Blast furnace performance as influenced by burden distribution

Burden distribution is one of the key operating parameters influencing blas t furnace performance, particularly the productivity and the coke rate. The proper distribution of burden materials improves bed permeability, wind ac ceptance, and efficiency of gas utilisation. In furnaces operating with hig h coal injection rates, the distribution resulting in predominant central w orking (steep cohesive zone profile) was found to be beneficial. Since a hi gh coal injection rate increases the peripheral working (wall heat flux), a n attempt should be made to minimise the wall heat flux by striking a prope r balance between peripheral and central working. In a typical Indian blast furnace equipped with a bell-less (Paul Wurth) distribution system, the de crease in coke rate that is due exclusively to burden distribution was foun d to be 10-12 kg/thm.