Q. Like et alii, Frattura ed Integrità Strutturale, 34 (2015) 543-553; DOI: 10.3221/IGF-ESIS.34.60 543 Meso-mechanics simulation analysis of microwave-assisted mineral liberation Qin Like, Dai Jun School of Architecture and Civil Engineering Xi’an University of Science and Technology, Xi’an 710054, P.R China Yuan Liqun School of Architecture and Civil Engineering, Liaocheng University, Liaocheng 252059, P.R China A BSTRACT . Microwave-assisted crushing and grinding can improve efficiency and reduce energy consumption. This paper takes rock grains with galena and calcite as the research object to establish a two-dimensional computational model through the finite difference software FLAC2D. It analyzes the process and law of mineral boundary failure under microwave irradiation, and assesses the effects of four factors, namely, microwave irradiation time, power density, mineral crystal size, and mineral content, on mineral boundary failure. Results indicate an optimal microwave irradiation period for the rapid failure of mineral boundary. Moreover, irradiation time and energy consumption can be reduced by increasing the microwave power density. However, irradiation time and energy consumption are basically unchanged when the microwave power density is above a certain threshold. Mineral content slightly affects the microwave irradiation time, whereas mineral crystal size significantly affects the microwave irradiation time. In addition, a larger-sized mineral crystal requires less irradiation time and energy consumption to reach the same failure rate. However, irradiation time and energy consumption slightly change when the crystal size is larger than a certain value. K EYWORDS . Microwave heating; Assisted liberation; Meso-mechanics simulation; Irradiation time; Energy consumption. I NTRODUCTION icrowave is an ultra-high frequency electromagnetic wave with a wavelength of 1 mm~1 m. It can be used for heating [1]. Compared with conventional heating, microwave heating has advantages of internal heating, rapid heating, selective heating, and simple control; therefore, microwave heating is extensively used in various fields, such as food, agriculture, medical, and metallurgy [2-5]. Microwave heating can also be utilized for sorting minerals, which can effectively improve sorting efficiency and reduce energy consumption. Different minerals produce various heating characteristics under microwave irradiation due to diverse dielectric properties [6]. The results indicate that several gangue minerals, such as quartz, calcite, and muscovite, are classified as electromagnetic wave-transparent materials that are difficult to heat by microwave; however, some ores, primarily sulfide mineral, iron oxide ores, such as copper, lead sulfide, pyrite, manganese oxide, and many other useful minerals, are microwave-absorbing materials, which can be heated in a very short time in the microwave field [7, 8]. Therefore, in the microwave irradiation process, a large temperature M