PH
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Navigation: User Guide ➔ Stream Properties ➔ Acidity (pH)
| Standard Species Model | Stream Properties | Special Cases | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| Standard Species Model | Stream Properties Calculations | Density | Heat of Formation | Heat of Dilution | Specific Heat (Cp) | Solubility | Boiling Point Elevation | pH | Charge | Steam and Water | Sulfuric Acid |
Overview
The pH of a liquid solution is the negative log of the Hydrogen ion molar concentration in solution at 25 degrees C. This is often the basis for calculating the pH of a solution. However, since SysCAD does NOT include calculations for buffering, this is an estimate of the pH only.
SysCAD uses the standard equation for autoionisation of water at 25 degrees C:
pKw = 14 = pH + pOH
where:
pH = -log[H+]
pOH = -log[OH-]
Implementation in SysCAD
- Entering pH Data in the Species Properties Database - A description of the Acid and Base Dissociation constants that can be entered or changed in the Species Properties Database.
- Displaying pH in a Project - The pH estimate can be displayed throughout a project by enabling the pH_Estimate tick box on the Views page in Plant Model (View - Plant Model - Views Tab).
- Estimate of pH in Units and Pipes - This describes the information shown in the access window of pipes, tanks, etc.
- Acid and Base Dissociation constants used in a Project - The Acid and Base Dissociation constants used in a project can be seen in the Species Database (Species - Edit Project Database).
- Acidity Calculations - This describes the methodology used to estimate the pH.
- Standard Acid and Base Dissociation constants in SysCAD - This gives some examples of the default Dissociation constants defined in SysCAD.