Scholarlink

<p>To support green transition of vanadium titanomagnetite blast furnace smelting, various low-carbon blast furnace atmospheres, including oxygen-enriched air injection (CO–N<sub>2</sub>), oxygen-enriched H<sub>2</sub>-rich air injection (CO–H<sub>2</sub>), and H<sub>2</sub>-rich air injection (CO–H<sub>2</sub>–N<sub>2</sub>) were investigated to gain insight on the Ti(C,N) formation mechanisms. In this study, thermogravimetric analysis was first employed to investigate the kinetics of the TiO<sub>2</sub> reaction. Arrhenius-based kinetic modeling revealed that these reactions are primarily controlled by solid-state diffusion, and N<sub>2</sub> directly nitrides titanium oxides to TiN, and the activation energy decreases with increasing N<sub>2</sub> content. In contrast, H<sub>2</sub> lowers the activation energy of the reaction and promotes the reduction of TiO<sub>2</sub> to lower-valence oxides. Then, the carbothermic reduction of TiO<sub>2</sub>-bearing slags was investigated. Chemical composition analysis, XRD, and EPMA-WDS mapping demonstrated pronounced atmosphere-dependent variations in the formation of TiC/N phases. In CO–N<sub>2</sub> atmospheres, Ti(C,N) content decreases with increasing CO content and Ti(C,N) tends to agglomerate. With pure CO, only a few, sparsely dispersed TiC particles were detected. Whereas in CO–H<sub>2</sub> atmospheres, increasing the H<sub>2</sub> concentration markedly enhanced TiC formation, yielding uniformly dispersed particles with slight clustering. Therefore, the overall atmosphere effect on the amount of TiC/N formation follows the order: 100&#xa0;pct CO&#xa0;&lt;&#xa0;80&#xa0;pct CO–20&#xa0;pct H<sub>2</sub>&#xa0;&lt;&#xa0;80&#xa0;pct CO–20&#xa0;pct N<sub>2</sub>&#xa0;&lt;&#xa0;60&#xa0;pct CO–40&#xa0;pct H<sub>2</sub>&#xa0;&lt;&#xa0;60&#xa0;pct CO–40&#xa0;pct N<sub>2</sub>&#xa0;&lt;&#xa0;30&#xa0;pct CO–70&#xa0;pct N<sub>2</sub> atmosphere (conventional blast furnace atmosphere).</p> Graphical Abstract <p></p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Effect of Low-Carbon Atmosphere on Ti(C,N) Formation in Vanadium Titanomagnetite Blast Furnace

  • 期刊论文

  • 发表日期：

    2026年2月11日

查看全文
  • Buxin Chen,
  • Yehui Li,
  • Mao Chen,
  • Lingling Liu,
  • Kaihui Ma,
  • Chenguang Bai,
  • Meilong Hu

摘要

To support green transition of vanadium titanomagnetite blast furnace smelting, various low-carbon blast furnace atmospheres, including oxygen-enriched air injection (CO–N2), oxygen-enriched H2-rich air injection (CO–H2), and H2-rich air injection (CO–H2–N2) were investigated to gain insight on the Ti(C,N) formation mechanisms. In this study, thermogravimetric analysis was first employed to investigate the kinetics of the TiO2 reaction. Arrhenius-based kinetic modeling revealed that these reactions are primarily controlled by solid-state diffusion, and N2 directly nitrides titanium oxides to TiN, and the activation energy decreases with increasing N2 content. In contrast, H2 lowers the activation energy of the reaction and promotes the reduction of TiO2 to lower-valence oxides. Then, the carbothermic reduction of TiO2-bearing slags was investigated. Chemical composition analysis, XRD, and EPMA-WDS mapping demonstrated pronounced atmosphere-dependent variations in the formation of TiC/N phases. In CO–N2 atmospheres, Ti(C,N) content decreases with increasing CO content and Ti(C,N) tends to agglomerate. With pure CO, only a few, sparsely dispersed TiC particles were detected. Whereas in CO–H2 atmospheres, increasing the H2 concentration markedly enhanced TiC formation, yielding uniformly dispersed particles with slight clustering. Therefore, the overall atmosphere effect on the amount of TiC/N formation follows the order: 100 pct CO < 80 pct CO–20 pct H2 < 80 pct CO–20 pct N2 < 60 pct CO–40 pct H2 < 60 pct CO–40 pct N2 < 30 pct CO–70 pct N2 atmosphere (conventional blast furnace atmosphere).

Graphical Abstract