MODIFICATION OF MINERAL RAW MATERIAL BY RADIATION PRE-TREATMENT BEFORE PROCESSING: FEATURES AND PROSPECTS

Abstract

The earlier case-studies of rebellious lead-zinc ore with grain size of -3 mm at the Chinakal Institute of Mining and Budker Institute of Nuclear Physics, Siberian Branch of the Russian Academy of Sciences provided data on improvement of disintegration selectivity and improved dissociation of useful minerals owing to preliminary treatment by a stream of electrons. The goal of this research is the integrated analysis of the change in the strength of core samples of some rocks, such as limestone, hornfels and granite, after their modification by radiation by a stream of high-energy electrons. It is found that the increase in the absorbed radiation dose results in the change in the strength and deformation properties: ultimate compression strength, modulus of deformation and elasticity modulus. In case of limestone, the ultimate uniaxial compression without radiation treatment is 49.11 MPa and drops to 35.24 MPa at the absorbed dose of 15 kGy. In case of granite, the absorption dose of 10 kGy decreases the ultimate compression strength from 68.33 to 35.08 MPa. The energy input in fracture and crushing is estimated on the equipment designed for uniaxial loading of cores at the Chinakal Institute of Mining. The energy input in fracture and crushing make 78.6 and 7004.2 J/kg for initial granite and 30.6 and 4708.8 J/kg for granite modified by radiation. The size of particle after crushing of treated cores reduces from 10.98 to 8.76 mm. The novelty of this study is the found effect of the range coverage in weakening of minerals with grain sizes to 30-50 mm, including cylindrical granite cores with diameters of 30 mm and lengths of 60 mm (equivalent spherical diameter is 43.2 mm) due to the shock waves generated in minerals during deceleration of electrons in the stream. This effect can be utilized to reduce the energy consumption of the pre-treatment technology and to minimize mineral losses in subsequent processing.