Peregudov V. Improving the efficiency of blasting in difficult geological conditions of iron ore deposits.

The objective is to ensure the effectiveness of blasting in deep iron pit in order to achieve uniform crushing rocks with a given size of the average piece of blasted rock mass. Analytical probability distribution of blasted rock pieces and the theoretical dependence of the average piece in the collapse on the parameters of blasting were set. Dependences of the excavation equipment productivity on the size distribution of rock mass were used to calculate economically reasonable values of the powder factor. Laboratory and experimental studies have revealed patterns of change in the work of destruction of blown ferruginous quartzite and ball mill performance from the powder factor. Designed blasting parameters taking into account the influence of the powder factor to further processes of production and processing to meet the requirements for particle size distribution undermined rock mass, rock properties and uniformity of explosives distribution in the block. Developed parameters were incorporated into standard blasting designs of Hannivskyy and Pershotravnevyy quarries of the PJSC "Northern Mining and Processing Plant". Estimated economic effect of undermining 1 million m3 of ore is 488.5 ths. hrv., when doing stripping 85.7 ths. hrv. Branch - mine-metallurgical.