scholarly journals STATE OF WATER BODIES IN THE AREA OF INFLUENCE OF MINING AND PROCESSING ENTERPRISES (CASE STUDY OF LOVOZERSKY MINING AND PROCESSING PLANT)

2021 ◽  
Vol 26 (2) ◽  
pp. 3-13
Author(s):  
E. A. Krasavtseva ◽  
◽  
S. S. Sandimirov ◽  
Keyword(s):  
Rare Earth ◽  
Chemical Composition ◽  
Rare Earth Elements ◽  
Bottom Sediments ◽  
Surface Waters ◽  
Pollution Index ◽  
Water Bodies ◽  
Processing Plant ◽  
Background Values ◽  
Murmansk Region

Introduction. This extended study is the first to analyze the chemical composition of the surface waters and bottom sediments of the lakes affected to various extents by Lovozersky Mining and Processing Plant (Revda urban settlement, Murmansk Region) performing mining and processing of rare metal ores. Methods. During the study, we used data obtained in the course of research in 1995–2005 and 2019–2020. Water and bottom sediment samples were analyzed using various methods. The total contents of elements in the bottom sediments were compared with the background values or, in their absence, with the clarke contents of elements in the Earth’s crust. To assess the level of pollution in the Sergevan River receiving wastewater from the plant, the maximum pollution index was calculated. Results. Over the past 35 years, the chemical composition of the surface waters of nearby water bodies underwent minor changes. No significant excess of maximum permissible concentrations for fishery water bodies was found. The comparison of the contents of heavy metals in the bottom sediments collected from Lakes Ilma and Krivoye with the background values revealed contamination of the Lake Ilma with strontium, zinc and manganese. Besides, a multiple excess of the content of rare earth elements (La, Ce, Pr, Nd), Nb and Ta was established in the bottom sediments of Lake Ilma in comparison with that in Lake Krivoye. The analysis of the river water samples taken at different distances upstream and downstream the site of wastewater discharge confirmed the assumption about the pollution of the Sergevan River by wastewater from the plant. Conclusion. The pollution of the water bodies is mainly caused by wastewater discharged from the plant, however, the increased content of rare earth elements in the bottom sediments of Lake Ilma may be due to air transport of particles of loparite ore concentration tailings, drainage from tailing dams, or degradation of underlying rocks.

scholarly journals Causes of variations of trace and rare earth elements concentration in lakes bottom sediments in the Bory Tucholskie National Park, Poland

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Mariusz Sojka ◽  
Adam Choiński ◽  
Mariusz Ptak ◽  
Marcin Siepak
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Spatial Variability ◽  
Bottom Sediments ◽  
National Park ◽  
Anthropogenic Sources ◽  
Geochemical Processes ◽  
Natural Processes ◽  
Sources Of Pollution ◽  
Geochemical Indices

AbstractThe objective of this study was to analyse spatial variability of the trace elements (TEs) and rare earth elements (REEs) concentration in lake bottom sediments in Bory Tucholskie National Park (BTNP); Poland. The following research questions were posed: which factors have a fundamental impact on the concentration and spatial variability of elements in bottom sediments, which of the elements can be considered as indicators of natural processes and which are related to anthropogenic sources. The research material was sediments samples collected from 19 lakes. The concentrations of 24 TEs and 14 REEs were determined. The analyses were carried out using the inductively coupled plasma mass spectrometry (ICP-QQQ). Cluster analysis and principal component analysis were used to determine the spatial variability of the TEs and REEs concentrations, indicate the elements that are the indicators of natural processes and identify potential anthropogenic sources of pollution. The geochemical background value (GBV) calculations were made using 13 different statistical methods. However, the contamination of bottom sediments was evaluated by means of the index of geo-accumulation, the enrichment factor, the pollution load index, and the metal pollution index. The BTNP area is unique because of its isolation from the inflow of pollutants from anthropogenic sources and a very stable land use structure over the last 200 years. This study shows high variability of TE and REE concentrations in lake sediments. The values of geochemical indices suggest low pollution of lakes bottom sediments. It was found that TEs originated mainly from geogenic sources. However, the concentrations of Li, Ni, Sc, Se, Be, Se, Ag, Re, Tl, Cd, Sb and U may be related to the impact of point sources found mainly in the Ostrowite Lake. Almost all REEs concentrations were strongly correlated and their presence was linked to with geochemical processes. The elements allowing to identify natural processes and anthropogenic pollution sources were Cr, Co, Cu, Ag, Cd, Zn, Bi, Re, Ba, Al and Rb in TEs group and Nd, Gd, Yb, Lu, Eu, Dy and Ce in REEs group. The analysis shows high spatial variability of TE and REE concentrations in lake sediments. The values of geochemical indices point to low pollution of lakes sediments. The anthropogenic sources only for two lakes had an impact on concentrations of selected TEs and REEs. The analyses allowed to identify elements among TEs and REEs documenting geochemical processes and those indicating anthropogenic sources of pollution.

scholarly journals Modification of Non-Metallic Inclusions by Rare-Earth Elements in Microalloyed Steels

2012 ◽  
Vol 12 (2) ◽  
pp. 129-134 ◽  
Author(s):  
M. Opiela ◽  
A. Grajcar
Keyword(s):  
Rare Earth ◽  
Chemical Composition ◽  
Rare Earth Elements ◽  
Mechanical Treatment ◽  
Induction Furnace ◽  
Microalloyed Steels ◽  
Metallurgical Process ◽  
Metallic Inclusions ◽  
Mean Size ◽  
Thermo Mechanical Treatment

Modification of Non-Metallic Inclusions by Rare-Earth Elements in Microalloyed Steels The modification of the chemical composition of non-metallic inclusions by rare-earth elements in the new-developed microalloyed steels was discussed in the paper. The investigated steels are assigned to production of forged elements by thermo-mechanical treatment. The steels were melted in a vaccum induction furnace and modification of non-metallic inclusions was carried out by the michmetal in the amount of 2.0 g per 1 kg of steel. It was found that using material charge of high purity and a realization of metallurgical process in vacuous conditions result in a low concentration of sulfur (0.004%), phosphorus (from 0.006 to 0.008%) and oxygen (6 ppm). The high metallurgical purity is confirmed by a small fraction of non-metallic inclusions averaging 0.075%. A large majority of non-metallic inclusions are fine, globular oxide-sulfide or sulfide particles with a mean size 17 μm2. The chemical composition and morphology of non-metallic inclusions was modified by Ce, La and Nd, what results a small deformability of non-metallic inclusions during hot-working.

Rare earth elements in bottom sediments of major rivers around the Yellow Sea: implications for sediment provenance

2009 ◽  
Vol 29 (5) ◽  
pp. 291-300 ◽  
Author(s):  
Zhaokai Xu ◽  
Dhongil Lim ◽  
Jinyong Choi ◽  
Shouye Yang ◽  
Hoisoo Jung
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Bottom Sediments ◽  
Yellow Sea ◽  
The Yellow Sea ◽  
Sediment Provenance

scholarly journals Geochemical Characterization and Presence of Rare Earth Elements in the Recent Depositions at the Islands of the Eastern Bay of Bengal, Bangladesh

2020 ◽  
Vol 11 (1) ◽  
pp. 40-47
Author(s):  
Farah Deeba ◽  
Syed Hafizur Rahman ◽  
Mohammad Zafrul Kabir ◽  
Mohammad Rajib
Keyword(s):  
Rare Earth ◽  
Chemical Composition ◽  
Rare Earth Elements ◽  
Bay Of Bengal ◽  
Heavy Mineral ◽  
Heavy Minerals ◽  
Mineral Concentration ◽  
Near Surface ◽  
Geochemical Characterization ◽  
X Ray

This study presents geochemical characterization, as well as, quantification of rare earth elements in the recent beach deposition at the two major islands of the eastern Bay of Bengal-Kutubdia and Moheshkhali. Placer sand samples from near surface depositions were analyzed by heavy mineral separation, mineralogical identification, chemical composition and elemental mapping. X-ray diffraction (XRD), X-ray fluorescence (XRF), Scanning Electron Microscopy with Energy Dispersive Spectroscopy (SEM-EDS) were used to obtain these results. The heavy mineral concentration in different raw sand samples resulted by heavy liquid separation technique revealed that the average abundance of heavy minerals is 69.67% in Kutubdia island and 9.32% in Moheshkhali island, respectively. The X-ray patterns of Kutubdia and Moheshkhali sand samples show the presence of zircon, quartz, hematite, magnetite, ilmenite, chromite, kyanite, anatase, rutile and garnet. Chemical composition of heavy mineral sands from Kutubdia and Moheshkhali islands were analyzed using X-ray fluorescence method (XRF) for major oxides and trace elements. The concentration is of Na2O, MgO, Al2O3, SiO2, P, K2O, CaO, TiO2, V2O5, Cr2O3, MnO, Fe2O3, CoO, ZnO, SrO, Y2O3 ZrO2, Nb2O5, MoO3, HfO2, WO3, ThO2, U3O8, CeO2, Nd2O and Er2O3 were determined. A significant amount of various rare earth elements (REEs) in the elemental composition of few samples was also identified. The study is expected to be useful in the baseline and environmental aspects of both the islands.

scholarly journals Brown coals of Far East – natural resource for multipurpose industrial processing

2018 ◽  
Vol 56 ◽  
pp. 03018
Author(s):  
Anatoliy Sorokin ◽  
Andrey Konyushok
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Economic Value ◽  
Far East ◽  
Processing Plant ◽  
Chemical Processing ◽  
Rare Metals ◽  
Standard Facility ◽  
Industrial Processing ◽  
Brown Coals

The analysis of the potential economic value of brown coals of the Far East of Russia is carried out when to use them as a complex chemical mineral resource. It was conducted assessment of industrial attractiveness to use coal combustion or coal chemical processing wastes as an additional source of gold, rare metals and rare earth elements. The Sergeevskoye brown coal deposit of the Zeya-Bureya Sedimentary Basin in the Amur Region was proposed as a potential standard facility for the construction of a coal-chemical processing plant to produce resin, montan wax, complex hydrocarbons with associated gold, rare metals and rare earth elements recovery.

Spatial distribution of the sediments in the Gangkou River catchment: Evidence from chemical composition, rare earth elements, and lead isotopes

2021 ◽  
Author(s):  
Hung-Chun Chao
Keyword(s):  
Rare Earth ◽  
Chemical Composition ◽  
Rare Earth Elements ◽  
Lead Isotopes ◽  
Sediment Geochemistry ◽  
Beach Sediment ◽  
River Catchment ◽  
Core Samples ◽  
Beach Sediments ◽  
High Terrace

<p>    Sediment geochemistry has been widely used to indentify the source of the sediments delivered from catchment to the deposition basin.  In this study, bed load sediments, high terrace soils, beach sediments, and cores drilled at estuary were collected at the catchment of Gangkou River and its tributary, Linlu River, southern Taiwan.  All sediments were sieved by 0.062 μm sifter and exchangeable, carbonate, and iron oxide phases were leached and only residue silicate phase were digested.  Chemical composition, rare earth elements (REEs), and lead isotopes were measured.  The results show that two major catchments, Linlu River and Gangkou River, as well as high terrace soil and beach sediments can be successfully classified by chemical composition and lead isotopes.  However, REEs show signature of upper continental crust and no differences among all the samples, possibly due to the same source of high REEs minerals.  The characteristic of chemical composition and lead isotopes are different between two catchments and the estuary sediments as well as beach sediments near the estuary imply mixing behavior between two catchments.  The upper most of the estuary core samples, presented as modern sediment, have similar chemical composition and lead isotopes compared with the mainstream.  However, the beach sediment on the top of the dune and the lower part of the core samples, which are elder than 7 ka, have distinct chemical and isotopic characteristics, indicating different sediment sources.  In, summary, chemical composition and the lead isotopes are robust tracers for the leached fine sediments in Gangkou River catchment but REEs are not.  The results of estuary core indicate that the sediment source of the estuary before 7 ka is different from the present.</p>

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