Articles
All articles | Recent articles
Microstructure and Properties of Carbon Block Refractories Containing Thermally Oxidized Anthracite for Blast Furnaces
T. Wang, S. Sang, Y. Li, Y. Xu, Q. Wang
The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081, PR China
received October 10, 2017, received in revised form November 23, 2017, accepted December 4, 2017
Vol. 9, No. 1, Pages 85-92 DOI: 10.4416/JCST2017-00081
Abstract
Carbon block refractories containing thermally oxidized anthracite (TOA) and additives of Al and Si were prepared for use in blast furnaces. The TOA was obtained by treating electrically calcined anthracite (ECA) using the thermal oxidation method. It was then introduced into carbon blocks by partially or totally replacing the ECA raw materials. The microstructure and properties of carbon block refractories heated in a coke bed at 1400 °C were investigated. The results revealed that TOA accelerated the formation of β-SiC whiskers and β-Sialon phases in carbon block refractories because TOA has higher reactivity than ECA. Properties such as the cold compressive strength, mean pore diameter, < 1 μm pore volume ratio and thermal conductivity of carbon block refractories with TOA were improved remarkably compared with those without TOA. It was suggested that the in-situ-formed ceramic phases in the matrix and on the aggregates both had a strengthening effect on the carbon block refractories. Moreover, the whiskers formed in the matrix were more favorable for forming an excellent microporosity structure as they filled the pores while the whiskers on the aggregates were more beneficial for reducing the interface thermal resistance between the aggregates and matrix, thus promoting the thermal conductivity of the carbon block refractories.
Download Full Article (PDF)
Keywords
Thermally oxidized anthracite, microstructure, thermal conductivity, carbon block refractories
References
1 Zhang, G.L., Ma, L.Q., Xiang, Z.L., Zhang, J.P.: Selection of materials and property of carbon blocks for blast furnace, Carbon Techniques, 6, 44 – 47, (2003).
2 Liu, Z.J., Zhang, J.L., Zuo, H.B., Yang, T.J.: Recent progress on long service life design of Chinese blast furnace hearth, ISIJ International, 52, 1713 – 1723, (2012).
3 Li, Y.W.: Optimization of microstructure and performance of refractories for blast furnace hearth. 2014, PhD Dissertation, Wuhan University of Science and Technology.
4 Jiao, K.X., Zhang, J.L., Liu, Z.J., Xu, M., Liu, F.: Formation mechanism of the protective layer in a blast furnace hearth. Int. J. Min., Met. Mater., 52, 1713 – 1723, (2012).
5 Hao, Y.Z., Hao, Q.: Selection of local supplied material for blast furnace bottom and hearth lining and lining structure, Ironmaking, 24, 39 – 42, (2005).
6 Chen, X.L., Li, Y.W., Li, Y.B., Jin, S.L., Zhao, L., Ge, S.: Effect of temperature on the properties and microstructures of carbon block refractories for blast furnace, Metall. Mater. Trans. A, 40, 1675 – 1683, (2009).
7 Li, Y.W., Chen, X.L., Sang, S.B., Li, Y.B., Jin, S.L., Zhao, L., Ge, S.: Microstructures and properties of carbon block refractories for blast furnaces with SiO2 and al additions, Metall. Mater. Trans. A, 41, 2085 – 2091, (2010).
8 Chen, X.L., Li, Y.W., Sang, S.B., Zhao, L., Jin, S.L., Li, S.J.: Properties and microstructures of blast furnace carbon block refractories with al additions, Ironmak. Steelmak., 37, 398 – 405, (2010).
9 Li, Y.W., Chen, X.L., Li, Y.B., Jin, S.L., Ge, S., Zhao, L., Li, S.J.: Effect of silicon addition on pore structure and thermal conductivity of fired carbon specimens, Naihuo Cailiao, 42, 401 – 404, (2008).
10 Chen, X.L., Li, Y.W., Li, Y.B., Jin, S.L., Ge, S., Zhao, L., Li, S.J.: Effect of silicon particle size on porous structure and thermal conductivity of coked carbon brick, J. Wuhan Univ. Sci. Technol., 32, 155 – 159, (2009).
11 Liao, N., Li, Y.W., Jin, S.L., Xu, Y.B., Sang, S.B., Deng, Z.J.: Combined effects of boron carbide, silicon, and MWCNTs in alumina-carbon block refractories on their microstructural evolution, J. Am. Ceram. Soc., 2016, .
12 Li, Y.W., Sang, S.B., Li, Y.W.: In-situ decomposition of kyanite and its influence on properties of carbon blocks, Bull. Chin. Ceram. Soc., 34, 938 – 950, (2015).
13 Zhu, T.B., Li, Y.W., Sang, S.B., Chen, X.L., Zhao, L., Li, Y.B., Li, S.J.: Microstructure and properties of zircon-added carbon block refractories for blast furnace, Metall. Mater. Trans. A, 43, 4356 – 4363, (2012).
14 Roungos, V., Aneziris, C.G.: Improved thermal shock performance of Al2O3-C refractories due to nanoscaled additives, Ceram. Int., 38, 919 – 927, (2012).
15 Kun, P., Tapaszto, O., Weber, F., Balazsi, C.: Determination of structural and mechanical properties of multilayer graphene added silicon nitride-based composites, Ceram. Int., 38, 211 – 216, (2012).
16 Luo, M., Li, Y.W., Jin, S.L., Sang. S.B., Zhao, L., Li, Y.B.: Microstructures and mechanical properties of Al2O3-C refractories with addition of multi-walled carbon nanotubes, Mater. Sci. Eng., A, 548, 134 – 141, (2012).
17 Li, Y.W., Chen, X.L., Li, Y.B., Sang, S.B., Zhao, L.: Effect of multiwalled carbon nanotubes on the thermal conductivity and porosity characteristics of blast furnace carbon block refractories, Metall. Mater. Trans. A, 41, 2383 – 2387, (2010).
18 Wang, Q.H., Li, Y.W., Sang, S.B., Jin, S.L.: Effect of the reactivity and porous structure of expanded graphite (EG) on microstructure and properties of Al2O3-C refractories, J. Alloy. Compd., 645, 388 – 397, (2015).
19 Zhu, T.B., Li, Y.W., Jin, S.L., Sang, S.B. et al.: Microstructure and mechanical properties of MgO-C refractories containing expanded graphite, Ceram. Int., 39, 4529 – 4537, (2012).
20 Zhu, T.B., Li, Y.W., Luo, M., Sang, S.B. et al.: Microstructure and mechanical properties of MgO-C refractories containing graphite oxide nanosheets (GONs), Ceram. Int., 39, 3017 – 3025, (2012).
21 Gonzalez, D., Montesmoran, M.A., Suarez-Ruiz, I., Garcia, A.B.: Structural characterization of graphite materials prepared from anthracites of different characteristics: A comparative analysis, Energy Fuels, 18, 365 – 370, (2004).
22 Gonzalez, D., Montesmoran, M.A., Garcia, A.B.: Graphite materials prepared from an anthracite: A structural characterization, Energy Fuels, 17, 1324 – 1329, (2003).
23 Atria, J.V., Rusinko, F., Schobert, H.H.: Structural ordering of pennsylvania anthracites on heat treatment to 2000 – 2900 °C, Energy Fuels, 16, 1343 – 1347, (2002).
24 Gonzalez, D., Altin, O., Eser, S., Garcia, A.B.: Temperature-programmed oxidation studies of carbon materials prepared from anthracites by high temperature treatment, Mater. Chem. Phys., 101, 137 – 141, (2007).
25 Li, Y.W., Wang, Q.H., Fan, H.B., Sang, S.B., Li, Y.B., Zhao, L.: Synthesis of silicon carbide whiskers using reactive graphite as template, Ceram. Int., 40, 1481 – 1488, (2014).
26 Wang, T.S., Li, Y.W., Sang, S.B.: Nickel-catalyzed construction of heat conductive network in electrically calcined anthracite (ECA) based carbon blocks, China's Refractories, 26, 31 – 37, (2017).
27 Wang, Y., Alsmeyer, D.C., Mccreery, R.L.: Raman spectroscopy of carbon materials: Structural basis of observed spectra, Chem. Mater., 2, 557 – 563, (1990).
28 Illekova, E., Csomorova, K.: Kinetics of oxidation in various forms of carbon, J. Therm. Anal. Calorim., 80, 103 – 108, (2005).
29 Sharma, H.N., Pahalagedara, L., Joshi, A., Suib, S.L., Mhadeshwar, A.B.: Experimental study of carbon black and diesel engine soot oxidation kinetics using thermogravimetric analysis, Energy Fuels, 26, 5613 – 5625, (2012).
30 Menendez, J.A., Arenillas, A., Fidalgo, B., Fernandez, Y., Zubizarreta, L., Calvo, E.G., Bermudez, J.M.: Microwave heating processes involving carbon materials, Fuel Process. Technol., 91, 1 – 8, (2010).
Copyright
Göller Verlag GmbH