|Standard Species Model||Stream Properties||Special Cases|
|Density||Heat of Formation||Heat of Dilution||Specific Heat |
|Solubility||Boiling Point Elevation||pH||Charge||Steam and Water||Sulfuric Acid|
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
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.