Plant Model - Species and Environment
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Navigation: View Commands -> Plant Model -> Plant Model - Species and Environment
This page is valid for SysCAD 9.2 and later builds.
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Contents |
Species tab page
| Tag / Symbol | Input / Calc / Options | Description/Calculated Variables |
Calculation Methods | ||
| Fidelity | High | The model uses the high fidelity equations to determine steam and water energy. See High fidelity in Standard Species Model |
| Low | The model uses low fidelity equations to perform water and steam calculations. See Low Fidelity in Standard Species Model | |
| H2OProperties | Feedback | This displays the Steam/Water calculation method. The default if IF97H2O, which uses the industrial standard IAPWS-IF97. |
| TreatWaterAsAq | Feedback | This displays whether the Recognise H2O(l) As Aqueous option has been selected in the Project's Configuration File or not. The default for this is Yes. |
| Enthalpy Strategy | Best_Temperature | The method used for energy balance when mixing streams with different properties models that may have different stream enthalpy calculations. Attempt to maintain temperature, adjust enthalpy. Use the outgoing properties enthalpy model when mixing streams. Note that in this case, the enthalpy of the outgoing stream may not be equal to the sum of the incoming stream enthalpies. When mixing two streams of the same temperature, the outgoing temperature will be equal to incoming temperature provided there is no concentration dependence of the enthalpy function. |
| Conserve_Heat | The method used for energy balance when mixing streams with different properties models that may have different stream enthalpy calculations. Maintain enthalpy, adjust temperature. In this case the enthalpy of the outgoing stream is guaranteed to equal to the sum of the incoming stream enthalpies. | |
| SaturationCmp | H2O | By default the saturation component used in any VLE blocks will be H2O. The user can override this in the individual VLE block. |
| All - H2O | The saturation component used in all VLE blocks will be H2O, the user cannot override this in the individual VLE block. | |
| component X | By default the saturation component used in any VLE blocks will be component X (any component which is available for VLE). The user can override this in the individual VLE block. | |
| All - component X | The saturation component used in all VLE blocks will be component X (any component which is available for VLE), the user cannot override this in the individual VLE block. | |
Auto Phase Change Equilibrium | ||
| Solubility | Off | Solubility does not occur automatically in the project. This will be the default (and greyed out) if there are no solubility functions in the species database. |
| On | Solubility will occur automatically throughout the project for all species with solubility functions in the species database. Please see Phase Change in Species Database for further details. (An example of this is the dissolution or precipitation of NaCl in solution according to the temperature.) | |
| PhaseChange@T | Off | Phase change at Temperature will NOT occur automatically. This will be the default (and greyed out) if there is no function defined in the species database. |
| On | Phase change at Temperature will occur automatically throughout the project for all species with defined Phase change at Temperature functions in the specie database. Please see Phase Change in Species Database for further details. (An example of this is Hematite (Fe2O3(s)) changing automatically from the alpha to the beta form at 427oC.) | |
| PhaseChange@MF | Off | Phase change at Mass Fraction will NOT occur automatically. This will be the default (and greyed out) if there is no function defined in the species database. |
| On | Phase change at Mass Fraction will occur automatically throughout the project for all species with defined Phase change at Mass Fraction functions in the specie database. Please see Phase Change in Species Database for further details. (An example of this is H2SO4 changing automatically from the liquid to the aqueous phase at 98.3% acid) | |
| AutoVLE | Off | Automatic vapour-liquid equilibrium (VLE) will NOT occur automatically. This is the default setting for all upgraded and new projects. |
| On | Automatic vapour-liquid equilibrium (VLE) will be enabled in all pipes. The calculations will use the default Saturation species for the calculations. See Vapour Liquid Equilibrium (VLE) for further details. | |
Standard Properties Model Options | ||
| DensityCorrection | SysCAD 9.1 | The method used in SysCAD 9.1 and earlier. This will only be displayed for projects were upgraded from an earlier version of SysCAD and contained density correction. Once the density correction method is changed to one of the other 2 methods (highly recommended) this option will no longer be visible. |
| FracInSolventOnly | The density correction calculations use the mass fraction of individual species in the solvent ONLY. The resulting density correction factor is greater than the value calculated using the method below. Please see Density Correction Methods for a more detailed description. | |
| FracInAqueousSoln | The density correction calculations use the mass fraction of the individual species in the TOTAL aqueous solution. The resulting density correction factor is smaller than the value calculated using the method above. Please see Density Correction Methods for a more detailed description. Note: This method is only valid if the solvent is Water. | |
| BPE_Method | None | No Boiling Point Elevation (BPE) calculations will be performed, i.e. BPE = 0°C in all streams with the Standard Species Model. |
| VantHoff | The BPE will be calculated using the equation shown in Boiling Point Elevation and the van't Hoff constants as entered in the Species Database. | |
| BPE Lo Limit | Input | The lower limit for the BPE calculations - usually 0°C. |
| BPE Hi Limit | Input | The upper limit for the BPE calculations - the default is 20°C, but if the project has concentrated solutions the upper limit may need to be higher. |
Species Count | ||
| SpecieCount | Display | The total number of species in the project. |
| SpecieSolCount | Display | The number of solid species in the project. |
| SpecieLiqCount | Display | The number of liquid species in the project. |
| SpecieVapCount | Display | The number of vapour or gas species in the project. |
Lockup Species SelectionPlease see LockUp for further information. | ||
| Set | None | No species in the project will have Lockup enabled. The user may NOT set lockup in any Feeders or Pipes. |
| Phase | The user may select a phase and then any species within the selected phase(s) may have Lockup enabled. | |
| Individual Phase | The user may select an Individual Phase and then any species within the selected Individual Phase(s) may have Lockup enabled. | |
| Species List | The user may select individual species that may have Lockup enabled in Feeders or Pipes in the project. | |
| Solids | Tickbox | Only visible if Phase is selected. If the user enables this, then any solid species may be selected to have Lockup in a Feeder or Pipe. |
| Liquids | Tickbox | Only visible if Phase is selected. If the user enables this, then any Liquid species may be selected to have Lockup in a Feeder or Pipe. |
| Gasses | Tickbox | Only visible if Phase is selected. If the user enables this, then any gaseous species may be selected to have Lockup in a Feeder or Pipe. |
| Speciexx | List of Species | Only visible if Species List is selected. The user may select the individual species that may have lockup enabled in the project. Any number of species may be selected. |
Additional Properties Options | ||
| PropertyOptions... | ||
| Energy | Tickbox | If this is enabled then Energy Flow Properties will be added to the project (except for the Values at User defined Temperature and Pressure). These will be visible for all streams. Otherwise they will be removed from the project (except for the Values at User defined Temperature and Pressure). |
| Saturation | Tickbox | If this is enabled then Saturation variables will be added to the project. These will be visible for all streams. Otherwise they will be removed from the project. |
| pH_Estimate | Tickbox | If this is enabled then Acidity (pH) variables will be added to the project. These will be visible for all streams. Otherwise these variables will be removed from the project. |
| Transport | Tickbox | If this is enabled then Transport Properties (including viscosity) will be added to the project. These will be visible for all streams. Otherwise they will be removed from the project. |
| DensityCorrections | Tickbox | If this is enabled then additional Density Correction variables will be added to the project. These will be visible for all streams. Otherwise these variables will be removed from the project. |
| ValuesAtUserTandP | Tickbox | If this is enabled then Values at user defined temperature and pressure will be added to the project. These will be visible for all streams. Otherwise they will be removed from the project. |
| User DefT | Input | The user defined temperature. |
| User DefP | Input | The user defined pressure. If this is left as a * then the saturation pressure will be used. |
Material View Options | ||
| SpecieViewOptions... | ||
| Species Conc | Tickbox | If this is enabled then all variables displaying the Species concentration will be added to the project and will be visible on all the streams. If it is disabled then these variables will be removed from the project. |
| Species Molar | Tickbox | If this is enabled then all variables displaying the species Molar flow / fraction will be added to the project and will be visible on all the streams. If it is disabled then these variables will be removed from the project. |
| Species Volume | Tickbox | If this is enabled then all variables displaying the species Volume flow / fraction will be added to the project and will be visible on all the streams. If it is disabled then these variables will be removed from the project. |
| Species Norm Volume | Tickbox | If this is enabled then all variables displaying the species Normal Volume flow / fraction will be added to the project and will be visible on all the streams. If it is disabled then these variables will be removed from the project. |
| Species PartialP | Tickbox | If this is enabled then all variables displaying the species Partial Pressure will be added to the project and will be visible on all the streams. If it is disabled then these variables will be removed from the project. |
| Species Enthalpy | Tickbox | If this is enabled then all variables displaying the species Enthalpy will be added to the project and will be visible on all the streams. If it is disabled then these variables will be removed from the project. |
| Component Mass | Tickbox | If this is enabled then all variables displaying the Component Mass flow / fraction / concentration will be added to the project and will be visible on all the streams. If it is disabled then these variables will be removed from the project. |
| Component Molar | Tickbox | If this is enabled then all variables displaying the Component Molar flow / fraction / concentration will be added to the project and will be visible on all the streams. If it is disabled then these variables will be removed from the project. |
| Element Mass | Tickbox | If this is enabled then all variables displaying the Elemental Mass flow / fraction / concentration will be added to the project and will be visible on all the streams. If it is disabled then these variables will be removed from the project. |
| Element Molar | Tickbox | If this is enabled then all variables displaying the Elemental Molar flow / fraction / concentration will be added to the project and will be visible on all the streams. If it is disabled then these variables will be removed from the project. |
Environment tab page
Project Configuration Temperature and Pressure(NOTE: The temperature and pressure values can only be changed via the Edit Configuration command prior to loading of project, except for the standard temperature and pressure which has been hardwired.) | ||
| NormT | Feedback | Normal temperature specified in the configuration file. |
| NormP | Feedback | NormalpPressure specified in the configuration file. |
| StdT | Feedback | Standard temperature, hard wired to 25 deg C. |
| StdP | Feedback | Standard pressure, hard wired to 101.325 kPa. |
| PrjMinP | Feedback | Minimum project pressure specified in the configuration file. |
| PrjMaxP | Feedback | Maximum project pressure specified in the configuration file. |
| PrjMinT | Feedback | Minimum project temperature specified in the configuration file. |
| PrjMaxT | Feedback | Maximum project temperature specified in the configuration file. |
Environment | ||
| Elevation | Input | Elevation above sea level, used to calculate the atmospheric pressure. |
| AmbientTemp / T | Input | The Ambient Temperature. The ambient temperature is used by some models, eg Environmental Heat Exchanger - loss to Ambient |
| AirPressure / P | Calc | The atmospheric pressure calculated by the elevation. |
| AirDensity | Calc | The Density of Air at the specified elevation. Reference for Air Pressure and Air Density calculation: Perry's Chemical Engineers Handbook, 7th Edition, TABLE 2-236 Thermodynamic Properties of the International Standard Atmosphere. |
| WindSpeed | Input | The average wind speed |
| WindDirection | Input | The wind direction. |
| RelativeHumidity | Input | The relative humidity of air. 100% humidity = fully saturated. 0% = no water in air. |
| Environment.Air... | ||
| State | Feedback | Feedback information to show if gaseous components are present in the project. |
| species 1 | Input | If a gaseous species is present in the project, it will be available here to define the environmental air composition on a mass basis. |
