Representative temperature at minimum energy content of ore and mineral milling in super high frequency heating

The ore milling method with preliminary heating of ore samples by SHF electromagnetic waves of different length is used in the studies. The SHF-treated sample and the unexposed initial sample were then separately milled in an impact testing machine by a gravity load falling from a certain height. As a result, the plots of specific energy content of milling as function of SHF treatment duration were obtained. The internal structural changes and micro cracking under SHF heating are connected with nonuniform heating of dissimilar minerals with different thermophysical properties. Different minerals of rocks and ore absorb energy of SHF waves and convert it to thermal energy. The relation of the heat capacity of rock and ore minerals and the SHF treatment duration and, consequently, temperature is obtained. Using the heat capacity formula and the functional relationship of the temperature and SHF treatment duration, the temperature–SHF treatment time curves are plotted for different rocks and for quartz. A new temperature characteristic of rocks and ore is experimentally discovered—the critical softening temperature fitting the minimum energy content of milling at the lowest temperature.

Tazhibaev K. T., Sultanalieva R. M., Makanov K. M., Tazhibaev D. K. Representative temperature at minimum energy content of ore and mineral milling in super high frequency heating. MIAB. Mining Inf. Anal. Bull. 2020;(9):65-76. [In Russ]. DOI: 10.25018/0236-14932020-9-0-65-76.

Tazhibaev K.T.¹, Dr. Sci. (Eng.), Professor, Head of Laboratory, e-mail: kushbak@yandex.ru,
Sultanalieva R.M., Dr. Sci. (Phys. Mathem.), Professor, Prorector on Scientific Work and External Relations, I. Razzakov Kirghiz State Technical University, Bishkek, Kirghiz Republic,
Makanov K.M.¹, Graduate Student,
Tazhibaev D.K.¹, Cand. Sci. (Eng.), Head of Laboratory,
¹ Institute of Geomechanics and Development of Bowels, National Academy of Sciences of Kirghiz Republic, Bishkek, Kirghiz Republic.

Tazhibaev K.T., e-mail: kushbak@yandex.ru.

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