Selective underground mining of complex structured ore bodies of Kryvyi Rih Iron Ore Basin

Abstract

Selective mining of complex structured ore bodies will enable increased iron content in the mined ore mass in underground mining at Kryvyi Rih iron ore basin applying the existing mining systems. The article determines the way the grade changes in a mine block of a complex structured ore body when applying bulk and selective mining as well as factors influencing indices of extracting ore mass from the block. The investigation results prove that it is reasonable to mine complex structured ore deposits with barren inclusions applying selective mining if the iron content in the block varies from 64 to 67% and horizontal thickness of the barren inclusion makes 4 – 12 m. At that, the thickness ratio should not exceed 0.3. Stoping methods should be applied to receive high indices of ore mass extraction. There is determined an ore/barren inclusion-to-ore body thickness ratio considering the dilution factor that confirms practicability of selective mining of complex structured ore bodies. Selective mining of complex structured ore deposits of Kryvyi Rih iron ore basin applying open stoping enables increasing the mined ore mass quality without considerable capital and operating costs and, consequently, staying on the market and enhancing the environmental situation in the region.

The study of the stress-strain state of the massif in mining uranium at “VOSTGOK” deposits

“…The solution for leaching uranium ores is fed from the existing workings over the room of the upper block. At this, volumes of mining are cut and pipes are again used for feeding the working solution to blocks [1][2][3].…”

“…Determining permissible dimensions of main structural element of room mining systems [main regulatory documents [1,2] however, do not consider the influence of the ore bed dip and are not intended for determining the safe thickness of a roof. The technology of underground block leaching of uranium ores in vertical double blocks is a new one to be applied at VostGOK underground mines and requires scientific support [4][5][6][7].…”

Research of new methods for quality air control after massive explosions in the open mine industry

“…=P (300/5 · 30) + (300/5 · 5) = 2100 m (2) It is also necessary to take into account the distance from the shelter to the mass explosion area, in this case P shelter = 2 × 1000 m = 2000 m. Generally, UAVs must travel a distance of at least 3 km in order to carry out measurements in the mass explosion area.…”

“…Proven reserves of the iron ore for Kryvorizkyi Iron Ore Basin are one of the largest in Europe, about 32.2 billion tons, with an iron content in the ore from 22-65% [1][2][3][4]. Mining works are carried out using open and underground methods.…”

Development of resource-saving technology when mining ore bodies by blocks under rock pressure

“…Kryvyi Rih iron ore basin accounts for over 32.2 bn t of iron ores with iron content in the massif of 24-65% that are mined by underground and open-pit methods. Iron ores with the useful component content of 60-65% are mined applying bulk-caving methods on the compensatory area or open stoping and further caving of enclosing rocks [1][2][3][4].…”