METHOD FOR TAMPING OF BLAST DOWN HOLES IN SINGLE BLASTS IN OPENCAST MINES Russian patent published in 2009 - IPC F42D1/08 

FIELD: blasting.

SUBSTANCE: invention is related to mining industry and construction, namely to methods for tamping of blast down holes in single blasts in opencast mines. Method includes installation of additional tamping from loose finely dispersed material in upper non-charged part of shot holes directly above explosive charge (EC) for the length from 6 to 12 diameters of shot hole, and then hydraulic stem bag is provided in the form of tight shell filled with water. Water of hydraulic stem bag is acidified till 4≤pH≤5.5. Additional tamping is made of two parts installed one above the other and consisting of different materials, at that lower part of this tamping consists of inertial material, and upper part - from neutraliser of poisonous gases produced in explosion of EC blasting, and has length from 1 to 6 diameters of hole. Inertial material used is natural sand. Neutraliser of poisonous gases produced in process of EC blasting is ground chalk with particle size of up to 40 mcm.

EFFECT: increased efficiency of dust and gas suppression, extent and quality of blasted mined rock grinding, provision of more complete performance of blasting reaction, reduction of quantity of poisonous gases, produced after blasting of EC, increased duration of explosion gases action at shot hole walls.

5 cl, 2 dwg, 2 tbl, 6 ex