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Vol. 20 (2017 year), No. 1, DOI: 10.21443/1560-9278-2017-20-1/2
Fokina N. V., Yanishevskaya Е. S., Vishnyakova I. N.,
Gershenkop А. Sh., Evdokimova G. А.
Development and functioning of microorganisms
in concentration cycles of sulfide copper-nickel
and non-sulfide apatite-nepheline ores
The number and trophic diversity of bacteria in flotation samples of apatite-nepheline and sulfide copper-nickel ores at the concentration plants of JSC "Apatite" and Kola Mining and Metallurgical Company have been determined. The study of the size and diversity of the microbiota has been conducted by culture on selective nutrient media. The total number and biomass of bacteria have been considered by fluorescence microscopy using Cyclopore polycarbonate membrane filters. Bacteria have been identified by molecular genetic methods. The least amount of both saprotrophic and other trophic groups of bacteria has been observed in the samples of ore and recycled water as at the concentrating factory of Apatit JSC, and also at the plant "Pechenganikel". It has been found out that the bacteria contained in the ore and recycling water flowing from the tailings increased their number during the flotation process due to coming of the nutrients with the flotation reagents, aeration and increased temperature. Strains which occurrence is more than 60 % have been extracted from recycled water and basic flotation products and classified as Pseudomonas. Two strains with occurrence of more than 60 % have been discovered at Apatit JSC and classified as Stenotrophomonas and Acinetobacter. The number of fungi in the cycle of apatite-nepheline ore enrichment at the factories is very low (1 to 24 CFU / 1 ml or 1 g of ore). Fungi of the genus Penicillium have been dominated, fungi of the genera Acremonium, Aureobasidium, Alternaria, Chaetomium have also been detected. At the plant "Pechenganikel" species Aspergillus fumigatus, Penicillium aurantiogriseum and P. glabrum have been extracted. It has been shown that the bacteria deteriorate the apatite flotation as a result of their interaction with active centers of calcium-containing minerals and intensive flocculation decreasing the floatation selectivity. Also some trend of copper and nickel recovery change has been detected with the presence of a high number of bacteria
(in Russian, стр.7, fig. 3, tables. 2, ref 6, Adobe PDF, Adobe PDF 0 Kb)
Vol. 21 (2018 year), No. 1, DOI: 10.21443/1560-9278-2018-21-1
Fokina N. V., Yanishevskaya E. S., Svetlov A. V., Goryachev A. A.
Functional activity of microorganisms in mining and processing of copper-nickel ores in the Murmansk Region
The quantitative indices and structure of the microbial community in flotation samples of sulfide copper-nickel ores at concentration plant of Kola Mining and Metallurgical Company have been determined. The smallest number of saprotrophic and oligotrophic bacteria has been observed in samples of ore and recycled water, which can be explained by the low temperature of samples and the lack of nutrients. It has been found out that the bacteria contained in the ore and recycling water flowing from the tailings increased their number during the flotation process due to coming of the organic compounds with the flotation reagents, aeration and increased temperature. Dominating strains have been isolated from recycled water and basic flotation products and classified as Pseudomonas. It has been shown that with an increase in the number of bacteria, the flotation time of copper-nickel ores increases. There is also a tendency to change the extraction of copper and nickel, which can be caused by both the increase in the flotation time for operations and the change in the number of bacteria in the circulating water. The thionic bacteria have been distinguished from the flow tailings of the Allarechensk deposit. The heap leaching experiments have proved the bacterial leaching to give good results on the ore samples passed through magnetic separation, having shown high content of the nickel and copper in filters. When leaching low-grade ore of the Nude Terrasa, the advantage of bacterial leaching use in comparison with the sulphuric-acid leaching only to copper has been revealed. The nickel content in the filtrates for bacterial leaching is 275 mg/l, and for sulfuric acid – 310 mg/l. The average copper content in the filtrates is 19 and 15 mg/l.
(in Russian, стр.7, fig. 2, tables. 1, ref 12, adobe PDF, adobe PDF 0 Kb)
Vol. 22 (2019 year), No. 1, DOI: 10.21443/1560-9278-2019-22-1
Studies on the effectiveness of the using aluminosilicate mineral vermiculite of various modifications as a sorbent for the purification of natural media from petroleum products have been carried out. It has been shown that the treatment of the sorbent with a hydrophobic modifier "Penta-804" makes it possible to obtain the hydrophobic sorbent, which has high water resistance, it is able to be retained for a long time on the water surface and is nontoxic for biota. The highest efficiency is demonstrated by sorbents, on the surface of which the strains of the aboriginal oil-destructive bacteria Pseudomonas spp. have been immobilized. They allow achieving a high degree of purification (99.8 %). A high degree of water purification with covalent cross-linking sorbent (76.26 %) and bacterial suspension (51.34 %) has been also noted. Due to the desorption processes the use of sorbents for a long time is inadvisable. The use of vermiculite sorbent by scattering on the water surface proved to be more effective than in mats, which is associated with a more complete coating of the contamination surface. So, the degree of surface cleaning using the sorbent by scattering is 95 %, while the degree of surface cleaning using sorbent in mats is 78 %. In this case, the use of sorbent in mats allows reducing the percentage of particles settling to zero, and mats remain afloat for a longer time. After application in the purification process, the sorbent can be burned, modified and reused. Modified hydrophobic vermiculite in mats can be used only at the initial stages of soil purification in case of significant oil spills. Hydrophilic sorbents can perform the function of loosening the soil, improving its mechanical properties, and serve as a carrier for hydrocarbon oxidizing microorganisms
(in Russian, стр.8, fig. 4, tables. 3, ref 15, Adobe PDF, Adobe PDF 0 Kb)
Vol. 27 (2024 year), No. 1, DOI: 10.21443/1560-9278-2024-27-1
Myazin V. A., Shushkov D. A., Fokina N. V., Chaporgina A. A., Kanivets A. V., Bryantsev A. V.
Effectiveness of biogeosorbents based on mineral carriers for treatment oil-contaminated soil
Methods for cleaning oil-contaminated areas include the use of sorbents, the effectiveness of which is enhanced by the immobilization of hydrocarbon-oxidizing microorganisms on their surface. Biogeosorbents are obtained on the basis of mineral raw materials (analcime- and glauconite-containing rocks and thermally activated vermiculite) and hydrocarbon-oxidizing bacteria of the genera Pseudomonas and Microbacterium extracted from contaminated soils of the Murmansk region. The number of immobilized bacteria on the studied carriers remains high throughout 9 months of storage, and the bacterial film on the surface of mineral carriers persists for 12 months of storage in an air-dry state. When storing biogeosorbents, no special conditions or additional preparation are required before use. Mineral carriers have a stimulating effect on the height of seedlings and the length of roots of test plants. When biogeosorbents are added, the number of bacteria capable of microbiological transformation of petroleum products increases, and the degree of soil purification from petroleum hydrocarbons at the initial stage (during the first 30 days) increases. The most effective is the introduction of thermally activated vermiculite and glauconite-containing rock with immobilized hydrocarbon-oxidizing bacteria. The use of a biogeosorbent based on thermally activated vermiculite can reduce the cleaning time to 20–22 months, and based on glauconite-containing rock – up to 17 months, while without treatment this period will be at least 29 months.
(in Russian, стр.11, fig. 7, tables. 2, ref 27, AdobePDF, AdobePDF 0 Kb)