What is GPS-X?
Wastewater Process Libraries
Technical Specifications


GPS-X incorporates the latest developments in wastewater process model technology to provide you with a comprehensive and realistic model of your treatment plant. Each wastewater model library is available in two versions: Basic and Full. The Full library includes all of the wastewater process objects included in the Basic version plus additional unit processes.


For modelling carbon oxidation, nitrification and denitrification.

Carbon-Nitrogen- Phosphorus

Builds on the Carbon-Nitrogen library by including models for biological AND chemical phosphorus removal.

Advanced Carbon- Nitrogen

Similar to Carbon - Nitrogen library, but fate of nitrite and nitrite nitrogen are modelled separately. Also includes inert nitrogen (both soluble and particulate form) and inert non-volatile solids (ash).

Industrial Pollutant

Combines Carbon-Nitrogen library and 30 user definable components. Required for industrial wastewater treatment applications.

Advanced Industrial Pollutant

Combines the Advanced Carbon-Nitrogen library with the Industrial Pollutant library.


Contains 15 fully customizable components. Possible applications include modelling of paper production, chemical industry processes, petroleum, etc.

GPS-X Process Table
Process object titles in blue indicate additional objects available in Full version.
Settlers and clarifiers in Basic version are one dimensional and non-reactive.
Full version adds 2 dimensional reactive capability.

Wastewater Components Available in ALL Libraries

Wastewater Components Wastewater Components Specific To Anaerobic Digestion

Soluble carbonaceous BOD5
Particulate carbonaceous BOD5
Total carbonaceous BOD5
Total carbonaceous BOD20
Soluble COD
Particulate COD
Total COD
Soluble TKN
Total nitrogen (TN)
Inert non-volatiles
Volatile suspended solids (VSS)
Suspended solids (TSS)

*Advanced Carbon-Nitrogen and Advanced Industrial Pollutant libraries only

Inert non-volatiles
Heterotrophic methanogens
Volatile Suspended Solids (VSS)
Volatile Fatty Acids (VFA)
Total carbon dioxide (CO2)
CO2 in gas phase
Toxic material
Ammonium + ammonia nitrogen
Net cations
Methane gas

Library-Specific Wastewater Components

Wastewater Components CN CNP IP Adv. CN Adv. IP Open
Oxygen yes yes yes yes yes  
Inert particulate organic material yes yes yes yes yes  
Inert soluble organic material yes yes yes yes yes  
Slowly bio-degradable substrates yes yes yes yes yes  
Soluble hydrolizable substrates       yes yes  
Readily bio-degradable organic substrates yes yes yes yes yes  
Fermentable soluble substrates   yes        
Volatile fatty acids (VFA)   yes        
Inert non-volatile solids (ash)       yes yes  
Bacteria decay products yes yes yes yes yes  
Cell internal storage products yes          
Stored glycogen   yes        
Particulate biodegradable nitrogen yes yes yes yes yes  
Soluble biodegradable nitrogen yes yes yes yes yes  
Ammonium + ammonia nitrogen yes yes yes yes yes  
Nitrate+nitrite nitrogen yes yes yes      
Nitrite nitrogen       yes yes  
Nitrate nitrogen       yes yes  
Dinitrogen yes yes        
Particulate inert nitrogen       yes yes  
Soluble inert nitrogen   yes   yes yes  
Soluble phosphorus   yes        
Poly-hydroxy-alkanoates (PHA)   yes        
Stored polyphosphate (fixed)   yes        
Stored polyphosphate (releasable)   yes        
Heterotrophic organisms yes yes yes yes yes  
Nitrifying organisms yes yes yes      
Nitrosomanas organisms       yes yes  
Nitrite-oxidising organisms       yes yes  
Phosphate-accumulating organisms (PAO)   yes        
Metal-hydroxides   yes        
Metal-phosphate (MePO4)   yes        
Alkalinity yes yes   yes yes  
10 user definable states         yes  
15 user definable states           yes
30 user definable states     yes