Semantic Scholar extracted view of "Reducing gas composition optimization for COREX® pre-reduction shaft furnace based on CO-H2 mixture" by Xinying Guo et al.
The MIDREX® Process is unsurpassed in the Direct Reduction industry in terms of production and process flexibility to meet the constantly evolving nature of steelmakers and ore-based metallics providers. Adjustable product quality and the flexibility to produce various forms of iron together with some of the best production records industry ...
A techno-economic approach for magnetising roasting of iron ore composite pellet using conventional and hybrid microwave furnace
This study investigated the oxidation induration of Hongge vanadium titanomagnetite pellets (HVTMP) with different TiO 2 additions, and its influence on subsequent reduction behavior with simulated shaft furnace gases.
Hydrogen-based shaft furnace process is gaining more and more attention due to its low carbon emission, and the reduction behavior of iron bearing burdens …
Semantic Scholar extracted view of "Improving hydrogen-rich gas-based shaft furnace direct reduction of fired hematite pellets by modifying basicity" by Yue Shi et al.
The reduction and melting behavior of carbon composite iron ore hot briquette in shaft furnace are discussed. As these agglomerates are made by the use of thermal plasticity of coal, the reduction ...
In a shaft furnace, the reducing gases injected into the middle and the bottom part of the shaft are gradually diluted by the spent gases emitted from the …
For direct reduction processes that switch dy- namically between reformed natural gas and hydrogen as the reductant, it is important to under- stand the effects of the transition on …
The second is that the time to reduction of high-quality pellets tends to be reduced, so leading to an increase in the shaft furnaces productivity and to the reduction of energy consumption.
addition, reduction tem- perature, reduction time, and load are very important to the sticking behavior of pellets during the direct reduction under hydrogen. In the process of direct …
Sticking of pellets occurs in the direct reduction process of gas-based shaft furnace. This phenomenon has negative effects on the smooth flow of raw materials and continuous operation of production,…
The influence of basicity on the metallurgical performances and reduction characteristics of fired super high-grade magnetite pellets under the simulated shaft furnace gas conditions was…
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.
The investigations on direct reduced iron (DRI) have commonly been made at two different scales: the pellet scale and the macroscopic or reactor scale. The reduction of a single pellet is typically investigated for developing kinetics of chemical reactions accompanied by heat and mass transport, whereas in the macroscopic view, …
Through the preparation of titanium concentrate oxidized pellets, gas-based shaft furnace reduction experiments, and melting and separation experiments, the phase changes during the roasting ...
The term composite pellet is being employed here to mean a pellet containing mixture of fines of iron-bearing oxides and carbonaceous material (coal/coke/char), bonded essentially at room …
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 reactor. It is described as a counter-current moving bed cylindrical reactor in which hematite pellets are reduced by a gaseous mixture of hydrogen, water vapour, carbon dioxide and carbon …
The reduction and melting behavior of carbon composite iron ore hot briquette in shaft furnace are discussed. As these agglomerates are made by the use of thermal plasticity of coal, the reduction…
As part of efforts to reduce anthropogenic CO2 emissions by the steelmaking industry, this study investigated the direct reduction of industrially produced hematite pellets with H2 using the Doehlert experimental design to evaluate the effect of pellet diameter (10.5–16.5 mm), porosity (0.36–0.44), and temperature (600–1200°C). A …
General pellet chemistry – The type and percentages of chemical elements will determine the tendency of pellets to stick and form clusters in the shaft furnace.
Synopsis: 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 of …
Second, an increase in H 2 concentration helped prevent the pellets from sticking inside the shaft furnace, which could be quantified by the specific index [79].
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 ...
Sticking of pellets occurs in the direct reduction process of gas-based shaft furnace. This phenomenon has negative effects on the smooth flow of raw materials and …
By means of in-situ observation, this study investigates the direct reduction (DR) of individual iron ore pellets under an atmosphere of hydrogen (H 2) and carbon …
From the perspective of reduction swelling, all pellets show a tendency to shrink without catastrophic expansion and are able to meet the actual production requirements. The …
Gas-based direct reduction in a shaft furnace is the dominant process in the world for production of direct reduced iron. As fresh reducing gas passes through the iron ore burden, it is diluted by the gas emitted from the reacted iron ores which decreases the reduction potential of the reducing gas.
Currently, two feasible smelting solutions that can replace traditional blast furnace smelting are blast furnace with hydrogen injection and direct reduced iron …
In this paper, a numerical model based on transport equations of momentum, energy and chemical species for gas and solid phases is proposed to simulate the inner phenomena in the direct …
Sticking of pellets occurs in the direct reduction process of gas-based shaft furnace. This phenomenon has negative effects on the smooth flow of raw materials and continuous operation of ...
Sticking of pellets occurs in the direct reduction process of gas-based shaft furnace. This phenomenon has negative effects on the smooth flow of raw materials and continuous operation of production, leading to lower product quality and productivity. The objective of this study is to determine the optimal process conditions for direct reduction …
It is a two-step process in which the ore is partially reduced at the first stage in a shaft furnace and the remaining reduction is achieved at the second stage in a melter gasifier.
To provide theoretical basis and technical support for the effective utilization of ultra-high grade pellets in hydrogen-based shaft furnace, the reduction swelling behavior of ultra-high grade iron pellets with various SiO 2 and Al 2 O 3 was studied in present work and the following conclusions can be obtained.
Sticking of iron ore-coal composite pellets reduction may attribute to the intergrowth of metallic iron or ferrous oxide crystals between boundaries, and high melting point substances formed by MgO and FexOy can effectively prevent such intergrowth [7].
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 …
A series of reduction experiments of iron ore composite pellets with different carbona- ceous materials was performed under isothermal conditions to investigate the reduction behaviors of the carbon iron ore composite pellets.
Detailed information about the interaction between direct reduction gases and BF grade and DR grade pellets and sinter under conditions which are directly relevant for the hydrogen-dominated DRI shaft furnace;
