ISIJ International
Online ISSN : 1347-5460
Print ISSN : 0915-1559
ISSN-L : 0915-1559
Regular Article
Investigation of Coke Collapse in the Blast Furnace Using Mathematical Modeling and Small Scale Experiments
Tamoghna MitraHenrik Saxén
Author information
JOURNALS OPEN ACCESS FULL-TEXT HTML

2016 Volume 56 Issue 9 Pages 1570-1579

Details
Abstract

Burden distribution plays a key role in controlling the gas flow conditions inside a blast furnace. The distribution of ore and coke influences the gas permeability distribution in the lumpy zone and also in the cohesive zone, where the gas flows mainly through the coke slits. Charging an ore dump on coke can sometimes cause the coke layer to collapse under the force of the heavier ore particles. This is known as ‘coke collapse’ or ‘coke push’, which results in a higher coke fraction near the center of the furnace than expected. In this work coke collapse phenomena are evaluated on model charging programs using small scale experiments and Discrete Element Modeling (DEM). DEM simulations were used to study the extent of collapse for different charging programs, and experiments were undertaken to verify the results of the simulations. The slope stability method was used to classify the collapse conditions into no collapse, impact failure or gravity failure, depending on the stability of the coke layer. The findings were also compared with results from an in-house mathematical model, which was modified to consider the effect of the collapse on the underlying layer. The corrected mathematical model was found to show results in general agreement with results from the DEM simulation.

Factor of safety for the coke layers in the charging programs CP1–CP5 as the coke apex is moved towards the furnace center. The cross and the circle indicate the initial and the final factor of safety calculated using the correction scheme. Fullsize Image
Information related to the author
© 2016 by The Iron and Steel Institute of Japan
Previous article Next article
feedback
Top