17th Furnace Solutions

New fused-cast refractories to extend lifetime of net-zero carbon glass furnaces

The path to net-zero carbon furnaces will require new melting technologies, such has hybrid furnaces, higher boosting, high pull full electric-furnaces and very probably hydrogen-fired oxyfuel furnaces. These new technologies will result in harsher operating conditions such as higher temperature with large temperature variations, faster local glass convection and modification of the furnace atmosphere composition. All these changes will be significantly impacting the refractories.

To better understand these changes, specific laboratory trials must be designed to reproduce operating conditions of this new generation of furnaces and quantify their impact on refractories.

Then, as a stronger corrosion is expected on these furnaces, leading to shorter lifetime and higher risk of premature shut down, a new generation of refractories is being developed. The purpose of the second part of this paper is to highlight the benefits of a new generation of fused cast refractory with high zirconia content but also with a significant alumina rate. This completely new type of materials combines a much higher corrosion resistance in comparison to current AZS without increasing the sensitivity to upward drilling mechanisms affecting the high zirconia products. It also ensures to maintain the required quality of glass without generating stoning or any coloration issue.

Tests at lab-scale are first described to assess the excellent performances of this material in terms of corrosion resistance and its impact on glass quality; then first successful product installation as a throat and as a soldier block are presented.

Author & Affiliation: Pierrick Vespa, Research and Development Engineer for SEFPRO
SGR Provence, Cavaillon, France