Carburization Degree of Iron Nugget Produced by Rapid Heating of Powderly Iron, Iron Oxide in Slag and Carbon Mixture

Abstract

Iron nugget making process by rapid heating reduction of powdery iron ore and pulverized coal mixture is regarded as one of the novel ironmaking processes. Iron carburization during smelting reduction is especially important reaction step from the viewpoint of saving energy in this process. If the rate and efficiency of carburization reaction are increased, energy consumption of the process will be reduced to large extent. The purpose of this study is to clarify the carburization degree of iron nugget during smelting reduction of the mixture. The sample was prepared from graphite, electrolytic iron powder and synthetic slag containing iron oxide to simulate iron carburization phenomena during smelting reduction of the mixture in the present work. The sample was quenched immediately after the mixture changed into nugget shape in a rapid heating process. Laser microscope combined with infrared image furnace was used for sample heating and observation of carburization phenomena, and carbon content in the nugget was chemically analyzed after quenching. From above-mentioned investigations, it was revealed that the occurrence of carburization during smelting reduction in the sample mixture is advantageous to obtain higher carbon contain iron nugget.

Thermodynamic Modeling of the SFCA Phase Ca₂(Fe,Ca)₆(Fe,Al,Si)₆O₂₀

“…The consolidation of iron ore grains progresses with the formation of the Ca-Fe-O melt and material transportation through the melt, and is hence called liquidphase sintering. [1][2][3][4][5] The micro-texture of the sinter basically comprises the iron ore grains, bonding, pores, and cracks. The matrix of the bonding phases which precipitated from the Ca-Fe-O melt are composed of the calcium ferrites (CaO-Fe 2 O 3 ), silico-ferrites of calcium and aluminum, secondary hematite, magnetite, silicate glass (CaO-SiO 2 ), and their solid-solution phases, and these play an important role to give appropriate sinter properties such as strength and reducibility.…”

Effect of Ore Type and Gangue Content on Carburization and Melting Behavior of Carbon-Iron Ore Composite

“…Various studies on the melting behaviors of iron by carburization have been reported. [9][10][11][12] It was found that carburization through direct contact with solid carbon is more preferential than that with CO gas. 13) Carburization between metallic iron and carbonaceous materials proceeds…”