Evaluation of Burden Descent Model for Burden Distribution in Blast Furnace

Mathematical models for burden descending process have been applied to obtain whole burden structures in blast furnace, whereas the accuracy of those burden descent models has not been sufficiently investigated. Special evaluation method based on timeline burden profiles was established to quantitatively evaluate the error between experimental and modeled burden structures. Four existing burden descent models were utilized to describe the burden structure of a 1/20 sealed warm blast furnace. Input modeling conditions including initial burden profile, descending volumes in each time interval, and normalized descending velocity distribution were determined via special image processing technology. Modeled burden structures were evaluated combined with the published experimental data. It is found that all the models caught the main profile of the burden structure. Furthermore, the improved nonuniform descent model (Model IV) shows the highest level of precision especially when burden descends with unstable velocity distribution tendency. Meanwhile, the traditional nonuniform descent model (Model III) may also be desirable to model the burden descending process when the burden descending velocity presents a linear tendency. Finally, the uniform descent model (Model I) might be the first option for roughly predicting burden structure.