Development of an optimum emissivity composite for refractories

Currently, a large part of the resources available for research are being directed towards the energy sector. The current demand for energy has led humanity to develop mechanisms and solutions that generate reductions in consumption and better utilisation of energy resources. In the steel industry, there are two pieces of equipment that are major consumers of energy in the form of combustible gases: blast furnace regenerators and slab or billet reheating furnaces. The basic function of refractories in this equipment is to withstand the high temperatures required by the process and keep the heat generated by the combustible gases inside the equipment. Following this line of research and with the aim of saving energy, a refractory composite doped with silicon carbide (SiC) and chromium oxide (Cr2O3) was developed, based on alumina (Al2O3) and silicon oxide (SiO2). This composite was used as a surface coating for the refractories and an increase in their thermal emissivity was obtained. The experiments confirmed that the specimens coated with the composite had a lower temperature than those that were not coated.