Experimental Study of Blast Furnace Hearth Drainage Based on Image Analysis

A smooth hearth drainage is one of the key requirements for maintaining an efficient blast furnace operation. For achieving this, it is necessary to understand the hearth drainage behavior and the effect of related process parameters. To investigate the drainage, a set of experiments is conducted in a 2D Hele−Shaw model, where the influence of the initial accumulated amount of molten liquids (iron and slag), blast pressure, and slag viscosity on the drainage behavior is studied using water and oil as liquids. To quantify the findings, an image analysis-based algorithm is applied to extract drainage information that is used to analyze the effect of the mentioned process factors on the evolution of the liquid levels and volumes, flow rates, share oil in the outflow, and angle of the interfaces at the outlet. Herein, the implications of the results for the operation of the blast furnace hearth are discussed.