Thermodynamic database for performance assessment: ThermoChimie

Our Team holds an excellent knowledge in thermodynamics and its application. Nearly since its beginning (2000), Amphos 21 has been heavily involved in the development, update and maintenance of the ThermoChimie database (, Giffaut et al. 2014).

ThermoChimie is a world reference thermodynamic database used in calculations supporting the performance assessment of radioactive waste repositories. It was created by Andra (the French National Radioactive Waste Management Agency), in 1995. In October 2014, Radioactive Waste Management Limited (NDA, UK) joined the project and the “ThermoChimie consortium” was formed. They were joined in March 2018 by Ondraf/Niras (National Agency for Radioactive Waste Management, Belgium). 

The tasks fulfilled by Amphos 21 include, among others:

  • the update and revision of the thermodynamic data included in ThermoChimie
  • extensive verification and validation work
  • fulfil the consistency and usability requirements of the database
  • studies to evaluate specific conditions of the near field of radioactive waste, in particular regarding temperature increase and release of organic ligands or soluble salts.