TERMOINT SOFTWARE PACKAGE: PHYSICAL PROPERTIES OF PURE COMPOUNDS AND MIXTURES

DIEGO NUÑEZ; MARCELO S. ZABALOY

Buenos Aires, Argentina

Congreso; XXII Congreso Interamericano de Ingeniería Química y V Congreso Argentino de Ingeniería Química; 2006

TERMOINT is a software package under development at the Group of Process Thermodynamics of PLAPIQUI. TERMOINT is, on one hand, a friendly interface that makes possible to access a large physical properties database [1]. This database provides constant and temperature-dependent physical properties for hundreds of pure compounds. Property values are available for, for instance, liquid and vapor density, vapor pressure, critical constants and vaporization enthalpy. Using TERMOINT, it is possible to perform several tasks on the DIPPR database: (a) Generation of 2D plots where, for a user-defined set of pure components, a given constant, e.g., the critical temperature, is plotted as a function of another constant, e.g., the molecular weight. (b) Plotting a given property, e.g., the saturated liquid density, as a function of temperature. (c) Computing the value of a property, such as the vaporization enthalpy, at a temperature value set by the user. (d) Generating tables of values of physical constants for a user-defined set of pure compounds (e) Changing the limits and the scale nature for the generated plots. It is also possible to search for pure compounds matching user-defined restrictions set on different constant properties. TERMOINT query and plot results can be exported to EXCEL. On the other hand, TERMOINT links the DIPPR database to thermodynamic models for the calculation of fluid phase equilibria. For the time being, TERMOINT makes possible to fit parameters for the Group Contribution Equation of State (GC-EOS) [2]. This is a thermodynamic model applicable over a wide range of conditions, which exploits the group contribution concept. In the group contribution approach it is assumed that the effect of attractive intermolecular forces is a function of the properties of the functional groups that constitute the molecules present in the system, regardless of the location of the groups within a given molecule. The programming language used for implementing TERMOINT is Visual Basic. TERMOINT has proven to be a very practical tool for studying engineering problems dominated by the physical properties of the materials involved. The development plan for TERMOINT foresees the incorporation in the near future of a number of GC-EOS programs for calculations such as multiphase flash separations, mixture bubble and dew points and multicomponent phase envelopes.