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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 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 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 submitted2013-07-18
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Date accepted2013-09-02
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Date published2014-03-17
Rock mechanics problems decision algorithm for bottom layers of potash salt deposits
Decision algorithm for rock mechanics problems for bottom layers of potash deposits is suggested. Flow chart for the algorithm and it’s parts is shown. The algorithm represents the method to choose excavation technology for multi-layer potash deposits.
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Date submitted2013-07-28
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Date accepted2013-09-27
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Date published2014-03-17
The analysis of the stress-and-strain state in vicinity of mining excavations
- Authors:
- A. A. Sankovskii
- E. R. Kovalsky
Estimation of the strain-and-stress state and displacement of the waterprotective layers in vicinity of mining excavations in conditions of SKRU-3 mine (Uralkali Group) is done. It is shown that loadings on pillars on layer Kr.II exceed 15-20 % loadings on layer AB.
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Date submitted2009-08-26
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Date accepted2009-10-25
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Date published2010-02-01
The improvement of selective extraction of thick potash seams mined with room and pillar mining method
- Authors:
- Yu. G. Sirenko
- M. Yu. Brychkov
- E. R. Kovalsky
Technological scheme of selective extraction of a complex thick potash seam on the basis of cutting machine «Bucyrus Model 25 M0» is proposed. Stable pillars’ width and room dimensions are calculated. Economical effect is also presented.