scholarly journals Influence of Parameters on the Pre-Reduction Process of Vanadium-Titanium Magnetite Carbon-Containing Composite Pellets in Rotary Kiln

Metals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 45
Author(s):  
Bo Wang ◽  
Xueyong Ding ◽  
Tianhua Ju ◽  
Xiaofei Zhang ◽  
Gongjin Cheng
Keyword(s):  
Rotary Kiln ◽  
Reduction Process ◽  
Holding Time ◽  
Reduction Temperature ◽  
Smelting Reduction ◽  
Total Oxygen ◽  
Metallization Rate ◽  
Composite Pellets ◽  
Melting Pool ◽  
Titanium Magnetite

A novel smelting reduction process called pre-reduction in rotary kiln and total oxygen melting pool is a promising route to reduce environmental pollution from the ironmaking industry. In this paper, the process parameters and appropriate efficiency of reduction in the pre-reduction process of the rotary kiln were investigated via the detection of the metallization rate, phase composition, and internal morphology of the product combining with the analysis of the off-gas. The results indicated that the parameters of reduction temperature, reduction holding time, and coal ratio have a remarkable influence on the metallization rate. The reduction temperature has the most significant effect, followed by the reduction time and the coal ratio. Furthermore, under the condition of reduction temperature 1000 °C, holding time 30 min, coal ratio = 1, a product with a metallization rate of more than 70% can be obtained, which meets the requirements of the rotary kiln process, and its CO2/CO value of the pre-reduction endpoint is appropriate. Continue to increase the temperature, holding time, and coal ratio can raise the metallization rate of the pellets, but only a little improvement and may cause reoxidation of the product.

scholarly journals Effect of catalyst on tail gas during reduction of vanadium-titanium magnetite carbon-containing pellet

2021 ◽  
Vol 267 ◽  
pp. 02046
Author(s):  
Bo Wang ◽  
Xueyong Ding ◽  
Xiaofei Zhang ◽  
Tianhua Ju ◽  
Shigang Li
Keyword(s):  
Rotary Kiln ◽  
Flue Gas ◽  
Reduction Process ◽  
Reduction Mechanism ◽  
Gas Analyzer ◽  
Metallization Rate ◽  
Vanadium Titanium ◽  
Reduction Effect ◽  
Calcium Catalysts ◽  
Titanium Magnetite

Catalyst can enhance the reduction effect and promote the reduction of vanadium titanomagnetite. In this paper, the carbon-containing pellets of vanadium titanomagnetite were prepared by using highly volatile coal as the reducing agent under the background of a novel process of pre-reduction in the rotary kiln. The effects of CaO, CaCO3, B2O3 and borax (Na2B4O7·10H2O) on the tail gas characteristics of carbon-containing pellets in the prereduction process were studied by using a simulated rotary kiln and flue gas analyzer. The results showed that the enhanced reduction effect of boron catalysts was slightly stronger than that of calcium catalysts, among which CaO catalyzed the least and borax the best. With the increase of metallization rate, the CO utilization in the tail gas is generally reduced, while when using CaCO3 as the catalyst, the CO utilization is significantly increased. Due to different reduction mechanism, the boron catalysts have little effect on the tail gas, and the calcium catalysts have a great effect on the tail gas. Based on the experimental results and the characteristics of the tail gas from the reduction process, we put forward the idea of using CaCO3 as the best catalyst and using CaO to absorb CO2 in the tail gas to form CaCO3.

scholarly journals The effect of composite reducing agent on the reduction process and the tail gas of carbon-containing pellets

2021 ◽  
Vol 267 ◽  
pp. 02040
Author(s):  
Bo Wang ◽  
Xueyong Ding ◽  
Xiaofei Zhang ◽  
Tianhua Ju ◽  
Shigang Li
Keyword(s):  
Rotary Kiln ◽  
Bituminous Coal ◽  
Reduction Process ◽  
Reducing Agent ◽  
Process Conditions ◽  
Metallization Rate ◽  
New Type ◽  
Vanadium Titanium ◽  
Ironmaking Process ◽  
Titanium Magnetite

In order to explore a reasonable way for the efficient utilization of coal resources in the ironmaking process. In this paper, lignite and bituminous coal are used as reducing agents, and two types of vanadium-titanium magnetite composite reducing agent pellets are prepared for different content ratios and mixed forms of the two coal powders. Under the simulated rotary kiln pre-reduction conditions, the influence of the ratio and mixing of pulverized coal on the metallization rate and tail gas composition of the reduction process was explored. The results show that increasing the proportion of high volatile lignite is beneficial to the reduction of pellets and can obtain pellets with a higher metallization rate. Under the new pre-reduction process conditions of the rotary kiln, the vanadium-titanium magnetite double-layer pellet with 75wt% lignite inside and 25wt% bituminous coal outside has the highest metallization rate of about 76%. At the same time, this new type of composite reducing agent pellets reduced gas emissions. This pellet is of great significance to the coal-based ironmaking process.

scholarly journals Recovery of Iron, Chromium, and Nickel from Pickling Sludge Using Smelting Reduction

Metals ◽  
2018 ◽  
Vol 8 (11) ◽  
pp. 936 ◽  
Author(s):  
Zhaohui Tang ◽  
Xueyong Ding ◽  
Xinlin Yan ◽  
Yue Dong ◽  
Chenghong Liu
Keyword(s):  
Reduction Process ◽  
Slag Basicity ◽  
Experimental Results ◽  
Iron Ores ◽  
Reduction Temperature ◽  
Smelting Reduction ◽  
Reduction Time ◽  
Temperature Reduction ◽  
Pickling Sludge ◽  
Iron Chromium

This paper reports the recoveries of iron, chromium, and nickel from pickling sludge using coal-based smelting reduction. The influences of slag basicity (CaO/SiO2, which is controlled by high phosphorus oolitic hematite iron ores), reduction temperature, reduction time, and the C/O mole ratio on the recoveries of Fe, Cr, and Ni are investigated systematically. The experimental results show that high recoveries of Fe (98.91%), Cr (98.46%), and Ni (99.44%) are produced from pickling sludge with optimized parameters for the smelting reduction process. The optimized parameters are a slag basicity of 1.5; a reduction temperature of 1550 °C, a reduction time of 90 min, and a C/O mole ratio of 2.0. These parameters can be used as technical support for the recycling of pickling sludge with pyrometallurgy.

Study on Utilization Technology of Vanadium Titanium Magnetite Based on the Rotary Hearth Furnace Direct Reduction Process

2012 ◽  
Vol 217-219 ◽  
pp. 441-444 ◽  
Author(s):  
Gong Guo Liu
Keyword(s):  
Recovery Rate ◽  
Large Scale ◽  
Direct Reduction ◽  
Reduction Rate ◽  
Reduction Process ◽  
Direct Reduction Process ◽  
Metallization Rate ◽  
Study Results ◽  
Vanadium Titanium ◽  
Titanium Magnetite

Through carrying out large scale of experiments, the process of ‘rotary harth furnace direct reduction—deep reduction electric arc furnace—extracting vanadium from vanadium bearing slag—extracting titanium from titanium bearing slag gets through and the recovery of Fe, V and Ti reached 90.77%, 43.82% and 72.65% respectively. With the study on the laboratory experiments and industrial tests, the bottlenecks of this technology such as low metallization rate of vanadium-titanium magnetite in direct reduction process, low reduction rate of vanadium in EAF, vanadium-recovery of hot metal with high silicon content, titanium-recovery of high –Mg &Al slag with titanium, and so on, have been solved. Based on this, the metallization rate of vanadium-titanium magnetite in direct reduction process is more than 90%, reduction rate of vanadium in EAF deep reduction process is more than 80%, vanadium-recovery rate in slag is more than 65%, and titanium-recovery rate in slag is more than 75%. That means good study results have been gotten. Furthermore, low-carbon pig iron with good quality in EAF steelmaking are gotten. Otherwise, V2O5 sheet and titanium products can meet the requirements of GB3283-87 and PTA121, respectively.

Research on Direct Reduction Dynamic Model of Carbon-Bearing Pellet Containing Zinc

2011 ◽  
Vol 214 ◽  
pp. 369-373
Author(s):  
Jing Song Wang ◽  
Xiu Wei An ◽  
Wan Hua Yu ◽  
Xue Feng She ◽  
Yin Gui Ding ◽  
...  
Keyword(s):  
Heat Transfer ◽  
Experimental Data ◽  
Mathematical Model ◽  
Direct Reduction ◽  
Reduction Process ◽  
Reduction Temperature ◽  
Coupled Heat Transfer ◽  
Reducing Gas ◽  
Metallization Rate ◽  
Process Factors

Base on reduction experimental data, considering the reduction process factors like carbon content, reductive removal of ZnO, changing size of pellet, and partial pressure of reducing gas, also coupled heat transfer, mass transfer and chemical reactions, a direct reduction mathematical model on carbon-bearing pellet containing zinc has been established. The reliability of the model was testified by programming and experiments. Experiments showed that, under the reduction conditions that carbon and oxygen mole ratio at 1.0 and reduction temperature 1603K, metallization rate 87% and dezincification rate 99% were observed after 15 minutes of heating.

scholarly journals Selective Reduction of High Alumina-Lateritic Nickel Ore (0.5 Ni-44Fe-16Al2O3)

2019 ◽  
Vol 14 (2) ◽  
pp. 130-138
Author(s):  
Fajar Nurjaman ◽  
Wahyuningsih Wahyuningsih ◽  
Pulung Karo Karo ◽  
Ediman Ginting ◽  
Achmad Shofi ◽  
...  
Keyword(s):  
Selective Reduction ◽  
Reduction Process ◽  
Holding Time ◽  
High Alumina ◽  
Reduction Temperature ◽  
X Ray Diffraction ◽  
Optimal Process ◽  
X Ray ◽  
Lateritic Nickel ◽  
Iron Grade

In this present study, the effect of reductant dosage, temperature and holding time on selective reduction process of high alumina-lateritic nickel ore have been investigated clearly. The lateritic nickel ore was reduced with 5 until 15 wt. % anthracite and 10 wt. % sodium sulfate at reduction temperature of 950ºC, 1050ºC and 1150°C for 60, 90, and 120 minutes. Magnetic separation process was then conducted to separate the concentrate and tailing. The analysis of reduced nickel ore is performed by the Atomic Absorption Spectroscopy, X-Ray Diffraction, and Secondary Electron Microscopy. The optimal process resulted from the reduction of nickel ore with 10 wt. % anthracite at the temperature of 1050°C for 120 minutes which resulted in 0.84% nickel in concentrate. The troilite was not found in reduced ore. The iron grade increased along the increased of reduction temperature. The longer of holding time in selective reduction process increased the nickel grade but it decreased the iron grade.

scholarly journals Impact of Iron on the Fe–Co–Ni Ternary Nanocomposites Structural and Magnetic Features Obtained via Chemical Precipitation Followed by Reduction Process for Various Magnetically Coupled Devices Applications

Nanomaterials ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 341
Author(s):  
Tien Hiep Nguyen ◽  
Gopalu Karunakaran ◽  
Yu.V. Konyukhov ◽  
Nguyen Van Minh ◽  
D.Yu. Karpenkov ◽  
...  
Keyword(s):  
Particle Size ◽  
Magnetic Properties ◽  
Reduction Process ◽  
Chemical Precipitation ◽  
Precipitation Method ◽  
Magnetic Characteristics ◽  
Reduction Temperature ◽  
Fe Content ◽  
Magnetic Features ◽  
Co Precipitation

This paper presents the synthesis of Fe–Co–Ni nanocomposites by chemical precipitation, followed by a reduction process. It was found that the influence of the chemical composition and reduction temperature greatly alters the phase formation, its structures, particle size distribution, and magnetic properties of Fe–Co–Ni nanocomposites. The initial hydroxides of Fe–Co–Ni combinations were prepared by the co-precipitation method from nitrate precursors and precipitated using alkali. The reduction process was carried out by hydrogen in the temperature range of 300–500 °C under isothermal conditions. The nanocomposites had metallic and intermetallic phases with different lattice parameter values due to the increase in Fe content. In this paper, we showed that the values of the magnetic parameters of nanocomposites can be controlled in the ranges of MS = 7.6–192.5 Am2/kg, Mr = 0.4–39.7 Am2/kg, Mr/Ms = 0.02–0.32, and HcM = 4.72–60.68 kA/m by regulating the composition and reduction temperature of the Fe–Co–Ni composites. Due to the reduction process, drastic variations in the magnetic features result from the intermetallic and metallic face formation. The variation in magnetic characteristics is guided by the reduction degree, particle size growth, and crystallinity enhancement. Moreover, the reduction of the surface spins fraction of the nanocomposites under their growth induced an increase in the saturation magnetization. This is the first report where the influence of Fe content on the Fe–Co–Ni ternary system phase content and magnetic properties was evaluated. The Fe–Co–Ni ternary nanocomposites obtained by co-precipitation, followed by the hydrogen reduction led to the formation of better magnetic materials for various magnetically coupled device applications.

Solid Flow in a Shaft Furnace in Smelting Reduction Process under Circumferential Imbalance Conditions

2017 ◽  
Vol 88 (12) ◽  
pp. 1700212 ◽  
Author(s):  
Heng Zhou ◽  
Shengli Wu ◽  
Mingyin Kou ◽  
Biao Tang ◽  
Hanchi Cheng ◽  
...  
Keyword(s):  
Shaft Furnace ◽  
Reduction Process ◽  
Smelting Reduction ◽  
Solid Flow

Impact of slag composition activity on the behavior of phosphorus in the smelting reduction process of high-phosphorus iron ores

2017 ◽  
Vol 42 (38) ◽  
pp. 24487-24494 ◽  
Author(s):  
Yiqin Liu ◽  
Hao Zhang ◽  
Zengen Li ◽  
Aimin Zhang ◽  
Xiaohui Zhang ◽  
...  
Keyword(s):  
Slag Composition ◽  
Reduction Process ◽  
Iron Ores ◽  
Smelting Reduction ◽  
High Phosphorus ◽  
Phosphorus Iron
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