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Date submitted2024-04-11
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Date accepted2024-06-03
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Date published2024-07-04
Assessment of the efficiency of acid mine drainage purification (using the example of copper-pyrite mines in the Middle Urals)
According to the results of the anti-rating of regions with extreme pollution of watercourses in the Sverdlovsk region, the largest number of polluted rivers has been recorded in recent years – more than a quarter of all high and extremely high pollution. One of the sources of pollution of natural water bodies in the Middle Urals are closed and flooded copper-pyrite mines, where acidic mine drainage continue to form and unload to the surface. Several of them have organized collection and a two-stage acidic drainage purification system, including neutralization with lime milk and settling in a clarifier pond. Despite the identical schemes, different indicators of pollutants are recorded during discharge into water bodies. The aim of the work is to evaluate the effectiveness of the applied acid mine drainage purification system and identify the parameters affecting the quality of treated mine water. Laboratory studies were performed using methods of flame emission spectrometry, flame atomic absorption, atomic absorption spectrometry, mass spectrometry with ionization in inductively coupled plasma, potentiometric, etc. It has been established that the existing mine drainage purification system at the Degtyarskii mine makes it possible to significantly reduce the concentrations of most toxic components of mine waters to almost standard values. At the Levikhinskii mine, the multiplicity of exceeding the maximum permissible concentrations reaches hundreds and thousands of times. To achieve a higher degree of purification, it is necessary that the duration of passive purification is sufficient for the reactant to interact with acidic waters. However, to ensure this possibility, it will require the creation of a cascade of ponds with an area of several thousand hectares. If the current two-stage system is quite effective for the Degtyarskii mine, then for Levikhinskii it is necessary to switch to the use of more modern systems, including three stages of purification.
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Date submitted2023-07-25
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Date accepted2024-05-02
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Date published2024-08-26
Finite element analysis of slope failure in Ouenza open-pit iron mine, NE Algeria: causes and lessons for stability control
Slope failures in mining engineering pose significant risks to slope stability control, necessitating a thorough investigation into their root causes. This paper focuses on a back analysis of a slope failure in the Zerga section of the Ouenza – Algeria open-pit iron mine. The primary objectives are to identify the causes of slope failure, propose preventive measures, and suggest techniques to enhance stability, thereby providing crucial insights for monitoring slope stability during mining operations. The study commenced with a reconstruction of the slopes in the affected zones, followed by a numerical analysis utilizing the Shear strength reduction method within the Finite element method (SSR-FE). This approach enables the examination of slope stability under both static and dynamic loads. The dynamic load assessment incorporated an evaluation of the vibrations induced by the blasting process during excavation, introducing seismic loading into the finite element analysis. The findings reveal that the primary triggering factor for the landslide was the vibration generated by the blasting process. Furthermore, the slope stability was found to be critically compromised under static loads, highlighting a failure to adhere to exploitation operation norms. The challenging geology, particularly the presence of marl layers where maximum shear strain occurs, contributed to the formation of the landslide surface. The study not only identifies the causes of slope failure but also provides valuable lessons for effective slope stability management in mining operations.
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Date submitted2022-01-21
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Date accepted2022-11-14
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Date published2023-08-28
Strategy of mine ventilation control in optimal mode using fuzzy logic controllers
- Authors:
- Aleksei V. Kashnikov
- Yuri V. Kruglov
The issues related to improving the efficiency of automatic ventilation control systems of mines that regulate the air supply to the mine in accordance with the need are considered. During the tests of such a system in the 3RU mine of OAO Belaruskali, the shortcomings of its existing, implementation, associated with the incorrect choice of the most difficult-to-ventilate direction, were revealed. The possibilities of implementing a control strategy, in which the system automatically determines the optimal configuration of the operating modes of fans and regulators, are demonstrated. As an alternative to the implemented algorithms, it is proposed to use a fuzzy control device to account for the nonlinearity of the dependence of the input and output parameters of ventilation equipment and to set the conditions for the optimal operating mode of the system in a declarative form. To assess the effectiveness of the proposed approach, the data of simulation modeling of the current ventilation mode and the transition from one ventilation mode to another are analyzed with comparison with the actual data of the system operation. The simulation results show that the use of an upgraded control scheme for the main ventilation fan based on fuzzy logic in the implementation of automatic ventilation control systems makes it possible to eliminate the possibility of a shortage of fresh air in the regulated directions of its movement, as well as excessive power consumption of the main ventilation fan.
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Date submitted2020-06-10
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Date accepted2020-11-19
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Date published2021-04-26
Influence of jarosite precipitation on iron balance in heap bioleaching at Monywa copper mine
Ferric iron is an important oxidant in sulfide ore bioleaching. However, recirculating leach liquors leads to excess iron accumulation, which interferes with leaching kinetics and downstream metal recovery. We developed a method for controlling iron precipitation as jarosite to reduce excess iron in heap bioleaching at Monywa copper mine. Jarosite precipitation was first simulated and then confirmed using batch column tests. From the simulations, the minimum pH values for precipitation of potassium jarosite, hydronium jarosite, and natrojarosite at 25 °C are 1.4, 1.6, and 2.7, respectively; the minimum concentrations of potassium, sulfate, ferric, and sodium ions are 1 mM, 0.54, 1.1, and 3.2 M, respectively, at 25 °C and pH 1.23. Column tests indicate that potassium jarosite precipitation is preferential over natrojarosite. Moreover, decreased acidity (from 12 to 8 g/L), increased temperature (from 30 to 60 °C), and increased potassium ion concentration (from 0 to 5 g/L) increase jarosite precipitation efficiency by 10, 5, and 6 times, respectively. Jarosite precipitation is optimized by increasing the irrigating solution pH to 1.6. This approach is expected to reduce the operating cost of heap bioleaching by minimizing the chemicals needed for neutralization, avoiding the need for tailing pond construction, and increasing copper recovery.
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Date submitted2020-05-08
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Date accepted2020-06-12
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Date published2020-12-29
Gas-dynamic roof fall during the potash deposits development
In the development of practically all potash salt deposits, the study of gas-dynamic phenomena (GDP) is one of the most difficult tasks to ensure mining safety. Sudden salt and gas outbursts, dynamic breakdown, which are accompanied by intense gas release and possible broken rock carry-over into the mine workings, are associated with GDP. Geological preconditions for the GDP development are often the layered structure of the salt rock mass, the presence of interlayers and layers of salt clays. For the conditions of the Usolsky potash plant mine, complex studies of factors that characterize the possibility of gas-dynamic roof fall of the stoping rooms were carried out. In mine studies, free gases pressure and the initial velocity of gas release in the rocks of the roof workings were determined. The obtained experimental estimations were used as a parametric basis for mathematical modeling of geomechanical processes under conditions of a near-contact accumulation of free gas. The deformation of a layered salt mass produced by a room development system was described by the model of an ideal elastic-plastic medium with internal friction. The parabolic envelope of Mohr circles was used as a plasticity criterion in the compression area. In the numerical implementation, the deformation of clay contacts was modeled by Goodman contact elements. Based on the results of multivariate numerical calculations, it is established that the main factors determining the possibility of implementing GDP are the additional gas pressure at the contact, the width of the workingspan, and the distance from the roof to the first gas-containing contact. With multi-level lamination of roof rocks, there is a danger of large sources of GDP formation and the mechanism of successive fall of layers in an instant mode is implemented.
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Date submitted2018-01-12
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Date accepted2018-03-08
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Date published2018-06-22
A method for controlling siltation of water catchments of district drainage systems of kimberlite mines
- Authors:
- N. P. Ovchinnikov
High contamination of mine water leads to intensive siltation of water catchments of district water drainage installations of kimberlite mines in Russia, because of which their pumping equipment periodically works in non-stationary regimes. At present, a number of known methods are used to limit the operation of pumping equipment in non-stationary modes: equipping the pump with a hand hoist to regulate the depth of lowering its suction pipeline into the sinkhole; preliminary dismantling of one of the two screen filters, mounted in the suction pipeline of the pump, which has smaller cells. Experience in the operation of water-drainage farms of kimberlite mines shows that these two methods allow to prevent the operation of pumping equipment in non-stationary modes only for a short period of time. A mine drainage installation is proposed, the technical result of which is the effective struggle against the silting of the water catchments of the district drainage systems of the kimberlite mines of the country.
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Date submitted2014-11-07
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Date accepted2015-01-07
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Date published2015-10-26
The concept of reducing the risks of potash mines flooding caused by groundwater inrush into excavations
- Authors:
- V. P. Zubov
- A. D. Smychnik
Results of the analysis of factors influencing the probability of accidental groundwater inrush into mine workings of salt (potash, potassium and magnesium) mines are given in the article. The cases of the potash mine flooding that occurred in different countries with developed mining industry are given. It is shown that at the present technical and scientific level of solving this problem the unexpected groundwater inrush in potash mines usually results in the shutdown of the enterprise and negative ecological consequences. It is pointed out that the underground waters flow into the mines through water-conducting fractures of either natural or technogenic origin which location and influence on a mine was almost impossible to predict at the design stage under existing regulations. The concept of reducing the risks of potash mine flooding caused by underground waters in-rush is formulated. Administrative and technical measures which allow reducing the risks of potash mine flooding caused by groundwater inrush into the excavations are considered.
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Date submitted2009-10-07
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Date accepted2009-12-22
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Date published2010-09-22
Providing of safe conditions for mining of shaftbottom protective pillars in deep ore mines at Тalnakh
- Authors:
- V. A. Zvezdkin
- A. G. Anokhin
- R. B. Galaov
Consideration is given to the causes complicating the mining of shaftbottom pillar and protection of shaft lining. The analysis is given to the formation of stress-strain state of the protective pillar and its enclosing rocks. Practical recommendations are given for control of deformation and stresses in the shaftbottom mass during extraction of protective pillars in deep ore mines at Talnakh.
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Date submitted2009-10-29
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Date accepted2009-12-09
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Date published2010-09-22
Problems and ways of exploration of the raw material resources base of the Zapoliarny branch of the Norilsk Nickel CO
Consideration is given to the geological, mining and operating conditions of the Norilsk industrial district. The analysis is made of the present-day state of mining production of the Zapoliarny branch of the Norilsk Nickel Co. The principal trends in the safe and efficient exploration of the raw material resources base have been stated within the Norilsk industrial district .
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Date submitted2009-07-24
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Date accepted2009-09-20
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Date published2010-04-22
Investigation of stress-strain state of floor of the dividing mass of deep-lying ore mines at Тalnakh
The paper contains the results and analysis of the formation of stress-strain state in blocky structure enclosing the dividing mass. The regularities were established on the influence of blocky structure undermining on stress state of the floor of dividing mass. Recommendations are given for the safe mining in the dividing rock mass.
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Date submitted1951-07-24
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Date accepted1951-09-10
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Date published1952-12-23
Application of cyclograms for mine transport calculations
- Authors:
- N. V. Filatov
When selecting units and determining the optimal parameters of the designed machines, as well as during mass calculations during research, it is most convenient to use graphical calculation methods. Graphic works are characterized by the speed of operations, significant simplicity, high accuracy and, which is especially important when choosing options - clarity. There are many different methods of graphical calculations. One of the most common is the nomographic method, based on the graphical representation of functional dependencies. The method of vector calculations is also widely used. Cyclographic methods are used for circular functional dependencies and represent a type of vector calculations. Cyclograms are distinguished by their clarity and simplicity of construction. They can be characteristics of machines and their operating processes. The use of cyclograms is known in electrical engineering, mechanics, elasticity theory, etc. Cyclograms have not been used in transport. The proposed work shows the general principles of cyclographic calculations that can be used both for studying transport and for calculating machine elements. When selecting units and determining the optimal parameters of the designed machines, as well as during mass calculations during research, it is most convenient to use graphical calculation methods. Graphic works are characterized by the speed of operations, significant simplicity, high accuracy and, which is especially important when choosing options - clarity. There are many different methods of graphical calculations. One of the most common is the nomographic method, based on the graphical representation of functional dependencies. The method of vector calculations is also widely used. Cyclographic methods are used for circular functional dependencies and represent a type of vector calculations. Cyclograms are distinguished by their clarity and simplicity of construction. They can be characteristics of machines and their operating processes. The use of cyclograms is known in electrical engineering, mechanics, elasticity theory, etc. Cyclograms have not been used in transport. The proposed work shows the general principles of cyclographic calculations that can be used both for studying transport and for calculating machine elements.
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Date submitted1951-07-29
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Date accepted1951-09-20
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Date published1952-12-23
Experimental verification of formulas for calculating natural mine draft
- Authors:
- Sh. Kh. Kilkeev
"In connection with the increase in the depth of development, reaching, in particular, 1000-1200 m in a number of Donbass mines, interest in the issue of natural draft is growing, especially in mines with high temperatures. Natural draft is also important from the point of view of energy conservation. For ventilation of deep mines, fans with a capacity of up to 300-400 m3/sec with an annual power consumption of about 20-30 million kWh will be installed. With such enormous energy resources required for ventilation, taking into account the depression of natural draft when choosing fans will save significant funds for the national economy. Natural draft is of particular importance when ventilating mines of metal mines located in mountainous areas. Many of them, even large ones, are ventilated exclusively by natural draft. Thus, according to measurements in January 1947, at one of the mines of the Soviet Union, with a depression of natural draft of 12.5 mm H2O in winter, 2000 m3/min of air was supplied, which fully ensured the normal operation of the mine. From the above it follows that the question of natural draft in mines is of great practical interest and its correct calculation has considerable production significance.