2016-Sustainable Industrial Processing Summit
SIPS 2016 Volume 6: Yagi Intl. Symp. / Metals & Alloys Processing

Editors:Kongoli F, Akiyama T, Nogami H, Saito K, Fujibayashi A
Publisher:Flogen Star OUTREACH
Publication Year:2016
Pages:480 pages
ISBN:978-1-987820-46-1
ISSN:2291-1227 (Metals and Materials Processing in a Clean Environment Series)
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    Acceleration Mechanism of Reduction of Iron Ore-Carbon Composite by Increasing Pressure

    Taichi Murakami1; Hiroyuki Nagashima1; Qi Zhou1; Eiki Kasai2;
    1TOHOKU UNIVERSITY, Sendai, Japan; 2GRADUATE SCHOOL OF ENVIRONMENTAL STUDIES, TOHOKU UNIVERSITY, Sendai, Japan;
    Type of Paper: Keynote
    Id Paper: 61
    Topic: 3

    Abstract:

    Utilization of iron ore-carbon composite enables to play a significant role in reducing CO2 emission from the ironmaking process. However, its efficiency seems to be limited under the condition of the blast furnace. In this study, the effect of pressure from 0.1 to 8.0 MPa on the gasification and reduction of the composite was evaluated, and acceleration mechanism of reduction was discussed by mathematical simulation. The composite sample prepared using hematite reagent and graphite powder was heated up to different target temperatures at a heating rate of 0.167 ║C/s under different pressures. Under atmospheric pressure, reduction of composite sample started at approximately 900 ║C and completed at 1200 ║C. Starting temperature of reduction decreased with increasing pressure. At 1050 ║C, the effect of pressure on the reduction was most significant because gasification of graphite activated. To discuss the behavior, a mathematical simulation was carried out using Langmuir-Hinshelwood type gasification and unreacted-core models assuming that the temperature distribution in the composite sample can be neglected. Using the experimental data under atmospheric pressure, all parameters were decided, and the effect of pressure on the reduction was evaluated. Below 3.0 MPa, the calculated results were coincident with the measured one. It seems that reduction acceleration by increasing pressure is caused by an increase in the amount of adsorbed CO and O on carbon. Above 5.0 MPa and 1000 ║C, however, the latter was higher than the former. The reason may be that the temperature distribution cannot be neglected under higher pressure.

    Keywords:

    CO2; Composite; Iron;

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    Cite this article as:

    Murakami T, Nagashima H, Zhou Q, Kasai E. Acceleration Mechanism of Reduction of Iron Ore-Carbon Composite by Increasing Pressure. In: Kongoli F, Akiyama T, Nogami H, Saito K, Fujibayashi A, editors. Sustainable Industrial Processing Summit SIPS 2016 Volume 6: Yagi Intl. Symp. / Metals & Alloys Processing. Volume 6. Montreal(Canada): FLOGEN Star Outreach. 2016. p. 250-259.