METHOD OF DEVELOPMENT OF LOCAL AREAS OF MINERALIZATION IN STRONG ROCKS Russian patent published in 2020 - IPC F42D1/08 F42D3/04 E21C41/30 

FIELD: blasting operations.

SUBSTANCE: invention relates to explosive destruction of rocks using multi-row short-delayed blasting and can be used in open-cast mines for mining of valuable ores using blasting operations in hard rocks. Method of development of local mineralization areas in hard rocks involves testing of blast holes, supply of starting pulse to multi-row short-delayed blasting on cut-line row located second or third from rear edge of block, with deceleration interval in cut row by one step lower than in perpendicular direction along rows of boreholes. During overburden blocks drilling, all blasting wells are tested. Identified local areas of industrial mineralization are separated on the plan of the exploded block and explosion of the overburden block is performed with intervals of deceleration exceeding 300 ms. After the explosion, the boundaries of the local area of mineralization are carried to the surface of rock mass collapse with increase in the contour size by 1–2 m. When non-electric waveguide initiation systems are used, borehole retarders of 3000–5000 ms are installed.

EFFECT: invention makes it possible to minimize displacements of blasted rock mass for preservation of spatial position of primary contacts of ores and empty rocks.

1 cl, 10 dwg