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) |
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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:
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