyond what you would find in a common process simulator. For example, estimates for speed of sound – in vapour or liquid phase – are available by default.

VMGSim offers a comprehensive suite of critically evaluated data for over 20,000 pure components and a mixture interaction parameter database of over 100,000 binary parameters – evaluated in-house and carefully tuned to our flash engine and pure component properties.

VMGSim uses comprehensive interaction parameter databases determined by VMG. No inconsistencies from using a motley selection of models and pure component data.VMGSim can not only predict complex thermodynamic behaviour such as double azeotropes, it but it can also tell you exactly what the model parameters are and the origin of thermodynamic data.

Advanced Crude Oil Characterization

VMGSim features a powerful, easy-to-use and accurate package for the characterization of crude oils. A comprehensive selection of distillation curve inter-conversion methods in volume, mass or mole are provided including TBP, D86, D1160, D1160 Vacuum, D2887 and an option to create a curve from simply bulk properties. A wide range of additional data such as Density Curves,

Molecular Weight Curves, and Viscosity Curves can be included in the assay description. Light-ends may be input with the assay or back-calculated from assay data. Also there is the unique ability to match the bulk oil density, viscosity and thermal conductivity as a function of temperature. Multiple assays and multiple blends can be defined, managed and utilized in a simulation case. Changes to assays or blends are automatically reflected in the simulation model, including automatic recycle convergence.

VMGSim’s state of the art oil characterization interface is the most modern in the business. Add assays and blends, specify ranges and physical property estimation methods easily and consistently.

Unit Operations

VMGSim is a general process simulator and possesses a complete suite of process unit operations which can be configured to model virtually any process of interest in the Gas processing, Refining/Petrochemical or Chemical industries.

Unit Operations Library

  • Distillation - rigorous, robust and fast two and three phase distillation including complex refinery configurations and heterogeneous azeotropic distillation.

VMGSim features an incredibly flexible distillation simulation algorithm coupled with an easy to use graphical interface and configurable reporting capabilities. The distillation simulation algorithm works closely with our property package system and special convergence algorithms and tray efficiency calculation are used without complex settings. You concentrate on the modeling we concentrate on the mathematics.

  • Two- and Three-phase separators with multiple feeds and energy input
  • Mixers, Tees, Component  Splitters
  • Balances - Mole, Mass and Energy balance operations
  • Excel™ Embedded unit operations with fully featured spreadsheet, macros and Visual Basic for Applications

VMGSim is seamlessly integrated with Microsoft Excel. Data from VMGSim and other applications – such as a DCS system – can be brought into Excel and complex calculations performed using macros or Visual Basic for Application. You don’t have to worry about the communication details and spend your time on developing your solution.

  • Pumps, compressors, expanders with option to input performance curves
  • Control valves and relief valves
  • Multiphase pipe operation
  • Shell and Tube and Air Cooler rating

Heat exchanger rating is one of VMGSim’s most comprehensive functions. Flexible configuration options allow accurate hardware modeling and matching to plant data. Sensitivity trending is available using built-in case studies to further help understand plant operations.

  • Shell and Tube exchanger operation with rating using HTRI or STX
  • Multi-stream heat exchangers

A typical TEAL liquefaction process -Feed gas is cooled, the heavier components recovered, nitrogen is stripped then further cooling is completed to create the LNG product.

  • CSTR, Plug-Flow, Equilibrium, Gibbs and Stoichiometric Reactor models
  • Flowsheet Controllers and Sets
  • Liquid-Liquid extractor
  • Gas orifice
  • Ejector

Sulphur Plant Operations

VMGSim’s Claus Unit operations: Reaction furnace, Waste Heat Boiler, Claus Converter, Indirect Reheater, Direct Fired Reheater, Claus Oxygen Calculator, Sulfur Condenser, Hydrogenation Reactor, Reducing Gas Generator, Selective Oxidation Reactor and Sulfur Pit. Configured to ensure easiness of use and convenience for process engineers.

  • Waste Heat Boiler
  • Catalytic Converter
  • Reheat Burner
  • Hydrogenation Reactor
  • Oxidation Reactor
  • Sulphur Condenser
  • Incinerator
  • Sx Properties
  • Air/O2 Ratio Calculator

Special Utility Operations

  • Phase Envelope – Temperature/Pressure (TP), Pressure/Enthalpy (PH), Pressure/Entropy (PS), Temperature/Enthalpy (TH) diagrams including calculation of critical point, hydrate curve and quality lines

Process Simulation Models closelyrepresent the true behaviour of manufacturing processes and additional insight can be gained by exploring the thermodynamic space using phase envelopes, XY diagrams and property tables.

  • Saturator - saturate a gas stream with water or any other component
  • Hydrate - calculate the hydrate temperature and pressure for two, three and four phase hydrates including inhibitors such as methanol and ethylene glycol
  • Special Properties for Natural Gas – calculate useful  properties such as heating values, dew point, water dew point, Wobbe index, enthalpies of vaporization and pseudo-critical properties.
  • Special Properties for Refining – Reid Vapour Pressure (RVP), flash point, pour point, viscosity, Research Octane Number (RON), Motor Octane Number (MON), refractive index
  • Property Table - generate plots and tables of physical properties for mixtures using configurable ranges.

A complete set of physical properties important for different industries is available through the Special Properties unit operation. As with most of the information in VMGSim it can be integrated directly into ExcelTM for reporting or development of special functions.

  • Distillation  Curve  - generate boiling temperature assays for a given composition
  • XY Curve - generate XY diagrams for a given stream and key component at any pressure or temperature
  • Gibbs Curve  - generate Gibbs free energy of mixing curve for a given stream and key component at a pressure and temperature
  • Oxygen Calculator - determine excess O2 for a given reaction
  • Sulphur Detail – track key parameters in you Sulphur plant Sx, Dewpoint, H2S/SO2, etc.
  • Amine Detail - track key parameters in you amine model in the way you work and use them for setting flowsheet parameters such as rich to lean carbon dioxide and hydrogen sulphide loading

The Amine Detail provides a comprehensive summary of the key amine stream performance values like acid gas molar loading ratio and the amine weight percent. These values are also available for use in the flow sheet. Control the flow rate of lean amine to meet a desired rich amine loading or feed duty to feed ratio specifications.

  • Material Balance – Easily  generate an overall material and energy balance for the entire flowsheet
  • Psychometric Chart– determine or set humidity and relative humidity for a stream
  • Embedded Equipment Rating and Design Third Party Applications  such as HTRI’s XChange Suite

Rigorous tray by tray complex column

VMG features a very fast and robust column algorithm carefully tuned to reliably converge on difficult complex refining distillation columns or reactive systems encountered in amine sweetening. The tower supports two and three phase distillation and conveniently handles Side Strippers, Pump Arounds, Heaters, Coolers and multiple product and water draws. The tower has a full range of specifications and trays can be designed or rated.

Acid Gas Treating

VMGSim features a comprehensive system for modeling the removal of H2S and CO2 from process streams. The system includes an extensive slate of chemical and physical solvents, an advanced tower model that incorporates mass transfer effects along with a carefully validated electrolyte model that accurately predicts chemical and physical equilibrium. The following solvents are supported: Amines (MEA, DEA, MDEA, TEA, DIPA, AMP, DGA, Mixes); Physical Solvents (SELEXOL, Propylene Carbonate, NFM, NMP). Any number of mixed solvents and/or amines is supported.

Developed entirely in-house through an exhaustive analysis of literature data and models, VMG’s amines and physical solvents packages embody the results of years of painstakingly detailed modeling efforts. A fully reactive flash is supported throughout the flow sheet. A flexible formulation for the liquid phase free energy allows rigorous modeling of ion-ion, ion-solvent and solvent-solvent interactions.

Claus and Tail-gas Treating

VMGSim provides a complete set of unit operations and a specialized property model for designers and plant operators to design, optimize, monitor and troubleshoot Sulphur Plants. These features are incorporated into the modern, user-friendly comprehensive core of VMGSim so that Sulphur plants can be modeled in a fully integrated flowsheet with acid gas treating units and general processing such as an entire refinery model. VMG has also taken great care in capturing the best available data in the world to produce an accurate and validated property package and unit operations.

VMG’s Claus property package is carefully integrated with VMGSim providing you with a specialized, self-contained and easy to understand interface to unit operation models. Instead of cobbling together several unit operations or having to endure inflexible flow sheet configurations, VMGSim provides you with the best selection of unit operations specially designed to model Claus type processes.

VMGSim Dynamics

Rigorous dynamic simulation is now available as an option in VMGSim. The dynamic models share the same thermodynamics engine as steady state, but use a dynamic network pressure-flow solver. This permits calculation of flowrates and pressures as a function of system parameters such as valve Cv, rather than using fixed, user-specified values.

three-stage gas compression on an offshore platform. The model was built to evaluate the performance of the existing pressure/speed control scheme for the compressor, and to attempt to find an alternate scheme which would lead to less variability and less flaring.

VMGSim COM Engine

At VMG we know you may want to use models in ways we have never dreamed before. You can tap into VMGSim’s programmable interface and drive simulations using COM compliant tools such as Excel, Visual Basic, C# and C++.

Using VMGSim as a plug-in simulation engine you can go the distance:

  • Develop your own user interfaces
  • Run embedded models for plant monitoring or optimization
  • Integrate custom calculations originally developed in Excel™ or other programming languages
  • Interface to databases and word processing programs

Leverage your existing knowledge in the use of Excel for the development of interfaces or custom calculations. Use thousands of COM compliant software components for the development of custom engineering databases, optimization, data mining and reporting.

Embedded Applications, Customization, Real-time Applications

Excel™ – VMG has the most advanced integration with ExcelTM in the business. First released in 2003 VMGSim offers Excel as an embedded unit operation in the flowsheet. Embedded ExcelTM spreadsheets are fast and seamless, running interactively with other unit operations in the model. ExcelTM workbooks can simply be added to the flowsheet as quickly and easily as a standard unit operation. The workbooks can freely exchange data within the model and can obtain data directly from DCS systems, data historians or other programs.

Excel™, Macros and Visual Basic for Applications (VBA) can also be used to create custom applications utilizing VMGSim’s COM Interface. Applications of this nature are able to bypass the use of the VMGSim GUI which allows for increased speed and configuration flexibility which is particularly useful for automation applications. Applications can be written using any COM compliant language available in the Microsoft Windows platform.

Real-time monitoring and optimization tools

VMGSim’s modern programming architecture and component structure makes it one of the easiest modeling systems to integrate with real time applications. We currently have advisory VMGSim models for plant supervisory applications and for profitability modeling running on-line in a variety of facilities including refineries and gas plants.

DCS interface - 3 different link configurations have been implemented successfully between VMGSim and a distributed control system (DCS). This is possible due to the object oriented structure of the

VMGSim software, solver holding/triggering capabilities, and the available VSimCom COM interface to VMGSim. The first option involves a direct connection between VSimCom and the DCS if an object linking and embedding (OLE) or COM interface is available within the DCS. The second option uses the ExcelTM operation within VMGSim and the Excel add-in capabilities of a DCS if applicable. The last option has been to read/write VMGSim values from a OLE or COM compliant database, which is then accessed by the DCS as means of an indirect link.

Supported databases - VMGSim’s modern architecture enables it to talk to just about any program imaginable, including databases of all types. Our users have developed a wide range of applications that read/write to databases such as Microsoft Access™ with relative ease. The modern architecture of VMGSim puts it at the top of the industry in terms of integration with other software applications.

Embedded Excel Unit Operations

Excel Unit Operations provide you with the convenience of using a professional spreadsheet directly inside VMGSim. No programming is required; you simply drag the Excel icon from the unit operation palette to add Excel workbooks to the model. Select import/export to attach information from a stream or another unit operation to the worksheet. The Excel operations will behave exactly like any other unit operation, triggering flowsheet calculations or reacting to changes in the flowsheet exactly like a native VMGSim unit operation. Information is automatically recalculated and propagated without the need of cumbersome programming or specialized interfaces. There are no limits to the number of ExcelTM worksheets you can have in a model.

VMGSim pioneered Excel direct embedding into a process simulator at the unit operation level. This functionality allows you access to all high level functions from VMGSim in a familiar environment and perform tasks of any level of complexity, from simple cell operations to complex procedures using Visual Basic for Applications. Models can be tailored for specific applications and end-users whether they are engineers, managers or operators.

In addition, since you are working directly inside Microsoft Excel you have full access to Visual Basic for Applications (VBA) without the need of writing a single line of automation code. If you are used to program spreadsheets using complex cell formulas and macros you can be immediately productive using ExcelTM unit operations in VMGSim. Develop your own unit operation model such as a specialized reactor and integrate external data easily and consistently.

VMGSim Advanced Reporting Features

The new, fully integrated reporting system in VMGSim makes it easy for you to extract the most relevant information from your simulation and incorporate it into professional quality reports. Project Report automatically generates a detailed, fully customizable report template of your simulation. The project report is fully customizable from a simple to use, single form. The novel Summary Sets make for easy selection, collection and display the most relevant information from your simulation in tabular format.

With VMGSim’s Report functionality you can easily navigate through complex simulations and access important data in the same way you would use a Web browser using hyperlinks.

Full Windows Productivity

The Excel™ operation may be added to the flowsheet and utilized for custom reporting. A click of the mouse with paste the connections of the model data into the spreadsheet in your personal format and these connections will be updated in the spreadsheet automatically from the model when changes to the model are made. ExcelTM provides limitless formatting and multiple workbooks to allow custom reports to be permanently built into your VMGSim cases and always kept up to date and in the exact format your prefer.

All numeric data and tables in VMGSim are copy and paste enabled for information transfer to other Windows programs.

VMGSim and Microsoft Excel™ are seamlessly integrated into a powerful simulation environment. Take advantage of all the experience you have with Excel and put it to work immediately with VMGSim, either by formatting data and plots, writing macros or complex algorithms using Visual Basic for Applications.

Equipment Sizing and Rating

VMGSim has a number of sizing and rating calculation tools including:

  • Vessel Sizing/Rating – Size two and three phase separators

Quickly size important process equipment such as vapour-liquid separators. Multiple case studies are available to allow for fast and efficient comparison and ranking of different solutions.

  • Tray Sizing/Rating – Size or rate distillation trays with a number of methods and multiple designs per vessel.
  • Relief Valve – Calculate the orifice area for a single or two phase relief valve given a set of inlet conditions.
  • Gas Orifice Meter – Calculate orifice differential pressure value when given the pipe diameter, orifice diameter, gas flow rate and inlet process conditions, or alternatively calculate the flow rate when an orifice differential pressure is provided.

VMGSim Automation Links to Xchanger Suite™ and HTC STX/ACX™

Virtual Materials Group’s has a comprehensive set of interfaces and automation links to Xchanger Suite™ and STX/AXC™.

VMGSim users can perform heat exchanger rating and design calculations directly from a VMGSim simulation model without manually transferring data or leaving the simulation model. In addition users can click a button to embed rigorous exchanger simulations into a VMGSim case enabling rigorous prediction of exchanger output conditions and pressure drops in VMGSim models.

From any heat exchanger operation in the VMGSim simulation model, users can access HTRI or STX’s rigorous exchanger design, rating and simulation capabilities. Clicking the live link button will automatically connect the process model to the heat exchanger design program and the required information, including physical properties and stream inlet and outlet conditions are propagated. At any time, users may view and work in the heat exchanger program interface and the VMGSim interface. In addition to the rating, design and simulation the live links feature provides the option to create a separate input file for Xchanger Suite, STX/ACX and HTFS TASC

VMGSim includes live link interfaces within heat exchangers and air coolers to popular design and rating software such as HTRI’s Xchanger Suite and HTC’s STX and ACX. These links allow imbedded use of these established and proven design tools directly within VMGSim flowsheets.





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