Fm. Meng et al., Reduction, carburization and melting behavior of iron ore pellets containing coal char or graphite on heating, TETSU HAGAN, 87(9), 2001, pp. 585-592
Citations number
16
Categorie Soggetti
Metallurgy
Journal title
TETSU TO HAGANE-JOURNAL OF THE IRON AND STEEL INSTITUTE OF JAPAN
Reactions in iron ore-coal char composite pellets heated in nitrogen atmosp
here at temperatures between 1100 degreesC and 1350 degreesC were investiga
ted. Coarsening and melting of reduced iron particles through their carburi
zation were furthermore investigated for iron ore-coal char (pellet P-c,P-l
) and iron ore-graphite (pellet P-g,P-i) composite pellets. Direct carburiz
aiton of iron in contact with carbon is superior to indirect carburization
through gas phase. Melting of P-c,P-l started above 1350 degreesC while mel
ting of P-g,P-i above 1200 degreesC. The mechanism of formation of core and
shell, which were observed for both kinds of the pellets by heating for a
certain time, was also discussed. Furthermore, heating experiments with ele
ctrolytic iron-coal char (pellet P-c,P-e) and electrolytic iron-graphite (p
ellet P-g,P-e) composite pellets in N-2 and CO-10%CO2 were conducted to stu
dy the effect of gasification of carbon on melting of the iron. It is concl
uded that the gasification of carbon has a strong effect on the carburizati
on by direct contact mechanism between iron and carbon, which finally deter
mines the melting starting temperature of reduced iron.