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Date submitted2022-10-17
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Date accepted2023-02-13
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Date published2023-04-25
Environmental geotechnology for low-grade ore mining with the creation of conditions for the concurrent disposal of mining waste
Due to the constantly deteriorating environmental situation in the regions with mining enterprises, the article considers the topical issue of disposing the maximum possible volume of waste from the mining and processing of low-grade ferrous ores through the creation of an effective underground environmental geotechnology. Traditional procedure with descending mining of reserves with a caving system does not allow waste to be disposed of in a gob. The idea is to use geotechnology based on the ascending order of mining the ore body, room excavation, leaving truncated pillars, and staggered arrangement of adjacent rooms in height, which makes it possible to form containers for waste disposal in the form of a cementless backfill. The main characteristics of the proposed procedure are investigated and compared with the traditional procedure of low-grade iron ores mining. It was established that from the point of view of the complete extraction of reserves and the unit costs for the preparatory-development operations, the processes are comparable, while in terms of the mining quality, the proposed option is much more efficient. Evaluation of environmental geotechnology by the criterion of waste disposal, performed according to the proposed methodology, showed that the combination of these technical solutions ensures the placement in the formed gob from 80 to 140% of all waste generated during the mining and beneficiation of low-grade iron ores.
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Date submitted2021-02-24
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Date accepted2021-10-18
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Date published2021-12-16
A probabilistic approach to the dynamic cut-off grade assessment
Cut-off grade is an important conditioning parameter that determines the quantity and quality of recoverable reserves and development efficiency. Today, Russian mining companies operate with certified quality requirements. By setting permanent quality requirements, the government seeks to prevent depletion of reserves, reduced production during periods of falling prices, and decreased budget revenues, expressing the interests of all members of society. But to what extent do the permanent quality requirements protect the interests of the state? The answer to this question is ambiguous and does not lie on the surface. The State Commission for Reserves and domestic researchers are working to find a rational solution to the problem of quality requirements. One solution is dynamic quality requirements. The effectiveness of their application has been proven for individual mining companies, but it is incorrect to transfer these conclusions to the entire mineral resource base of the country. This article presents a new approach to determining the dynamic cut-off grade, which varies depending on the price of minerals. The dynamic cut-off grade is proposed to be determined based on the indicators of constant requirements to the quality of exploration work, using the maximum allowable costs in the region. The approach allows to calculate the effect of the introduction of dynamic cut-off grade in the practice of subsurface use for the state (in the form of the amount of taxes received) and for subsoil users (in the form of the amount of income). For a group of gold-bearing deposits with open-pit mining method, it was established that the development of reserves using dynamic values of the cut-off grade in periods of price changes ensures compliance with the interests of the state and subsoil users.
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Date submitted2016-10-30
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Date accepted2017-01-14
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Date published2017-04-14
HYDRO-IMP technology for upgrading of heavy petroleum
- Authors:
- Khorkhe Anchita
Hydroprocessing is one of the most important processes in petroleum refining industry, not only for upgrading of heavy oils but also for producing low-impurity content fuels and preparing feeds for various conversion processes. Experimental results obtained in pilot plant and semi-commercial scales for hydroprocessing of heavy oils are reported in this work. Mexican heavy crude oils (10, 13 and 16°API) with high amount of impurities were used for all tests. Hydroprocessing was conducted at moderate reaction severity in two fixed-bed reactors in series. Removals of sulfur, metals and asphaltenes, as well as changes of API gravity and viscosity were monitored at different reaction conditions with time-on-stream. Upgraded oils with reduced amounts of impurities and increased API were obtained, keeping sediment formation below maximum allowable content. Removal of impurities was higher in semi-commercial scale compared with pilot plant test. Have been proved that the heavier the feed the greater the gain in product quality. For instance, 10°API crude can increase its gravity up to ~22°API (Δ°API = 12), while 16°API crude increases its gravity up to ~25°API (Δ°API = 9). Sediment formation was also kept below 0.05 wt % and no other problems (excessive reactor delta-P, plugging, etc.) were observed during the test.
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Date submitted2015-10-03
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Date accepted2015-12-10
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Date published2016-08-22
Directions and prospects of using low grade process fuel to produce alumina
- Authors:
- O. A. Dubovikov
- V. N. Brichkin
Power consumption across the globe is constantly increasing for a variety of reasons: growing population, industrialization and fast economic growth. The most widespread gaseous fuel – natural gas – has the low production cost. It is 2-3 times cheaper than liquid fuel production and 6-12 times cheaper than coal production. When natural gas is transported to distances from 1.5 to 2.5 thousand km by the pipeline, its cost with account of transportation is 1.5-2 times less than the cost of coal and the fuel storage facilities are not needed. Plants powered by natural gas have the higher efficiency as compared to the plants operating on other types of fuel. They are easier and cheaper to maintain and are relatively simple in automation, thus enhancing safety and improving the production process flow, do not require complicated fuel feeding or ash handling systems. Gas is combusted with a minimum amount of polluting emissions, which adds to better sanitary conditions and environment protection. But due to depletion of major energy resources many experts see the future of the global energy industry in opportunities associated with the use of solid energy carriers. From the environmental perspective solid fuel gasification is a preferred technology. The use of synthetic gas was first offered and then put to mass scale by English mechanical engineer William Murdoch. He discovered a possibility to use gas for illumination by destructive distillation of bituminous coal. After invention of the gas burner by Robert Bunsen, the illumination gas began to be used as a household fuel. The invention of an industrial gas generator by Siemens brothers made it possible to produce a cheaper generator gas which became a fuel for industrial furnaces. As the calorific value of generator gas produced through gasification is relatively low compared to natural gas, the Mining University studied possibilities to use different types of low grade process fuel at the Russian alumina refineries as an alternative to natural gas, access to which is restricted for some of the regions.
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Date submitted2015-10-07
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Date accepted2015-12-01
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Date published2016-08-22
Evaluating possible industrial applications of combustible shales and shale ash wastes
- Authors:
- N. K. Kondrasheva
- S. N. Saltykova
Today energy consumption is constantly growing while explored reserves of easily accessible oil are depleting, which is a reason why most countries tend to diversify their energy mix, develop non-hydrocarbon energy sources and use domestic types of fuel, including the low grade ones. Thereby interest is raised to such a source of hydrocarbons as combustible shales. Combustible shales appear to be one of the highest-potential types of organic raw materials, which may offset and in future even substitute oil products and gas. The paper is investigating behavior and structure of combustible shales during heat treatment in order to identify their possible industrial applications. A synchronous thermal analysis has been held, chemical composition of combustible shales’ mineral fraction and optimal conditions for shale fines briquetting have been determined.
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Date submitted2014-07-20
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Date accepted2014-09-18
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Date published2014-12-22
Use оf renewable energy sources in the coal industry
- Authors:
- A. V. Limanskii
- M. A. Vasileva
There are three fundamental basic documents in energy conservation and energy efficiency today: the Energy Strategy in the period up to 2030; the Federal Law «On energy-saving and energy efficiency and in amending particular legislative acts of the Russian Federation»; and the State Energy Conservation and Energy Efficiency Program in the period up to 2020. In recent years, the upward trend in the use of renewable energy sources (RES) is becoming all the more evident. Until recently, the development of energy has seen a clear pattern: the areas of energy which have developed most are those which have a quite fast direct economic effect. The social and environmental impacts associated with these areas were considered only as incidental, and their role in decision-making was negligible. With this approach, we considered RES only as a future energy source, when traditional energy sources have been exhausted, or when obtaining them becomes extremely expensive and timeconsuming. The primary driver behind the intensive development of RES has been public pressure based on environmental concerns, rather than economic calculations about the future. The economic potential of the world’s renewable energy is currently estimated at 20 billion tons of oil equivalent per year, which is twice the annual output of all fossil fuels. This fact shows us the path of energy development in the near future. In this paper, on the basis of the laws of the Russian Federation, renewable energy in the coal industry is considered. We describe the experience and prospects of the use of mine water and burning rock dumps.
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Date submitted2009-08-23
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Date accepted2009-10-17
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Date published2010-02-01
Reseach of cutoff grade influence on economic performances of mining
- Authors:
- M. D. Morozov
Research of cutoff grade influence on economic performances of mine as well as parameters and configuration of ore deposits with the help of the advanced geoinformation system were carried out. Computer modeling of an ore chute was made; the results of calculation were presented, involvement is given.
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Date submitted2009-07-22
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Date accepted2009-09-18
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Date published2010-04-22
Higher grade filling due to horizontal layers extraction in Yakovlevsky ore deposit
A complex of technology and organization methods to higher grade filling due to horizontal layers system of extraction rich ferrous metal ores for various stages of mining is presented.