The effective volume of 7^# blast furnace of Baotou Steel is 4 150 m³. On October 23rd, 2022, it was blown down for gunning of lining and remolding inner profile. In the blowing down, the method of dropping stockline by spraying water was adopted and the stockline was dropped to a position below center line of tuyere. The methods of reducing the basicity of furnace slag ahead of time and increasing furnace temperature were taken to increase wall temperature, the match of air and oxygen quantities and assessment method of depth of stockline different from the past as well as the method of spraying water, that is, monitoring the mean value and difference value trend of four points of top temperature to control the water quantity were adopted. After taking the above measures, stockline could be dropped safely and rapidly.

blast furnace  /  drop stockline  /  blow down