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Date submitted2022-05-17
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Date accepted2022-09-06
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Date published2022-11-03
Methodological substantiation of the choice for optimal modes of equipment operation during the stage-wise concentrate removal in iron ores beneficiation
- Authors:
- Alexandr S. Opalev
- Svetlana A. Alekseeva
The urgent task of improving the quality of iron ore concentrates was studied. We propose to use the stage-wise removal of the concentrate by combining fine screening, regrinding, and magnetic-gravity separation. Exemplified by magnetite ore from the Stoilensky GOK, a scientific and methodological approach to the search for optimal separation parameters and modes was substantiated. It includes several stages: studying the particle size distribution and release of useful components in the feed product to select classification parameters; a series of experiments on grinding oversize products to diverse sizes; beneficiation of the obtained products by MG separation. To select the optimal parameters of ore preparation, an analysis of the beneficiation efficiency was used, which is calculated according to the Hancock – Luyken criterion. The results of the research are experimental dependences that connect the process parameters of beneficiation with those of fine vibratory screening. For the studied ferruginous quartzite ore processed at the Stoilensky GOK, the obtained dependences can be described by a second-order polynomial with a high accuracy of approximation. The best performance is achieved with a particle size of 0.1 mm: Fe tot content in the concentrate is 69.7 %, recovery is 85 %, classification efficiency is 80.4 %. The top size of the product in this case is 0.076 mm, which corresponds to 70-73 % grinding size of –0.045 class.
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Date submitted2022-06-02
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Date accepted2022-07-21
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Date published2022-10-05
Substantiation of the optimal performance parameters for a quarry during the stage-wise development of steeply dipping ore deposits
- Authors:
- Sergey I. Fomin
- Maxim P. Ovsyannikov
The use of stage-wise schemes in the development of deep quarries is one of the ways to increase the economic efficiency of mining a deposit and determining the optimal stage parameters remains an urgent task. Such parameters are stage depth, bench height, block length, etc. However, there is a wide range of values for these parameters. Therefore, to select the optimal values and evaluate the effectiveness of design solutions, it is advisable to use the net present value, which is an international notion. As a result of the analysis of data on deposits, a large number of variable indicators can be identified that presumably affect the efficiency of mining. The article proposes to divide all parameters of the quarry mining into two types: mine engineering and economic. The importance of each of them is determined by the measure of influence on the net present value. Thus, to assess the measure of influence of mining indicators, the average values of each of them are taken, and as a result of the alternating change of one parameter under study, the measure of its influence on the discounted income received is estimated. The results of the analysis of relevant factors, their evaluation and comparative analysis are important indicators that significantly affect the design decisions made and the effectiveness of the investment project.
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Date submitted2021-05-31
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Date accepted2022-03-24
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Date published2022-07-13
Mathematical model of linear and non-linear proppant concentration increase during hydraulic fracturing – a solution for sequential injection of a number of proppant types
It is known that much of the technology aimed at intensifying fluid inflow by means of hydraulic fracturing involves the use of proppant. In order to transport and position grains in the fracture, a uniform supply of proppant with a given concentration into the fracturing fluid is ensured. The aim of the operation is to eliminate the occurrence of distortions in the injection program of proppant HF. A mathematically accurate linear increase of concentration under given conditions is possible only if the transient concentration is correctly defined. The proposed approach allows to correctly form a proppant HF work program for both linear and non-linear increase in proppant concentration. The scientific novelty of the work lies in application of a new mathematical model for direct calculation of injection program parameters, previously determined by trial and error method. A mathematical model of linear and non-linear increase of proppant concentration during HF was developed. For the first time, an analytical solution is presented that allows direct calculation of parameters of the main HF stages, including transient concentrations for given masses of the various types of proppant. The application of the mathematical model in formation of a treatment plan allows maintaining correct proppant mass distribution by fractions, which facilitates implementation of information and analytical systems, data transfer directly from a work program into databases. It is suggested to improve spreadsheet forms used in production, which would allow applying mathematical model of work program formation at each HF process without additional labour costs. The obtained mathematical model can be used to improve the software applied in the design, modelling and engineering support of HF processes.
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Date submitted2021-03-18
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Date accepted2021-11-30
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Date published2021-12-27
Deformations assessment during subway escalator tunnels construction by the method of artificial freezing of soil for the stage of ice wall formation
- Authors:
- Evgenii M. Volokhov
- Diana Z. Mukminova
The work is devoted to the study of the processes of displacement and deformation of the surface during the escalator tunnels construction of the subway by the method of artificial freezing of soils. The features of the construction and freezing technology, the rocks characteristics in which the escalator tunnels made are considered. The data of specially organized, full-scale surveying observations of deformations on the earth surface are presented. The main factors influencing deformation processes in the frozen strata of a layered inhomogeneous rock mass with inclined tunneling are determined, the complexity of the predictive task and the need to simplify the design scheme are shown. The work is focused on the assessment of the least studied geomechanical processes of soil heaving-uplifts and deformations during the periods of active and passive freezing stages. When studying the displacements processes of the earth surface and rock mass, the finite element method and analysis of the obtained data using field observations of displacements were used. A simplified calculation scheme is proposed for modeling, which allows taking into account the uneven influence of frozen rocks of an inhomogeneous layered rock mass with a large inclined tunneling. The satisfactory convergence of the data of field surveying observations on the earth surface and the results of modeling geomechanical processes for the period of active and passive freezing stages is shown. The proposed calculation scheme is recommended for the prediction of deformation at the stages of underground construction, characterized by the development of the most dangerous tensile deformations of buildings and structures on the surface.
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Date submitted2020-05-16
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Date accepted2021-03-02
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Date published2021-04-26
Study of drive currents for lifting bridge cranes of metallurgical enterprises for early diagnosis of load excess weight
The article discusses an approach based on the analysis of the drive motor currents to create an additional means of protection against emergency situations during the operation of bridge cranes associated with lifting a load with a mass exceeding the permissible one . A mathematical model of an overhead crane drive is described, as well as the results of computer simulation. It is shown that in the process of lifting up, before the stage of lifting the load, the stator current of the drive electric motor does not depend of the load mass, but when the load is detached, already for several periods of the mains voltage after the rope is pulled, when the mass of the load is exceeded, a measurable excess of the amplitude value of the current is recorded. This pattern has been confirmed for a number of cranes of various lifting capacities used at metallurgical enterprises. The possibility of diagnosing excess weight of the lifted load with a higher speed than existing mechanical methods of overload control is demonstrated, at the same time it is not required to make changes to the structural elements of overhead cranes.
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Date submitted2019-04-30
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Date accepted2019-07-16
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Date published2019-10-23
Salt Rock Deformation under Bulk Multiple-Stage Loading
- Authors:
- I. L. Pankov
- I. A. Morozov
The paper presents experimental justification of the possibility to use bulk multiple-stage loading to study the process of salt rock deformation in the laboratory conditions. Results of comparative tests between bulk multiple- stage and single-stage loading of salt rock samples are demonstrated. The paper contains results of research on the rate of lateral pressure and its impact on strength limit and residual strength limit of sylvinite, estimated using single- stage and multiple-stage methods. Research results demonstrate how the rate of lateral pressure impacts dilatancy boundary of salt rocks. Analysis of how the loading method influences certificate parameters of Mohr-Coulomb strength of sylvinite has been carried out. The dynamics of elastic modulus in the process of salt rock deformation is analyzed depending on the rate of lateralpressure. It is demonstrated how the method of multiple-stage loading adequately reflects the processes of salt rock de- formation and decomposition, and facilitates not only lowering impact of sample’s inner structure heterogeneities on the experimental results, but also significant reduction in the required amount of rock material.
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Date submitted2018-09-04
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Date accepted2018-11-18
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Date published2019-02-22
Operation experience of centrifugal single-stage pumps in «ALROSA» Joint Stock Company
- Authors:
- N. P. Ovchinnikov
When mining diamond-bearing raw materials and further extracting diamonds from it in the joint-stock company ALROSA, which is a city-forming enterprise in the north-east of the Russian Federation, various pumping equipment is used, in particular, centrifugal single-stage pumps. In the present work, it is noted that the least reliable in terms of absence of failures of centrifugal single-stage pumps used in the joint-stock company ALROSA are the impellers, seals and bearing assemblies. Using linear correlation and regression analysis, it was found that the durability of the seals and bearing assemblies of the investigated pumps largely depends on the durability of their impellers. In the course of research, it was found that unbalancing the pump rotor due to excessive hydroabrasive wear of the impeller also leads to deformation and fracture of the shaft. In general, residual deformations and destructions are characteristic of the shafts of domestic pulp pumps of GrAT, GrT and Gr types. The most loaded sections of shafts of centrifugal single-stage pumps are installed. The most effective from the point of view of application among the pulp (ground, slurry and sand) pumps are pulp pumps of the Finnish company «Metso». When working on highly mineralized water (brines), the «X» type pumps have proven to be the best among centrifugal single-stage pumps.
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Date submitted2018-07-05
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Date accepted2018-08-31
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Date published2018-12-21
The lake Il’men clint, Russia: a potential devonian geopark
- Authors:
- John E.A. Marshall
- David J. Siveter
The Devonian rocks exposed on the shores of Lake Il’men, some 150 km SSE of Saint Petersburg, are important historically in the context of the recognition of the Devonian System. Moreover, they provide unique potential for a range of geological studies today. The non-geological heritage of the area – its flora, fauna, past and current industrial use and cultural links – is also a very worthy one. Since 2001 the area has been recognised asa Specially Protected Natural Territory. A ‘Geopark’ is a unified area of local or wider extent that has been so designated based on its significant geological and associated natural and cultural heritage. There are many positive criteria for considering that the Lake Il’men area could acquire the appellation of a Geopark. Scientific investigations dedicated to understanding the geodynamical conditions operating at Lake Il’men would resolve how to best to help promote the future preservation of this unique natural area.
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Date submitted2015-12-10
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Date accepted2016-02-16
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Date published2016-12-23
Research into the innovative potential of an oil and gas company at different stages of field development
- Authors:
- A. E. Cherepovitsyn
- A. Kraslavski
The paper presents an overview of research into the methods and principles used to assess the innovative potential of an oil and gas company. The validation is provided for the conceptual framework of the innovative potential, which is characterized by a combination of resources having a specific value for the oil and gas sector. The paper gives a detailed overview of the resources, which determine the innovative potential of the oil and gas company. A system of indicators for assessing the innovative potential of the oil and gas company, including six indicator groups, has been proposed. Key distinctive features of the oil and gas company technological development have been determined based on the use of potential for innovation at different stages of the field development. Technical and economic indicators of the oil field development at different stages are described. A concept of Intelligent Field technology is outlined, representing an innovative system, implementation of which determines a level to which the potential for innovation of the oil and gas company is tapped.
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Date submitted2014-09-18
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Date accepted2014-11-15
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Date published2015-06-26
Extraction of iron (III) ions from aqueous solutions with tributyl phosphate
- Authors:
- L. A. Voropanova
- N. B. Kokoeva
High rates of iron (III) ion extraction from aqueous solutions with tributyl phosphate by sequential injection of the extractant and minimal contact time of the solution and the extractant were obtained. The sequential injection of the extractant increases iron extraction and reduces the amount of the extractant used. The best extraction results were obtained from the solutions with concentration 3N HCl, 240 g/dm 3 NaCl and temperature t = 60 С. The flow sheet of the selective iron ions extraction from the aqueous solutions is presented.
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Date submitted2013-07-22
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Date accepted2013-09-24
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Date published2014-03-17
Contemporary Problems of salvaging drill cuttings on the Western Siberia oilfields of the final stage of development
- Authors:
- V. V. Katsilo
The article deals with the problem of disposing of industrial and technological drilling wastes due to the application of salt biopolymer drilling fluids for extraction of residual oilfields of Western Siberia, which are at an final stage of development using the technology of directional drilling. The problem of disposal of drilling waste in the oilfields of the final stage of development is proposed to solve through the introduction of protective functions of the complex engineering activities, including, the development of waterproofing layer of clay cuttings, which is formed by drilling the top of the production casing, for different host rock cuttings.
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Date submitted2009-10-29
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Date accepted2009-12-26
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Date published2010-09-22
Control system of rock pressure at the «Antey» deposit
- Authors:
- B. A. Prosekin
- E. A. Ilin
The paper deals with the geomechanical monitoring system of the Antey deposits of uranium ores. Characteristics of the methods and means for rock pressure control are given.
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Date submitted2009-08-02
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Date accepted2009-10-10
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Date published2010-02-01
The analyses of influence of goafs on the state of developmental excavations as applies to Starobinsky potassium salt deposit
- Authors:
- A. P. Gospodarikov
- L. A. Bespalov
The analysis of stress-strain state near excavations and influence of goafs on its redistribution were carried out in this work as applies to coal and salt deposits. The indirect boundary element method was chosen as a tool of research.
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Date submitted2009-07-29
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Date accepted2009-09-29
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Date published2010-04-22
State examination of mineral reserves in the system of wise utilization of the earth’s interior
- Authors:
- Yu. A. Podturkin
The major problem of bodies of the government in sphere of regulation of attitudes protection of reserves creation of conditions for rational use of resources. The basic role in its decision is played with examination protection of reserves. Maintenance of effective carrying out of examination demands its constant perfection with reference to market conditions with use of the international criteria regarding both calculation and an estimation of stocks, and drawing up design and the engineering specifications on development of mineral deposits.
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Date submitted2008-10-21
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Date accepted2008-12-25
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Date published2009-12-11
Comparative analysis of spiriferida complexes of the frasnian stage in the south of Novaya Zemlya and one-aged complexes of East-European platform and other districts
- Authors:
- D. V. Bezgodova
The Article contains a brief characteristic of spiriferida (brachiopod) complexes spread in the Frasnian sediments in the South of Novaya Zemlya, and their comparison with one-aged complexes of several regions of East-European platform, such as Main Devonian field, Central districts, the Volga-Urals region, South Timan, south-western districts and also outlying districts of the Kuznetsk coal basin and North-West of Russia.