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Date submitted2021-03-05
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Date accepted2021-04-28
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Date published2021-09-20
Rational design justification of the tunnel boring shield executive body for the conditions of the mines of Saint Petersburg Metrostroy
The article discusses the features of running tunnels in difficult mining and geological conditions of the Saint Petersburg Metrostroy using modern tunnel boring shields of Herrenknecht company with hybrid executive bodies equipped with a incisors and rock cutters. The work of a hybrid executive body is analyzed when driving along a heterogeneous bottomhole massif consisting of Cambrian clay with limestone interlayers. Theoretical and experimental studies of vibroactive cones, a graphical representation of the dependence of the depth of their penetration on the axial force and axial force together with the applied shock load (the dependences of the penetration depth are interpreted as a linear dependence) have been carried out. An increase in the intensity of destruction of a heterogeneous bottomhole massif consisting of Cambrian clay and limestone interlayers using vibroactive rock-cutting tools (spiked roller) was theoretically and experimentally confirmed, while the growth of the penetration rate is determined depending on the number of their parameters. The design is considered, the principle of operation and the method of power calculation of a rotary executive body equipped with vibroactive cutters are described, on the basis of which a nomogram of the dependence of the torque and performance of the tunnel boring shield on the feed rate of the executive body to the bottom is built.
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Date submitted2020-05-12
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Date accepted2020-09-22
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Date published2020-11-24
Design features of coal mines ventilation using a room-and-pillar development system
- Authors:
- Sergey S. Kobylkin
- Alexander R. Kharisov
The safety of mining operations in coal mines for aerological factors depends on the quality of accepted and implemented ventilation design solutions. The current “Design Manual of coal mine ventilation” do not take into account the features of room-and-pillar development systems used in Russia. This increases the risk of explosions, fires, and gassing. The detailed study of foreign experience in designing ventilation for the considered development systems e of coal deposits allowed to formulate recommendations on the ventilation scheme organization for coal mines using a room-and-pillar development system and the procedure for ventilation during multi-entry gateroad development. Observations have shown that the use of the existing Russian procedure for airing mining sites with a room-and-pillar development system complicates the emergency rescue operations conduct. Low speeds and multidirectional air movement, difficult heat outflow, and the abandonment of coal pillars increase the risk of occurrence and late detection of endogenous fire. The results of numerical modeling have shown that the installation (parallel to the drifts) of ventilation structures in inter-chamber pillars will increase the reliability of ventilation by transferring the ventilation scheme from a complex diagonal to a complex parallel. It will also reduce the amount of air required for the mine site and the total aerodynamic drag. The research made it possible to formulate requirements for the design procedure for coal mines ventilation using a room-and-pillar development system, which consist in the order of working out blocks in the panel, and also the additional use of ventilation structures (light brattice clothes or blowing line brattice).
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Date submitted2019-01-03
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Date accepted2019-03-23
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Date published2019-06-25
Normalization of thermal mode of extended blind workings operating at high temperatures based on mobile mine air conditioners
Thermal working conditions in the deep mines of Donbass are the main deterrent to the development of coal mining in the region. Mining is carried out at the lower technical boundaries at a depth of almost 1,400 m with a temperature of rocks of 47.5-50.0 °C. The air temperature in the working faces significantly exceeds the permissible safety standards. The most severe climatic conditions are formed in the faces of blind development workings, where the air temperature is 38-42 °С. It is due to the adopted coal seam mining systems, the large remoteness of the working faces from the main air supply openings, the difficulty in providing blind workings with a calculated amount of air due to the lack of local ventilation fans of the required range. To ensure thermodynamic safety mine n.a. A.F.Zasyadko we accepted the development of a draft of a central cooling system with ground-based absorption refrigerating machines with a total capacity of 9 MW with the implementation of the three types of generation principle (generation of refrigeration, electrical and thermal energy). However, the long terms of design and construction and installation work necessitated the use of mobile air conditioners in blind development faces. The use of such air conditioners does not require significant capital expenditures, and the terms of their commissioning do not exceed several weeks. The use of a mobile air conditioner of the KPSh type with a cooling capacity of 130 kW made it possible to completely normalize the thermal working conditions at the bottom of the blind workings 2200 m long, carried out at a depth of 1220-1377 m at a temperature of host rocks 43.4-47.5 °С. It became possible due to the closest placement of the air conditioner to the face in combination with the use of a high-pressure local ventilation fan and ducts, which ensured the air flow produced by the calculated amount of air. The use of the air conditioner did not allow to fully normalize the thermal conditions along the entire length of the blind face but reduced the urgency of the problem of normalizing the thermal regime and ensured the commissioning of the clearing face.
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Date submitted2015-10-27
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Date accepted2015-12-14
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Date published2016-08-22
Studying the dependence of quality of coal fine briquettes on technological parameters of their production
- Authors:
- T. N. Aleksandrova
- A. V. Rasskazova
The study characterizes the role of coal in the fuel and energy balance of the Far East Region and points out the issue of losses of coal fines in the processes of coal mining, transportation and processing. To solve the problem of losses of coal fines, the mined coal is sorted into different size classes and fuel briquettes are produced from coal fines. Physical foundations are presented in short of briquetting solid combustible mineral resources. The dependences and variations of briquette compression strength limit are studied vs. charge humidity and briquetting pressure. Optimal parameters are retrieved for briquetting coal fines. The principal technological scheme is given of the process of briquette production. The developed technological solutions include sorting regular coal and briquetting coal fines, as well as the involvement of technogenic carbon-containing wastes from the hydrolysis production lines, plus residuals from oil refining.
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Date submitted2015-08-17
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Date accepted2015-10-25
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Date published2016-04-22
Ecological aspects of vehicle tunnels ventilation in the conditions of megalopolises
- Authors:
- S. G. Gendler
The characteristic of Russia and foreign vehicle tunnels are provided in paper and advantages of their placement in the conditions of the city are noted. It is shown that one of the main factors defining negative impact on environment in the period of tunnels driving is mine equipment, and at operation – vehicles. The analysis of essential differences of features of pollution of atmospheric air at construction of tunnels from its pollution at construction of buildings on a surface is given. The examples illustrating levels of negative impact of the upcast ventilation shaft airflow on atmospheric air are given and the ventilation schemes reducing this influence are offered. It is shown that during operation of road tunnels of pollution of the air environment can extend on considerable distances from tunnel portals. Numerical calculations of concentration of carbon oxides and nitrogen during removal of the upcast ventilation shaft airflow through portals and through the mines built near them are executed. Technical solutions on purifications of tunnel air by means of electrostatic filters are described.
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Date submitted2015-08-02
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Date accepted2015-10-04
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Date published2016-04-22
Development of innovative technologies of dedusting in mining and advance coal mine faces
- Authors:
- G. I. Korshunov
- S. B. Romanchenko
The article describes the results of the implementation of investment projects in the field of complex dedusting implemented in major coal producing companies in Russia. Experimental study of the processes reduce the levels of dust in the workplace in the application of modern systems of irrigation and aspiration systems. The factors that determine the mass and composition of particulate airborne dust at various ways of dust suppression. The results of the analysis of the laser dispersed composition of particles removed from the air of the working area
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Date submitted2010-07-12
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Date accepted2010-09-14
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Date published2011-03-21
Principles of an automatic control system of ventilation creation the kuznetsovsky railway tunnel
- Authors:
- S. G. Gendler
- V. A. Pleskunov
For effective ventilation Kuznetsovsky railway tunnel the longitudinal scheme of ventilation based on use of jet fans is offered. It is shown that use of the offered scheme of ventilation at influence of natural draft and piston effect of trains is impossible without an automatic control system of ventilation (ACSV). The principles of work ACSV taking into consideration natural and operational factors are proved.
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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 submitted2009-08-13
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Date accepted2009-10-17
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Date published2010-02-01
Selection of optimal scheme of a reclamation of mining damp of the open-cast «Mejdyrechensky»
- Authors:
- I. R. Levchuk
The paper deal with the problem of finding the optimal way of land reclamation for opencast mining company «Mejdurechye», which nowadays is one of the leading companies in Russia in it area. Therefore the question of land reclamation is one of the major issues to adress for this organisation. During the reaserch samples of antropogenic massifs were taken and analyised, which helped to work out a complite plan of restoration. Besides the scheme, a brief review of disadvantages of the suggested plan is available as well as their removal. Special attention is paid to the necessity of biologikal reclaimation because of the low speed of flora recovery.