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Date submitted2023-12-15
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Date accepted2024-06-13
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Date published2025-02-25
Development of equipment and improvement of technology for inertial thickening of backfill hydraulic mixtures at the final stages of transportation
The results of the study of the functioning of the developed thickening equipment as part of the stowing complex for the formation of a flow of high-concentration hydromixture are presented. To explain the operation of the hydrotransport system of the stowing complex, equipped with a thickener of the developed design, its basic diagram is presented. A mathematical model has been created that describes the mechanism of inertial sedimentation of a solid component of a hydraulic mixture in a working chamber equipped with hydrodynamic profiles. Interaction with the profile leads to flow stratification due to a change in the trajectory of movement and a decrease in speed. The interval of rational velocity of primary pulp entering the input of the working chamber of the inertial thickener is substantiated. The synthesis of solutions of the thickening process model is performed in the COMSOL Multiphysics and Ansys Fluent programs. This made it possible to eliminate physical contradictions in the operation of the equipment and justify the overall dimensions of its main elements, ensuring the implementation of the mechanism of inertial sedimentation of the slurry. It was found that the concentration of the thickened flow at the outlet branch pipe of the thickener working chamber is determined by the level of the primary hydraulic fluid velocity, the characteristic length of the section of interaction with the deflecting profile, and the ratio of the flow and attack angles. A nomogram of the dynamics of the change in the hydraulic fluid concentration in the section of the outlet branch pipe depending on the ratios of the overall dimensions of the deflecting profile of the working chamber was compiled. The results of the study allowed formulating recommendations for selecting the dimensions of the thickener's deflecting hydrodynamic profile to form a flow of hydraulic mixture with a concentration of about 50 % by weight. The developed equipment can be used in a stowage complex and will increase the range of supply of the stowage mixture. This is due to the fact that a flow of primary slurry with a low concentration, due to lower pressure losses, can be moved in a pipeline system over a greater distance than a flow with a high filler content. The use of a thickener at the final stage of transportation is intended to increase the concentration of the hydraulic mixture immediately before production.
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Date submitted2021-12-15
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Date accepted2022-09-12
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Date published2023-08-28
Substantiation and selection of the design parameters of the hydroficated equipment complex for obtaining backfill mixtures from current enrichment tailings
The issue of the influence of the concentration of the solid phase on the reduction of energy costs and specific energy consumption during pulp transportation is considered. The procedure for preparing slurry from the current enrichment tailings is shown. A scheme is given and the operation of a hydroficated unit for thickening and hydraulic transport of backfill mixtures is described. A diagram of the movement of solid particles in one of the units of the complex – a lamellar thickener is shown. The summary table shows the main design parameters and characteristics of the lamellar thickener. A general view of the laboratory setup used for experimental studies with slurry at various concentrations is given. An example of calculating productivity, density and specific load is presented. The dependence of the shear stress on the velocity gradient was determined for various pulp concentrations. Experimental studies of the process of thickening the production of slurry from the current enrichment tailings have been carried out. It was found that the geometric dimensions of the thickener depend on the concentration of the solid phase in the transported mixture. It is concluded that the flow rate of the slurry and the head loss are functions of the rheological characteristics of the viscoplastic slurry and can be calculated from the derived calculated dependencies.
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Date submitted2021-07-05
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Date accepted2022-01-24
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Date published2022-04-29
Ensuring the excavation workings stability when developing excavation sites of flat-lying coal seams by three workings
- Authors:
- Oleg I. Kazanin
- Andrei A. Ilinets
On the basis of analysis of mining plans and field studies at mines of JSC SUEK-Kuzbass, it is shown that in conditions of increasing the size of excavation columns during the development of flat-lying coal seams the stress-strain state of the rock mass along the workings length changes significantly. The necessity of predicting the stress-strain state at the design stage of the workings timbering standards, as well as subsequent monitoring of the workings roof state and its changes in the mining operations using video endoscopes, is noted. The results of numerical studies of the stress-strain state of the rock mass during the development of excavation sites by three workings for various combinations of width of the pillars between the workings for mining-geological and mining-technical conditions of the “Taldinskaya-Zapadnaya-2” mine are provided. The stresses in the vicinity of the three workings are compared with the values obtained during the development of the excavation sites by double drift. A set of recommendations on the choice of the location of the workings, the width of pillars, timbering standards that ensure the stable condition of the workings throughout the entire service life at the minimal losses of coal in the pillars is presented.
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Date submitted2019-07-21
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Date accepted2019-09-20
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Date published2020-02-25
Assessment of operational reliability of quarry excavator-dump truck complexes
- Authors:
- V. M. Kurganov
- M. V. Gryaznov
- S. V. Kolobanov
The method proposed in the article is based on the mathematical apparatus for quantitative assessment of the reliability of majority schemes of structural redundancy of transport processes, which provide the availability and usage of several backup delivery channels in the transport process in case of any malfunction. The principle of multi-channel haulage is commonly used in quarries for transportation of overburden and minerals from benches by dump trucks, when excavators and dump trucks performing cyclic operations function as a single excavator-dump truck complex. This pattern of work significantly increases the likelihood of fulfilling the daily plan for transporting rock mass due to the redistribution of dump trucks between mining and overburden excavators in the event of failure of one or more units of mining and handling equipment. The reliability of excavator-dump truck complexes is assessed in three stages: initial data collection for mathematical modeling of excavator-dump truck complex performance; solving the problem of optimizing the distribution of dump trucks between excavators, ensuring maximum productivity of the excavator-dump truck complex; assessment of the reliability of its work depending on the probability of fulfilling the daily plan for the transportation of rock mass. The proposed method is implemented as part of a computer program and makes it possible to automate the operational management of the process of transporting rock mass in a quarry using a mobile application. The developed guidelines can be used for any quarries with automobile transport, regardless of the type of mineral extracted, the mining method, the loading pattern, the capacity of the excavation and loading equipment fleet, and the capacity of operated dump trucks.
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Date submitted2017-12-28
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Date accepted2018-03-03
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Date published2018-06-22
Special features of a structure of technical operations for peat excavation with stage dewatering
- Authors:
- E. A. Kremcheev
A method of development of a technology of peat extraction for intensifying of dewatering which involves drying of peat raw materials in thick layers with a layer-by-layer harvesting into large-sized roll with further delivery to the field storage unit of the enlarged sizes is presented in the paper. Throughout the year storage raw materials may be transported to the customer or to the shopfloor for further processing. Considering dimension and mass characteristics, a crumbed peat of various moisture capacity is a major type of products to be of high demand. On the basis of the results of scientific studies regarding gravity dewatering of peat and its drying in field environment, the ways of intensifying of field dewatering of peat for extraction at shallow-peat lands and fine-limit fields are proposed. The presented results of the experimental performance of a technology of peat drying in thick layers with a layer-by-layer harvesting indicate an increase of seasonal harvesting and a decrease of the influence of unfavorable meteorological factors on the stability of the extraction process. Performed investigations allowed to develop a structure of technical operations for peat excavation with the stage dewatering in spreading and intermediate storage units providing rational state of the extraction process regarding a complex of technical factors. A suggested scheme of a process area for a primary and secondary period of deposit exploitation by a technology of peat excavation is considered.
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Date submitted2017-11-22
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Date accepted2018-01-04
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Date published2018-04-24
Justification of a methodical approach of aerologic evaluation of methane hazard in development workings at mines of Vietnam
- Authors:
- V. V. Smirnyakov
- Nguen Min' Fen
The methods of evaluation of the aerological conditions to be performed for the purpose of normalization of mining conditions are provided in the present review; the location of possible accumulations of explosive gases during the drift of the development workings are taken into account. To increase the safety of the development working regarding the gas factor, a complex evaluation of a working was developed with respect to the dynamics of methane emission and air coursing along the working which is strongly affected by the character of the leakages from the ventilation ducting. Thereby, there occurs a necessity of the enhancement of a methodical approach of calculation of ventilation of a working which consists in taking into consideration a total aerodynamic resistance of the booster fan including the local resistances of the zones of the working. An integer simulation of the gas-air flows realized on the basis of a software package FLowVision allows to evaluate a change in the methane concentration in the zones of local accumulations.
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Date submitted2017-08-25
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Date accepted2017-11-17
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Date published2018-02-22
Improved estimation of open pit excavator capacity
- Authors:
- S. N. Zharikov
The paper addresses issues related to estimation of operational time for open pit excavators during truck loading operations. The author analyzes the method of annual capacity estimation and highlights disagreements in different ways of operational time logging. Recommendations are offered concerning estimation of excavator capacity taking into account its repair cycle. The paper contains an analysis of the cyclical nature of various types of maintenance in the interval between capital repairs as a function of operational time. Guidelines are proposed that allow to calculate annual production days of the excavator with regards to the repair cycle and adjusted utilization coefficient throughout the shift. It has been established that decreasing the coefficient of excavator utilization throughout the shift and more precise logging of annual work days lead to a slower decrease in estimated machine capacity than the one described in the reference literature. According to the suggested method, estimated excavator capacity is more than 23 % higher than the value stated in the reference literature.
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Date submitted2016-09-15
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Date accepted2016-11-07
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Date published2017-02-22
Open-pit mining of lignin waste storage
- Authors:
- A. V. Mikhailov
The purpose of this paper is to develop performance criteria for fleet selection in surface mining of lignin as a raw material for factory-made fuel. The East Siberian Biotechnical Plant (ESBP) proposes to close the Lignin Waste Storage (LWS) at Tulun, Irkutsk Region of Russia. The LWS is a 9.6 ha facility used for the long-term storage of hydrolysis lignin and some fly ash. The project provided whole-year open-pit mining of lignin storage with one mining ledge within 3 years. Productivity – 1500 t/day or 447 000 t/year. Excavated lignin will be stockpile on the Pellet Plant territory for later processing. Part of this closure effort would involve constructing an artificial reservoir on the place of LWS. The objectives of this project were as follows: determine equipment needs and develop optimal procedures for the lignin excavation and transportation. Lignin moving may include site preparation, excavation, transportation and road surfacing. Lignin excavation is conduct by using techniques similar to those used for open-pit mining of peat. For this project, the excavator is the most important piece of equipment required for lignin removal and handling. The mining process consist of excavating the lignin (using Kraneks ЕК-270LC) and hauling it to pellet plant via six off-road tractors&semitrailers (John Deere 7730& ISON-8520).
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Date submitted2014-12-30
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Date accepted2015-02-03
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Date published2015-12-25
Open mining technique for unconventional mineral deposits
- Authors:
- G. A. Kholodnyakov
- K. R. Argimbaev
Nowadays the majority of deposits are successfully exploiting by mining enterprises with the help of traditional excavation and loading equipment. Typically, metals, construction materials, etc. are mined and extracted on these deposits, but modern society is progressing and producing new requirements to metals properties for creating a new type of equipment. The metals with new properties are located in unconventional areas: either in technogenic deposits (overburden dumps, tailings, etc.) or in hard-to-get natural formations. Technogenic mines, being a tailing of Kachkanarsky mining and processing plant, are referred to such unique deposits, which have expensive metals (scandium, gallium, strontium, titanium), as well as the natural deposit – rhenium deposit, located in the crater of an active volcano. Potentialities of open mining in the largest rhenium deposit with complex environmental occurrence have been analyzed in the paper. Temperature measurement results of adjacent strata and a temperature scheme of the host rocks on a separate site and the entire field have been presented. An open mining technique for a primary mining area as well as perspective methods of rock preparation for excavation, applicable to this particular deposit, has been considered.
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Date submitted2014-10-08
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Date accepted2014-12-11
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Date published2015-08-25
Modeling of geomechanical processes in ore mass using physically nonlinear model
- Authors:
- A. G. Protosenya
The aim of the article is to develop a method of forecasting the state of stress of the ore mass around excavations for ores of weak and medium strength. The paper presents experimental studies on the deformation of ore samples of low and medium strength in the forging equipment in conditions of volume stress state. A physically nonlinear model is used to describe the deformation process of ore mass. The study of the stress state of physically nonlinear ore mass around excavations of round and valuated cross-sections is performed. Values of coefficients of tangential stress concentrations on excavation contour are found for different types of ore. Solutions to physically nonlinear problems in preparatory excavations in the development of the Yakovlevskiy deposit of rich iron ore using a slicing method are considered. Methods for forecasting the stress state in rock mass around mine excavations can be used to assess their stability in the mining of ore of low and medium strength at the Yakovlevskiy iron ore deposit and in the rock and soil masses.
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Date submitted2013-07-05
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Date accepted2013-09-23
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Date published2014-03-17
Increase of stability of mine workings in the permafrost zone
- Authors:
- A. F. Galkin
Some experimental results of increase of stability of mine workings are presented in this article. The investigated mine workings are located in the permafrost conditions and the increasing of stability is achieved by insulation. Problems of thermal protection of frozen breeds are considered at high temperatures of air in mine workings.
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Date submitted2013-07-07
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Date accepted2013-09-17
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Date published2014-03-17
Ways of improving waste disposal in the workings of salt mines
- Authors:
- O. V. Kovalev
- S. P. Mozer
Address the major aspects of waste disposal in underground space. Are key problems of isolation of wastes in underground salt deposits? Proposed waste disposal technology, based on the use of waste for immobilization of natural mineral salts.
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Date submitted2009-10-18
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Date accepted2009-12-17
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Date published2010-09-22
Reuse of development workings as an element of providing the effective coal output
- Authors:
- M. A. Ilyashov
The article contains the results of application in a coal mine of a combined way for protection and support of development workings. This method combines a frame support, anchors and a cast support strip erected behind the longwale. The geomechanical substantiation of technological parameters, regulations and the field for efficient use of this method are given. Its introduction has allowed to increase the loads on longwale and to lower labour content and expenses for maintenance of butt entries.
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Date submitted2009-10-14
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Date accepted2009-12-03
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Date published2010-09-22
Some geomechanical aspects in the development of calculation methods of rock pressure in permanent mine workings
- Authors:
- A. M. Kozel
The paper deals with the particular features of the stress-strain state and mechanical condition of the rocks surrounding the permanent mine workings; they should be taken into account in the development and updating of standards and calculation methods to ensure the stability of these workings.
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Date submitted2009-09-06
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Date accepted2009-11-14
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Date published2010-06-25
The estimation of mass velocities in a layered roof and dividing pillars of the mining system in the time of influence of shock stress waves
- Authors:
- V. V. Karpenko
- G. A. Kolton
The mass velocity diagrams transformation in the layered border zone of the mining system in the time of tension explosion waves influence is considered. The explosion wave front is suggested to be parallel to the proximate handing roof environs discontinuity. Under the admitted assumption the mass velocity epures transformation is investigated in the layered roof stone of the mining system and in the dividing pillar.
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Date submitted2009-09-07
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Date accepted2009-11-17
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Date published2010-06-25
The transformation of zone of potentially dangerous accumulative wrecks in a layeked mining roof when combined effect of the rock pressure and shock stress waves
- Authors:
- V. V. Karpenko
The transformation of potentially dangerous zone of wrecks accumulation in the layeredroof of the mining system is considered, in the time of combined action of geostatic pressure and tension shok wave. The explosion wave front is suggested to be parallel to the proximate handing roof environs discontinuity. Under this condition in the article is considered the influence of levels of critical stress and the depth of opening location on the change of implicitly dangerous zone of faults accumulation in the layers of the root stone.
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Date submitted2009-07-25
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Date accepted2009-09-09
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Date published2010-04-22
The use of data on stress-strain state of rock mass in solutions of mining-and-technical tasks on the example of the Tishin ore mine
The Permion State Technical University and ASE «VNIItsvetmet» have carried out in situ measurements of stress-strain state at the Tishinsky lead-zinc ore deposit. Measurements and interpretation of deformations and stresses caused by excavation were used. Complex of researches made it possible to solve some important problems for safeguarding effective and secure ore production ore on deep level.
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Date submitted2009-07-24
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Date accepted2009-09-27
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Date published2010-04-22
Influence of geomechanical processes in rock mass on the selection of parameters of technological schemes for flat seams mining at the Leninsk-Kuznetsk coal deposit
- Authors:
- E. P. Yutiaev
The article deals with the aspects concerning the influence of geomechanical processes in rock mass on the selection of parameters of technological schemes for flat coal seams mining. Based on the analysis of experience gained under similar conditions at coal mines of the advanced national and foreign countries, the promising trends in the research work and development projects for the SUEK-Kuzbass Co.were suggested.
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Date submitted2009-07-29
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Date accepted2009-09-15
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Date published2010-04-22
Preconditions for application of supports of different types in productive workings of low-thick gently-pitching deposits in tectonically stressed massif (for conditions of the Karnasurt ore mine)
- Authors:
- A. V. Lovchikov
- A. V. Matytsyn
The paper presents the data on the mining-geological conditions for mining and types of stope supports applied at the Karnasurt Mine, the Lovozersky rare-metal deposit. The peculiar feature of mining conditions is the presence of high subhorizontal tectonic stresses in the rock masses, which make the stope roofs more stable, allowing application of non-reinforced types of support.
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Date submitted2009-07-19
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Date accepted2009-09-11
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Date published2010-04-22
Calculation of supports of parallel workings divided with yieldable pillars at anthracite seams
The article presents the methods for calculation of supports of parallel workings divided with yieldable pillars at anthracite seams. Consideration is given to the development of experimental data card for protection and maintenance of paired conveyor entries with using the steelpolymer anchor supports.
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Date submitted1951-07-30
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Date accepted1951-09-09
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Date published1952-03-26
Forecast of water breakthroughs from the soil of mine workings
- Authors:
- A. I. Morozov
The development of brown coal deposits in the Moscow Basin is associated with serious difficulties caused by the instability of the host rocks and their high water content. Water content is the cause of peculiar phenomena called breakthroughs. A breakthrough is the release of water or quicksand into mine workings. According to their location and origin, breakthroughs can be divided into two types: 1) breakthroughs from the soil and 2) breakthroughs from the roof. The nature and mechanics of the phenomenon of breakthroughs from the soil and roof are different. A breakthrough from the roof can occur in all cases when, during a roof collapse in a development working or a stope, the above-coal aquifer falls into the collapse zone, regardless of whether it is confined or unconfined. The presence of confined water increases the intensity of the breakthrough and makes it more dangerous in its consequences. For a breakthrough from the floor of a mine working to occur, the presence of a subcoal aquifer is necessary, but still not a sufficient condition. A breakthrough can occur only when the subcoal waters have a pressure that exceeds the level of the workings' soil and are separated from the latter by a low-power impermeable layer. The mechanism of a breakthrough from the soil is reduced to the destruction of the subcoal clay layer that blocks the access of the subcoal aquifer waters to the preparatory or treatment workings. The main active force that destroys the thickness of subcoal clays is the hydrostatic pressure of the subcoal waters.
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Date submitted1950-07-22
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Date accepted1950-09-14
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Date published1951-04-30
On the theory of icing of mine workings during their ventilation
- Authors:
- A. S. Ter-Pogosyan
During summer ventilation of some workings with low temperatures (acquired, for example, during the winter cooling period), warm atmospheric air, getting into the working, enters into heat exchange with its walls and, cooling, becomes saturated. Therefore, condensed moisture falls on the walls of the working. Its fallout begins from the place where the air flow temperature becomes equal to the saturation temperature. From the same place of the working, where the flow temperature reaches 0°, icing of moisture occurs, which complicates the operation of the working. It is necessary to calculate: 1) icing and condensation thresholds, 2) the thickness of the icing layer, the distribution of temperature along the working as a function of time, air flow velocity, transverse dimensions of the working, temperature and humidity of the atmospheric air.
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Date submitted1948-07-11
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Date accepted1948-09-13
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Date published1949-11-04
On the influence of the cost of transport on the floor crosscuts on the most advantageous dimensions of the mine field
- Authors:
- O. B. Bokii
This article is devoted to the assessment of the impact of the cost of hauling minerals along floor crosscuts on the most advantageous longwall dimensions of the mine field of a vertical shaft opening a suite of steeply dipping seams, determined by the method of L. D. Shevyakov. The cost of hauling minerals along crosscuts during the development of a suite of steeply dipping seams by a vertical shaft with floor crosscuts increases with the increase in the number of floors in the mine field and decreases the most advantageous number of floors against the values given by L. D. Shevyakov's formulas derived without taking this factor into account. In exceptional cases (location of the mine outside the suite with a small angle of dip of the seams), the number of floors determined without taking into account the cost of transport along floor crosscuts may exceed their most advantageous number by 50% or more.