Article
Metallurgy & Metallurgical Engineering
Qi-yan Xu, Zhang-han Gu, Zhi-ping Li, Ying-yi Zhang, Hai-chuan Wang
Summary: The optimal operating parameters for pure hydrogen reduction and addition of plastic particles during fluidized bed reduction of fine iron ore were determined. It was observed that the chemical reaction resistance and inner diffusion resistance changed over time during the reduction process.
JOURNAL OF IRON AND STEEL RESEARCH INTERNATIONAL
(2021)
Article
Engineering, Chemical
Zhan Du, Yu Ge, Fan Liu, Chuanlin Fan, Feng Pan
Summary: Different modification methods were studied to enable the direct reduction of iron ore fines in a fluidized bed. Granulation modification was found to be an effective and general solution, improving the reduction rate and preventing defluidization issues.
Article
Chemistry, Physical
Thomas Wolfinger, Daniel Spreitzer, Johannes Schenk
Summary: This article focuses on the use of iron ore ultra-fines in a novel hydrogen-based fluidized bed direct reduction process, analyzing the benefits of this process and the classification of iron ore ultra-fines in a fluidized bed. The effects of process conditions and the agglomeration phenomenon sticking on the fluidized bed were analyzed and evaluated with mathematical case studies, identifying sticking as the most critical issue.
Article
Engineering, Environmental
Zhan Du, Jiayi Liu, Fan Liu, Feng Pan
Summary: The relationship between particle size, reaction, and sticking behavior of iron ore fines in fluidized bed hydrogen reduction was systematically investigated. The study found that hydrogen reduction of granulated iron ore was controlled by reduction reaction, and the activation energy was approximately 88.4 kJ/mol. It was also found that the defluidization temperature of granulated iron ore can be raised by increasing the particle size. The maximum gas utilization rate of fluidized bed hydrogen reduction was estimated by coupling the kinetic model and force balance model.
CHEMICAL ENGINEERING JOURNAL
(2022)
Review
Chemistry, Physical
Thomas Wolfinger, Daniel Spreitzer, Johannes Schenk
Summary: This review examines the usability of iron ore ultra-fines for hydrogen-based direct reduction, aiming to reduce CO2 emissions and energy consumption in the iron and steel industry. The classification of powders for fluidized bed and the fluid dynamics related to the processing of iron ore ultra-fines are analyzed. The impact of the reduction process and methods to prevent sticking are also evaluated. Theoretical considerations and process-relevant issues for utilizing iron ore ultra-fines in hydrogen-based fluidized bed direct reduction are provided.
Article
Engineering, Chemical
Jianwen Yu, Yang Ou, Yongsheng Sun, Yanjun Li, Yuexin Han
Summary: The reduction effect and product characteristics of vanadium titanomagnetite ore using hydrogen as reductant under fluidized bed conditions were investigated. The reduced product with a metallization degree of 90.22% was obtained under the optimal conditions, and no FeO was detected during the reduction process.
Article
Materials Science, Multidisciplinary
Heng Zheng, Oday Daghagheleh, Thomas Wolfinger, Bernd Taferner, Johannes Schenk, Runsheng Xu
Summary: This study investigated the impact of different pre-oxidation temperatures and degrees on the reduction and fluidization behaviors of magnetite-based iron ore. It was found that higher oxidation temperatures and wider particle size ranges resulted in better fluidization behaviors, while lower oxidation temperatures were more conducive to reduction rates. Pre-oxidation degrees did not have a significant influence on fluidization and reduction behaviors.
INTERNATIONAL JOURNAL OF MINERALS METALLURGY AND MATERIALS
(2022)
Review
Engineering, Chemical
Rahul K. Soni, Eswaraiah Chinthapudi, Sunil K. Tripathy, Manaswita Bose, Partha S. Goswami
Summary: Steel production is a significant pillar of many economies. The conversion of hematite to magnetite through high temperature control is considered as an alternative technology. This article provides a comprehensive review of the scientific and engineering developments on the reduction-roasting of iron-ore and the modeling and simulation work performed to reduce iron ore to magnetite.
REVIEWS IN CHEMICAL ENGINEERING
(2023)
Article
Materials Science, Multidisciplinary
Heng Zheng, Johannes Schenk, Oday Daghagheleh, Bernd Taferner
Summary: Hydrogen-based direct reduced iron (HyDRI) produced by fluidized bed shows great potential for achieving net-zero carbon in steelmaking. However, the use of magnetite ores as feedstock affects its fluidization and reduction behaviors. This study conducted an orthogonal experimental method to identify the dominant influencing factors and determine the optimum process conditions. The results indicate that oxidation temperature, oxidation content, MgO addition amount, and gas velocity are the primary and secondary influencing factors, with the optimum condition being deep oxidation of magnetite iron ore at 800 degrees C, mixed with 1.5 wt.% of MgO powder, and reduced in a fluidized bed at a gas velocity of 0.45 m/s.
Article
Materials Science, Multidisciplinary
Chuanfu Li, Yan Liu, Yuelong Wu, Ting'an Zhang
Summary: Hydrogen metallurgy is a technology that uses hydrogen as a reducing agent to reduce CO2 emissions, which is beneficial for the sustainable development of the steel industry. This study focused on solving the sticking problem in hydrogen reduction fluidized ironmaking technology using a fluidized bed with an inclined agitator as the reactor. The effects of agitation speed and reduction temperature on the fluidization state of iron concentrate particles were investigated through a single-factor experiment. The results indicated that adding an inclined agitator effectively reduced the sticking ratio and maintained fluidization of iron concentrate particles during the reduction process, thus improving the reduction efficiency. The optimal agitation speed was 160 rpm, and the optimum reduction temperature was 1123 K.
Article
Energy & Fuels
Dennis Y. Lu, Yewen Tan, Marc A. Duchesne, David McCalden
Summary: Biomass, a complex fuel containing organic and inorganic matter, can cause ash-related problems in combustion systems. This study focuses on estimating the potential for potassium absorption by bed materials in high-potassium biomass fuel combustion. Experiments were conducted to examine the effects of various factors on potassium capture. The results show that temperature and potassium salt type have a significant impact on potassium capture, while the gas atmosphere has a less notable effect.
Article
Engineering, Environmental
Zheng Zou, Yu Ge, Jingyi Zhu, Junwu Wang, Qingshan Zhu, Hongzhong Li
Summary: This study analyzed the application of MCFBR for the reduction of MnO2 ore and established a computational model for the hydrodynamics and reaction characteristics of multi-chamber fluidized bed. The simulation results showed that the model could accurately calculate the gas-solid reaction behavior compared to the traditional model. Furthermore, the quantitative effects of partition configuration, fluidized structure, and operating condition on the solids conversion rate were estimated.
CHEMICAL ENGINEERING JOURNAL
(2023)
Article
Engineering, Chemical
Jianwen Yu, Nan Hu, Hanxin Xiao, Peng Gao, Yongsheng Sun
Summary: A new efficient and clean utilization technique for vanadium-titanium magnetite based on fluidized bed hydrogen reduction was developed in this study. Experimental results showed that a high metallization degree could be obtained under specific conditions, and the aggregation of metallic iron grains into flakes was observed during the reduction process.
Article
Materials Science, Multidisciplinary
Daniel Ernst, Ubaid Manzoor, Isnaldi Rodrigues Souza Filho, Michael Andreas Zarl, Johannes Schenk
Summary: In order to mitigate the increasing greenhouse gas emissions, particularly CO2, the European steel industry needs to restructure its current steel production process. Hydrogen Plasma Smelting Reduction (HPSR) technology, which utilizes excited hydrogen states, has the potential to reduce CO2 emissions. Through a series of experiments, it was found that pre-reduced iron ore and iron-containing residues have an impact on reduction behavior, hydrogen consumption, process time, and metal phase microstructure. Magnetite ore exhibited the highest reduction rate and hydrogen conversion rates, while hematite experienced a decrease in reduction rate after reaching a certain degree. The combination of HPSR and fluidized bed technology can be advantageous for exhaust gas recycling.
Article
Engineering, Chemical
Junying Wan, Tiejun Chen, Xianlin Zhou, Yanhong Luo, Wei Liu, Qicai Lu
Summary: The study found that the addition of high-manganese iron ore can promote the direct reduction process of high-iron red mud and increase the metallization rate.
MINERALS ENGINEERING
(2021)