Nickel Smelter Research Articles

Dynamic variation of histone H3 trimethyl Lys4 (H3K4me3) and heterochromatin protein 1 (HP1) with employment length in nickel smelting workers

Objective: To investigate the dynamic variation in H3K4me3 and HP1 with employment length in nickel smelting workers.Methods: Blood samples were collected from 140 nickel smelting workers and 140 age-matched office workers to test for H3K4me3, and HP1 levels.Results: H3K4me3 was statistically significantly different (p < 0.05) between the two groups and positively correlated with employment length (rs = 0.267). HP1 was not correlated with employment length (p = 0.066) but was significantly different between the two groups.Conclusions: Chronic exposure to nickel can induce oxidative damage, and increase H3K4me3 expression and inhibit HP1 expression.

Nickel smelting dust exposures to NIH/3T3 cellular mitochondrial damage and L-ascorbic acid interference effect

To study the protection of L-ascorbic acid on mouse embryonic fibroblasts (NIH/3T3) from carcinogenic effects caused by nickel smelting smoke subjects. The NIH/3T3 cells were divided into experimental and L-ascorbic acid in the intervention group. Plus exposure group concentration of nickel refining dusts were formulate 0.00, 25.00, 50.00, 100.00 μg/ml suspension, the intervention group on the basis of the added exposure group containing L-ascorbic acid (100 mmol/L) , contacted. Then, the cell viability was detected by MTT assay, we used Calcein-AM fluorescence probe to detect cell mitochondrial permeability transition pore (MPTP) changes, JC-1 staining to observe and detect the cell mitochondrial membrane potential (MMP) change, colorimetric quantitative to study the activity of mitochondrial respiratory chain complex Ⅰ,Ⅱ,Ⅲ,Ⅳ. Upon 24 h incubation, both cell relative inhibition rate, openness of MPTP were increasing enhanced by different concentrations, on the other hand, MMP and the activity of mitochondrial respiratory chain complexⅠ, Ⅱ, Ⅳ were obviously decreased, the differences were statistically significant (P<0.05) .After L-ascorbic acid intervention treatment, the results of the intervention group were lower than that of the exposure group, and the difference was statistically significant (P<0.05) , indicating the protection of L-ascorbic acid on cell mitochondrial from the nickel exposure damage. The damage effects of nickel on NIH/3T3 cell mitochondrial was significantly enhanced with the increasing concentration, and L-ascorbic acid has certain protection on cellular mitochondrial.

Effects of water acidification on element concentrations in natural waters of the Kola North

This study discusses the problem of evolution of water chemistry under the influence of acid loadings from copper–nickel smelters of the Kola mining and smelting company (“KGMK”). The natural waters of the Kola Peninsula are characterized by low contents of biogenic substances and mineral salts owing to low water temperatures and low mass transfer rates at high latitudes. Acid precipitation causes water acidification in regions made up by granite gneisses and sandy rocks. Unlike naturally acidic waters with high humic acid contents, these lakes have high-transparency waters. The results show that Cd, Bi, Se, and Re become involved in the transport fluxes irrespective of a natural or anthropogenic source of acidification. Acidified lakes have higher Zn, Pb, As, Bi, and Sb contents compared to neutral lakes. The high coefficient of aqueous migration of Se, Re, Bi, Sb, Cd, and Sn is indicative of the anthropogenically-induced dispersal of these elements.

Dynamics of snowmelt water composition in conifer forests exposed to airborne industrial pollution

An analysis is made of the spatial variability of snowmelt water composition (within and between biogeocenoses), with regard to its long-term dynamics, in pine and spruce forests exposed to airborne industrial pollution from the Europe’s largest Severonikel Copper–Nickel Smelter Complex. Snowmelt waters from under the tree canopy, compared to those from intercrown areas, contain higher concentrations of chemical elements due to their washing and leaching from tree crowns. This is especially true of spruce forests, since the crowns of spruce trees have a high sorption capacity. Distinct trends in the long-term dynamics of snowmelt water composition, related to reduction of industrial emissions, are observed in background forest areas and defoliating forests but not in the vicinity of pollution sources. It is shown that the main factors determining these dynamics in forests of the Kola Peninsula are edificator tree species, airborne industrial pollution, and, possibly, an increase in the number of days with above-zero temperatures in the period of snow accumulation, which facilitates washing and leaching of chemical compounds from tree crowns.

Sulphur Dioxide Adsorption on Nickel Smelting Industry in East Luwu Using a Solution of Hydrogen Peroxide

Research on SO₂ gas adsorption from emissions of nickel ore industries plant use coal in the smelting process and the production by using H₂O₂ as an adsorbent solution. The adsorbent used to reduce the level of SO₂ in the air pollution. This study includes the adsorption of SO₂ gas of 6 factory chimneys at the nickel ore industry (2 dryers, 2 kilns, and 2 furnaces). The results showed that the percentage ratio of the average absorbance between H₂O₂ and calcium carbonate in reducing greenhouse gas emissions of SO₂ into the air that is 95.00%: 93.34%. As for the rest of SO₂ gas unadsorbed fixed meet the quality standards specified (750 mg/m³). Batch adsorption was conducted with respect to concentration of adsorbent, the adsorption temperature, and contact time. It was shown that the optimum concentration of adsorbent was 5%, the adsorption temperature was 20°C, and contact time was 1800 second.

Nickel exposure to A549 cell damage and L-ascorbic acid interference effect

Studying different concentrations of nickel smelting smoke subjects of human lung adenocarcinoma cells (A549) carcinogenic effects, discusses the influence of L-ascorbic acid protection. The A549 cells were divided into experimental and L-ascorbic acid in the intervention group. Plus exposure group concentration of nickel refining dusts were formulated 0.00, 6.25, 12.50, 25.00, 50.00, 100.00 µg/ml suspension, the intervention group on the basis of the added exposure group containing L-ascorbic acid (100 mmol/L), contact 24 h. Detection of cell viability by MTT assay. When the test substance concentration select 0.00, 25.00, 50.00, 100.00 µg/ml experiment for internal Flou-3 fluorescent probe to detect cell Ca²⁺ concentration, within DCFH-DA detect intracellular reactive oxygen (ROS) content, real-time quantitative PCR (real time, in the RT-PCR) was used to detect cell HIF-1α gene expression. With the increase of concentration, subjects increased cell growth inhibition rate, intracellular Ca²⁺ concentration increases, ROS content increased, HIF-1α gene expression increased, differences were statistically significant (P < 0.05). After L-ascorbic acid intervention treatment, the results of the intervention group were lower than that of the experimental group, and the difference was statistically significant (P < 0.05), so L-ascorbic acid can effectively protect the nickel exposure damage to cells. With subjects following exposure to nickel concentration increased, its effect on A549 cell damage increases, L-ascorbic acid cell damage caused by nickel has certain protective effect.

Oxidation Potentials in Matte Smelting of Copper and Nickel

The oxidation potential, given as the base-ten logarithm of the oxygen partial pressure in bars and the temperature [log pO2/T, °C], defines the state of oxidation of pyrometallurgical extraction and refining processes. This property varies from copper making, [−6/1150]; to lead/zinc smelting, [−10/1200]; to iron smelting, [−13/1600]. The current article extends the analysis to the smelting of copper and nickel/copper sulfide concentrates to produce mattes of the type Cu(Ni)FeS(O) and iron silicate slags, FeOxSiO2—with oxidation potentials of [−7.5/1250].

Oxidative damage of NIH/3T3 cells induced by nickel smelting fumes

To investigate the cytotoxicity and oxidative damage on NIH/3T3 cells induced by nickel smelting fume. NIH/3T3 cells were treated with nickel smelting fume collected from a nickel smelting factory in China with doses of 0, 6.25, 12.50, 25.00, 50.00, and 100.00 µg/ml for 6 h. Dose-dependent cytotoxicity in cells were assessed by Cell Counting Kit-8 (CCK-8), natural red uptake assay, and lactate dehydrogenase (LDH) leakage assay, and the level of oxidative damage was assessed based on the activity of catalase (CAT), percentage inhibition of superoxide dismutase (SOD), and content of malonaldehyde (MDA). The relative survival of NIH/3T3 cells decreased with the increase in the dose of nickel smelting fume. In the CCK-8 assay, the group with 100 µg/ml nickel smelting fume showed a cell growth inhibition rate of 86%, with a significant difference compared with the control group (P < 0.05). LDH activity increased with increasing dose of nickel smelting fume: the groups of 12.50, 25, 50, and 100 µg/ml nickel smelting fume all showed increased LDH activities as compared with the control group (P < 0.05). The activities of CAT were significantly reduced in groups of 25, 50, and 100 µg/ml nickel smelting fume as compared with that of the control group (P < 0.05). As the dose of nickel smelting fume increased, the percentage inhibition of SOD and the content of MDA increased, with significant differences compared with the control group (P < 0.05). Oxidative damage may be induced in NIH/3T3 cells after 6 h of exposure to nickel smelting fume, which leads to cell death.

Need for database extension for reliable identification of bacteria from extreme environments using MALDI TOF mass spectrometry

AbstractThe ability of MALDI TOF MS (matrix-assisted laser desorption ionisation time-of-flight mass spectrometry) to identify cultivable microflora from two waste disposal sites from non-ferrous metal industry was analysed. Despite the harsh conditions (extreme pH values and heavy metal content in red mud disposal site from aluminium production or high heavy metal content in nickel sludge), relatively high numbers of bacteria were recovered. In both environments, the bacterial community was dominated by Gram-positive bacteria, especially by actinobacteria. High-quality MALDI TOF mass spectra were obtained but most of the bacteria isolates could be not identified using MALDI Biotyper software. The overall identification rate was lower than 20 %; in two of the environments tested identification rates were lower than 10 %. As a dominant bacterial species, Microbacterium spp. in drainage water from an aluminium red mud disposal site near Žiar nad Hronom, Bacillus spp. in red mud samples from the same site, and Arthrobacter spp. from nickel smelter sludge near Sereï were identified by a combination of the Biolog system and 16S rRNA sequence analysis. As the primary focus of the MALDI TOF MS-based methodology is directed towards medically important bacteria, reference database spectra expansion and refinement are needed to improve the ability of MALDI TOF MS to identify environmental bacteria, especially those from extreme environments.

Oxidation Potentials in Iron and Steel Making

The state of oxidation of a pyrometallurgical process given by the partial pressure of oxygen and the temperature (the oxidation potential) is one of the important properties monitored and controlled in the smelting and refining of iron and the nonferrous metals. Solid electrolyte sensors based on ZrO2 and a reference electrode such as Cr/Cr2O3 to measure the oxygen pressure found early application in the steel industry, followed soon after in copper, nickel, lead, and zinc smelting. Similar devices are installed in automobile postcombustion/exhaust trains as part of emission control systems. The current discussion reviews this technology as applied in the primary steps of iron and steel making and refining.

On-Line Monitoring System for Process Parameters of Nickel Smelting

Based on the nickel smelting process in the smeltery of a corporation, a real time monitoring system of process parameters acquisition is developed, which makes full use of the choice of equipment, the telecommunication technique of PLC, and the data processing technique to carry on display of the technological parameters, data communication, alarm of demarcation line and tendency analysis etc. The system provides an efficient monitoring and analyzing in the production process for management and operation personnel and enhances the management level of modernization.

Optimal Converter Aisle Scheduling in a Nickel Smelting Plant

The manual scheduling of operations in a Converter Aisle for Nickel Smelting is both a time-consuming and tedious task. The challenge of manually scheduling this process involves several tasks on multiple units (such as tapping of matte from furnaces, charging of converters, blowing, and skimming slag from converters). Furthermore, these tasks need to be carried out subject to a number of operational constraints that include upper and lower matte level limits in the furnaces, and the number and timing of the blowing operations required for a converter batch. This already complex set of tasks is further complicated by emission limits, which places additional constraints on the Converter Aisle operation. However, when process disruptions invalidate the nominal schedule, it falls on operators to rely on operating protocols and experience to navigate the process operations and obey operating constraints as best as possible. These considerations motivate the development and use of an optimal scheduling decision support system that is capable of timely process scheduling, while respecting operational constraints, to achieve a given objective. The work presented formulates the operation scheduling as a mathematical optimization problem, where the relationships between the material flows, compositions, operating procedures, event timing and various constraints are captured, and the optimization objectives are quantified. The problem is expressed in a standard mathematical form that is amenable to solution using commercial optimization software. The project explores optimization opportunities in order to identify optimal scheduling configurations that are not realizable based on human intuition due to the complexity inherent in the process.

Influence of a nickel smelter plant on the mineralogical composition of attic dust in the Tikveš Valley, Republic of Macedonia

Mineral phases and their content were determined in attic dust samples collected from 27 houses in the Tikveš Valley, Republic of Macedonia. By using quantitative X-ray diffraction, the principal mineral phases were determined to be the serpentinite group (chrysotile, lizardite) and amphibole group of minerals (ribecite, tremolite, actinolite) present in the attic dust samples from this region which are not common constituents of urban dust. Strong correlations existed between these mineral phases in the dust and those in ores processed at a ferronickel smelter plant situated in this region. Spatial distributions of specific mineral phases were made and were consistent with wind directions and predicted deposition (60-70 %) of dust emitted from the metallurgical plant.

Flux calculation using CARIBIC DOAS aircraft measurements: SO2 emission of Norilsk

Based on a case‐study of the nickel smelter in Norilsk (Siberia), the retrieval of trace gas fluxes using airborne remote sensing is discussed. A DOAS system onboard an Airbus 340 detected large amounts of SO2 and NO2 near Norilsk during a regular passenger flight within the CARIBIC project. The remote sensing data were combined with ECMWF wind data to estimate the SO2 output of the Norilsk industrial complex to be around 1 Mt per year, which is in agreement with independent estimates. This value is compared to results using data from satellite remote sensing (GOME, OMI). The validity of the assumptions underlying our estimate is discussed, including the adaptation of this method to other gases and sources like the NO2 emissions of large industries or cities.

Scuttle flies (Diptera: Phoridae) caught at dead mice in S. W. Finland

Scuttle flies trapped at baits of dead mice are reported from a region of S. W. Finland subjected to pollution from the smelt-ing of copper and nickel. Most belonged to the huge genus Megaselia, but 96% were females, the majority of which cannot be named until linked to their males. These are given code numbers and distinguished by means of a key.

Influence of Fe&lt;sub&gt;2&lt;/sub&gt;O&lt;sub&gt;3&lt;/sub&gt; on Molten Slag Properties in Slag Splashing on Nickel Smelting Converter

To predict the effect of Fe2O3 on slag splashing properties in the nickel smelting converter, Factsage software was used to calculate the proportion of the liquid phase and the viscosity for MgO-FeO-Fe2O3-SiO2 melts, the melting temperature was measured using slag column deformation, and the microstructure was also observed. The results show that, when the content of Fe2O3 is increased from 13.79% to 24.14%, the liquid phase at 1250°C maintains a high proportion of 82.68% and the melting temperature is below 1200°C; The magnetite and hortonolite with high melting points are considerably increased, and the viscosity rises accordingly. The melting and viscous properties for the slag with high content of Fe2O3 were improved by adding MgO. Desired slag splashed layer was formed with the saturated Fe2O3 and MgO slag.

Evaluating the respiratory bioaccessibility of nickel in soil through the use of a simulated lung fluid

Simulated lung fluids are solutions designed to mimic the composition of human interstitial lung fluid as closely as possible. Analysis of mineral dusts using such solutions has been used to evaluate the respiratory bioaccessibility of various elements for which solubility in the lungs is a primary determinant of reactivity. The objective of this study was to employ simulated lung fluid analysis to investigate the respiratory bioaccessibility of nickel in soils. Current occupational guidelines in Australia regulate nickel compounds in terms of water solubility, though this may not be an accurate estimation of the total nickel that will dissociate in the lungs. Surface soils were collected from the city of Kalgoorlie in Western Australia, the site of an operational nickel smelter and metal mining activities. The fraction of the samples less than 10 μm was extracted from the soil, and it was this sub-10-μm fraction that was found to hold most of the total nickel present in the soil. The fine fraction was analyzed using a simulated lung fluid (modified Gamble's solution) to isolate the nickel phases soluble in the lungs. In addition, a sequential extraction was employed to compare the bioaccessible fraction to those dissolved from different binding forms in the soil. In all samples, the simulated lung fluid extracted more nickel than the two weakest leaches of the sequential extraction combined, providing a more representative nickel bioaccessibility value than the current water leach method.

Patterns of insect communities along a stress gradient following decommissioning of a Cu–Ni smelter

The diversity, estimated richness and abundance of terrestrial insect communities were examined along a stress gradient of past pollution in the region of Sudbury, Ontario, Canada. This gradient represents the natural recovery and lingering effects of a decommissioned copper–nickel smelting complex. Ant genera and sixteen higher taxonomic groups (family and order) had the highest abundance at the sites with intermediate stress. Eight families increased in abundance with distance from the decommissioned source of pollution and eleven families decreased reflecting a complex response of diversity to pollution. Carabid beetles show an increase in diversity further from the smelter; however, examination of the species composition reveals a distinct carabid community closest to the smelter, emphasizing the unique habitat created by severe pollution. Although almost forty years since decomissioning of the smelter complex, the terrestrial insect community in the vicinity remains significantly impacted suggesting slow recovery.

Breast Cancer Risk Associated With Residential Proximity to Industrial Plants in Canada

The relationship between breast cancer risk and residential proximity to paper mills, pulp mills, petroleum refineries, steel mills, thermal power plants, alum smelters, nickel smelters, lead smelters, copper smelters, and zinc smelters was assessed. We conducted a population-based case-control study of 2343 cases with breast cancer and 2467 controls using residential proximity at some time between 1960 and 5 years before the completion of questionnaire in Canada. Adjusted odds ratios were statistically significantly increased for residing near steel mills (0.8 to 3.2 km) and thermal power plants (<0.8 km) in premenopausal women, petroleum refinery (0.8 to 3.2 km) and pulp mills (0.8 to 3.2 km) in postmenopausal women, and for 10 or more years of residing near thermal power plants of 0.8 km. Our preliminary results suggested possible weak associations between breast cancer and proximity to steel mills, pulp mills, petroleum refineries, and thermal power plants.

Nickeliferous pyrrhotite – “Waste or resource?”

Currently nickel producers are keeping a close eye on both the economic and production developments taking place at the Talvivaara open pit mines and their bio-heap-leach operations located in Finland. The concept of open pit mining combined with heap leaching is a popular concept in the copper industry and practiced on oxidised copper ore bodies with less than 1% Cu. In general, this process consumes large quantities of sulphuric acid when based on oxide mineralogy. Talvivaara is processing very low-grade, but complex Ni, Zn, Cu sulphide ore (0.27% Ni, 0.57% Zn and 0.14% Cu). Its full contained metal value at 70% base metal recovery is estimated at 40–50 USD/MT ore using long-term metal prices (all elements). Low-grade complex disseminated nickel sulphide ore bodies are fairly abundant worldwide, but in general not yet economically treatable through the conventional mine-mill-smelter route. In the Sudbury basin of Ontario there is a vast resource of ∼0.8% Ni-bearing pyrrhotite tailings, which has been disposed of separately in shallow lakes since the early 1990s in compliance with known environmental and sustainable development standards. The estimated full contained metal value at 70% nickel recovery from pyrrhotite is estimated at 90–100 USD/MT using the same long-term metal prices as for Talvivaara. Supply of sulphuric acid is abundant from nickel smelter operations in the basin. There are, in addition, many other low-grade ore bodies where nickel-bearing pyrrhotite, with or without pentlandite exsolution flames, is readily available. This commercial context raises the question whether Ni-bearing pyrrhotite can be considered a sustainable resource. In this paper some historical context behind pyrrhotite processing in the Sudbury area is provided. Flow sheet design considerations based on both technical and economic factors are reviewed with the objective of providing the nickel industry with tools for informed decision-making on the possibilities for exploitation of this low-grade nickel sulphide raw material.