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The expediency of allowance for the links in the georesource-open pit-preparation plant chains as an integral information, technology and management space is considered. The methodical approaches to improvement of useful qualities of coal, in the first turn, its ash content graded as a rank of components are substantiated. In terms of the Elga deposit in South Yakutia, potentiality of increase in completeness and quality of coal extraction based on the studies into structure and contact zones of seams is illustrated. The schemes are proposed for ash content control in coal mining through extraction of dirt and high-ash interbeds of various thickness. The process charts for mining thin coal and dirt interbeds are proposed. The recommendations are provided for development of coal seams composed of bands of different ash content and washability.

In order to evaluate water inrush risk from the deep coal floor by mining above the confined aquifer in Yongxia mining area of Henan Province, the structural complexity of the study area was partitioned by fractal dimension method. Moreover, the water inrush coefficient was calculated, and quantization partition was also carried out using the distribution law of the water inrush coefficient contour. Comparing the results of the two methods, it is found that the structural complex area and the water inrush danger zone have good coincidence in parts of study area, which increases the estimating reliability of the water inrush risk. At last, water inrush risk. The research results have an important reference value for realizing safe and efficient mining of the second level coal seams.

The results of the experimental studies into formation conditions of gas dispersion during electrolytic flotation are presented. The facing factors of electrolytic bubbling are considered. The influence exerted by the electrolysis process parameters and electrolytic compositions of water solutions on the dispersion state and gas content of electrolysis solutions is analyzed. The effects on the electrical state of the bubbles during electrolysis are studied.

Based on the relationship between collectability of flotation agent to flow thickness of its physically attached species desorbed from mineral surface to gas-liquid interface, the backbone of the method for selecting structure and composition of the collecting agent molecule is developed. The method application discloses effects exerted by the structure and composition of hydrocarbon fragment in the collecting agent molecule on the useful component recovery and concentration quality. In terms of the known colleting agents (branched carboxylic acids, N-acidilate amino acids and oxyacids, as well as nonsulphide flotation regulating agents-oxyethylated aliphatic alcohols), the reasons of the selections as collecting and regulating agents in flotation of apatite, quarts, hematite and magnetite are shown. Influence of some structural features of hydrocarbon radical on collecting ability of an agent is found, namely, length and arrangement of side chains, distance between carboxylic and amide groups in N-acidilate amine acids, number of oxyethyl groups and their arrangement in hydrocarbon g\fragment of alcohols or oxyacid.

The research results on gravity concentration of the Shalkiya deposit lead-zinc ore are presented. Using the float-and-sin analysis data, the Henry-Reinhard-type washability curves are calculated and plotted for separation size grade 40-8 mm. The separation density required for recovery of light fraction at minimum possible loss of lead and zinc, as well as the the gravity washability indexes are determined. It is found that the overhead product of the gravity concentration of coarse ore is tailings containing silicon, calcite and carbon black dioxides. The loss of lead and zinc is minor. Processing of coarse crushed ore should be carried out in heavy medium.

The breakage mechanism of flocs in mineral suspensions under shearing is considered. The relationship of limiting dynamic shear stress, diameter of particles and flocculant consumption is determined. It is calculated that for the floc structure to be preserved, it is required that the maximum allowable flow velocity of suspensions in pipelines 0.2-0.6 m in diameter is on average 1.8, 2.6 and 3.9 m/s at flocculant consumptions of 50, 100 and 200 g/t, respectively. The inverse problem on minimum allowable diameters of pipelines is solved. At the suspension flow rates of 100-1000 m³/h and flocculant consumption of 50-200 g/t, these values range from 0.1 to 0.4 m. The increase in the flocculant consumption by 2 times, all other things being equal, conditions reduction in the allowable diameter of pipelines by 20%.

The research results are presented for dressability of quartzites from the Garga quartzite region of the East Sayan. From the detailed analysis of the structure, texture, mineral and fluid inclusions in the chemical constitution, bright veined quartzites and coaly veined quartzites were distinguished in the Urda-Gargan block. Both kinds are readily dressed up quartz concentrates of deep concentration. The fist quartzite kind can be used in manufacturing of transparent optical quartz glass, whereas the second variety is a promising feedstock for carbothermal production of silicon.

The control of flotation processes has always been an important research subject. Many experts and scholars have carried out extensive research to avoid the problems encountered when operating in a manual mode. By combining long-term worker tracking experiments and observations of froth appearance characteristics in a gold-antimony flotation plant, a reagent dosage hybrid control strategy for the antimony flotation process is proposed in this work. This strategy consists of two parts: reagent dosage tracking control based on a froth size probability density function (PDF) and reagent dosage compensation control based on a distributed-machine vision predictive model. The proposed method was tested on a gold-antimony flotation process, and it improved tailings qualification rate to 96.67%, and reduced the tailings standard deviation. This method also efficiently accounts for the influence of disturbances on the flotation system and improves the stability and effectiveness of the flotation system.

In this paper, the influence of alkali on the flocculation of starch on fine hematite was investigated through a series of tests, like turbidities, paste titration, adsorption, conductance, scanning electron microscope (SEM) measurement, and Fourier transforms infrared spectroscopic analysis (FTIR) as well. The results pointed out that alkali concentration has a strong influence on physicochemical changes of starch granules, inducing different adsorption densities on mineral surfaces. A maximum amount of adsorption density (10.5 mg/g hematite) on minerals particles was harvested for the starch digested with sodium hydroxide at a concentration of 0.4 N/g starch. It is worthy to note that starch is not fully digested in the presence of alkali at a concentration of less than 0.4 N/g starch. Higher concentration of hydroxide ions, however, tends to obtain less adsorption density of starch on hematite because too small size/weight remnants in the starch gel have inverse effects on adsorption capacity.

The article substantiates the retrofit method for two-stage axial flow fans including an impeller and a flow straightener in each stage. In this method, the two-stage rotor is replaced by a high-rate one-stage rotor within the inlet guide vanes-impeller-flow straightener circuit. As a result, the air flow at the impeller input is uniform per standard, the operational life of the rotor bearing assembly is extended while the rotor mass is largely reduced. The procedure is developed for design and selection of aerodynamic and structural parameters of the remodel axial mine fans. The procedure takes into account the influence of the variable frequency drive and gyroscopic moment of the impeller, as well as the rigidity of the bearing assemblies and ratio of mass-inertia properties of the rotor, which allows determination of critical rotor speeds at early stage of design.