Effect of FeO concentration in sinter iron ore on reduction behavior in a hydrogen-enriched blast furnace  

作　　者：Ko-ichiro Ohno Takayuki Maeda Kazuya Kunitomo Masashi Hara 

机构地区：[1]Department of Materials,Faculty of Engineering,Kyushu University,744 Motooka,Nishi-ku,Fukuoka 819-0395,Japan [2]Kashima Area,East Nippon Works,Nippon Steel Corporation,3 Hikari,Kashima City,Ibaraki 314-0014,Japan

出　　处：《International Journal of Minerals,Metallurgy and Materials》2022年第10期1820-1829,共10页矿物冶金与材料学报（英文版）

基　　金：based on results obtained from the“CO_(2)Ultimate Reduction System for Cool Earth 50(COURSE50)Project”commissioned by the New Energy and Industrial Technology Development Organization(NEDO)。

摘　　要：Japan started the national project“COURSE 50”for CO_(2) reduction in the 2000s.This project aimed to establish novel technologies to reduce CO_(2) emissions with partially utilization of hydrogen in blast furnace-based ironmaking by 30%by around 2030 and use it for practical applications by 2050.The idea is that instead of coke,hydrogen is used as the reducing agent,leading to lower fossil fuel consumption in the process.It has been reported that the reduction behavior of hematite,magnetite,calcium ferrite,and slag in the sinter is different,and it is also considerably influenced by the sinter morphology.This study aimed to investigate the reduction behavior of sinters in hydrogen enriched blast furnace with different mineral morphologies in CO-CO_(2)-H2 mixed gas.As an experimental sample,two sinter samples with significantly different hematite and magnetite ratios were prepared to compare their reduction behaviors.The reduction of wustite to iron was carried out at 1000,900,and 800℃ in a CO-CO_(2)-H2 atmosphere for the mineral morphology-controlled sinter,and the following findings were obtained.The reduction rate of smaller amount of FeO led to faster increase of the reduction rate curve at the initial stage of reduction.Macro-observations of reduced samples showed that the reaction proceeded from the outer periphery of the sample toward the inside,and a reaction interface was observed where reduced iron and wustite coexisted.Micro-observations revealed three layers,namely,wustite single phase in the center zone of the sample,iron single phase in the outer periphery zone of the sample,and iron oxide-derived wustite FeO and iron,or calcium ferritederived wustite'FeO'and iron in the reaction interface zone.A two-interface unreacted core model was successfully applied for the kinetic analysis of the reduction reaction,and obtained temperature dependent expressions of the chemical reaction coefficients from each mineral phases.

关 键 词：HYDROGEN reduction WUSTITE HEMATITE MAGNETITE calcium ferrite two-interface unreacted core model COURSE50 

分 类 号：TF533[冶金工程—钢铁冶金]