scholarly journals Geochemistry, Mineralogy and Microbiology of Cobalt in Mining-Affected Environments

Minerals ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 22
Author(s):  
Gabriel Ziwa ◽  
Rich Crane ◽  
Karen A. Hudson-Edwards
Keyword(s):  
Mine Waste ◽  
Modern Technology ◽  
Ore Deposits ◽  
Raw Material ◽  
Knowledge Gaps ◽  
Mining Operations ◽  
Environmental Transformation ◽  
Ph Conditions ◽  
High Concentrations ◽  
Co Precipitation

Cobalt is recognised by the European Commission as a “Critical Raw Material” due to its irreplaceable functionality in many types of modern technology, combined with its current high-risk status associated with its supply. Despite such importance, there remain major knowledge gaps with regard to the geochemistry, mineralogy, and microbiology of cobalt-bearing environments, particularly those associated with ore deposits and subsequent mining operations. In such environments, high concentrations of Co (up to 34,400 mg/L in mine water, 14,165 mg/kg in tailings, 21,134 mg/kg in soils, and 18,434 mg/kg in stream sediments) have been documented. Co is contained in ore and mine waste in a wide variety of primary (e.g., cobaltite, carrolite, and erythrite) and secondary (e.g., erythrite, heterogenite) minerals. When exposed to low pH conditions, a number of such minerals are known to undergo dissolution, typically forming Co2+(aq). At circumneutral pH, such aqueous Co can then become immobilised by co-precipitation and/or sorption onto Fe and Mn(oxyhydr)oxides. This paper brings together contemporary knowledge on such Co cycling across different mining environments. Further research is required to gain a truly robust understanding of the Co-system in mining-affected environments. Key knowledge gaps include the mechanics and kinetics of secondary Co-bearing mineral environmental transformation, the extent at which such environmental cycling is facilitated by microbial activity, the nature of Co speciation across different Eh-pH conditions, and the environmental and human toxicity of Co.

scholarly journals A Geometallurgical Approach to Tailings Management: An Example from the Savage River Fe-Ore Mine, Western Tasmania

Minerals ◽  
2018 ◽  
Vol 8 (10) ◽  
pp. 454 ◽  
Author(s):  
Anita Parbhakar-Fox ◽  
John Glen ◽  
Bonita Raimondo
Keyword(s):  
Mine Waste ◽  
Mineral Chemistry ◽  
Cobalt Hydroxide ◽  
Tailings Dam ◽  
Total Oxidation ◽  
Controlling Parameter ◽  
Tailings Management ◽  
Pyrite Concentrate ◽  
High Concentrations ◽  
Co Precipitation

At the Old Tailings Dam (OTD), Savage River, Western Tasmania, 38 Mt of pyritic tailings were deposited (1967 to 1982) and have since been generating acid and metalliferous drainage (AMD). Mineral chemistry analysis confirmed high concentrations of refractory cobalt in pyrite (up to 3 wt %). This study sought to determine, through a series of bench scale tests, if Co could be liberated using biohydrometallurgical techniques. Four bulk tailings samples were collected across the OTD, from up to 1.5 m depth, targeting three sulphide-bearing facies. The study was conducted in four stages: (1) bacterial adaption using BIOX® bacteria; (2) biooxidation optimization with pH, temperature and Fe medium parameters tested; (3) flotation test work to produce a sulphide concentrate followed by biooxidation; and (4) Fe and Co precipitation tests. The BIOX® culture adapted to the bulk composite (containing 7 wt % pyrite) in ~10 days, with biooxidation occurring most efficiently at pH 1.5–1.6 and 40 °C whilst the Fe medium concentration was identified as a less-controlling parameter. Flotation produced a 71% pyrite concentrate with total oxidation occurring after 14 days of biooxidation with 99% of Co leached. At pH 3, Co was effectively separated from Fe, however Ni and Cu were also present in the pregnant liquor solution and therefore required refining before production of cobalt hydroxide, the intermediate saleable product. This study shows that adopting a geometallurgical approach to tailings characterisation can identify if mine waste has commodity potential and how best to extract it therefore unlocking the potential for unconventional rehabilitation of AMD affected sites.

scholarly journals First-Time Source Apportionment Analysis of Deposited Particulate Matter from a Moss Biomonitoring Study in Northern Greece

Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 208 ◽  
Author(s):  
Chrysoula Betsou ◽  
Evangelia Diapouli ◽  
Evdoxia Tsakiri ◽  
Lambrini Papadopoulou ◽  
Marina Frontasyeva ◽  
...  
Keyword(s):  
Source Apportionment ◽  
Power Plants ◽  
Soil Dust ◽  
Northern Greece ◽  
Mining Operations ◽  
Moss Species ◽  
Elemental Concentrations ◽  
Pmf Model ◽  
Moss Biomonitoring ◽  
High Concentrations

Moss biomonitoring is a widely used technique for monitoring the accumulation of trace elements in airborne pollution. A total of one hundred and five samples, mainly of the Hypnum cupressiforme Hedw. moss species, were collected from the Northern Greece during the 2015/2016 European ICP Vegetation (International Cooperative Program on Effects of Air Pollution on Natural Vegetation and Crops) moss survey, which also included samples from the metalipherous area of Skouries. They were analyzed by means of neutron activation analysis, and the elemental concentrations were determined. A positive matrix factorization (PMF) model was applied to the results obtained for source apportionment. According to the PMF model, five sources were identified: soil dust, aged sea salt, road dust, lignite power plants, and a Mn-rich source. The soil dust source contributed the most to almost all samples (46% of elemental concentrations, on average). Two areas with significant impact from anthropogenic activities were identified. In West Macedonia, the emissions from a lignite power plant complex located in the area have caused high concentrations of Ni, V, Cr, and Co. The second most impacted area was Skouries, where mining activities and vehicular traffic (probably related to the mining operations) led to high concentrations of Mn, Ni, V, Co, Sb, and Cr.

Ceramic Proppants Based on Ultrabasic Rocks of Kazakhstan Chromite Ore Deposits

2019 ◽  
Vol 946 ◽  
pp. 169-173
Author(s):  
A.A. Biryukova ◽  
T.D. Dzhienalyev ◽  
A.V. Boronina
Keyword(s):  
Oil And Gas ◽  
Mineralogical Composition ◽  
Magnesium Silicate ◽  
Gas Production ◽  
Ore Deposits ◽  
Raw Material ◽  
Chrome Spinel ◽  
Overburden Rock ◽  
Oil And Gas Production ◽  
Silicate Ceramic

The purpose of the work is the obtaining of magnesium silicate ceramic proppants, based on ultrabasic overburden rocks of Kempirsai deposits of chromite ores (Kazakhstan). The chemical and mineralogical composition of ultrabasic overburden rock was studied by chemical, microscopic and X-ray diffraction analyzes. It is established that the main mineral of ultrabasic overburden rocks is serpentine, present in the form of fibrous chrysotile and lamellar antigorite. In the impurities are iron oxides and hydroxides, chrome spinel, carbonates, quartz. Assessment of the use of overburden rocks as a raw material for the production of ceramic proppants was carried out. The sintering interval of overburden rocks was determined at 1280-1300 °C. The sintering firing optimum temperature of ceramics, based on this type of raw material is 1300 °C. It is established that to harden the structure of magnesium silicate ceramic it is necessary to activate the raw material thermally at a temperature of 1000 °C. The influence of binder type on the properties of magnesium silicate proppants, based on the Kempirsai serpentinites was studied. Magnesium silicate proppants, based on ultrabasic overburden rocks, were obtained with the following properties: apparent density – 1.6 g/cm3, strength resistance (52 MPa) – 14%, sphericity and roundness – 0.8; chemical resistance (hydrochloric acid) – 98%, static strength of the fraction 16/20 - 72–118 N/granule. The field of application is oil and gas production, metallurgy and ceramic industries.

Upshot of Concentration of Zirconium (IV) Oxynitrate Hexa Hydrate on Preparation and Analyses of Zirconium Oxide (ZrO2) Nanoparticles by Modified Co-Precipitation Method

2021 ◽  
Vol 21 (11) ◽  
pp. 5707-5713
Author(s):  
M. Ramachandran ◽  
R. Subadevi ◽  
P. Rajkumar ◽  
R. Muthupradeepa ◽  
R. Yuvakkumar ◽  
...  
Keyword(s):  
Ionic Conductivity ◽  
Complex Impedance ◽  
Impedance Analysis ◽  
Raw Material ◽  
Precipitation Method ◽  
Zro2 Nanoparticles ◽  
Fixed Amount ◽  
Complex Impedance Analysis ◽  
Dta Analysis ◽  
Co Precipitation

In the present work, pure nanocrystalline monoclinic Zirconia (ZrO2) has been successfully synthesized and optimized by the modified co-precipitation method. The concentration of raw material has been optimized with the fixed amount of precipitation agent (Potassium hydroxide KOH). The thermal history of the precursor has been examined through TG/DTA analysis. All the samples are subjected to study the structure, fingerprints of the molecular vibrations, and morphology analyses. The representative sample has been analyzed through Transmission Electron Microscope (TEM) and X-ray Photo Electron Spectroscopy (XPS) analyses. The as-prepared sample exhibits the better crystallinity and surface morphology with lesser particle size (190 nm) when the raw material concentration is 0.2 M. The as-prepared ZrO2 filler (0, 3, 6, 9, and 12 wt.%) is spread through the enhanced polymer electrolyte P(S-MMA) (27 Wt.%)-LiClO4 (8 wt.%)-EC + PC (1;1 of 65 wt.%) complex system via solution casting method. The as-synthesized electrolyte films are examined via complex impedance analysis. P(S-MMA) (27 wt.%)-LiCIO4 (8 wt.%)-EC + PC (1 ;1 of 65 wt.%)-6 wt.% of ZrO2 shows the high ionic conductivity 2.35 × 10–3 Scm–1. Temperature-dependent ionic conductivity studies obey the non-linear behavior. The enhanced ZrO2 has been expected to enhance the other electrochemical properties of the lithium secondary battery.

scholarly journals Technogenic wastes and ecological problems

2020 ◽  
Vol 3 ◽  
pp. 61-65
Author(s):  
Anvar Aliyev ◽  
Keyword(s):  
Land Reclamation ◽  
Surface Mining ◽  
Ore Deposits ◽  
Raw Material ◽  
Historical Period ◽  
Administrative District ◽  
Technogenic Contamination ◽  
The Republic ◽  
Lesser Caucasus ◽  
Technogenic Wastes

The northeastern part of the Lesser Caucasus encompasses the western part of the Republic of Azerbaijan and is characterized with a prevalence of unique flora and fauna and the availability of rich natural resources, particularly metals. It is known that the long-term exploitation of these resources by surface mining has led to technogenic contamination in the area. Exploitation of ore deposits is associated with the origination of huge hills of waste which cause heavy degradation of pastures, forests, and croplands. A significant part of widely degraded areas in the northeastern Lesser Caucasus is found in the territory of the Gedabek administrative district. This paper deals with the problem of restoration for contaminated lands formed due to raw material extraction on territory of valuable mountain forests and meadows over a long historical period as well as the use of collected technogenic wastes for different purposes (e.g. in land reclamation, construction of motorways etc.).

scholarly journals Influence of licopine content in tomatoes on taste qualities of canned goods

2020 ◽  
Vol 62 (5) ◽  
pp. 116-122
Author(s):  
Saida S. Saidova ◽  
Keyword(s):  
Antioxidant Properties ◽  
Food Products ◽  
Climatic Conditions ◽  
Raw Material ◽  
Technical Documentation ◽  
Tomato Fruits ◽  
Duration Of Storage ◽  
Tomato Products ◽  
High Concentrations ◽  
The Impact

The article provides a review of world data on the characteristics of the chemical composition of tomato fruits and the impact on their quality of the soil and climatic conditions of cultivation, varietal characteristics and maturity. It is noted that the current regulatory and technical documentation in the Russian Federation does not provide for the determination of functional substances. It has been shown that tomato fruits are a promising plant-growing raw material for the production of functional food products and directions for obtaining lycopene-containing products, canned foods, in particular, from tomato fruits, have been determined. The types of canned food and tomato products containing the highest concentrations of lycopene have been established. The regularity of increasing the concentrations of lycopene in tomato products with various methods of heat treatment is substantiated. The irreplaceable physiological significance of lycopene for the human body is proved, due to its antioxidant properties and the lack of the possibility of its synthesis. The biochemical nature of lycopene as a carotenoid and pigment is analyzed. The progressive foreign technologies of tomato processing have been studied, allowing to reduce the economic costs of production, increase the duration of storage of products containing extremely high concentrations of lycopene. The necessity of developing domestic food products of physiological importance, available for consumption in baby and diet food, is substantiated. It is proved that the Republic of Dagestan has a high climatic and resource potential for growing hybrid varieties of tomatoes containing high concentrations of lycopene and the mass fraction of dry matter necessary for the rational production of canned tomatoes.

The Use of Edible Plants for Rhizofiltration under Different Hydroponic Conditions

2021 ◽  
Author(s):  
juyeon Lee ◽  
minjune Yang
Keyword(s):  
Raphanus Sativus ◽  
Brassica Campestris ◽  
Solid Phase ◽  
Root Surface ◽  
Edible Plants ◽  
Groundwater Samples ◽  
Ph Conditions ◽  
Uranium Accumulation ◽  
High Concentrations ◽  
Hydroponic Conditions

<p>This study conducted a rhizofiltration experiment for uranium-removal with the edible plants (<em>Lactuca sativa, Brassica campestris </em>L., <em>Raphanus sativus </em>L., and <em>Oenanthe javanica</em>) which generally consumed in South Korea. Various batch experiments were performed with different initial uranium concentrations, pH conditions, and genuine groundwater. The results showed the uranium accumulation and bioconcentration factor (BCF) of plant roots increase with an increase in initial uranium concentrations in the solution. Of the four plants, the amount of uranium accumulated in <em>Raphanus sativus </em>L. roots was 1215.8 μg/g DW with the maximum BCF value of 2692.7. The BCF value based on various pH conditions (pHs 3, 5, 7 and 9) of artificial solutions was highest at pH 3 for all four plants, and the BCF value of <em>Brassica campestris </em>L. was the maximum of 11580.3 at pH 3. As a result of rhizofiltration experiments with genuine groundwater contaminated with uranium, the BCF values of <em>Raphanus sativus </em>L. were 1684.7 and 1700.1, the highest among the four species, in Oesam-dong and Bugokdong groundwater samples with uranium concentration of 83 and 173 μg/L. From SEM/EDS analysis, it was confirmed that uranium in contaminated groundwater was adsorbed as a solid phase on the root surface. These results demonstrate that <em>Raphanus sativus </em>L. not only has a high tolerance to high concentrations of uranium and low pH conditions but also has a remarkable potential for uranium accumulation capacity.</p>

Mining, Economy, and Society

2014 ◽  
Author(s):  
William O'Brien
Keyword(s):  
Stone Tools ◽  
Ore Deposits ◽  
Raw Material ◽  
Complex Life Cycle ◽  
Regional Economies ◽  
Primary Metal ◽  
Alloy Type ◽  
Scientific Analysis ◽  
Wealth Generation ◽  
The Impact

The opening chapter of this book considered different factors that influenced the availability of copper resources in prehistory. While geological distribution and technological expertise were critical, consideration must also be given to the wider societal context of production. The operation of early mines must be explained in terms of access to ore deposits and the desire and ability of different population groups to become involved in primary metal production. The impact on local and regional economies is also relevant, in terms of wealth generation through trade and the repercussions for society as a whole. Understanding the organization of this activity is a challenge. Key elements of the chaîne opératoire are often missing, such as the location of smelting sites or the workshops where objects were made. This makes it difficult to establish links between mines and the circulation of intermediate and final metal products in a wider settlement context. With stone tools it is possible to apply production indices to quantify the different stages involved in the use of a specific raw material, with a view to modelling a lithic production system in space (see Ericson 1984). This approach cannot be easily applied to metal objects, which generally have a more complex life cycle than stone tools. This began with a fundamentally different use of a raw material to create a finished object, requiring chemical as well as physical transformation. For this reason, scientific analysis of prehistoric metalwork is problematic in terms of source provenancing to specific ore deposits and mines. There is the further complication of recycling, which in some instances involved the mixing of metal from different mine sources. One approach has been to identify metal circulation zones where copper of a similar chemistry, lead isotope signature, and/ or alloy type was used (e.g. Northover 1982). Within these circulation zones various patterns of primary and secondary (recycled) metal use can be explored in the context of local workshop traditions. This provides a spatial and typochronological context in which to view the input of metal from particular mines.

scholarly journals Application of Cost Reduction Tools in Manufacturing Organizations at Pokhara

2018 ◽  
Vol 6 ◽  
pp. 45-59
Author(s):  
Devilal Sharma
Keyword(s):  
Cost Reduction ◽  
Modern Technology ◽  
Interdisciplinary Studies ◽  
Product Line ◽  
Raw Material ◽  
Primary Data ◽  
Manufacturing Firm ◽  
Two Samples ◽  
Manufacturing Organizations ◽  
Pokhara Valley

Today’s business organization’s success highly depends upon the satisfaction of customer needs and wants since it become the age of globalization. All the manufacturing organizations of Pokhara valley are needed to mass customize their product as the requirement of the customer and satisfy to their needs and wants. For this purpose, organizations have to use the modern technology. This study aims to evaluate the application of cost reduction tools in Nepalese manufacturing organizations with reference to Pokhara valley. Out of total manufacturing firm, only 10 organizations have been selected at least two samples from each stratum out of the target population. Primary data have been collected through the structured questionnaires by distributing it to the production manager or finance manager of the concerned organization. The information has been collected through unit visits. An empirical investigation has been conducted in order to find out various aspects of cost reduction tools. The major tool used for this purpose is the questionnaire. Nepalese manufacturing organizations are selecting the purchase of raw material, production planning and control as the area of reducing their cost. All of the organizations are conscious about TQM as the technique of cost reduction. Most of the organizations are applying product line rationalization, supply chain management, KAIZEN system, reengineering as the technique of cost reduction. Most of the organizations are not applying the Design for manufacturability and concurrent engineering, on demand lean production, build to order, part standardization, Just in Time production system as the tools of cost reduction. Janapriya Journal of Interdisciplinary Studies, Vol. 6 (December 2017), page: 45-59

scholarly journals Pennisetum sinese: A Potential Phytoremediation Plant for Chromium Deletion from Soil

2020 ◽  
Vol 12 (9) ◽  
pp. 3651
Author(s):  
Xiaofei Chen ◽  
Jianhua Tong ◽  
Yi Su ◽  
Langtao Xiao
Keyword(s):  
Biomass Energy ◽  
Raw Material ◽  
Chromium Removal ◽  
High Accumulation ◽  
Chromium Vi ◽  
Livestock Feed ◽  
Low Concentrations ◽  
Plantlet Growth ◽  
Mushroom Culture ◽  
High Concentrations

Chromium is one of the major pollutants in water and soil. Thus, it is urgent to develop a new method for chromium removal from the environment. Phytoremediation is a promising approach for heavy metal pollution recovery. As a perennial giant grass with a fast growth rate, Pennisetum sinese has been widely used as livestock feed, mushroom culture medium and biomass energy raw material. Interestingly, we have found a high adsorption capacity of P. sinese for chromium. P. sinese was treated with different concentrations of chromium for 15 days. Results showed that P. sinese plantlets grew well under low concentrations (less than 500 μM) of chromium (VI). The plantlet growth was inhibited when treated with high concentrations of chromium (more than 1000 μM). Up to 150.99 and 979.03 mg·kg−1 DW of chromium accumulated in the aerial part and root, respectively, under a treatment of 2000 μM Cr. The bioaccumulation factor (BCF) of P. sinese varied from 10.87 to 17.56, and reached a maximum value at the concentration of 500 μM. The results indicated that P. sinese showed strong tolerance and high accumulation capability under Cr stress. Therefore, the chromium removal potential of P. sinese has a great application prospect in phytoremediation.

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