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Date submitted2024-04-24
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Date accepted2024-09-24
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Date published2024-11-12
Study and justification of the combination of beneficiation processes for obtaining flake graphite from technogenic carbon-containing dusts
The most important task of modern production development is to provide the mineral and raw materials sector of the economy with resources included in the list of strategic raw materials, including flake graphite. In addition to natural raw materials, the source of its obtaining can be metallurgical production wastes not involved in processing. Development of metallurgical dust beneficiation technology will solve the problem of obtaining high-purity flake graphite with a crystal structure close to ideal and in demand in the production of high-tech materials. It will allow creating a renewable raw material base of graphite and utilising metallurgical production wastes. The research included the study of dust beneficiation by coarseness, magnetic and flotation methods, the influence of dust disintegration processes on beneficiation indicators. Based on the established technological properties of the components of dusts, magnetic, flotation and gravity beneficiation methods can be applied for their separation in different sequence. It is shown that dusts from different sites have different enrichability by these methods, and it should be taken into account when developing a complex technology of their processing. The degree of beneficiation increases in a row of dusts from the blast furnace shop (BF) – electric steel smelting shop (ESS) – oxygen-converter shop (OCS). The method of grinding has a significant influence on the separation indicators – at dry grinding in a centrifugal-impact mill with subsequent pneumatic classification the quality of graphite concentrates increases by 22.7 % of carbon for BF dust and by 13.48 % of carbon for ESS dust. OCS dust beneficiation indicators are high at coarse grinding with steel medium – mass fraction of carbon 96.1 %.
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Date submitted2023-04-13
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Date accepted2023-10-25
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Date published2025-02-25
Assessment of the ecological state of aquatic ecosystems by studying lake bottom sediments
- Authors:
- Mariya A. Chukaeva
- Tatyana V. Sapelko
The article presents the results of coupled palynological and geochemical studies of five various genesis lakes, located along the route of the expedition “In the footsteps of Alexander von Humboldt in Siberia, Altai and Eastern Kazakhstan”, dedicated to the double anniversary: the 190th anniversary of the expedition across Russia of the famous scientist and his 250th birthday. A geochemical analysis of water and bottom sediments of Ik Lake (Siberia), Lakes Kolyvanskoe and Beloe (Altai), Lake Bezymyannoe (Kazakhstan) and Nagornyi Pond (Altai) was carried out. Based on their results an assessment of studied lakes ecological state was given through single and integral criteria. A high level of pollution was noted for Nagornyi Pond and Lake Bezymyannoe, which is caused by a significant technogenic load from nearby mines. This is consistent with the data of palynological research. The aquatic ecosystems of Lakes Kolyvanskoe and Beloe are characterized by a satisfactory ecological situation, but they experience an increased recreational load. The results of spore-pollen analysis and analysis of non-pollen palynomorphs showed the low ability of these lakes to self-healing. The most favorable ecological state and high self-cleaning capacity were noted for Lake Ik, which is consistent with the data of palynological studies. It is being confirmed with the results of palynological studies. It was therefore concluded about the ability to make a quick assessment of the aquatic ecosystems’ ecological state by studying lakes using coupled palynological and geochemical analysis.
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Date submitted2022-06-27
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Date accepted2023-06-20
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Date published2023-12-25
Analysis of the problems of high-quality drinking water extraction from underground water intakes on Vysotsky Island in the Vyborg district of the Leningrad region
This article presents the results of drilling, experimental filtration work and laboratory studies aimed at assessing the resources and quality of groundwater in the licensed area of Vysotsky Island located in the Leningrad region, in the Gulf of Finland in accordance with the requirements of regulatory documents. Analysis of the results of hydrochemical studies and their comparison with data on water intakes in adjacent areas gives the right to conclude that it is possible to classify a hydrogeological unit as a different type of resource formation than those located in the surrounding areas. Groundwater in this area is confined to an unexplored deep fractured regional high-pressure zone. According to the received data, the explored water intake can be attributed to a unique groundwater deposit, which has an uncharacteristic composition of groundwater in the north of the Leningrad region, which may be due to the mixing of modern sediments and relict waters of the Baltic glacial lake. The stability of groundwater characteristics is confirmed by long-term monitoring.
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Date submitted2022-03-14
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Date accepted2022-06-20
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Date published2022-11-10
Model of a walking sampler for research of the bottom surface in the subglacial lake Vostok
Technologies and technical means for investigation of subglacial lakes in Antarctic is a new developing scientific and technical direction, which today has no clearly established methodology. Based on the developed technology of drilling a new access well to lake Vostok and its penetration as well as analysis of existing methods and devices for bottom sediment sampling, a basic model of a sampler with a walking-type mover, capable of moving along different trajectories and operating in a wide technological range, is proposed. The proposed device model is equipped with different actuators for sampling the bottom surface with different physical and mechanical properties. Based on the presented basic model of the walking sampler, a mathematical model of the device was developed, which was based on the theoretical mechanics methods. As a result of conducted research the dependencies were obtained, which allow making a scientifically justified choice of optimal values for geometric and force parameters of the walking sampler. A conceptual design of the walking sampler has been developed, taking into account the mutual location and coupling of its main components, the overall dimensions of the delivery tool, as well as the esthetic component of the device.
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Date submitted2021-10-19
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Date accepted2021-11-30
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Date published2021-12-27
Potential technological solution for sampling the bottom sediments of the subglacial lake Vostok: relevance and formulation of investigation goals
The subglacial Lake Vostok in Antarctic is a unique natural phenomenon, its comprehensive study involves sampling of water and bottom surface rocks. For further study of the lake, it is necessary to drill a new access well and develop environmentally safe technologies for its exploration. This article discusses existing and potential technologies for sampling bottom surface rocks of subglacial lakes. All these technologies meet environmental safety requirements and are conducive for sampling. The authors have proposed an alternative technology, using a walking device, which, due to its mobility, enables selective sampling of rocks across a large area from a single access well. The principal issues, related to the implementation of the proposed technology, are investigated within this article. This report is prepared by a team of specialists with many years of experience in drilling at the Vostok Station in Antarctic and in experimental work on the design of equipment and non-standard means of mechanization for complicated mining, geological and climatic conditions.
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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 submitted2016-11-21
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Date accepted2017-01-23
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Date published2017-04-14
Prospects of obtaining samples of bottom sediments from subglacial lake Vostok
- Authors:
- N. I. Vasilev
- G. L. Leichenkov
- E. A. Zagrivnyi
The paper proves the timeliness of obtaining and examining bottom sediments from subglacial Lake Vostok. Predictive geological section of Lake Vostok and information value of bottom sediments have been examined. Severe requirements towards environmental security of lake examinations and sampling of bottom sediments rule out the use of conventional drilling technologies, as they would pollute the lake with injection liquid from the borehole. In order to carry out sampling of bottom sediments from the subglacial lake, it is proposed to use a dynamically balanced tool string, which enables rotary drilling without any external support on borehole walls to transmit counter torque. A theoretical analysis has been carried out to assess the operation of the tool string, which is a two-mass oscillatory electromechanical system of reciprocating and rotating motion (RRM) with two degrees of freedom.
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Date submitted2015-12-08
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Date accepted2016-02-20
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Date published2016-12-23
The ways of transformation of salt production from the saline lakes of Apsheron peninsula
- Authors:
- V. A. Mamedov
- Kh. Kh. Khalilova
The issues of salt production at salt lakes of Apsheron Peninsula in Azerbaijan are reviewed here. The paper objective is to examine the brine formation process and analyze the ways of transformation of salt extraction from the lakes of Apsheron Peninsula under ever increasing industrial development and urbanization. The research on ecological state of salt lakes at the peninsula have shown that the decades-long development of oil and gas and other industries had a dramatical impact on the natural properties of water resources in this area. Laboratory test revealed high concentrations of total hydrocarbons, phenols, toxic metals (Cd, Pb, Zn, Ni, Cu, V, Mo, etc.), surface-active suspended solids and other pollutants in water samples of salt lakes. The paper presents physical and chemical properties of Boyukshore Lake, which for many years was the republic’s primary source of cooking salt. Based on comparative analysis of obtained properties with the maximum allowable concentrations and international standards the level of pollution of natural salt lakes of Apsheron has been assessed and the contribution of each anthropogenic source to the pollution of these water bodies has been determined. The paper presents quantitative and qualitative properties and pictures of the lakes depicting formation of saline deposits and volumes of salt produced at brine lakes of Apsheron. It has been established that decades-long negative impact on the environment led to disruption of ecological balance of the open waters in the region. Most saline lakes in the peninsula lost their natural qualities and became unsuitable for salt production.
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Date submitted2015-08-21
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Date accepted2015-10-24
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Date published2016-04-22
Results of the 5G borehole drilling at russian antarctic station «Vostok» and researches of ice cores
- Authors:
- N. I. Vasilev
- A. N. Dmitriev
- V. Ya. Lipenkov
We produce an information about results and features of the 5G borehole drilling in Antarctic layer at Russian station Vostok. Main regularities of the change structured and physical properties by Antarctic ice layer depth, which determine mechanical and reological properties if ice, which influence to sinking of a borehole and to the maintaining of it in a working condition, the safe and competitive technologies creation for drilling of strong ice layers and the environmentally safe technology of the subglacial reservoirs unsealing. We also produce results of the ice cores researching and the paleoclimatic raws construction, which are reconstructed by the ice cores researching from Vostok station, which is compared with isotopic graph. This graph describes changes of World ocean level.