Published Dec 7, 2015


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Manuel Diaz, BSc

Ivan Amaya, PhD

Rodrigo Correa-Cely, PhD



This article shows the main experimental results related to the measurement of dielectric properties of Pyrite ore mineral samples as a function of temperature, and their effect on the heating behavior of the samples. It was found that the sample’s dielectric properties strongly depend on temperature. The best model for  and  that fitted the experimental data, was a Gaussian model. Besides, and under certain conditions, it was possible to roast the mineral even better than with an electric furnace, while requiring less processing time and with lower electrical energy consumption. Additional exploratory tests revealed that microwaves can be used to smelt a roasted mineral ore with time reductions of about 90%, while keeping recovery margins above 95%. Thus, we conclude that, as a next stage, the process should be directed to using a single mode applicator, for processing higher volumes of mineral at pilot plant scale.


Tostación, oro, mineral, calentamiento microondas, fundiciónRoasting, gold, mineral ore, microwave heating, smelting

[1] Keysight Technologies, “Application note: basics of measuring the dielectric properties of materials.” Keysight Technologies, pp. 1–34, 2015.
[2] Y. Zhao, Y. Hou, Y. Cui, H. Liang, and L. Li, “Recovery of copper from copper sulfide concentrate by sulfation roasting,” Int. J. Nonferrous Metall., vol. 04, no. 2, pp. 9-13, Apr. 2015.
[3] X. Ma, M. Zhang, F. Min, T. Ge, and C. Cai, “Fundamental study on removal of organic sulfur from coal by microwave irradiation,” Int. J. Miner. Process., vol. 139, pp. 31-35, Jun. 2015.
[4] T. Agacayak and M. Koseler, “Effect of microwave heating on the leaching of lateritic nickel ore in perchloric acid,” J. Chem. Soc. Pakistan, vol. 37, no. 2, pp. 230-235, Apr. 2015.
[5] Z. Li, J. Li, L. Zhang, J. Peng, S. Wang, A. Ma, and B. Wang, “Response surface optimization of process parameters for removal of F and Cl from zinc oxide fume by microwave roasting,” Trans. Nonferrous Met. Soc. China, vol. 25, no. 3, pp. 973-980, Mar. 2015.
[6] S. Singh, D. Gupta, V. Jain, and A. Sharma, “Microwave processing of materials and applications in manufacturing industries: a review,” Mater. Manuf. Process., vol. 30, no. 1, pp. 37-41, May 2015.
[7] M. Wang, P. Xian, X. Wang, and B. Li, “Extraction of vanadium from stone coal by microwave assisted sulfation roasting,” JOM, vol. 67, no. 2, pp. 369-374, Feb. 2015.
[8] Z. Guo, T. Lei, W. Li, H. Luo, S. Ju, J. Peng, and L. Zhang, “Clean utilization of CuCl residue by microwave roasting under the atmosphere of steam and oxygen,” Chem. Eng. Process. Process Intensif., vol. 92, pp. 67-73, Jun. 2015.
[9] K. Hara, M. Hayashi, M. Sato, and K. Nagata, “Continuous pig iron making by microwave heating with 12.5 kW at 2.45 GHz,” J. Microw. Power Electromagn. Energy, vol. 45, no. 3, pp. 137-147, 2011.
[10] O. Peltosaari, P. Tanskanen, E.-P. Heikkinen, and T. Fabritius, “Α→Γ→Β-phase transformation of spodumene with hybrid microwave and conventional furnaces,” Miner. Eng., pp. 1-7, Apr. 2015.
[11] E. R. Bobicki, Q. Liu, and Z. Xu, “Microwave heating of ultramafic nickel ores and mineralogical effects,” Miner. Eng., vol. 58, pp. 22-25, Apr. 2014.
[12] W. Zhao, J. Chen, X. Chang, S. Guo, C. Srinivasakannan, G. Chen, and J. Peng, “Effect of microwave irradiation on selective heating behavior and magnetic separation characteristics of Panzhihua ilmenite,” Appl. Surf. Sci., vol. 300, pp. 171-177, May 2014.
[13] M. Lovás, M. Kováčová, G. Dimitrakis, S. Čuvanová, I. Znamenáčková, and Š. Jakabský, “Modeling of microwave heating of andesite and minerals,” Int. J. Heat Mass Transf., vol. 53, no. 17-18, pp. 3387-3393, Aug. 2010.
[14] Y. Wang and N. Djordjevic, “Thermal stress FEM analysis of rock with microwave energy,” Int. J. Miner. Process., vol. 130, pp. 74-81, Jul. 2014.
[15] I. Amaya and R. Correa, “Electromagnetic heating as a way of cutting costs while saving energy: Time evolution,” Rev. Ing. Univ. Medellín, vol. 11, no. 20, pp. 215-226, Jun. 2012.
[16] R. Meredith, Engineers’ Handbook of Industrial Microwave Heating. London: The Institution of Electrical Engineers, 1998.
[17] X. J. Su, S. J. Ma, C. L. He, and Y. Q. Chen, “Direct microwave roasting of arsenic- bearing pyrite concentrates,” J. Microw. Power Electromagn. Energy, vol. 48, no. 2, pp. 81-88, 2014.
[18] R. Correa, F. Ortiz, and R. Cruz, “Medición en línea de la temperatura de una muestra en una cavidad de microondas,” Rev. Fac. Ing. Univ. Antioquia, no. 52, pp. 123-133, Mar. 2010.
[19] B. Nanthakumar, C. Pickles, and S. Kelebek, “Microwave pretreatment of a double refractory Gold ore,” Miner. Eng., vol. 20, no. 11, pp. 1109-1119, Sep. 2007.
[20] R. K. Amankwah and G. Ofori-Sarpong, “Microwave heating of gold ores for enhanced grindability and cyanide amenability,” Miner. Eng., vol. 24, no. 6, pp. 541-544, May 2011.
[21] R. K. Amankwah, A. U. Khan, C. A. Pickles, and W. T. Yen, “Improved grindability and gold liberation by microwave pretreatment of a free-milling gold ore,” Miner. Process. Extr. Metall., vol. 114, no. 1, pp. 30-36, Mar. 2005.
[22] I. Amaya, D. Bernal, S. Garnica, M. Reslen, and R. Correa, “Improved roasting of some Colombian gold ores,” Dyna, vol. 80, no. 178, pp. 70-77, 2013.
[23] J. M. Catalá Civera, J. D. Gutiérrez Cano, F. L. Peñaranda-Foix, and B. Garcia-Baños, “Portable system for dielectric characterization of materials at microwave frequencies,” in 13th International Conference on Microwave and RF heating, AMPERE 2011, 2011, pp. 137-140.
[24] A. J. Canos, F. L. Penaranda-Foix, J. M. Catala-Civera, and B. Garcia-Banos, “Measurement of dielectric properties at high-temperatures in real-time with cylindrical cavity,” in 2010 IEEE MTT-S International Microwave Symposium, 2010, pp. 1044-1047.
How to Cite
Diaz, M., Amaya, I., & Correa-Cely, R. (2015). Microwave enhanced roasting for pyrite ore samples with dielectric properties strongly dependent on temperature. Ingenieria Y Universidad, 20(1), 63-84.
Electrical and computer engineering