Gas-based reduction of vanadium titano-magnetite concentrate:behavior and mechanisms

来源 :International Journal of Minerals Metallurgy and Materials | 被引量 : 0次 | 上传用户:candle819
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
The reduction of vanadium titano-magnetite pellets by H_2–CO at temperatures from 850 to 1050°C was investigated in this paper. The influences of pre-oxidation treatment, reduction temperature, and V_(H_2)/(V_(H_2) + VCO) on the metallization degree were studied. The results showed that pre-oxidation played a substantial role in the reduction of vanadium titano-magnetite pellets. During the reduction process, the metallization degree increased with increasing temperature and increasing V_(H_2) /(V_(H_2) + VCO). The phase transformation of pre-oxidized vanadium titano-magnetite pellets during the reduction process under an H_2 atmosphere and a CO atmosphere was discussed, and the reduced samples were analyzed by scanning electron microscopy(SEM) in conjunction with back scatter electron(BSE) imaging. The results show that the difference in thermodynamic reducing ability between H_2 and CO is not the only factor that leads to differences in the reduction results obtained using different atmospheres. Some of Fe_(3-x)Ti_xO_4 cannot be reduced under a CO atmosphere because of the densification of particles’ structure and because of the enrichment of Mg in unreacted cores. By contrast, a loose structure of particles was obtained when the pellets were reduced under an H_2 atmosphere and this structure decreased the resistance to gas diffusion. Moreover, the phenomenon of Mg enrichment in unreacted cores disappeared during H_2 reduction. Both the lower resistance to gas diffusion and the lack of Mg enrichment facilitated the reduction of vanadium titano-magnetite. The reduction of vanadium titano-magnetite pellets by H 2 -CO at temperatures from 850 to 1050 ° C was investigated in this paper. The influences of pre-oxidation treatment, reduction temperature, and V_ (H_2) / (V_ (H_2) + VCO The reduction of vanadium titano-magnetite pellets. During the reduction process, the metallization degree increased increased with increasing temperature and increasing V_ (H_2) / (V_ (H 2) + VCO). The phase transformation of pre-oxidized vanadium titano-magnetite pellets during the reduction process under an H 2 atmosphere and a CO atmosphere was discussed, and the reduced samples were analyzed by scanning electron microscopy (SEM) in conjunction with back scatter electron (BSE) imaging. The results show that the difference in thermodynamic reducing ability between H_2 and CO is not the only factor that leads to differences in the reduction results obtained using differe Some of Fe_ (3-x) Ti_xO_4 can not be reduced under a CO atmosphere because of the densification of particles’ structure and because of the enrichment of Mg in unreacted cores. By contrast, a loose structure of particles was obtained when the pellets were reduced under an H 2 atmosphere and this structure decreased the resistance to gas diffusion. Moreover, the phenomenon of Mg enrichment in unreacted cores disappeared during H_2 reduction. Both the lower resistance to gas diffusion and the lack of Mg enrichment facilitated the reduction of vanadium titano-magnetite.
其他文献
随着电气自动化的应用越来越广泛,对它的技术要求也越来越高.这篇文章对我国的电气自动化的现状进行了分析,并进行了发展方向的研究,以期能达到推动电气自动化技术发展的效果
该文从挂篮荷载计算、施工流程、支座及临时固结施工、挂篮安装及试验、合拢段施工、模板制作安装、钢筋安装、混凝土的浇筑及养生、测量监控等方面人手,介绍了S226海滨大桥
该文从挂篮荷载计算、施工流程、支座及临时固结施工、挂篮安装及试验、合拢段施工、模板制作安装、钢筋安装、混凝土的浇筑及养生、测量监控等方面人手,介绍了S226海滨大桥
从社会物流总额,社会物流总费用及其与GDP的比例,配送、流通加工、包装等现代物流业务,物流增加值,物流固定资产投资等5个方面,对2005年上半年我国物流运行总体情况进行了分
本文首先阐述了液压机械控制系统的原理,接着分析了液压机械控制系统应用中的优缺点,进而分析了液压机械控制系统在机械设计制造中的应用实现,旨在说明液压机械控制系统在机