2015-Sustainable Industrial Processing Summit
SIPS 2015 Volume 3: Takano Intl. Symp. / Metals & Alloys Processing

Editors:Kongoli F, Noldin JH, Mourao MB, Tschiptschin AP, D'Abreu JC
Publisher:Flogen Star OUTREACH
Publication Year:2015
Pages:550 pages
ISBN:978-1-987820-26-3
ISSN:2291-1227 (Metals and Materials Processing in a Clean Environment Series)
CD-SIPS2015_Volume
< CD shopping page

    Solidification of Slags for Application in Cement

    Tiago Ribeiro1; Joao Batista Ferreira Neto1; Joao Faria1; Catia Fredericci1; Fabiano Chotoli1; Andre Nunis1; Bruno Ferraro1; Antonio Malynowskyj1; Valdecir Quarcioni1; Andre Lotto1;
    1INSTITUTE FOR TECHNOLOGICAL RESEARCH, Sao Paulo, Brazil;
    Type of Paper: Regular
    Id Paper: 168
    Topic: 3

    Abstract:

    The use of metallurgical slags in cement production depends on the phases presented in such slags, which are affected by changes in slag composition and in its cooling rate during solidification. In this work, slags with different compositions were melted and solidified in different conditions. The objective is to determine process conditions for obtaining phases that are known for their good cementations properties, such as amorphous phases and tri and di-calcium silicates.
    Samples were characterized by quantitative X-ray diffraction for determination and quantification of phases and X-ray fluorescence for chemical composition. The microstructure of the samples was observed in SEM-EDS and the composition of each phase was also measured. The solidification of the slags was simulated in the FactSage thermodynamic software to analyze the solidification path and compare equilibrium and obtained results.
    Slags with high amorphous phase were obtained for low basicity (CaO/SiO2 = 1.25) and Al2O3 content of 11% for cooling rates higher than 4oC/s . The phases formed in slags with higher basicity (1.4 and 3.8) are less influenced by cooling rate, and different silicates are obtained such as larnite, merwinite, monticellite, akerminate and gehlenite. For slags with basicity of 3.8 the phase RO, that is a solid solution of FeO, MgO, CaO and MnO, and free lime were observed. Both phases can cause expansion during cement hydration.

    Keywords:

    Cement; Modeling; Slag;

    References:

    [1] C. Fredericci, E.D. Zanotto and E.C. Ziemath: Crystallization mechanism and properties of a blast furnace slag glass, Journal of Non-Crystalline Solids, 273 (2000), n. 1-3, 64-75.
    [2] Y. Kashiwaya, T. Nakauchi, K.S. Pham, S. Akiyama and K. Ishii: Crystallization Behaviors Concerned with TTT and CCT Diagrams of Blast Furnace Slag Using Hot Thermocouple Technique, ISIJ International, 47 (2007), n. 1, 44-52.
    [3] L. Gan, C. Zhang, F. Shangguan, F. Hagguan, X. Li: A Differential Scanning Calorimetry Method for Construction of Continuous Cooling Transformation Diagram of Blast Furnace Slag, Mater. Trans. B. Process Metall. Mater. Process. Sci., 43(2012), 460–467.
    [4] N.Y. Mostafa, S.A.S El-Hemaly, E.I. Al-Wakeel, S.A. El-Korashy, P.W. Brown: Characterization and Evaluation of the Hydraulic Activity of Water-Cooled Slag and Air-Cooled slag, Cement and Concrete Research, 31 (2001), 899-904.
    [5] S.S. Jung and I.I. Sohn: Effect of FeO Concentration on the Crystallization of High-Temperature CaO-Al2O3-MgO-FeO Melts, Am. Cerm. Soc., 96(2013), n. 4, 1309-1316.
    [6] C. Shi: Steel Slag – Its Production, Processing, Characteristics and Cementitious Properties, Journal of Materials in Civil Engineering, 16(2004), 230-236.
    [7] M. Gautier, J. Poirier, F. Bodéman, G. Franceschini, E. Véron: Basic Oxygen Furnace (BOF) Slag Cooling: Laboratory Characteristics and Prediction Calculations, International Journal of Mineral Processing, 123(2013), 94-101.
    [8] M. Tossavainen, F. Engstrom, Q. Yang, N. Menad, M. L. Larsson, B. Bjorkman, Characteristics of Steel Slag under Different Cooling Conditions, Waste Management, 27 (2007), 1335-1344.
    [9] H. G. Ryu, Z.T. Zhang, J.W. Cho, G.H. Wen and S. Sridhar: Crystallization Behaviors of Slags through a Heat Flux Simulator, ISIJ International, 50 (2010), n. 8, 1142-1150.

    Full Text:

    Click here to access the Full Text

    Cite this article as:

    Ribeiro T, Ferreira Neto J, Faria J, Fredericci C, Chotoli F, Nunis A, Ferraro B, Malynowskyj A, Quarcioni V, Lotto A. Solidification of Slags for Application in Cement. In: Kongoli F, Noldin JH, Mourao MB, Tschiptschin AP, D'Abreu JC, editors. Sustainable Industrial Processing Summit SIPS 2015 Volume 3: Takano Intl. Symp. / Metals & Alloys Processing. Volume 3. Montreal(Canada): FLOGEN Star Outreach. 2015. p. 339-348.