LD converter test bench for slopping detection using lance vibration analysis

The steelmaking industry is led by the Basic Oxygen Steelmaking process, where LD (Linz-Donawitz) converters are used to produce steel. During the process, foam is generated inside the converter by the reactions between the oxygen blow and the metallic charge. The foam formation is required for the process, but if it grows excessive, it can overflow out of the vessel top and cause serious problems to the whole process, thus controlling the foam formation is essential. The industry has different methods for detecting this event, but they can be unreliable in certain conditions. However, using more than one method together may produce a more consistent detection system. This work presents a method for slopping detection on LD converters using lance vibration that is part of a under development multi sensor system. A test bench was built for simulating the oxygen blow and experiments were performed to test the method. The results have shown a strong correlation between lance vibration and foam height, which made possible the foam height estimation and, thereafter, the slopping detection.