Two articles on thermal radiation conductivity of glass melts have been published to aid in the design of low carbon glass melting technologies.

Designing low carbon glass melting technologies requires reliable glass melt properties input data.

Accurate data is available on the viscosity behaviour of practically all industrial glasses.

However, the existing data on the thermal radiation conductivity of glass melts is scarce and often unreliable - especially the effects of temperature and redox on the radiation conductivity are unknown in many cases.

But from now, the guessing of this essential glass melt property is no longer necessary.

Two peer-reviewed articles with accurate models for quantifying the thermal radiation conductivity kR(T) of industrial silicate glass melts were recently published, see: Faber AJ et. al. in Int J Appl Glass Sci (2020*) & 2022**)), a journal of the American Ceramic Society.

For designing any industrial glass melting process, including low carbon melting technologies, by CFD modelling, the thermal transparency of the glass melt is a key property, next to viscosity.

For example, in electric glass furnaces, the transfer of the heat generated around the electrodes to the cold batch on top of the melt is strongly limited by the radiation conductivity of the melt.

A low radiation conductivity of the melt will result in a poor melting rate of the batch and thus in a low furnace pull rate.

The method for determining kR(T) has a sound scientific basis and can be applied to any silicate glass without or with (a combination of) the colouring ions Fe, Cr, Cu, Co, Mn and Ni.

For more information please contact: aj.faber@hotmail.com

After retiring from CelSian, and as Chairman of the Managing Board of Glass Trend, AJ Faber started his own scientific consultancy company for the glass industry called Physica Fit Faber.

References

*) Faber AJ et. al. Characterization of high temperature optical spectra of glass melts and modeling of thermal radiation conductivity, Int J Appl Glass Sci. 2020; 00:1-21. https://doi.org/10.1111/ijag.1...

**) Faber AJ et. al. High temperature near IR spectral properties and thermal radiation conductivity of (un)colored silicate glass melts, Int J Appl Glass Sci. 2022; 00:1-12. https://doi.org/10.1111/ijag.16603