Structural Health Monitoring System for Furnace Refractory Wall Thickness Measurements at Cerro Matoso SA

In the smelting industry, the knowledge of the integrity of furnaces is a critical information because it allows well-informed decision-making during furnace operation, allows adjustments in furnace efficiency, and to prolong its remaining lifetime. To inspect furnace integrity, multiple methods have been explored. Particular characteristics of the furnace and the process make those solutions in most cases unique. This work explores the Ground Penetrating Radar-GPR method to evaluate the thickness of the refractory wall of an electric furnace during its operation in the production plant of Cerro Matoso SA, which is one of the world’s major producers of ferronickel. Results showed that the GPR method is limited by the metallic shield around the wall of the furnace because of the refraction of the signals, however a reliable measurement can be performed by locating the antenna in direct contact with the furnace’s refractory wall. In the latter configuration, it was possible to find different thicknesses at each measurement point and also to detect the phase boundary limit between the refractory wall and molten material.