ORE AVERAGING BY MASSIVE BLASTING IN THE DEVELOPMENT OF COMPLEX-STRUCTURAL QUARRY FAILINGS

Abstract

The development of quarry faces of complex structure requires ensuring uniform distribution of useful components in the mined ore mass. The quality of the ore extracted from the bowels is determined by the content of the useful component. When developing a quarry with a complex structure (even when developing the same ledge block), ore bodies with different physical and mechanical properties and with different contents of a useful component (heterogeneous ore) are always found, which directly affects production,processing stability and, consequently, the technical and economic indicators of mining production.

Currently, a significant number of deposits are characterized by the presence of undefined ore masses with low, medium and high mineral content, where the technology of gross (total) ore extraction is used. In open-pit mining, the provision of ore with an average content depends on the technological scheme of the deposit, which includes the entire complex of mining processes and technical means.

The key process of extraction of solid minerals is drilling and blasting. Therefore, the effectiveness of blasting operations in blocks of complex structure, represented by areas with different rock strengths and different useful component contents, is expressed in obtaining ore of the required degree of crushing and average content. In such deposits, the regulation of the quality of the ore mass is provided by the technology of selective extraction or ore averaging during the gross extraction of ores of various qualities. This requires the development of a new mining technology that will allow mixing ores with different concentrations of a useful component to produce ore with an average content.

The paper proposes a new technology for regulating blasting operations, which will allow obtaining an ore mass of average content and the required lumpiness at the quarry working site.