Investigation of the microstructure interaction mechanism of coke–slag–metal in deadman of blast furnace

ABSTRACT

Coke–slag–metal samples located near the deadman edge and below the taphole of blast furnace were obtained by core drilling after cooling. The chemical composition, microstructure, phase composition and distribution of samples were studied in detail. In addition, the graphitisation degree of coke in hearth was also investigated. The results showed that coke larger than 60 mm still existed (more than 1%). Pores in coke are filled with molten slag and a small part of liquid iron. The pores in hearth coke are not completely filled, but there is still plenty of micropore, with a volume of less than 1 mm³. There are also a little alkali metals (K and Na) in ash, which causes the deterioration of coke. The iron–carbon interface is covered by a slag layer. The coke remained in deadman long enough to undergo the graphitisation process.

KEYWORDS:

• Coke d
• deadman
• slag–iron–coke
• interaction
• Micro-CT detection
• graphitisation
• deterioration
• micropore

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was part of a research project named ‘The dissolution behaviour and carburising ability of coke dissolution in hot metal’ supported by the National Natural Science Foundation of China [Grant number 51774032], the National Key Research and Development Program of China [Grant numbers 2017YFB0304300 & 2017YFB0304303].