Material Content Section - pH, Charge and Transport Properties

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Navigation: Models ➔ Common Sections ➔ Material Content Section ➔ Acidity (pH), Charge, Transport

Material (Content) Content Tab Include Properties Species (Sp) Optional Tabs
Basic Information Energy
ValuesAtUserTandP
Density Correction
Solubility
Saturation
Acidity
Charge
Transport
HeatsOfCombustion
Heating Values
Solution Impurity
H2O Properties
Water Quality Sp Tab
EC Tab
DLockup
LockUp
DTrack
Track
DSz
Sz
MSz
DSSA
SSA

Related Links: Common Content Section


This section is used to display the included properties for: Acidity, Charge and Transport.

Data Section

Tag (Long/Short) Input / Calc Description/Calculated Variables / Options

Acidity (pH)

These values are calculated based on the Ka and Kb values for acids and bases that are defined in the species database. It does not take buffering into account, and hence is, at best, an estimate of the pH.

SysCAD does have default Ka and Kb values defined for some acids and bases, and the user may enter values for other compounds. For a description of the method that SysCAD uses to calculate the acidity values see Acidity Calculations.

These values will only be shown if the user has chosen to display the pH_Estimate variables on the Plant Model - Views tab page or from the Include Properties dropdown list on the first page of the material Content section.

Acidity(@25C)
pH.State Calc Either OK - only acids or bases present, OR Acid and Base present, therefore the calculations will be inaccurate.
pH.negLogH Calc This is the negative of the log of the Hydrogen ion molar concentration at 25°C.
pH.AcidsPresent List This lists all of the acids present in the content that are used to calculate [H+] (molar concentration).
pH.BasesPresent List This lists all of the bases present in the content that are used to calculate [OH-] (molar concentration).
pH.H_Cation Calc Only displayed if the species list includes H+(aq). This is the negative of the log of the Hydrogen ion molar concentration at 25 °C, due only to the presence of the H+(aq) ion (all other acids and bases are ignored).

Charge

These values are calculated based on the species charges that are defined in the species database.

These values will only be shown if the user has chosen to display the Charge variables on the Plant Model - Views tab page or from the Include Properties dropdown list on the first page of the material Content section.

Charge.State Calc Either Neutral (charge is balanced), Positive (positively charged) or Negative (negatively charged).
Charge.Overall Calc The overall charge of the material in the content.
Charge.CationsPresent List This lists all of the positively charged species present in the content that contribute to the overall charge.
Charge.AnionsPresent List This lists all of the negatively charged species present in the content that contribute to the overall charge.

Transport Properties

These properties are related to the transport properties of the stream, e.g. viscosity, etc. These will only be shown if the user has chosen to display the Transport Properties on the Plant Model - Views tab page or from the Include Properties dropdown list on the first page of the material Content section.

VViscosity Calc (Dynamic) Viscosity of the vapour phase
LViscosity Calc (Dynamic) Viscosity of the liquid phase
VKinematicVisc Calc Kinematic Viscosity of the vapour phase = Dynamic Viscosity of vapour phase (VViscosity) / Density of vapour phase (VRho)
LKinematicVisc Calc Kinematic Viscosity of the liquid phase = Dynamic Viscosity of liquid phase (LViscosity) / Density of liquid phase (LRho)
VThermalCond Calc Thermal Conductivity of the vapour phase
LThermalCond Calc Thermal Conductivity of the liquid phase
VPrandtlNo Calc Prandtl’s number for the vapour phase = heat capacity (VmsCp@T) * dynamic viscosity (VViscosity) / thermal conductivity (VThermalCond)
LPrandtlNo Calc Prandtl’s number for the liquid phase = heat capacity (LmsCp@T) * dynamic viscosity (LViscosity) / thermal conductivity (LThermalCond)
LSurfaceTens Calc Surface Tension of the liquid phase.
IF97
WaterViscosity Calc The viscosity of pure water at the content temperature and pressure as calculated by IF97.
SteamViscosity Calc The viscosity of pure steam at the content temperature and pressure as calculated by IF97.