Corrosion of bauxite-based refractory castables and matrix components in hydrogen containing atmosphere

Abstract

For the transformation to a CO2 neutral industry, fuel of traditionally fossil-fired furnaces is substituted by the subsequently addition of hydrogen. In these studies, refractory components are identified for the corrosion of refractories in (highly) reducing atmospheres. A bauxite-based refractory castable is set up in diluted, 9Ar 1H2, hydrogen atmosphere. Additionally, a focus is set on the behavior of a common matrix phase, anorthite. Corrosion experiments up to 1500°C using a tube furnace with the mentioned atmosphere have been scheduled. Amount and phase stability due to different time and temperature coordinates have been examined by XRD. Furthermore, the microstructure and in particular the bonding phase was observed by means of SEM and EDS. Microstructural components undergoing reaction or loss are identified and explained in regards of complete and incomplete hydrogen combustion. Reduction of impurities such as iron oxides, phosphorus oxides, and titanium oxides are considered in detail.