Technology for increasing safety of operation of pit-run and motor roads and prevention of dusting of tailings dumps by treatment them by natural bischofite water solutions

Abstract

The ore mined in open pits, the depth of which often exceeds 200 m, is taken out of them as a ruie by dump trucks having capacity of up to 300 t. Provision of safety of pit-run motor transport and uninterrupted open pit operation, particuiariy in wintertime is an important task. Pecuiiarities of pit-run motor roads running presented. Existing methods of preventing winter siipperiness at motor roads considered, their possibilities and drawbacks highlighted. A technology elaborated to prevent the winter slipperiness and dusting of pit-run motor roads by treatment them by natural bischofite (MgCl2•6H2O) water solutions (RPB). The RPB has a density of 1250 kg/m3, freezing temperature -35 °С and is attributed to the substance of 4th class of danger. Dependence of rocks mass freezing temperature on the content of water RPB in it determined. Testing results of industrial technology of prevention winter slipperiness and dusting of motor roads in the open pits of Krivbas, Ukraine presented. The technology includes preliminary preventive treatment of the roads by a water solution of natural bischofite. Recommendations on its concentration, necessary for roads surface treatment were given, depending on the air temperature at various open pit depth and time of treatment commencement after receiving weather forecast. It was recommended to treat the pit-run motor roads by reagent of water RPB on the surface at air temperature down to -3 °С at the depth of more than 100 m - lower -3 °С, at the depth of more than 200 m - lower -5 °С. Recommendations elaborated to prevent dusting of motor roads, dumps and tailings dumps of mining and concentration plants by application natural bischofite water solutions, which effectively fasten the dusting surfaces preventing blowing-off the dust from them.