scholarly journals Detailed Modeling of the Direct Reduction of Iron Ore in a Shaft Furnace

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1865 ◽  
Author(s):  
Hamzeh Hamadeh ◽  
Olivier Mirgaux ◽  
Fabrice Patisson
Keyword(s):  
Iron Ore ◽  
Shaft Furnace ◽  
Direct Reduction ◽  
Central Zone ◽  
Reduction Process ◽  
Furnace Operation ◽  
Direct Reduction Of Iron ◽  
Energy And Momentum ◽  
Thermal Phenomena ◽  
Volume Method

This paper addresses the modeling of the iron ore direct reduction process, a process likely to reduce CO2 emissions from the steel industry. The shaft furnace is divided into three sections (reduction, transition, and cooling), and the model is two-dimensional (cylindrical geometry for the upper sections and conical geometry for the lower one), to correctly describe the lateral gas feed and cooling gas outlet. This model relies on a detailed description of the main physical–chemical and thermal phenomena, using a multi-scale approach. The moving bed is assumed to be comprised of pellets of grains and crystallites. We also take into account eight heterogeneous and two homogeneous chemical reactions. The local mass, energy, and momentum balances are numerically solved, using the finite volume method. This model was successfully validated by simulating the shaft furnaces of two direct reduction plants of different capacities. The calculated results reveal the detailed interior behavior of the shaft furnace operation. Eight different zones can be distinguished, according to their predominant thermal and reaction characteristics. An important finding is the presence of a central zone of lesser temperature and conversion.

scholarly journals Detailed Modeling of the Direct Reduction of Iron Ore in a Shaft Furnace

2018 ◽  
Author(s):  
Hamzeh Hamadeh ◽  
Olivier Mirgaux ◽  
Fabrice Patisson
Keyword(s):  
Iron Ore ◽  
Shaft Furnace ◽  
Direct Reduction ◽  
Central Zone ◽  
Reduction Process ◽  
Furnace Operation ◽  
Direct Reduction Of Iron ◽  
Energy And Momentum ◽  
Thermal Phenomena ◽  
Volume Method

This paper addresses the modeling of the iron ore direct reduction process in the context of the reduction in CO2 emissions from the steel industry. The shaft furnace is divided into three sections (reduction, transition, and cooling), and the model is two-dimensional (cylindrical geometry for the upper sections and conical geometry for the lower one) to correctly describe the lateral gas feed and the cooling gas outlet. This model relies on a detailed description of the main physical-chemical and thermal phenomena using a multi-scale approach. The moving bed is assumed to be comprised of pellets of grains and crystallites. Eight heterogeneous and two homogeneous chemical reactions are taken into account. The local mass, energy and momentum balances are numerically solved using the finite volume method. This model was successfully validated by simulating the shaft furnaces of two direct reduction plants of different capacities. The calculated results reveal the detailed interior behavior of the shaft furnace operation. Eight different zones can be distinguished according to their predominant thermal and reaction characteristics. An important finding is the presence of a central zone of lesser temperature and conversion.

scholarly journals Detailed Modeling of the Direct Reduction of Iron Ore in a Shaft Furnace

2018 ◽  
Author(s):  
Hamzeh Hamadeh ◽  
Olivier Mirgaux ◽  
Fabrice Patisson
Keyword(s):  
Iron Ore ◽  
Shaft Furnace ◽  
Direct Reduction ◽  
Central Zone ◽  
Reduction Process ◽  
Furnace Operation ◽  
Direct Reduction Of Iron ◽  
Energy And Momentum ◽  
Thermal Phenomena ◽  
Volume Method

This paper addresses the modeling of the iron ore direct reduction process, a process likely to reduce CO2 emissions from the steel industry. The shaft furnace is divided into three sections (reduction, transition, and cooling), and the model is two-dimensional (cylindrical geometry for the upper sections and conical geometry for the lower one), to correctly describe the lateral gas feed and cooling gas outlet. This model relies on a detailed description of the main physical–chemical and thermal phenomena, using a multi-scale approach. The moving bed is assumed to be comprised of pellets of grains and crystallites. We also take into account eight heterogeneous and two homogeneous chemical reactions. The local mass, energy, and momentum balances are numerically solved, using the finite volume method. This model was successfully validated by simulating the shaft furnaces of two direct reduction plants of different capacities. The calculated results reveal the detailed interior behavior of the shaft furnace operation. Eight different zones can be distinguished, according to their predominant thermal and reaction characteristics. An important finding is the presence of a central zone of lesser temperature and conversion.

scholarly journals Hydrogen Ironmaking: How It Works

Metals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 922 ◽  
Author(s):  
Fabrice Patisson ◽  
Olivier Mirgaux
Keyword(s):  
Iron Ore ◽  
Shaft Furnace ◽  
Direct Reduction ◽  
Water Electrolysis ◽  
Current Standard ◽  
Ore Pellets ◽  
Production Of Hydrogen ◽  
Produce Steel ◽  
And Performance ◽  
Direct Reduction Of Iron

A new route for making steel from iron ore based on the use of hydrogen to reduce iron oxides is presented, detailed and analyzed. The main advantage of this steelmaking route is the dramatic reduction (90% off) in CO2 emissions compared to those of the current standard blast-furnace route. The first process of the route is the production of hydrogen by water electrolysis using CO2-lean electricity. The challenge is to achieve massive production of H2 in acceptable economic conditions. The second process is the direct reduction of iron ore in a shaft furnace operated with hydrogen only. The third process is the melting of the carbon-free direct reduced iron in an electric arc furnace to produce steel. From mathematical modeling of the direct reduction furnace, we show that complete metallization can be achieved in a reactor smaller than the current shaft furnaces that use syngas made from natural gas. The reduction processes at the scale of the ore pellets are described and modeled using a specific structural kinetic pellet model. Finally, the differences between the reduction by hydrogen and by carbon monoxide are discussed, from the grain scale to the reactor scale. Regarding the kinetics, reduction with hydrogen is definitely faster. Several research and development and innovation projects have very recently been launched that should confirm the viability and performance of this breakthrough and environmentally friendly ironmaking process.

scholarly journals Review and Thermodynamic Calculation of Gas-based Shaft Furnace Direct Reduction Ironmaking

2020 ◽  
Vol 218 ◽  
pp. 01032
Author(s):  
Weiming Luo
Keyword(s):  
Thermodynamic Calculation ◽  
Iron Ore ◽  
Shaft Furnace ◽  
Direct Reduction ◽  
Reduction Process ◽  
Reducing Agent ◽  
Reduction Degree

Different techniques have been used to study the reduction process of iron ore. In this paper, the reduction process of iron ore by CO at 200~1200°C is calculated. The effects of reducing agent overdose, reducing temperature and VCO2/(VCO+VCO2) on reducing degree were studied. The results show that the reduction degree increases with the increase of reducing agent and slows down gradually. During the reduction process, the reduction degree decreased significantly with the increase of VCO2/(VCO+VCO2). In this temperature segment, the reduction degree has a peak.

The sticking problem during direct reduction of fine iron ore in the fluidized bed

10.30544/378 ◽  
2004 ◽  
Vol 10 (4) ◽  
pp. 309-328 ◽  
Author(s):  
Mirko Komatina ◽  
HEINRICH W. GUDENAU
Keyword(s):  
Fluidized Bed ◽  
Iron Ore ◽  
Review Paper ◽  
Direct Reduction ◽  
Reduction Process ◽  
Experimental Investigations ◽  
Inert Material ◽  
Reduction Of Iron ◽  
Fine Iron ◽  
Direct Reduction Of Iron

In this review paper described are possible chemical reactions and their thermodynamic analysis during direct reduction. The sticking mechanism during direct reduction in the fluidized bed was analysed, and the reasons for the sticking appearance explained. The most important parameters on the sticking were analysed. The ways for prevention and observation were considered. The plan for experimental investigations was proposed. The investigations could be performed in fluidized bed reactor. Coal will be used as inert material. Separately, the influence volatile content in the coal on the reduction process and sticking appearance, will be analysed. As results of these investigations would be some improvements of the method direct reduction of iron ore in the fluidized bed.

Effects of reductant type on coal-based direct reduction of iron ore tailings

2018 ◽  
Vol 42 (3) ◽  
pp. 453-466
Author(s):  
Wei WANG ◽  
Pengfei YE ◽  
Xiaoli ZHOU ◽  
C WANG ◽  
Zekun HUO ◽  
...  
Keyword(s):  
Iron Ore ◽  
Direct Reduction ◽  
Iron Ore Tailings ◽  
Reduction Of Iron ◽  
Direct Reduction Of Iron

Separation of aluminium and preparation of powdered DRI from lateritic iron ore based on direct reduction process

2016 ◽  
Vol 55 (3) ◽  
pp. 345-355 ◽  
Author(s):  
T. Jiang ◽  
L. Yang ◽  
G. Li ◽  
J. Luo ◽  
J. Zeng ◽  
...  
Keyword(s):  
Iron Ore ◽  
Direct Reduction ◽  
Reduction Process ◽  
Direct Reduction Process

A simplified approach to the simulation of direct reduction of iron ore

2010 ◽  
Vol 107 (5) ◽  
pp. 195-204 ◽  
Author(s):  
M. Vannucci ◽  
V. Colla ◽  
G. Corbo ◽  
S. Fera
Keyword(s):  
Iron Ore ◽  
Direct Reduction ◽  
Simplified Approach ◽  
Reduction Of Iron ◽  
Direct Reduction Of Iron

scholarly journals Reduction Kinetics of Hematite Powder in Hydrogen Atmosphere at Moderate Temperatures

Metals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 751 ◽  
Author(s):  
Zhiyuan Chen ◽  
Jie Dang ◽  
Xiaojun Hu ◽  
Hongyan Yan
Keyword(s):  
Activation Energy ◽  
Direct Reduction ◽  
Reduction Process ◽  
Kinetic Mechanism ◽  
Hydrogen Atmosphere ◽  
Morphological Transformation ◽  
Iron And Steel ◽  
Multi Stage ◽  
Reduction Of Iron ◽  
Direct Reduction Of Iron

Hydrogen has received much attention in the development of direct reduction of iron ores because hydrogen metallurgy is one of the effective methods to reduce CO2 emission in the iron and steel industry. In this study, the kinetic mechanism of reduction of hematite particles was studied in a hydrogen atmosphere. The phases and morphological transformation of hematite during the reduction were characterized using X-ray diffraction and scanning electron microscopy with energy dispersive spectroscopy. It was found that porous magnetite was formed, and the particles were degraded during the reduction. Finally, sintering of the reduced iron and wüstite retarded the reductive progress. The average activation energy was extracted to be 86.1 kJ/mol and 79.1 kJ/mol according to Flynn-Wall-Ozawa (FWO) and Starink methods, respectively. The reaction fraction dependent values of activation energy were suggested to be the result of multi-stage reactions during the reduction process. Furthermore, the variation of activation energy value was smoothed after heat treatment of hematite particles.

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