The MIDREX® Process
In the early days of direct reduction, there was a clearly discernible difference between iron oxide pellets intended for blast furnace use (BF-grade pellets) and those used to make DRI to feed an EAF. A "DR-grade" pellet typically has higher iron content and less silica, alumina and other gangue constituents than "BF-grade" pellets.
Advanced physical model of hydrothermic reduction of iron ore pellets
In this model of a shaft furnace, a scientific approach is designed based on the dissociation of molecular-hydrogen gas (H 2 +) obtained by water electrolysis and ionisation of the hydrogen gas (2H+) and is incorporated for a high degree of gas adsorption and metallisation during chemical reduction of iron ore (Fe 2 O 3) pellets. The steps ...
Mathematical Model of the Shaft Furnace for Reduction of Iron-Ore Pellet
A mathematical model of the shaft furnace is developed for gaseous reduction of iron-ore pellet. In the model, the reduction of iron-oxide is defined as the multi-stage successive reaction and the reduction rate equations are derived from the multi-interface core model in a single pellet. This model is applied to the simulation for the changes ...
Behaviour of kaolinite coated olivine pellets in blast furnace
Abstract Production olivine fluxed blast furnace pellets were coated with a water based slurry of kaolinite to give a coating of 5 kg t-1 pellets. The LKAB experimental blast furnace in Lulea˚ was used to compare the behaviour of kaolinite coated olivine pellets (MPBO-KA) with that of regular olivine pellets coated with a water spray (MPBO …
Computational analysis of hydrogen reduction of iron oxide pellets …
The TGR H 2-SF considered in the current work is depicted schematically in Fig. 1.The unit is essentially a countercurrent heat exchanger and chemical reactor for converting the iron oxide pellets charged at the top to DRI of high metallization degree, with the reducing agent being pure H 2.To make use of the sensible heat carried by the …
Iron Ore Pelletizing Process: An Overview | IntechOpen
In 1943, E. W. Davies and co-workers demonstrated the process using an experimental shaft furnace. Commercial operation started in the 1950s in Sweden using vertical-shaft-kilns for firing the pellets. ... Souza R, Mendonca C, Kater T. Production of acid iron ore pellet for direct reduction using an organic binder. Mining Engineering. …
Global green hydrogen-based steel opportunities …
Whilst electric steelmaking furnaces can be readily decarbonised through renewable power, the most promising options to decarbonise ironmaking are: (i) green …
Iron ore pellet disintegration mechanism in simulated shaft …
The disintegration behavior and mechanism of iron ore pellet in simulated shaft furnace conditions were investigated in details. Effects of temperature, reducing …
Sticking behaviour and mechanism of iron ore pellets in …
In this study, the loading reduction experiments of iron ore pellets were carried out under the simulating COREX reducing conditions. The influence of temperature and H 2 content in the syngas on the sticking behaviour of the pellets was observed by scanning electron microscope, energy-dispersive spectrometer and X-ray diffraction. …
Sticking of iron ore pellets in direct reduction with …
A series of reduction experiments of iron ore pellets with hydrogen, carbon monoxide and their mixture were carried out in a laboratory scale shaft furnace. The sticking behavior accompanying reduction of iron ore pellets was investigated. And morphology of the sticking interface forming during reduction was analyzed by SEM …
Analysis of impact of mechanical degradation of iron ore pellets …
The use of iron ore pellets instead of lump ores has increased in recent years due to the decrease in the availability and quality of lump iron ores and more rigorous environmental constrains applied to the sintering processes. Indeed, the iron ore pellet market is expected to grow at a rate of 5 % during forecast period in the present decade ...
Investigation of Pellet Shape on the Hydrogen Reduction of Iron …
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 ...
Sticking behaviour and mechanism of iron ore pellets in …
Sticking behaviour and mechanism of iron ore pellets in COREX pre-reduction shaft furnace. Zhan-xia Di, Zheng-yi Li, Ru-fei Wei, Ying Liu, Qing-min Meng, Tie-jun Chun, …
Effect of Coatings and Coating Methods on Cluster Index in Iron …
A series of reduction experiments of iron ore pellets with hydrogen, carbon monoxide and their mixture were carried out in a laboratory scale shaft furnace. The sticking behavior accompanying ...
Numerical investigation of nonisothermal reduction of
Abstract. A mathematical model is developed to investigate the reduction process of hematite in the reduction zone of the Midrex shaft furnace as a moving bed …
Iron ore pellet disintegration mechanism in simulated shaft …
Disintegration of iron ore pellet in simulated shaft furnace conditions was studied. • Pellet disintegrated acutely as reduced by H 2 /CO = 0.8 at 550 °C. • Lattice …
Reduction characteristics of cold-agglomerated pellets in blast furnace
There is a significant and necessary drive towards reducing CO 2 emissions produced by iron and steelmaking industries. Binding Solutions Ltd has developed a technology to contribute to the reduction of CO 2 in the short and long term, by introducing a cold-bonded iron ore pellet to the furnace burden. Binding Solutions' cold …
Effect of titanium on the sticking of pellets based on …
Direct reduction based on hydrogen metallurgical gas-based shaft furnace is a promising technology for the efficient and low-carbon smelting of vanadium–titanium magnetite. However, in this process, the sticking of pellets occurs due to the aggregation of metallic iron between the contact surfaces of adjacent pellets and has a serious …
Detailed Modeling of the Direct Reduction of Iron Ore in a Shaft Furnace
This paper addresses the modeling of the iron ore direct reduction process, a process likely to reduce CO 2 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 …
Reduction of Iron Ore Pellets, Sinter, and Lump Ore under …
It is found that lump ore has lowest reduction rate in all test conditions, and at lower temperatures iron ore pellets reduce faster than sinter, and this is reversed at …
A numerical study on process intensification of hydrogen …
In this paper, techno-economically feasible technologies for improving the performance of a shaft furnace for hydrogen reduction of iron oxide pellets are explored using a simplified algebraic model in combination with a computational fluid dynamics -based shaft furnace model. The former determines the theoretical maximum gas utilization degree that …
Shaft Furnace
The MIDREX® shaft furnace is designed to operate with a combination of pellets and lump ores virtually in any proportion. This allows the plant operator to maximize productivity at the lowest cost. MIDREX® plants are reported to have processed iron oxide pellets and lump ores from over 50 sources around the world.
Iron ore pelletization
Iron ore pellets are essential burden materials to improve the performance of modern blast furnaces, because they possess high iron grade, low silica and alumina contents, excellent mechanical strength and metallurgical performance with a uniform size distribution. ... Iran: 5.200: 6.200: 7.200: Khouzestan: Iran: 4.430: 4.920: 5.040: Go …
Iron ore pellet disintegration mechanism in simulated shaft furnace
The disintegration behavior and mechanism of iron ore pellet in simulated shaft furnace conditions were investigated in details. Effects of temperature, reducing gas and gangue compositions were emphatically discussed. It was found that pellet disintegrated acutely as reduced by H 2 /CO = 0.8 at 550 °C. Gangue minerals in pellet …
Sticking behaviour and mechanism of iron ore pellets in …
Methods A numerical model for an 8m2 pellet shaft furnace has been developed on the basis of reaction engineering by taking into account gas flow, heat exchange between pellets and gas, and ...
MODELING THE IRON ORE PELLETS REDUCTION ON SHAFT FURNACE PROCESS
In this work, a. comprehensive mat hematical model for the direct reduction of iron oxides in the shaft furnace has been developed and. used to simulate the steady state of commercial shaft ...
Global green hydrogen-based steel opportunities …
The shaft furnace operates using a counterflowing ore and reducing gas to produce a sponge iron product, requiring ore in pellet form with minimum 67% Fe content 21 to limit ore impurities and ...
Swelling behavior of iron ore pellet reduced by H2–CO …
1. Introduction. Volume swelling of iron ore pellets accompanied with strength decrease appears commonly during reduction. In order to ensure permeability and operation in shaft furnace smelting processes, the maximum swelling index of pellet is always required to be no more than 20% [1], [2].Numerous researches have been done …
Sticking behaviour and mechanism of iron ore pellets in …
(DOI: 10.1080/03019233.2017.1361079) COREX is a clean process releasing lower pollution and consuming fewer cokes than the blast furnace process. However, serious sticking phenomenon often occurs in COREX shaft furnace, causing many problems to the normal operation. In this study, the loading reduction experiments of …
Influence of Operation Parameters on Sticking Behavior of Pellets …
The sticking behavior of iron ores in the shaft furnace is one of the most important problems in the COREX melting progress, which directly influence the smooth operation and productivity of shaft furnace. ... L. Y. Yi, et al, "Sticking of Iron Ore Pellets in Direct Reduction with Hydrogen and Carbon Monoxide: Behavior and Prevention".