Gasification of iron coke and cogasification behavior of iron coke and coke under simulated hydrogen-rich blast furnace condition

Abstract

To explore the iron coke application in hydrogen-rich blast furnace, which is an effective method to achieve the purpose of low carbon emissions, the initial gasification temperature of iron coke in CO₂ and H₂O atmosphere and its cogasification reaction mechanism with coke were systematically studied. Iron coke was prepared under laboratory conditions, with a 0–7wt% iron ore powder addition. The properties of iron cokes were tested by coke reactivity index (CRI) and coke strength after reaction (CSR), and their phases and morphology were evolution discussed by scanning electron microscopy and X-ray diffraction analysis. The results indicated that the initial gasification temperature of iron coke decreased with the increase in the iron ore powder content under the CO₂ and H₂O_(g) atmosphere. In the 40vol% H₂O + 60vol% CO₂ atmosphere, CRI of iron coke with the addition of 3wt% iron ore powder reached 58.7%, and its CSR reached 56.5%. Because of the catalytic action of iron, the reaction capacity of iron coke was greater than that of coke. As iron coke was preferentially gasified, the CRI and CSR of coke were reduced and increased, respectively, when iron coke and coke were cogasified. The results showed that the skeleton function of the coke can be protected by iron coke.

Keywords

iron coke / hydrogen-rich blast furnace / coke gasification / coke reactivity index / coke strength after reaction

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