A unified approach to modelling wastewater chemistry: model corrections

Tait, Stephan, Solon, Kimberly, Volcke, Eveline I. P. and Batstone, Damien J. (2012). A unified approach to modelling wastewater chemistry: model corrections. In: Conference Proceedings: 3rd IWA/WEF Wastewater Treatment Modelling Seminar, WWTmod 2012. 3rd Wastewater Treatment Modelling Seminar (WWTmod2012), Mont-Sainte-Anne, Quebec, Canada, (51-62). 26-28 February 2012.

Attached Files (Some files may be inaccessible until you login with your UQ eSpace credentials)
Name Description MIMEType Size Downloads
Auth_copy.pdf Author copy application/pdf 344.00KB 192
Author Tait, Stephan
Solon, Kimberly
Volcke, Eveline I. P.
Batstone, Damien J.
Title of paper A unified approach to modelling wastewater chemistry: model corrections
Conference name 3rd Wastewater Treatment Modelling Seminar (WWTmod2012)
Conference location Mont-Sainte-Anne, Quebec, Canada
Conference dates 26-28 February 2012
Proceedings title Conference Proceedings: 3rd IWA/WEF Wastewater Treatment Modelling Seminar, WWTmod 2012
Place of Publication London, United Kingdom
Publisher International Water Association
Publication Year 2012
Sub-type Fully published paper
Start page 51
End page 62
Total pages 12
Collection year 2013
Language eng
Formatted Abstract/Summary
This contribution discusses preliminary approaches proposed by the IWA Task Group on a Generalised Physico-Chemical Modelling Framework. The emphasis is scientific and is to provide a mechanistic background on wastewater chemistry in support of wastewater treatment plant modelling done by the ASM-ADM type models. Model corrections are assessed, including ion activity, ion pairing and temperature effects on equilibrium constants. It is observed that selection of the correct activity coefficient model becomes critical at ionic strengths exceeding about 0.2 mol/kg. It is observed that ion-activity corrections are essential for correct model calculations of pH when the ionic strength of the wastewater exceeds about 0.2 mol/kg, and that ion pairing should be included for pH calculations above 0.7 mol/kg, or when solid-liquid precipitation reactions are being modelled. Lastly, the influence of temperature on chemical equilibrium is discussed for ions featuring in the ADM1 plus acid-base pairs of the inorganic phosphorus system. It is observed that the constant-enthalphy-form of the van’t Hoff relation provides equilibrium constants within 5% of experimentally measured values over a temperature range of 10-45°C, thus covering the relevant conditions of many wastewaters. A more complex constant-specific-heat-capacity form of the van’t Hoff relation can provide reliable equilibrium constant estimates over a wider temperature range of 0-60oC.
Keyword Physico-Chemical
Corrections
Ion activity
Ion association
Van't Hoff
Q-Index Code EX
Q-Index Status Confirmed Code
Institutional Status UQ

Document type: Conference Paper
Collections: Non HERDC
Advanced Water Management Centre Publications
 
Versions
Version Filter Type
Citation counts: Google Scholar Search Google Scholar
Created: Mon, 08 Oct 2012, 14:07:58 EST by Susan Cooke on behalf of Advanced Water Management Centre