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Date submitted2022-05-12
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Date accepted2022-11-17
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Date published2023-04-25
Microbiological remediation of oil-contaminated soils
- Authors:
- Irina D. Sozina
- Aleksandr S. Danilov
Microbiological remediation is a promising technology for the elimination of environmental contamination by oil and petroleum products, based on the use of the metabolic potential of microorganisms. The issue of environmental contamination by crude oil and its refined products is relevant in the Russian Federation since the oil industry is one of the leading sectors of the country. Mechanical and physico-chemical methods of treatment are widely used to clean oil-contaminated soils. However, the methods belonging to these groups have a number of significant drawbacks, which actualizes the development of new methods (mainly biological), since they are more environmentally friendly, cost-effective, less labor-intensive, and do not require the use of technical capacities. Various bio-based products based on strains and consortia of microorganisms have been developed that have proven effectiveness. They include certain genera of bacteria, microscopic fungi, and microalgae, substances or materials acting as sorbents of biological agents and designed to retain them in the soil and increase the efficiency of bioremediation, as well as some nutrients. Statistical data, the most effective methods, and technologies, as well as cases of using microorganisms to restore oil-contaminated soils in various climatic conditions are presented.
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Date submitted2018-09-02
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Date accepted2018-10-28
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Date published2019-02-22
Factors affecting bacterial and chemical processes of sulphide ores processing
- Authors:
- T. S. Khainasova
Extraction of valuable components from sulphide ores using microorganisms is a recognized biotechnological method, combining several advantages over traditional methods of mineral processing. This paper presents the main factors affecting the bacterial-chemical leaching and methods of leaching with the participation of microorganisms. Some physical-chemical (temperature, pH, oxygen, carbon dioxide, nutrients, metals and other chemical elements) and microbial (cell count and microflora activity) properties are given, either directly or indirectly (suppressing or contributing to the growth and oxidative capacity of microorganisms) affecting the kinetics of the process. The paper discusses the characteristics of the mineral substrate, including galvanic interaction of sulfide minerals and the formation of passivating layers on the surface of the ore during oxidation, emphasizing the importance of the electrochemical interaction of the components of the leaching system. Bioleaching is a complex process, which is a combination of mainly chemical reactions mediated by the microbial component, therefore, to improve the kinetics, it is necessary to consider, monitor and regulate the listed range of factors.
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Date submitted2015-07-20
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Date accepted2015-09-26
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Date published2016-02-24
Prospects of biotechnologies application in metallurgy and enrichment
- Authors:
- N. M. Telyakov
- A. A. Darin
- V. A. Luganov
In recent years, application of biotechnologies in enrichment processes and processing of metal-containing ores has gained broad development, considering essential advantages of these technologies from the point of view of economic efficiency and ecological safety. Processes with the application the hemolitotrofnykh of acidophile microorganisms of Acidithiobacillus ferrooxidans, At. thiooxidans, Leptospirillum ferrooxidans and others, are of great interest. This article is devoted to the problem of biocultures application for efficiency improvement of the ore pretreatment technology and extraction of valuable components from metal-containing crude ore. The analysis of the biotechnologies and microorganisms applied at domestic and foreign enterprises is given, alongside with the theoretical bases of ore bioprocessing, research results of oxide and sulphidic metal-containing ores processing technology development, with the application of microorganisms and research results of the mechanism of destructive impact of a certain type bacteria on siliceous ores.
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Date submitted2009-08-17
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Date accepted2009-10-12
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Date published2010-02-01
Complex geological engineering and geoenvironmental monitoring as a basis for creation of strategy of Saint Petersburg architectural and historical monuments conservation
- Authors:
- A. V. Shidlovskaya
In the paper concept and structural of complex engineering geological and geoenvironmental monitoring of architectural and historical monuments are considered. The specificity of engineering geological and hydrogeological conditions by the example of the Isaac Cathedral, the Kazan Cathedral and the Peter and Paul Cathedral is analyzed. The geoenvironmental condition of architectural and historical monuments underground space is estimated. The factors which influence on monuments deformation due to the high degree of underground space transformation and activity of negative natural and technogenic processes are shown. The system of impact monitoring of the Isaac Cathedral, the Kazan Cathedral and the Peter and Paul Cathedral is proposed.
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Date submitted2008-10-12
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Date accepted2008-12-17
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Date published2009-12-11
Principles of development of geological engineering and geological criteria for safe burial of low radioactive wastes in lower cambrian blue clays in the Leningrad region
- Authors:
- R. E. Dashko
It is noticed that the chosen territory for nuclear-waste disposal in Lower Cambrian clay massif nearby Koporje of Leningrad region takes place in a tectonic zone. Lower Cambrian clays are considered as the block-fractured rock mass having a depth zone structure. The long radioactive irradiation of dark blue clays has led to transformation of their structure, physical-chemical and physical-mechanical properties, and also to activization of microbial activity. Nine criteria to the geoenvironmental and engineering geological characteristics allowing in a complex to estimate safety and reliability of a nuclear-waste disposal in clay formations on an example of dark blue clays are suggested.