METHOD OF MINING ORE BODIES Russian patent published in 2023 - IPC E21C41/22 

FIELD mining industry.

SUBSTANCE: invention can be used in the mining of ore bodies that bifurcate downward. The method of mining ore bodies using double close-in hexagonal pillars using the method of isolated zones of secondary loosening includes drilling exhaust and sublevel drilling workings in ore areas, drilling fan holes, forming lower angular end bevels of pillars by mining inclined layers at an angle of 45°-ϕ/2, where ϕ is the angle of internal friction of broken ore, expansion of the ends of the outlet workings. Double closely spaced pillars are formed on both sides of the rock layer. Together with them, the ore section above the rock layer is mined, achieving finer grinding of the ore than in the rest of the mass by moderately thickening the pattern of wells, which prevents over-grinding of the ore and increases the yield of dusty particles, increasing the cohesion of the ore pieces. In this case, the upper side bevels of the rock layer are formed at an angle of 45°-ϕ/2, serving to move the squeezed out ore. The bevels are placed at a height at which the total damage from the cut off triangle of ore and rock cuts will be minimal. A greater degree of ore crushing above the rock layer increases the rate of its flow and the completeness of extraction. Mass release is carried out from all outlet workings in a parallel, uneven mode with the formation of isolated zones of secondary loosening, which thereby lose their bearing capacity. This causes a concentration of support pressure above the rock layer and extrusion of ore along the planes of its bevel. At the last stage of the cleaning cycle, the remaining protrusions are worked off in inclined layers together with the angular bevels of the next adjacent pillars, forming the next outlet slots.

EFFECT: ensuring a reduction in losses and dilution at high productivity in the conditions of mining complex-structured ore bodies.

1 cl, 6 dwg