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The authors identify some factors that govern energy input of borings removal from hole bottom to an unloading point using auger drilling string assembly. Of specific significance appears to be the factor of insufficient reliability of anchor gears and centering devices of the drilling string assembly, which makes continuous drilling impossible without permanent servicing. The article gives the analysis of bench testing data of bearings with antifriction filler for drilling string mounting groups to be serviced outside the areas of drill holes. The design solutions based on the investigation results and aimed to improve reliability of anchor gears and centering devices of an auger drilling string assembly are described.

New results that solve the important scientific task of providing electrical networks with an isolated neutral voltage up to 1000 V in mining enterprises are obtained. The method for measuring the admittance of insulation networks with isolated neutral voltages up to 1000 V, which will provide improved accuracy and speed measurement admittance network insulation, is described. The measurement is made by adjusting the additional conductance to ensure equal quantities of module phase voltage to earth and zero phase-sequence voltage. In this connection the additional conductance corresponds to the admittance of network. The simulation model of a method of measuring the admittance of insulation using the Matlab/Simulink environment is analyzed. The proposed method is simple, as the instrumentation, single-phase voltage transformers that are needed to measure the admittance of network, are in the service manual of the energy management companies.

The author analyzes the method to prevent gas-dynamic events during mechanized mining of karnallite at Upper Kama potassium-magnesium salt deposit. The method ensures efficient gas drainage and relaxation of outburst-hazardous rocks due to a horizontal drainage borehole slotter in the sidewall of a face entry. The data of the mine experimental studies are presented. The time behavior of residual gas content and air sorption indexes of karnallite in the influence zone of the drainage borehole slotter is determined. It has been found expedient to use borehole slotting to prevent gas-dynamic events during mechanized mining of karnallite.

Under discussion are the direct dumping flowsheets applied to remove lower overburden layers at coal series deposits in Kuzbass. The authors present the calculation procedure for the parameters of overburden excavation and re-excavation flowsheets using draglines. It is found how the re-excavation coefficient depends on the place and level of the dragline site. The recommendations on selecting the dragline route in internal dumping are made. The main trends toward expanding the area of application of the direct dumping technology are identified.

The author proposes a promising technology to separate monolith stones and preformed blocks for construction from rocks mass using a diamond rope cutting machine ensuring reduction in labor content, cost and loss as well as enhancing the process production output. The analytical model is developed, and the dependences between the material loss and the technology parameters are found. The main standards are formulated for the technology, and the ways of improving the diamond rope cutting machines design based on material loss minimization are specified.

It has been found that the rated and actual data on methane emission in production headings in some Kuzbass mines disagree. The air and gas control shows that actual methane emission from broken coal is much less than the rated data when a coal shearer has high advance velocity and production output. The authors demonstrate the connection between an average diameter of broken coal fragment, shearer advance velocity and drum rotation speed using Darcy’s law of flow and Langmuir’s adsorption equation. It is found that methane emission from broken coal and natural coalbed methane content relate nonlinearly and that the relationship of absolute methane emission, shear advance velocity and production output has an extremum.

The article gives new experimental data on chemistry, phase composition, structure and physicochemical properties of surface of minerals composing metasomatically altered kimberlite rocks. The authors have determined formation conditions and basic genetic types of mineral micro- and nano-size phases on diamond surface in the form of aluminosilicate minerals, thin coats of clayey minerals, calcite and dolomite bound with carbonate cement, as well as their negative effect on recovery of diamonds by foam separation. The mechanisms and efficient methods of combined energy effects on the natural heterogeneous system of diamond and surface mineral phase are found to rupture hydrophilic mineral films on diamond surface, prevent their repeated formation and reduce diamond loss in processing of diamond-bearing kimberlites.

The authors consider variants of multipurpose use of plant materials-ground green mass of Sosnovsky cow-parsnip. Simultaneous production of aqueous extract possessing depression properties and after-extraction solid residue being a sorbent for ions of gold and finely dispersed gold-bearing particles is one of the ways toward the reduction in cost and environmental impacts of flotation of gold-containing products. The SEM and UV spectrophotomery shows sorption activity of solid residue of cow-parsnip relative to Au³⁺ ions. It is demonstrated that the studied vegetable sorbent is applicable to additional recovery of finely dispersed gold from flotation pulp. The introduction of cow-parsnip instead of xanthogen in treatment of tailings has enhanced efficiency of fine gold recovery.

The experimental test data on magnetic properties of iron-bearing mineral waste materials under radiation-thermal treatment are presented. It is found that the volume magnetic susceptibility of pyrite- and arsenopyrite-containing waste has increased by 5 times on the average. The authors demonstrate that radiation-thermal magnetization and magnetic separation allows production of KOS-3 grade tin concentrate meeting fuming process requirements from waste of Novosibirsk Tin Works.

The article shows predictability of change in energy content and reactive capacity of standard wolframite concentrate after mechanical activation based on the data of X-ray structure analysis during later-on low-temperature (under 100 °С) alkali leaching. It is confirmed that the quantity of energy accumulated during mechanical activation as surface energy and microstrains influences efficiency of the later-on leaching. The authors derive a relation to calculate wolframite leaching recovery depending on structural change energy, initial coarseness and leaching regimes. The method of preliminary mechanical activation of wolframite and the process efficiency criteria offer conditions for energy-saving wolframite concentrate processing directly at mining and processing plants.