Effect of adding limestone on the metallurgical properties of iron ore …
A higher reducibility indicates more indirect reduction in the blast furnace, resulting in a lower coke rate and higher productivity. The reducibility test in CO–CO 2 –N 2 gas showed that limestone enhances the reduction reactions in the acid iron ore pellets. One reason for this is the higher porosity of the fluxed pellets compared to the ...
Optimization of the Iron Ore Direct Reduction Process …
The reduction of the iron ore pellets is described using a specific grain model, reflecting the transformations from hematite to iron. The shaft furnace is modeled as a set of interconnected one-dimensional zones into which the principal chemical reactions (3-step reduction, methane reforming, Boudouard and water gas shift) are …
Direct reduction of iron ore pellets by H2-CO mixture: An in …
The iron and steel metallurgy industry faces the question of how to replace carbon in iron ore reduction to reduce CO 2 emission in basic industries and achieve the expectation of "double carbon". This study investigates the reduction swelling of individual iron ore pellet under mixed H 2-CO atmospheres and at temperatures of 800–1000 ℃ …
Hydrogen direct reduction ironmaking process for zero
The TGA consists of a furnace containing a single pellet sample supported by an alumina plate crucible. A precision balance (0.001 g) measures the mass of the pellet throughout the reaction time. ... Mathematical modeling of the reaction in an iron ore pellet using a mixture of hydrogen, water vapor, carbon monoxide and carbon dioxide: …
(PDF) Decarbonization of the Iron and Steel Industry with …
The DRI shaft furnace is a counter-current solid-gas reactor, where pre-heated iron ore pellets at 800 C are fed from the top to react with hydr ogen stream entering from the bottom of the reactor .
Multiscale modeling of non-catalytic gas-solid reactions …
Incorporating the shift reaction improved the model's agreement with data obtained from a pilot plant scale reactor. Alamsari et al. [25] expanded the scope of reactions involved by incorporating the steam reforming reaction into the reduction of iron ore pellets and simulating the shaft furnace cooling zone. Their model also considered …
[PDF] Reduction of Iron Ore Pellets, Sinter, and Lump Ore …
A blast furnace (BF) is the dominant process for making iron in the world. The BF is charged with metallurgical coke and iron burden materials including iron ore pellets, sinter, and lump ore. While descending in the BF the charge materials reduce. The iron‐bearing materials should reduce fast and remain in the solid form until as high a …
Detailed Modeling of the Direct Reduction of Iron Ore in a Shaft Furnace
Numerous iron ore shaf t furnace models were thus proposed in the literature. The first 50 studies addressed the reduction of a single pellet by H 2, CO, or H 2 -CO mixtures [5-10].
Results of Hydrogen Reduction of Iron Ore Pellets at …
The application of hydrogen as a reducing agent in existing blast furnaces presents a promising avenue for significantly reducing emissions. The current emphasis on hydrogen reduction may necessitate a review of parameters such as the temperature, chemical composition, porosity, reduction time, and reducing agent. In this study, the …
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 …
Three-dimensional characterization of porosity in iron ore pellets…
This paper presents a comprehensive study on the production and reduction of high-quality iron ore pellets characterized by a basicity index nearing 0.5 and diameters ranging from 1 to 2 cm. The reduction process was carried out in a hydrogen atmosphere at temperatures spanning 800–1000 °C and a pressure of 8 bar.
Sticking behaviour and mechanism of iron ore pellets in …
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 iron ore pellets were carried out under the simulating …
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 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 …
Sticking behaviour and mechanism of iron ore pellets in …
Their particle size is. 10 –16 mm. Chemical composition of the pellets is shown in Table 1. According to the actual COREX furnace gas, the reducing gas flow is set as 0.88 m3h−1, and its ...
MODELING THE IRON ORE PELLETS REDUCTION ON …
The shaft reduction process involves complex phenomena of momentum, energy and mass transfer. Usually, the direct reduction of shaft furnace is divided into 3 zones. The reduction, transition and ...
Direct reduction of iron ore/biomass composite pellets …
As the iron reduction using either conventional blast furnace or new emerging direct reduction technology is driven by carbothermic Boudouard reaction, ... Such result indicated that biomass can reduce the reaction activation energy and improve the reaction rate reduction of iron ore pellets. It was perorated above that the kinetic of …
Kinetics of Reduction in Stages of Pellets Prepared from the …
To explore the reduction swelling process of pellets prepared from the Bayan Obo iron ore concentrate, based on the iron oxide reduction theory of pellets, the reduction of pellets prepared from the Bayan Obo iron ore concentrate was analyzed by thermogravimetric experiments and kinetic calculations in three stages. The reason for …
CO2 Emission Reduction in Blast Furnaces | SpringerLink
Once these materials are charged into the furnace top, they go through numerous chemical and physical reactions while descending to the bottom of the furnace. The iron ore, pellets, and sinter are reduced, simply meaning that the oxygen in the iron oxides is removed by a series of chemical reactions . These reactions occur as follows …
Reduction of Iron Ore Pellets, Sinter, and Lump Ore …
Herein, the reducibility of the iron ore pellet, sinter, and lump ore in the BF shaft are focused on. The experiments are conducted isothermally with a blast furnace simulator (BFS) high-temperature furnace at four different temperatures (700, 800, 900, and 1000 C) for 300 min. The experimental atmosphere consists of CO, CO2, H2, H2O, …
Modeling of iron ore reactions in blast furnace
Iron ore (pellet, sinter and lump ore) is gradually reduced to iron in blast furnace. The reductions are a serial of heterogeneous gas solid reactions that take place from the top of the furnace and throughout the shaft region of the furnace. Two major categories of iron ore reaction model had been developed and applied for modeling the iron ore …
HYL Process for Direct Reduction of Iron Ore – IspatGuru
Energiron direct reduction process (HYL process) uses a shaft reduction furnace to produce DRI. It is designed to convert iron pellet/lump ore into metallic iron by the use of reducing gases in a solid-gas moving bed shaft furnace. O2 is removed from the iron ore by chemical reactions based on H2 and CO, for the production of highly …
Detailed Modeling of the Direct Reduction of Iron Ore in …
composed of spherical iron ore pellets that descend by gravity. The pellet diameter (dp) is assumed to be unique and unchanging during the reduction reaction, and the initial pellet composition is known. The gas phase is composed of six species: H2, CO, H2O, CO2, N2, and CH4. The reducing gas is injected from the sidewall, at a height of z = H
Effect of Adding Limestone on the Metallurgical Properties of Iron Ore
Iron ore pellets are small and hard spherical particles agglomerated from a fine iron ore concentrate. They are used in the blast furnace process to produce hot metal. The diameter of blast ...
Reduction of low grade iron ore pellet using palm kernel shell
Palm kernel shell (PKS) waste serves as energy and source of CO and H 2 for iron ore reduction process. PKS content and reduction temperature significantly influenced the reduction rate of PKS–iron ore composite pellet. Iron oxide in iron ore–30 mass% PKS composite pellet can be transformed into magnetite and partially to wustite at 900 °C.
Degradation mechanism of high alumina refractory bricks by reaction …
Iron ore pellet is one of the critical burdens for the blast furnace process [1,2]. Owing to the increasing steel demand, iron ore pellets production has significantly expanded in recent years [3,4]. There are three main processes to produce iron ore pellets, including the grate-kiln process, the shaft furnace process, and the straight …
Effect of Blaine Fineness on the Quality of Hematite Iron Ore Pellets
Iron ore is the main raw material in blast furnaces for ironmaking. Iron ore particles are usually pelletized and sintered to be the feed in blast furnaces (Bolen, 2014;Graça et al., 2015 ...
Study of the induration phenomena in single pellet to …
The mass transfer takes place in the pelletizing furnace due to chemical reactions and phase transformations. Firstly the moisture is evaporated from the interior of solids where the vapor water diffusion through boundary layer plays important role. ... Virtual indurator: a tool for simulation of induration of wet iron ore pellets on a moving ...
Optimization of the Iron Ore Direct Reduction Process …
The reduction of the iron ore pellets is described using a specific grain model, reflecting the transformations from hematite to iron. The shaft furnace is modeled as a set of interconnected one-dimensional zones into which the principal chemical reactions (3-step reduction, methane reforming, Boudouard and water gas shift) are accounted for
Direct Reduced Iron and its Production Processes – …
Feed material for the DR process is either sized iron ore of size ranging from 10 mm to 30 mm or iron ore pellets of size ranging from 8 mm to 20 mm produced in an iron ore pellet plant. The gas based process uses a shaft furnace for the reduction reaction. The coal based process uses any one of the four types of reactors for the …
Iron Ore Pellet
1.2.2.2 Agglomeration of Iron Ore. The three major forms of iron used in ironmaking are pellets, lump, and sinter. The major change in the past 50 years has been the development of cost-effective pelletization technology allowing pellets to be a major source of iron oxide for ironmaking processes. From 1965 to 1985, the percentage of iron feed ...