In mid-May 2014, flooding caused by unprecedented rainfall wreaked havoc_on Serbia. In the night between May 14 and 15, the swollen Kolubara River with its tributaries flooded the Tamnava West Field and Veliki Crljeni coal open-pit mines. The paper describes the course of flood events, the consequences of the outflow of about 214.4 million m3 of water into the depressions of the open-pit mines, and

Part of large-scale industrial test results of milling fineness influence on lead, copper and zinc minerals flotation results in the Rudnik flotation plant are shown in this paper. Based on industrial research it has been concluded that one-stage milling and two-stage classification of complex Pb-Zn-Cu ore leads to so-called “differential milling”. Namely, galena has much faster comminution than other

Realization of good returns in the mining venture needs careful planning, scheduling, design and optimization of all mining activities which are dependent upon reliable resource estimates. The mineral resource estimation method employed in a deposit thus plays a major role in reduction of risks associated in mining. In this study, indicator kriging, ordinary kriging and inverse distance weighting methods

The aim of this study is to investigate the applicability of artificial neural networks (ANN) and game theory in the development of an underground mining method selection model. To realize this, six different ANN models that can evaluate geometric and rock mass properties of an underground mine, environmental factors and ventilation conditions to determine mining methods that satisfy the safety conditions

The theoretical model is proposed, which allows tracing continuation of seismic vibrations after cessation of blast load by the analysis of velocigrams recording on ground surface during underground explosions. The comparison of the model and experimental velocigrams of massive blasts shows validity of elliptical filters for second-order low frequencies in modeling waveforms of the velocigrams. The

The particle size distribution and the material constitution of samples taken from old milltailings of sulfide and oxidized ore are studied. It is shown that more than 50% of gold occurs in fine size grade of −0.044 mm. The method of gas adsorption reveals large specific area in the samples, which is important for re-entrainment and migration of gold and associate components. It is found that gold

The authors present an efficient modification method of X-ray fluorescence separation with mineral and organic luminophores used to adjust spectral and kinetic characteristics of anomalously luminescent diamonds. The mechanism of attachment of luminophores at diamonds and hydrophobic minerals is proved, including interaction between the organic component of emulsions and the hydrophobic surface of

A physical model is created to describe stage-by-stage fracture of rock mass by deep-hole blasting. The analytical dependences are presented for main parameters of massive blasting. The zones of intense and passive crushing are identified in a blasted bench. The formulas are obtained to calculate volumes of different size particles in these zones. The automated determination procedure of particle size

A new method is proposed for predicting rock pressure with regard to statics, kinematics and dynamics. The static approach calculates strain state using the known classical method based on the mining guidelines. The kinematic approach takes into account the weight of overlying strata and makes the kinematic approach more specific. Dynamics is traced as nonlinear deformation in the course of mining

Some of the coal mines use dragline for the overburden removal of coal top as its geometric, since the initial cost is high with low running cost. Most of the draglines operating in Indian mines have conventional analog control under Ward—Leonard method. To improve the efficiency of those, to reduce the power consumption and to provide maintenance-less operation in the electrical system, the microprocessor-based

The article presents studies into the microwave treatment effect on higher recovery of noble metals from rebellious carbonic ore. The rate of refractoriness of carbonic concentrates was determined using a package of thermal testing techniques. Bitumen is an additional criterion of the refractoriness rate of mineral dressing products. The influence of treatment time on heating of a sample is studied

The authors prove connection between the surface activity relative to gas-liquid interface and collecting ability in flotation for derivatives of xanthogenates (xanthogenates of heavy metals). It is shown that at nonstoichiometric ratio of xanthogenate and metallic salt concentrations, colloid particles are formed in solution. The influence of deviation from the nonstoichiometric ratio of xanthogenate

The authors have analyzed relative earth heat infiltration in artificial ground freezing in the context of formation of frozen wall in mine shafts. The artificial ground freezing modeling reveals a considerable dependence of the earth heat infiltration on the thermal properties of ground, process variables of refrigerating plant and time. The relative earth heat infiltration comes to a steady-state

Uniformity index n represents the range of fragment size distribution and it is applied to evaluate fragment size by Rosin and Rammler cumulative distribution function for a muck pile. The uniformity index n of fragment size distribution has been assessed by digital image analysis technique using Split-Desktop for several blasthole parameters and different zones of in-situ rock mass conditions in five

The author studied the process of copper removal from underspoil water at Blyavinskoe and Safyanovskoe copper ore deposits by cementation by iron. The influence of pH, consumption of cementation agent impurity ions Fe3+, Al3+ and Ca2+, as well as timing on the cementation performance was analyzed. The mechanism of the process was determined, and by-reactions resulting in over-consumption of cementation

The article considers the problem on compression of an isotropic medium with a variable-width slot with cohesive zones at the ends. Under the action of tectonic and gravitational forces in rock mass, contact zones appear between the slot surfaces. The author analyzes the case of a number of the contact zones between the slot surfaces. In a part of the contact zone, cohesion of the slot edges takes

The experimental results on operation of electrodynamic separator with pulsed traveling magnetic field in treatment of sand mixtures with metal particles −0.25 mm.

Based on the analysis, generalization and statistical processing of experimental data, the guideline values are determined for the physical and mechanical properties of loamy soil for construction of earthfill dams at liquid mining waste storages. A close parabolic relationship is found between the cohesion, internal friction angle and natural moisture content of soil. The authors present the method

The collected data on long-runout rockslides induced be large-scale underground blasts are presented. The critical conditions of the rockslides are determined as a function of the dynamic impact, rockfall volume, as well as the slope height and gradient. It is shown that the main condition for the mobile rockslides is their volume exceeding 106-108 m3. A collateral effect for rockslides in case of

The theoretical and experimental substantiation of the behavior of ferrous sphalerite in magnetic separation is given in terms of the Gorevka deposit ore. In sphalerite of this deposit, the content of isomorphous iron ranges as 4–9%. The Móssbauer spectroscopy showed the singlet and two doublet lines of iron, demonstrating separate arrays of iron atoms in sphalerite lattice, with formation of Fe-Fe

The classification of the methods available for diagnostic of mining machinery mounting groups with roller bearings is considered with indicated advantages and disadvantages. The model is constructed to describe formation of shock pulses in roller bearings when different defects are generated in them. This model is suitable for the availability monitoring of the machinery mounting groups. The applicability

In this study, the best possible location for an air deck in an explosive column during a surface blasting operation for the most efficient rock fragmentation is described. Volumes of air decks are proposed for the optimization. This study aims at helping guide blasting engineers to easily apply an air deck in a surface blasting operation.

The geophysical investigations are carried out at the Kangalass open pit coal mine using the round penetrating radar and electrical tomography. The main frost effects in rock mass and in water retaining dam are described. The investigation procedure is developed, and the wave fields are characterized. The GPR surveys aimed to reveal water invasion zones in a rock block to be blasted and to trace dynamics

The measurement data on seismic load parameters induced by massive blasting carried out in surface and underground mines are presented. The maximum amplitude of seismic vibrations at the probable depth of potential sources of high-magnitude stimulated-tectonic earthquakes is calculated. These estimates and their comparison with the precision deformography observations show that residual displacements

The authors analyze the structure of the elasticity tensors and compliance coefficients in a special linearly elastic and transversely isotropic material with paradox behavior. The intrinsic moduli and states are found for the elasticity tensors if this material. The extreme values of Young’s modulus, shear modulus and Poisson’s ratio are determined. The characteristics of the nearest tensor of elasticity

The article presents the research findings obtained in deep integrated processing of rebellious high-potassium aluminum silicates from the Kalyum deposit within the Synnyr alkaline massif— synnyrite—with production of alumina as well as potassium and magnesium sulfates. The introduction of magnesium-bearing mineral—dolomite—as an additive at the stage of thermochemical decomposition of the acid-resistant

In the current study, uniaxial compressive strength, Schmidt hammer and Sonic velocity tests are performed on NX size rock core samples from Sakesar and Namal formation limestone. Least square regression analysis is used to develop any possible correlations between the destructive and non-destructive test results. Empirical models, for predicting the uniaxial compressive strength of rocks by using

Sawing of natural stones with diamond-impregnated circular saws is extensively implemented in stone processing plants in variety of applications that include sawing, cutting, splitting and trimming. Hence, the cost of diamond saws and energy have become important input in terms of estimating the hourly areal slab productions (HASPs) from the standpoint of effective cost analyses, feasible and sustainable

The current situation and development trends in the biological degasification of coal are reviewed. It is shown that methane desorption is a consequence of rock mass destruction by activity of microorganisms and releasing bacterial metabolites. The influence of microorganisms on coal as a function of a prevailing microbial community and its variety, access of oxygen and nutritious substrates is observed

The influence of nitric, sulfuric and chlorohydric acids on the morphology, composition of elements, structural and chemical transformation of mineral surface and leaching of eudialyte concentrate is studied using a set of the modern analytical techniques. Specific features are revealed in the nature and degree of eudialyte decomposition under the influence of different acids. These features affect

Three influences on physical modeling results of unstable dynamic displacements along fault edges under triggered relaxation are considered. The fault filler is assumed to be quartz sand placed in-between moving tiff and rough plates. This quartz sand interlayer is subject to variation in compaction, to relaxation from stresses and to a burst air flow across the interlayer to simulate gas rush in the

The authors analyze the effect revealed at the Institute of Mining, SB RAS in the 1970s. This effect consists in a noticeable off-center displacement of the maximum normal pressure on the bottom of a conical pile when heaped. The new experimental data are presented. The stress-stress analysis of the pile between two parallel smooth plates is solved using a 3D discrete element method. The calculations

The influence of non-ionic compounds in combination with sodium oleate on the contrast behavior of flotation response of calcium minerals is investigated theoretically and experimentally. The flotation and adsorption analyses are carried out with monomineral fractions of calcite and scheelite, while the flotation process analysis is conducted with an ore material screened into size grades of -44 and

Specifications of domestic and foreign shearers are given. The problem is formulated for optimizing web width of a shearer by the maximum capacity criterion with regard to geological and technology factors. The analytical solution is obtained for the problem using the approximating linear functions of the sloughing factor and the web width. The influences of the optimal web width of shearer are analyzed

Layouts of reloading points in the cyclical-and-continuous technology for deep-level surface mining are analyzed. The innovative structure of a reloading point involving dump trucks drivethrough passing has been proposed; the structure will make it possible to increase reloading point productivity, cut the costs for rock mass extraction, and reduce the time of motor transport maneuvering. Dependence

The modeling procedure is developed to describe heat-exchange processes in outdoor summer storage piles of frozen coal produced in winter. This procedure takes into account thermophysical properties of coal and the pile bottom soil, pile structure, climatic factors and the presence of a heat-insulating coating over the pile. In terms of central Yakutia, it is shown that maximum transition of coal from

The geological information on coal reserves within fields of the Chertinskaya-Yuzhnaya and Chertinskaya-Koksovaya mines situated in the vicinity of an earthquake focus is given. Methane emission in roadways of the mines is determined, and the model diagram of methane concentrations before and after the earthquake is obtained. The earthquake load on coal seams is estimated.

High production rates and low operating costs highlight block caving as one of the favorable underground mining methods. However, the uncertainties involved in the material flow make it complicated to optimize the production schedule for such operations. In this paper, a stochastic mixed-integer linear optimization model is proposed in order to capture horizontal mixing that occurs among the draw columns