scholarly journals Influences of Al2O3 and TiO2Content on Viscosity and Structure of CaO–8%MgO–Al2O3–SiO2–TiO2–5%FeO Blast Furnace Primary Slag

Metals ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 743 ◽  
Author(s):  
Tingle Li ◽  
Changyu Sun ◽  
Sunny Song ◽  
Qi Wang
Keyword(s):  
Blast Furnace ◽  
Rotating Cylinder ◽  
Al2o3 Content ◽  
Slag Viscosity ◽  
Tio2 Content ◽  
X Ray ◽  
Viscosity Variation ◽  
Cylinder Method ◽  
Networks Structure ◽  
Ftir And Raman Spectroscopy

In view of the fact that Ti–bearing blast furnace primary slag has been explored limitedly and its viscosity–structural property is not fully understood, the phase compositions, viscosity and structure of CaO–8%MgO–Al2O3–SiO2–TiO2–5%FeO slag are investigated by X-ray diffractometer, rotating cylinder method, Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy respectively, considering the effect of Al2O3 and TiO2. The critical temperature that is defined as the temperature below which the viscosity of slag increases quickly, could be explained by the relative amount of perovskite to melilite from phase compositions analysis. The slag viscosity first increases with increasing Al2O3 content from 10 to 15 mass%, and then decreases with the further increase of Al2O3 to 18 mass%. Increasing TiO2 content continuously lowers the viscosity. FTIR and Raman spectra results show that increasing Al2O3 or decreasing TiO2 content leads to complex Si–O and Ti–O networks structure, corresponding to the slag viscosity variation. The effect of weak linkages of Si–O–Al is more dominant when Al2O3exceeds 15 mass%, which results in the decrease of viscosity.

scholarly journals Roles of MgO and Al2O3 on the Viscous and Structural Behavior of Blast Furnace Primary Slag, Part 1: C/S = 1.3 Containing TiO2

Metals ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 866 ◽  
Author(s):  
Tingle Li ◽  
Changyu Sun ◽  
Sunny Song ◽  
Qi Wang
Keyword(s):  
Blast Furnace ◽  
Network Structure ◽  
Equilibrium Phase ◽  
Phase Region ◽  
Structure Characterization ◽  
Al2o3 Content ◽  
Slag Viscosity ◽  
Stable Operation ◽  
The Difference ◽  
Cylinder Method

This research provides fundamental insight into the roles of MgO and Al2O3 on the viscous and structural behaviors of CaO−SiO2−MgO−Al2O3−10 mass% TiO2−5 mass% FeO (CaO/SiO2 = 1.3) system primary blast furnace slag. The slag viscosity is measured by the rotating cylinder method, which is essential to the efficient and stable operation of a blast furnace. The network structure characterization of the quenched vitreous samples was conducted using Fourier Transformation Infrared (FTIR) and Raman spectroscopy. Unusual viscous behaviors (that the slag viscosity and the activation energy decrease or increase with increasing MgO or Al2O3 content) were observed, corresponding to changes in the network structure certified by FTIR and Raman analyses. It seems that the addition of MgO and Al2O3 prefers to modify the Si−O and Ti−O network in the present slag. When the slag composition reaches 10% MgO and 12% Al2O3, unexpected viscous behaviors (that MgO increases viscosity and Al2O3 decreases viscosity) are discovered. The roles of MgO and Al2O3 could be interpreted by changes in the arrangement structure of ions in liquid, corresponding to changes in the primary equilibrium phase region determined in phase diagrams and variation in the difference between the experimental and liquidus temperature, respectively.

Research on the Viscosity of CaF2-SiO2-Al2O3-CaO-MgO Slag System by the Thermodynamic Software

2013 ◽  
Vol 634-638 ◽  
pp. 42-46
Author(s):  
Yuan She ◽  
Jian Tao Ju ◽  
Zhi Yuan Jiao ◽  
Zhao Hui Zhang
Keyword(s):  
Physical Properties ◽  
Systematic Study ◽  
Mass Fraction ◽  
Slag System ◽  
Graphite Crucible ◽  
Rotating Cylinder ◽  
Slag Viscosity ◽  
Measuring Apparatus ◽  
Refining Slag ◽  
Cylinder Method

In order to find out a method of computation on the viscosity of CaF2-SiO2-Al2O3-CaO-MgO slag system, which is accurate, rapid and convenient, a systematic study has been carried out. The refining slag samples have been made by the method of rotation-regression-orthogonal combination design during the test. When the temperature of the flux of the samples were 1600°C~1400°C, the experiment was performed by internal rotating cylinder method involving a spindle with the RTW-10 flux physical properties measuring apparatus in graphite crucible per 50°C, meanwhile, the viscosity of slag system were estimated by thermodynamic software FactSage per 50°C. Then, according to the viscosity results of calculation at 1600°C, the viscosity calculation equation was established, which was the relation of the mass fraction of every components and the value of the slag viscosity. Furthermore, the interaction of two components on the influence of the viscosity of slag was discussed.

Influence of Nb2O5 and basicity on the viscosity and structure of CaO-SiO2-Nb2O5-CeO2-CaF2 slag system

2020 ◽  
Vol 117 (3) ◽  
pp. 307
Author(s):  
Zhuang Ma ◽  
Zengwu Zhao ◽  
Wentao Guo ◽  
Zhi Wang
Keyword(s):  
Activation Energy ◽  
Slag System ◽  
Rotating Cylinder ◽  
Degree Of Polymerization ◽  
X Ray Diffraction ◽  
Structural Units ◽  
X Ray ◽  
Reducing Atmosphere ◽  
Bayan Obo ◽  
Cylinder Method

In order to utilize niobium concentrate of Bayan Obo effectively, the effect of Nb2O5 and basicity on the viscosity of CaO-SiO2-Nb2O5-5.0 wt.% CeO2-5.0 wt.% CaF2 slag system was studied from 1653 to 1813 K in reducing atmosphere by rotating cylinder method. For the same condition, the as-quenched samples were investigated through X-ray diffraction and Raman spectroscopy. The results show that the viscosity, break temperature and activation energy of viscous flow decrease with the increase of Nb2O5 and basicity. Raman spectra show that the Nb4+ ions exist in the form of [NbO6] octahedron with different distortion and little [NbO4] tetrahedron in the slags. The Nb2O5 addition and basicity lower the degree of polymerization, where the complex Si-O network is depolymerized into simple structural units.

scholarly journals Effect of Basicity and Al2O3 on Viscosity of Blast Furnace Slag and Thermodynamic Analysis

2021 ◽  
Author(s):  
Jian Zhang ◽  
Zhengjian Liu ◽  
Jianliang Zhang ◽  
Cui Wang ◽  
Hengbao Ma ◽  
...  
Keyword(s):  
Activation Energy ◽  
Thermal Stability ◽  
Blast Furnace ◽  
Constant Temperature ◽  
Slag Basicity ◽  
Al2o3 Content ◽  
Wave Number ◽  
Slag Viscosity ◽  
Slag Structure ◽  
Slag Temperature

With the increased use of laterite nickel ore, the impact of high Al2O3 slag on blast furnace smelting has gradually increased. In this paper, the effects of slag basicity and Al2O3 content on slag viscosity and enthalpy change under constant temperature conditions was investigated. The changes in slag structure were analyzed by activation energy and Fourier Transform Infrared (FT-IR) spectroscopy. The relationship between slag components and slag temperature and viscosity when slag heat is reduced was investigated. The results showed that the viscosity first slightly decreased and then significantly increased with increasing basicity at constant temperature. With the addition of Al2O3 content, the viscosity of the slag increases. The activation energy increases with increasing slag basicity and Al2O3. With increasing basicity, the [SiO4]4- tetrahedral unit trough depth becomes shallow, the [AlO4]5- asymmetric stretching band migrates to lower wave numbers, and the slag structure depolymerizes. With the increase of Al2O3 content, the trough of [SiO4]4- tetrahedra deepens and the center of the symmetric stretching band moves to a higher wave number. The [AlO4]5- asymmetric stretching band becomes obvious, indicating the complexity of the slag structure. When the heat decreases, the slag temperature increases as the basicity increases, and the slag thermal stability is better at the basicity of 0.95-1.05. As the Al2O3 content increases, the thermal stability of the slag becomes worse.

scholarly journals Viscosity estimation model of fluorine-containing mold flux for continuous casting

PLoS ONE ◽  
2021 ◽  
Vol 16 (3) ◽  
pp. e0247828
Author(s):  
Zhongyu Zhao ◽  
Junxue Zhao ◽  
Boqiao Qu ◽  
Yaru Cui
Keyword(s):  
Continuous Casting ◽  
Mass Fraction ◽  
Mold Flux ◽  
Rotating Cylinder ◽  
Spectrometric Analysis ◽  
Nonlinear Regression Analysis ◽  
Estimation Model ◽  
X Ray ◽  
Low Viscosity ◽  
Cylinder Method

A viscosity estimation model for fluorine-containing mold flux for continuous casting was investigated based on the Arrhenius formula and the rotating cylinder method combined with nonlinear regression analysis. This model is highly applicable and not limited by the slag of a certain composition. For most slag compositions, the viscosities estimated with this model deviated from the measured values by no more than 10%, which was in better agreement with the measured values than the viscosities estimated by the Riboud, Iida and Mills models. According to the model calculation and experimental detection, a viscosity isogram of CaF2-Na2O-Al2O3-CaO-SiO2-MgO slag was produced, and the mass fraction of CaF2 in the low-viscosity zone was nearly 14%. An X-ray fluorescence spectrometric analysis of slag after the viscosity test showed that CaF2 and Na2O were significantly reduced, and the measured viscosity was greater than the theoretical viscosity due to the volatilization.

scholarly journals Influence of Al2O3 Content on the Melting and Fluidity of Blast Furnace Type Slag with Low TiO2 Content

2018 ◽  
Vol 2018 ◽  
pp. 1-6
Author(s):  
Hao Liu ◽  
Yuelin Qin ◽  
Yanhua Yang ◽  
Qianying Zhang ◽  
Nengyun Deng
Keyword(s):  
Blast Furnace ◽  
Viscous Flow ◽  
Slag System ◽  
Al2o3 Content ◽  
Slag Viscosity ◽  
Flow Activation Energy ◽  
Flow Units ◽  
Precipitated Phase ◽  
Flow Activation ◽  
Furnace Slag

The increasing usage of iron ores with high Al2O3 content significantly increases the amount of Al2O3 in blast furnace slag and consequently affects its performance. This work uses slag sampled on site to study the effects of changes in Al2O3 content on the fluidity of the CaO–SiO2–Al2O3–MgO–TiO2 slag system that is characterized by high Al2O3 and low TiO2 contents, as well as on the phase transition law during the cooling process. Slag viscosity exhibits a rising trend with an increase in Al2O3 content, and Al2O3 in the tested slag is alkaline. The viscous flow activation energy of molten slag rises from 157 kJ/mol to 172 kJ/mol with an increase in Al2O3 content, and the viscous flow units in the slag become large and complicated. When slag is cooled, the main precipitated phase is melilitite. Spinel, perovskite, and olivine are also observed. The crystallization amount of the melilitite phase decreases constantly with an increase in Al2O3 content.

Study on Viscosity of Titania Bearing Blast Furnace Slag

2011 ◽  
Vol 467-469 ◽  
pp. 1742-1745 ◽  
Author(s):  
Jin Zhu Zhang ◽  
Ling Wen ◽  
Ming Hua Long ◽  
Bi Neng Yang
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Orthogonal Design ◽  
Al2o3 Content ◽  
Slag Viscosity ◽  
Iron And Steel ◽  
Analytical Reagent ◽  
Bf Slag ◽  
Furnace Slag

The viscosity of blast furnace slag which was taken from Shuicheng Iron and Steel Group Co. Limited was experimentally measured by column whirling method using the ND-II slag viscosity tester. By adding analytical reagent CaO, SiO2, Al2O3, MgO and TiO2 in accordance with orthogonal design, the contents of compositions in slag were adjusted in CaO/SiO2=1.16-1.24, 14.06-17.06mass%Al2O3, 5-7mass%TiO2, 8.96-9.96mass%MgO. The results showed that the viscosity of BF slag decreased with increasing TiO2; when the Al2O3 content in the slag was 14.06%, the viscosity of BF slag had a lowest value, a highest value had for 15.56% Al2O3 content, and a lower value for 17.06% Al2O3 content. There is no significant effect on the viscosity by both the magnesia and the binary basicity.

Viscosity Evaluation of Multi-phases Flux by Rotating Cylinder Method

2009 ◽  
Vol 95 (12) ◽  
pp. 807-812 ◽  
Author(s):  
Sohei Sukenaga ◽  
Shinichiro Haruki ◽  
Yoshinori Yamaoka ◽  
Noritaka Saito ◽  
Kunihiko Nakashima
Keyword(s):  
Rotating Cylinder ◽  
Cylinder Method

scholarly journals Thermal, Viscoelastic, Mechanical and Wear Behaviour of Nanoparticle Filled Polytetrafluoroethylene: A Comparison

Polymers ◽  
2020 ◽  
Vol 12 (9) ◽  
pp. 1940 ◽  
Author(s):  
Levente Ferenc Tóth ◽  
Patrick De Baets ◽  
Gábor Szebényi
Keyword(s):  
Room Temperature ◽  
Filler Content ◽  
Research Work ◽  
Tensile Modulus ◽  
Al2o3 Content ◽  
Wear Behaviour ◽  
X Ray ◽  
Mechanical Stirring ◽  
Wear Analysis ◽  
Sintering Method

In this research work, unfilled and mono-filled polytetrafluoroethylene (PTFE) materials were developed and characterised by physical, thermal, viscoelastic, mechanical, and wear analysis. The applied fillers were graphene, alumina (Al2O3), boehmite alumina (BA80), and hydrotalcite (MG70) in 0.25/1/4/8 and 16 wt % filler content. All samples were produced by room temperature pressing–free sintering method. All of the fillers were blended with PTFE by intensive dry mechanical stirring; the efficiency of the blending was analysed by Energy-dispersive X-ray spectroscopy (EDS) method. Compared to neat PTFE, graphene in 4/8/16 wt % improved the thermal conductivity by ~29%/~84%/~157%, respectively. All fillers increased the storage, shear and tensile modulus and decreased the ductility. PTFE with 4 wt % Al2O3 content reached the lowest wear rate; the reduction was more than two orders of magnitude compared to the neat PTFE.

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