EUROPEAN STEEL TECHNOLOGY AND APPLICATION DAYS 2017 - ESTAD 2017

Thermocouples are often installed in the blast furnace hearth, for use in estimating the remaining refractory thickness. However, a wide variety of thermocouple arrangements are used. Using a thermal assessment approach combining non-destructive testing (AU-E) and thermocouple data, the selection of thermocouple locations within a furnace hearth was investigated. 2D transient thermal analysis identified that the thermocouple arrangement may not identify transient changes to the system, as the thermal mass of refractory results in a slow response to process changes. It was found that 1D thermal calculations may under predict the extent of wear between thermocouples. 2D and 3D calculations were better able to predict the extent of wear. Results were later compared with AU-E measurement of refractory thickness. This assessment was used to provide recommendations to improve the thermocouple layout for refractory wear monitoring.