Slag detection system based on infrared temperature measurement

Abstract In order to detect the slag content in the pouring or tapping stream of a basic oxygen furnace (BOF), a slag detection system is designed. The temperature of pouring stream is measured using the infrared temperature measurement system. The molten steel and slag could be distinguished according to their infrared emissivities that have a great difference in far-infrared band. A calibration method for the temperature threshold that is used to distinguish the molten steel and slag in a certain environment is proposed and the amount of slag is calculated in real-time. To avoid the situation that the amount of slag is incapable of being calculated due to the change of BOF angle (moving of pouring stream), a method that can quickly find the edge of the pouring stream is applied to implement the tracking of molten steel pouring stream. Experimental results prove that this system is effective to control the amount of slag that comes into the ladle.