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Advanced Construction Materials and Technologies
 process almost the totality of CaO is observed, besides a loss on ignition very important, which corroborates the results of the essay of XRD. Finally, in the case of PAVAL, its content in Al2O3 mainly stands out y.
Textures were observed and recorded by reflected light microscope. Due to the fast cooling ,the belite polymorphism transitions are encouraged to take place successively, leading to the formation of complex microstructure, due to twinning or exsolution within the crystals. Belite is presented generally as round shaped, blue colored due to type of etching and crossed parallel striations (Iacobescu et al., 2011).
Belite type cements with industrial wastes were successfully produced at lower temperature (1350- 1390oC), when compared to ordinary Portland cement (OPC), driving to less energy consumption. The need for a lower quantity of raw materials to be extracted from nature for the manufacture of cements and the use of industrial waste reduces the carbon footprint of the cement industry.
4. Acknologements
S. Martínez-Martínez thanks the Ministry of Education, Culture and Sports for a University Professor Training Fellowship.
5. References
Iacobescu R., Koumpouri D., Pontikes Y., Şaban R., Angelopoulos G.N. (2011), Utilization of EAF metallurgical slag in “green” Belite cement, U.P.B. Sci. Bull., Series B, 73, Iss. 1, pp 187-194.
Uchikawa H. (1994), Management strategy in cement technology for the next century: Part 3, World Cement, pp 47.
Lawrence C.D. (2003), The production of Low-Energy Cements, Lea’s Chemistry of Cement an Concrete, Butterworth-Heinemann, Oxford.
Sharp J.H., Lawrence C.D., Yang R. (1999), Calcium sulfoaluminate cements-low energy cement special cement or what?, Advance Cement Research, 11, pp 3-13.
Iacobescu R.I., Koumpouri D., Pontikes Y.,Saban R., Angelopoulos G.N. (2011), Valorisation of electric arc furnace steel slag as raw material for low energy belite cements, Journal of Hazardous Materials, 196, pp 287-294.
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