OPTIMIZATION OF MICROWAVE-INDUCED ROCK SOFTENING FOR KYRGYZ MINING APPLICATIONS

This study investigated the use of microwave irradiation as a pretreatment (softening) method for various rock types. Representative samples of different mineral compositions (diorite, quartz, and phyllite) were exposed to a controlled 700 W microwave system operating at 2.45 GHz for durations ranging from 1 to 9 minutes, followed by cooling under different regimes. After irradiation, the samples were tested for uniaxial compressive strength and specific comminution energy to quantify the softening effect. Depending on mineralogy, the optimal exposure times were typically 3–5 minutes, yielding the greatest weakening of the rock and the largest reduction in grinding energy (up to about a 60% cut in specific energy requirements). Finally, analytical models and an empirical expression for residual stress distribution (post heating and cooling) were developed to relate irradiation time and temperature to subsequent comminution behavior. These results establish baseline conditions for effective microwave pretreatment of different ores.