scholarly journals The Mechanism of the Effect of Al2O3 Content on the Liquid Phase Fluidity of Iron Ore Fines

Processes ◽  
2019 ◽  
Vol 7 (12) ◽  
pp. 931 ◽  
Author(s):  
Heping Li ◽  
Shengli Wu ◽  
Zhibin Hong ◽  
Weili Zhang ◽  
Heng Zhou ◽  
...  
Keyword(s):  
Liquid Phase ◽  
Mineral Composition ◽  
Phase Formation ◽  
Iron Ore ◽  
Al2o3 Content ◽  
Calcium Ferrite ◽  
Sintering Process ◽  
Liquidity Index ◽  
Iron Ore Fines

The sintering process is significantly important for the ironmaking in China because of the large amount of sinter consumed. Al2O3 is an important element determining the quality and quantity of sinter. However, different conclusions have been made regarding the effects of Al2O3 on the amount and fluidity of the liquid phase formed in the sinter phase. Therefore, it is necessary to examine the effects of Al2O3 content on the amount and fluidity of the liquid phase. The present work investigated the effects of different Al2O3 contents of iron ore fines on the liquid phase formation, mineral composition, and consolidation strength. The results showed that a small amount of Al2O3 increased the amount of calcium ferrite, making the liquid phase formation easier. As the Al2O3 content in iron ore fines increased, the liquidity index decreased continuously, while the fluidity and the consolidation strength of the sintered body were directly related to the content squared. The quality of the sinter is optimal when the Al2O3 content of the iron ore fines is about 2 wt % (the SiO2 content is 4 wt %).

Effects of Compound Silicate Gangue on Mineral Composition and Microstructure of Sinter Produced by Baiyunebo Iron Ore Concentrates

2011 ◽  
Vol 194-196 ◽  
pp. 201-206
Author(s):  
Guo Ping Luo ◽  
Sheng Li Wu ◽  
Yi Ci Wang ◽  
Guang Jie Zhang ◽  
Zhi Zhong Hao ◽  
...  
Keyword(s):  
Mineral Composition ◽  
Iron Ore ◽  
Glassy Phase ◽  
Optical Microscope ◽  
Calcium Ferrite ◽  
Melting Time ◽  
Sintering Process ◽  
Test Device ◽  
Lower Melting Point ◽  
Mineral Compositions

The effects of compound silicate gangue on mineral composition and microstructure of sinter produced by Baiyunebo iron ore concentrates was studied by using mini-sintering test device and optical microscope. The result showed that compound silicate gangue has lower melting point, wider melting temperature range, longer melting time and melts easily to form glassiness during the sintering process. It can promote the solution of CaO and CaF2 in glassy phase, which affects viscosity and fluidity of glassy phase as well as the homogeneity of sinter microstructure. The compound silicate gangue intensely inhibits the generation of complex calcium ferrite and cuspidine as well. The major mineral compositions of sinter are hematite and glassy phase. The sinter exhibits multi-cavities and grainy structure when SiO2 exists entirely in the form of compound silicate gangue.

scholarly journals Effect of Thermodynamic Melt Formation Characteristics on Liquid Phase Fluidity of Iron Ore in the Sintering Process

Metals ◽  
2019 ◽  
Vol 9 (4) ◽  
pp. 404 ◽  
Author(s):  
Shengli Wu ◽  
Heping Li ◽  
Weili Zhang ◽  
Bo Su
Keyword(s):  
Liquid Phase ◽  
Iron Ore ◽  
Sintering Temperature ◽  
Mixed Phase ◽  
Al2o3 Content ◽  
Phase Content ◽  
Sintering Process ◽  
Test Device ◽  
Sintering Characteristics ◽  
Factsage Software

The liquid phase fluidity of iron ore is a vital index of fundamental sintering characteristics. In this paper, FactSage software and a visible microsintering test device were used to research the influence of the thermodynamic melt characteristics on the liquid phase fluidity under fixed CaO content conditions. The results show that the laws governing liquid phase fluidity of iron ore are significantly different with a fixed alkalinity and fixed CaO content of the sample. The liquid phase content at the sintering temperature is the most important thermodynamic melt formation characteristic affecting the liquid phase fluidity. In addition to the liquid phase content, other minerals also have a greater impact on liquid phase fluidity. Decreasing the viscosity of the liquid phase improves the liquid phase fluidity of the iron ore, and the effect of the SiO2 content of the iron ore on the mixed phase viscosity is greater than that of the Al2O3 content.

scholarly journals Effect of TiO2 on the Sintering Behavior of Low-Grade Vanadiferous Titanomagnetite Ore

Materials ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 4376
Author(s):  
Songtao Yang ◽  
Weidong Tang ◽  
Xiangxin Xue
Keyword(s):  
Perovskite Phase ◽  
Calcium Ferrite ◽  
Sintering Behavior ◽  
Low Grade ◽  
Sintering Process ◽  
X Ray Diffraction ◽  
Degradation Index ◽  
Tio2 Content ◽  
Iron Ore Fines

Low-grade vanadiferous titanomagnetite ore (LVTM) is as an important mineral resource for sintering ore manufacturing. Furthermore, TiO2 has a significant effect on the sintering process of iron ore fines. The effects of TiO2 on the metallurgical properties, microstructure, and mineral composition of LVTM sinter were investigated by sintering pot tests, X-ray diffraction (XRD), scanning electron microscopy (SEM), and mineral phase microanalysis. The results were as follows: as the TiO2 content increased from 1.75% to 4.55%, the flame front speed and productivity decreased, while the reduction degradation index (RDI) and softening properties deteriorated. In addition, the tumbler index (TI) values reached a maximum at TiO2 = 1.75%. In addition, with increasing TiO2 content, an increase in the magnetite and perovskite phase, and a decrease in calcium ferrite and hematite were found with an increase in TiO2 content. Thus, the lower the TiO2 content, the better the quality of the sinter.

scholarly journals Iron-Ore Sintering Process Optimization / Optymalizacja Procesu Aglomeracji Rudy Żelaza

2015 ◽  
Vol 60 (4) ◽  
pp. 2895-2900 ◽  
Author(s):  
M. Fröhlichová ◽  
D. Ivanišin ◽  
A. Mašlejová ◽  
R. Findorák ◽  
J. Legemza
Keyword(s):  
Iron Content ◽  
Iron Ore ◽  
Raw Materials ◽  
Size Composition ◽  
Sintering Process ◽  
Iron Ore Sintering ◽  
Iron Ore Sinter ◽  
A Charge ◽  
Iron Ore Concentrate

The work deals with examination of the influence of the ratio between iron ore concentrate and iron ore on quality of produced iron ore sinter. One of the possibilities to increase iron content in sinter is the modification of raw materials ratio, when iron ore materials are added into sintering mixture. If the ratio is in favor of iron ore sinter, iron content in resulting sintering mixture will be lower. If the ratio is in favor of iron ore concentrate and recycled materials, which is more finegrained, a proportion of a fraction under 0.5 mm will increase, charge permeability property will be reduced, sintering band performance will decrease and an occurrence of solid particulate matter in product of sintering process will rise. The sintering mixture permeability can be optimized by increase of fuel content in charge or increase of sinter charge moisture. A change in ratio between concentrate and iron ore has been experimentally studied. An influence of sintering mixture grain size composition, a charge grains shape on quality and phase composition on quality of the produced iron sinter has been studied.

Effect of WC Addition on Phase Formation and Microstructure of TiC-Ni Composites

2008 ◽  
Vol 55-57 ◽  
pp. 353-356
Author(s):  
Nawarat Wora-uaychai ◽  
Nuchthana Poolthong ◽  
Ruangdaj Tongsri
Keyword(s):  
Liquid Phase ◽  
Tungsten Carbide ◽  
Phase Formation ◽  
Liquid Phase Sintering ◽  
Precipitation Process ◽  
Solid Solution Phase ◽  
Binder Phase ◽  
Sintering Process ◽  
X Ray Diffraction ◽  
X Ray

In this research, titanium carbide-nickel (TiC-Ni) composites, with tungsten carbide addition, were fabricated by using a powder metallurgy technique. The TiC-Ni mixtures containing between 0-15 wt. % tungsten carbide (WC), were compacted and then sintered at 1300°C and 1400°C, respectively. The phase formation and microstructure of the WC-added TiC-Ni composites have been investigated by X-ray diffraction and scanning electron microscopy techniques. Mechanical properties of these composites were assessed by an indentation technique. The X-ray diffraction patterns showed no evidence of tungsten rich phases in the sintered WC-added cermets. This indicates that during the sintering process, tungsten carbide particles were dissolved in metallic binder phase (Ni phase) via dissolution/re-precipitation process during liquid phase sintering. The liquid phase formed during sintering process could improve sinterability of TiC-based cermets i.e., it could lower sintering temperatures. The TiC-Ni composites typically exhibited a core-rim structure. The cores consisted of undissolved TiC particles enveloped by rims of (Ti, W)C solid solution phase. Hardness of TiC-Ni composites increased with WC content. Sintering temperature also had a slight effect on hardness values.

Quality Estimation for the Iron Ore Sinter Obtained via Separate Blend Preparation

2020 ◽  
Vol 844 ◽  
pp. 114-123
Author(s):  
Volodymyr Bochka ◽  
Artem Sova ◽  
Lina Kieush ◽  
Oleksandr Hryshyn ◽  
Alisa Dvoiehlazova
Keyword(s):  
Iron Ore ◽  
Mineralogical Composition ◽  
Equivalent Diameter ◽  
Sintering Process ◽  
Iron Ore Sintering ◽  
Positive Effects ◽  
Iron Ore Sinter ◽  
Iron Ore Sintering Process ◽  
Ore Sintering

This paper reveals that obtaining high-quality sinter, improved or stabilized by its size and strength, is a challenge to be solved by embracing both the formation of sinter with the strong structure and the optimal mineralogical composition of its bonds during the preparation of the sintering blend. The existing technological schemes of iron ore sintering do not allow producing the sinter where the amounts of fines with 0-0.5 mm of fraction would be less than the typical amounts of 8.1-20.4%. Therefore, the study to establish how the blend preparation with the preliminary made composites affects the parameters of iron ore sintering process and the quality of the resulting sinter has been carried out. It has determined that the use of separate pre-granulation has commonly positive effects on the process of blend preparation, namely it significantly decreases the amount of non-granulated fraction of 0-1 mm and increases the equivalent diameter of the granules, reduces the standard deviation and variation coefficient, indicating the more homogeneous granulometric composition of raw granules.

Research on Influence Law of Fuel Structure for Low-FeO Sintering

2011 ◽  
Vol 201-203 ◽  
pp. 1802-1805
Author(s):  
Miao Lian Bian ◽  
Sheng Li Wu ◽  
Qing Feng Wang
Keyword(s):  
Liquid Phase ◽  
Solid Fuel ◽  
Iron Ore ◽  
Experimental Results ◽  
Coke Breeze ◽  
Partial Substitution ◽  
Liquid Volume ◽  
Sintering Process ◽  
Bonding Phase ◽  
Sintering Condition

Micro–sintering equipment was applied to simulate sintering process of iron ore. FeO content of sinter-samples under different fuel structures was measured, and then the effect of fuel structure on fluidity of liquid phase and strength of bonding phase were analyzed in this paper. The proper fuel structure was finally discussed under low FeO sintering condition. The results show that: when anthracite was adopted as partial substitution of coke breeze as part of solid fuel, FeO of sinter reduces and self-strength of bonding phase increases. Although fluidity of liquid phase reduces, the fluidity index it is still above 0.8, which can meet the liquid volume needed for sintering. When CDQ powder is used as part of solid fuel, FeO of sinter also reduces, but fluidity of liquid phase and self-strength of bonding phase reduce a little due to its low combustibility. Taking experimental results and practical production together into account, it can be concluded that proper fuel structure that meets low FeO sintering should be “70% coke+30% anthracite”.

scholarly journals Influence of iron ore concentrate on the characteristics of sintering and reduction of sinter

2020 ◽  
pp. 24-24
Author(s):  
H. Guo ◽  
F.-M. Shen ◽  
X. Jiang ◽  
D.-W. Xiang ◽  
H.-Y. Zheng
Keyword(s):  
Liquid Phase ◽  
Calcium Silicate ◽  
Iron Ore ◽  
Raw Materials ◽  
Mineral Resources ◽  
Integral Form ◽  
Sio2 Content ◽  
Calcium Ferrite ◽  
Iron Ore Sintering ◽  
Bonding Phase

As the main iron ore importing country for China, the abundant mineral resources of Australian are the primary raw materials for the sintering production. To better understand the properties of different iron ore from Australia and then guide the sintering production, this study selected four types ore from Australian and one type ore from domestic, and their properties were investigated under different condition. The experiment of single iron ore sintering was studied to examine the influence of different iron ore on metallurgical properties of sinter. From this study, the following results were obtained: GG showed poor fluidity and higher assimilability temperature, but the bonding phase strength was the highest; YD showed better fluidity and lower assimilability temperature, whereas SJY (domestic ore) showed better fluidity and higher bonding phase strength, lower assimilability temperature. The influence mechanism of iron ore on the fluidity was further analyzed by using SEM and ion theory of slag. With the increase SiO2 content of iron ore, the fluidity index increased, the main reason was that the amount of liquid phase increased and melting point decreased during sintering. However, an excessive amount of SiO2 caused the decrease of fluidity index of iron ore, the main reason was that the fluidity of the liquid phase itself decreased and secondary hematite appeared. In the case of the SiO2 content of iron ore was higher, the main bonding phase was calcium silicate. With the decrease of SiO2 content, the calcium silicate transformed into calcium ferrite. This main reason was that the Gibbs free energy of calcium ferrite and dicalcium ferrite (2CaO?SiO2) was higher than that of calcium silicate in the temperature ranges of 400-1600 K. The reduction degree of YD was the highest in all the cases and that of GG was the lowest. Activation energies of 5.39, 3.14, 3.51, 4.47 and 2.92 kJ/mol were obtained for the reduction of GG, PB, BH, SJY, and YD, respectively. In all the cases, the reaction corresponded to the model function of F1(?), and the integral form was -ln(1-?)=kt. Through this investigation, it could be concluded that the most appropriate ore category for sinter pot was YD.

Investigation of a granule structure that focused on reducing NOx emissions in sintering process

2019 ◽  
Vol 116 (3) ◽  
pp. 315
Author(s):  
Junmao Qie ◽  
Chunxia Zhang ◽  
Haifeng Wang ◽  
Yuhua Guo ◽  
Shengli Wu
Keyword(s):  
Iron Ore ◽  
Calcium Ferrite ◽  
Emissions Reduction ◽  
Test Results ◽  
Sintering Process ◽  
Sinter Quality ◽  
Iron Ore Sintering ◽  
Granule Structure ◽  
Iron Ore Sintering Process ◽  
Ore Sintering

The pressure to reduce NOx emissions in iron ore sintering process is enlarging increasingly. The paper proposed a sintering granulation method to reduce NOx emissions. The main character of the method was to wrap all fuel on the surface of the pellet, and also increased the contact between iron ore and fluxes. The sinter-pot test results showed that NOx emissions of the method reduced by 19.9% and sinter quality improved, while SO2 emissions increased by 17.7% compared with that of the conventional method. The increase in the reducing atmosphere of the sinter bed and the development of calcium ferrite in sinter were the main causes of NOx emissions reduction and the improvement of the sinter quality. In addition, the promotion of the combustion of fuel resulted in the increase in SO2 emissions. The improvement of the sinter quality and the control of the sintering flue gas pollutants can also be realized through adjusting the distribution of fuel, fluxes and iron ore in the pellet reasonably.

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