欢迎访问过程工程学报, 今天是

过程工程学报 ›› 2023, Vol. 23 ›› Issue (4): 544-553.DOI: 10.12034/j.issn.1009-606X.222135

• 研究论文 • 上一篇    下一篇

铁矿粉烧结被覆型准颗粒燃烧特性及动力学分析

韩涛, 胡长庆*, 卢超群
  

  1. 华北理工大学冶金与能源学院,河北 唐山 063210
  • 收稿日期:2022-04-15 修回日期:2022-06-06 出版日期:2023-04-28 发布日期:2023-05-04
  • 通讯作者: 胡长庆 hiq73@163.com
  • 作者简介:韩涛,博士研究生,高级工程师,冶金工程,E-mail: ht_085@163.com;通讯联系人,胡长庆,教授,主要从事冶金原料预处理技术、冶金节能与资源优化等领域的教学与研究,E-mail: hiq-73@163.com
  • 基金资助:
    国家自然科学基金资助项目;河北省自然科学基金-钢铁联合基金

Combustion characteristics and kinetic analysis of coated quasi-particles in iron ore fines sintering

Tao HAN,  Changqing HU*,  Chaoqun LU   

  1. School of Metallurgy and Energy, North China University of Science and Technology, Tangshan, Hebei 063210, China
  • Received:2022-04-15 Revised:2022-06-06 Online:2023-04-28 Published:2023-05-04
  • Contact: HU Changqing hiq73@163.com

摘要: 为研究铁矿粉烧结过程黏附粉成分对焦炭颗粒燃烧的影响规律,以粒径2~3 mm的焦粉颗粒为核颗粒,采用Al2O3, SiO2, CaO, MgO, Fe2O3纯试剂以及人工合成CaO?Fe2O3 (CF)替代铁矿粉作为黏附粉,分别制备成不同成分黏附层的被覆型准颗粒(S型),采用热重分析法开展非等温燃烧实验和燃烧特性分析,利用Coats-Redfern法求解燃烧反应最概然机理函数,建立动力学物理模型进行动力学解析。结果表明,黏附层成分显著影响准颗粒的燃烧特性,CaO, CF, Fe2O3具有较强的催化燃烧作用,可显著降低焦炭颗粒的着火点,降低燃烧温度,提高燃烧效率和转化速率,而MgO的催化能力较弱,催化能力由高到低依次为CaO>CF>Fe2O3>MgO。S型准颗粒在快速燃烧阶段的最概然机理函数为R3,建立并解析了准颗粒燃烧的球对称未反应收缩核物理模型,在快速燃烧阶段碳-氧界面反应向核心推进,界面反应速率小于内扩散速率,是影响准颗粒燃烧速率的控制性环节。

关键词: 被覆型, 准颗粒, 催化燃烧, 燃烧特性, 动力学

Abstract: Iron ore fines sintering, as the main atmospheric pollution source of blast furnace-converter long process steel production, is facing the pressure and challenge of ultra-low emission under the background of carbon peaking and carbon neutrality. Solid fuel exists in the sintering layer of iron ore fines in various forms, and the mass fraction of the coated quasi-particles (S-type) is as high as 70%. Therefore, the S-type quasi-particles were taken as the research object, the influence of adhesion fines composition on coke combustion were analyzed, and the dynamic rate control link was clarified, which provided a theoretical basis for improving combustion efficiency. The coke particles with 2~3 mm particle size were used as the core particles, and Al2O3, SiO2, CaO, MgO, Fe2O3 pure reagents and synthetic CaO-Fe2O3 (CF) were used to replace iron ore fines as adhesion fines. Then, S-type with different composition adhesion layers were prepared respectively. The non-isothermal combustion test and combustion characteristics were studied by thermogravimetric analysis. The most probable mechanism function of combustion reaction was solved by Coats-Redfern method, and the kinetic physical model was established for kinetic analysis. The results showed that the combustion characteristics of quasi-particles were significantly affected by the composition of adhesive layer. CaO, CF and Fe2O3 had strong catalytic combustion effect. The ignition point and combustion temperature of coke particles were significantly reduced, and the combustion efficiency and conversion rate were improved. The catalytic ability of MgO was weak, and the catalytic ability from high to low was CaO>CF>Fe2O3>MgO. The most probable mechanism function of S-type quasi-particles in the rapid combustion stage was R3, the spherically symmetric unreacted shrinking nuclear model of quasi-particle combustion was established and analyzed. In the rapid combustion stage, the carbon-oxygen interface reaction advanced to the core, and the interface reaction rate was smaller than the internal diffusion rate, which was the control link affecting the combustion rate of quasi-particles.

Key words: coated type, quasi-particles, catalytic combustion, combustion characteristics, kinetics