Thermal state simulation analysis of molten iron ladle based on different insulation measures

The turnover time for transporting a hot metal from a blast furnace to a basic oxygen furnace is long and therefore the heat preservation effects are not ideal. These factors affect the temperature and thermal state of the ladle refractories, which leads to the heat loss of the hot metal. Reducing the temperature drop of the hot metal can effectively prevent the hot metal nodules and decrease the frequency of offline baking; moreover, it indirectly increases the turnover rate of the hot metal ladle. At the same time, a hot metal with low temperature seriously affects the addition amount of scrap steel and oxygen blowing operations during the smelting process in the converter. Therefore, it can be observed that controlling the hot metal temperature is one of the key factors for energy saving and efficient production in a steel plant. To reduce the temperature drop of a hot metal, a variety of computation models of ladles with several insulation measures were established. In addition, the Ansys fluent software was used to simulate the temperature fields after the end of the charging. The influence of thermal states of ladles with different insulation measures and unloaded time on the temperature drop of the hot metal was investigated. The analysis shows that reducing the unloaded time from 5 h to 3 h can decrease the temperature loss of the hot metal by 2.2 K·h^-1. Using a ladle with an insulation layer of about 6 mm and an insulation cap is the most sensible measure to realize insulation. It can increase the average temperature of a working layer by almost 155 K, and this improvement can reduce the temperature loss of hot metal by 3.4-3.7 K·h^-1 during the 3 to 5 h unloaded time. The conclusions provide some academic bases and references for the reasonable insulation measures and control of the unloaded time of a multifunctional hot metal ladle.