Material Content Section - pH, Charge and Transport Properties

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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

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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.