Time filter

Source Type

Tretyak A.V.,Donskoy Ore Dressing and Processing Enterprise | Tretyak A.V.,Pacific Research Fisheries Center
Gornyi Zhurnal | Year: 2013

This article describes the basic complex of typical geomechanic problems, which make a negative influence on the stability of mine openings, which are carried out in instable massif on deep horizons. Development and introduction of timely technological decision, related to the provision of stability of underground mine openings, requires the accounting of the whole complex of regularities of formation of stress-strain state of rock massif. There is developed the complex of basic measures and technical decisions for the guaranteeing of stability of underground mine openings on their carrying out stage. There is given a brief description of existing methods of calculation of frame metal support, taking into account the results of carried out mathematical modeling of formation of stress state of underground construction. This modeling is based on the basic states of underground construction mechanics about the interconnection of massif support, as the unite deformable system elements. The calculation methodology of standing support was developed for the purpose of full value realization of complex of measures and technical decisions, related to the provision of stability of underground mine openings on their carrying out stage. According to the foregoing stage, there were carried out the optimal support calculations for the deep horizons of mines of Donskoy Ore-Dressing and Processing Enterprise. There are given the results of the calculations of comparative correspondence of carrying capacity of applied support (in various regimes) and defined values of components of initial stresses field in near-boundary massif.


Til V.V.,Transnational Company KazKhrom JSC | Bekeev M.M.,Donskoy Ore Dressing and Processing Enterprise | Bolikov V.E.,Russian Academy of Sciences
Gornyi Zhurnal | Year: 2013

Geological peculiarities of industrial area of the «10-th anniversary of Kazakhstan independence» mine are considered as complex. These peculiarities are characterized by the following factors: -strong fragmentation of rock massif; -powerful tectonic zones, falling towards the mined out space of shafts; -low stability of rocks in exposed mine openings. Mining and geological conditions of the central group of shafts of the «10-th anniversary of Kazakhstan independence» mine belong to the extremely difficult conditions, which do not have analogues in the country's practice. Anisotropy of a stress field on the shaft perimeter was revealed on the support on the basis of inspection of the stress-strain state of shafts support of the «10-th anniversary of Kazakhstan independence» mine. At the same time, the maximum stresses in the support appear transversely to the line of maximum stresses in rock massif. Level of maximum stresses in separate tubings in the most powerful support reached -386 MPa. In the conditions of Don chromite deposits, there is offered the combined scheme of sinking operations in the serpentinite massif. The most difficult site of shafts construction in serpentinite massif is the sinking of a shaft junction with the horizon, where takes place the most often support deformation. For these conditions, there is developed the special technological scheme of sinking of junction with advancing temporary support, consisting of anchors with reinforcing grid and monolithic concrete (250 mm thickness). Fastening of a shaft junction by permanent support is carried out after the junction sites sinking. For the purpose of sinking operations in serpentinite rock massif, there was developed the construction technology with application of advancing strengthening anchor support and pliable keramzite concrete fixing space. The developed and offered technologies of carrying out and fastening of deep shafts are tested on separate sites of constructed «10-th anniversary of Kazakhstan independence» mines. This makes it possible to recommend these technologies for industrial usage, for the purpose of accident-free opening and development of deep horizons of chromite deposits in rather difficult mining and geological conditions.


Til V.V.,Transnational Company KazKhrom JSC | Bekeev M.M.,Donskoy Ore Dressing and Processing Enterprise | Sashurin A.D.,Russian Academy of Sciences
Gornyi Zhurnal | Year: 2013

In many respects, the future of global ferrochromium market depends on the state of extraction of chromium ores in the Republic of South Africa and Kazakhstan. These two countries have near 85% of global reserves. The whole amount of chromium ore of Kazakhstan is situated in Aktobe region, in South-Kempirsay group of deposits, which have been developed since 1938 by Donskoy Ore-Dressing and Processing Enterprise - subsidiary of Transnational Company «KazKhrom». For the period of 40 years, the enterprise has been used only the open-cast method of extraction of ore from not deep deposits. However, the basic reserves of ores were situated on deep horizons. As a result, the «Molodezhnaya» mine with 450-550 m of underground mining depth was set in exploitation in 1981. The «10-th anniversary of Kazakhstan independence» mine was set in exploitation in 2001. The second stage of this mine foresees the deepening of underground mining to 1000-1200 m. Deepening of mining at the deposits, developed by Donskoy Ore Dressing and Processing Enterprise, is followed by the problems of guaranteeing of stability of permanent and preparatory mine openings and controlling of rock pressure in the extraction area. These problems are caused by the complex structure of rock massif with developed tectonics and high level of tectonic stress anisotropy. On the basis of the carried out researches and approaches, developed, according to their research results, there were defined the basic directions of solving of the foregoing problems, which will make it possible to provide the following operations: -successful mastering of reserves on the depths to 1000-1200 m; -long-term development of Donskoy Ore Dressing and Processing Enterprise; -keeping the leading positions of the enterprise and Kazakhstan on the global ferrochromium market.


Podoprigora O.A.,Donskoy Ore Dressing and Processing Enterprise | Bondarenko G.V.,Donskoy Ore Dressing and Processing Enterprise | Neverov A.M.,Donskoy Ore Dressing and Processing Enterprise | Ozornin I.L.,Russian Academy of Sciences
Gornyi Zhurnal | Year: 2013

During the sinking of "Ventilyatsionnyy" shaft to the 970 m depth, there was carried out the complex of geomechanical and geophysical natural researches of stress-strain state of tubing support and surrounding rock massif. This complex of researches has shown that the currently applied sinking technological schemes and parameters of shaft support and inset openings does not completely meet the requirements of low strength and high-intensive massifs of serpentite rocks, which are characteristic for the deep horizons of «10-th anniversary of Kazakhstan independence» mine. In the area of shaft junction with -560 m horizon, the stresses of more than a half of researched tubings became closed to the design strength. At the same time, the stresses of two tubings exceeded the tensile strength of cast iron, which led to the disturbance of edges and back edges of tubings. In connection with this, on the basis of results of experimental and analytic researches, for the purpose of construction of junction of -600 m horizon of "Ventilyatsionnyy" shaft at the «10-th anniversary of Kazakhstan independence» mine, there is recommended the top down layer sinking with application of temporary reinforced-concrete support with the following installation of tubing shaft support, along with layer construction of reinforced-concrete support of junction opening. The temporary reinforced-concrete support is a combination of metallic grain, pressed to the check by anchors, and a concrete layer of the «B 25» grade (200-250 mm thickness). As a result, intense on the constant support of shaft and inset will be significantly lesser than in the earlier applied scheme, because the tubing support of shaft and reinforce-concrete support of junction opening will be installed after the realization of the most part of displacements of checks and adjoining massif. The researches were carried out with the support of the Ministry of Education and Science of Russian Federation (agreement No. 8348) and integration project of Presidium of Ural Branch of Russian Academy of Sciences No. 12-I-5-2050 (12-I{cyrillic}-5-2050).


Loginov N.M.,Donskoy Ore Dressing and Processing Enterprise | Imekeshova M.A.,Donskoy Ore Dressing and Processing Enterprise
Gornyi Zhurnal | Year: 2013

The basic stages of technological chain of the factory of concentration and pelletization of chromium ores are the small grades concentration department (2005) and small and thin grades concentration department (2009). Technological cycle of chromium ores processing with the coarseness of -10 mm is finished at the pellet production areas. Improvement of technological scheme was carried out in 2008, along with introduction of the following new equipment: -screen for the classification of initial ore; -centrifugal concentrator «Falkon» for the concentration of -0.071 mm of the grain size fraction; -disc filter DOO-16 (D{cyrillic}OO-16) for the dehydration of the concentrate with coarseness of -0.5 mm. The foregoing improvement and introduction were carried out for the purpose of increasing of output of concentrate with -5 mm coarseness and increasing of extraction of metal into the concentrates of the small grades concentration department. As a result, extraction of metal increased to 83.9% and pellets production reached 423.8 th. t per year. For the purpose of stable supplement of the pellet production areas with initial raw materials and manufacturing of the concentrate of -5 mm grade, there is foreseen the construction of additional (parallel) technological line of the small grades concentration department. As a result of realization of this project (2013), there is planned to increase the productivity of the small grades concentration department on the initial ore of -10 mm of the grain size fraction to 1 mln. t. per year. Launching of additional line of the small grades concentration department will make it possible to do the following operations: -provision of the pellet production areas with high quality initial raw materials; -decreasing or complete exclusion of the consumption of rich ore of -10 mm of the grain size fraction; -decreasing of losses of raw materials during the pellets manufacturing.


Til V.V.,Transnational Company KazKhrom JSC | Bekeev M.M.,Donskoy Ore Dressing and Processing Enterprise
Gornyi Zhurnal | Year: 2013

Kazakhstan has the largest amount of reserves and extraction capacities of chromium ores in the world, after the Republic of South Africa. Reserves of Kazakhstan chromites are situated in the Kempirsay massif, on the territory of Aktobe region. These reserves are developed by Donskoy Ore-Dressing and Processing Enterprise (Transnational Company «KazKhrom»). With near 20 mln. t. of total global production of chromium ore per year, Donskoy Ore-Dressing and Processing Enterprise extracts near 4 mln. t. of ore. Kazakhstan chromite ores have the highest content of chromium oxide (50%) and low concentrations of detirmental impurities (phosphorous and sulphur). Such content provides the possibility of usage of this mineral raw materials in ferroalloy, refractory and chemical branches of industry. This article shows the basic stages of the 75-th year history of development of Donskoy Ore-Dressing and Processing Enterprise - from opening and mastering of unique chromite deposits in Kazakhstan till nowadays. There are presented the realized projects of extraction and concentration of mineral raw materials and projects of development of industrial and social infrastructure. This article also describes the problems of mastering of deposits' deep reserves and prospects of further long-term development of enterprise. Nowadays, Donskoy Ore-Dressing and Processing Enterprise is a high-technological and efficiently organized mining enterprise with high-qualified personnel, provided by stable work and modern social infrastructure. All the foregoing creates the basis for further long-term development of enterprise and successful solving of complex problems of mastering of deep reserves of unique deposit of chromites and, consequently, social-economic welfare of workers and citizens of a town.

Loading Donskoy Ore Dressing and Processing Enterprise collaborators
Loading Donskoy Ore Dressing and Processing Enterprise collaborators