Ore Quality Research Articles

Current methods and possibilities to determine the variability of Cu content in the copper ore on a conveyor belt in one of KGHM Polska Miedz S.A. mines

In this paper the methodology of ore sampling on a belt conveyor in one of KGHM Polska Miedz S.A. mines was presented together with the results of analysis of the variation of ore tonnage and quality. The ore was transferred from one mine to another one through the analysed transfer conveyor on the route from the mine Division of Mining to copper plants. The transported ore was sampled in person from Division of Concentrators on a regular basis for metal accounting purposes between both mines. The ore quality control became a significant problem since it is impossible to predict with satisfactory advance both Cu content in the feed as well as its lithology composition which is required to improve and optimise the enrichment efficiency.

Control of clay minerals effect in flotation. A review

The increased exposure to low grade ores highlights the importance of understanding phyllosilicate gangue mineralogy which consists of common gangue minerals. To improve the flotation performance and ore quality the negative effect of the clay minerals on flotation should be identified. The presence of clay minerals leads to problems, such as changing the froth stability, which are related to swelling behaviour, increase in pulp viscosity, overconsumption of reagents, slime coating and mechanical entrainment. The clay content in the ore is changing from time to time and it is necessary to provide quick solutions to the issues caused by the new ore composition. The objective of this paper is to give an overview how to control the colloidal properties of clay minerals on flotation.

Precision Surface Mining, the Next Steps

Precision surface mining is gaining traction in the phosphate, iron ore, copper, iodine, limestone, bauxite, coal and gypsum markets. Precision surface mining allows following an ore body in three dimensions to increase ore quality over that possible from drill and blast techniques by keeping the ore separate from the waste. In addition to eliminating the need for a primary crusher, precision surface mining allows for production of a uniform material with a tight particle size distribution. Top-down cutting allows variation in product size, with fewer fines being generated than that obtained in the same material using drill and blast techniques. In this study, we present case studies in Chile (iodine) and South Africa (coal) to illustrate these results. Vermeer is committed to developing the capabilities of our surface mining machines to make them more efficient and environmentally friendly. The second section of the paper is focused on a new dust containment capability not involved with using water. The remainder of the paper describes step-by-step developments of the Vermeer “road to autonomy.” While true autonomous operations are sometime in the future, there are several necessary steps along the way which must be operational. These include a remote control capability to allow mining next to walls, an operating system (SmartTEC) which teaches the operator how to more efficiently run the machine – along with presenting operational data for management purposes. In addition this section includes a description of automatic steering using GPS techniques – both in a straight line and turning.

Conectando el pasado con el presente: la antropología histórica de la producción de metal a pequeña escala en Porco, Bolivia

Andeanist archaeologists have the opportunity to participate in the development of an historical anthropology (Lightfoot 1995) in which archaeological research on the post-conquest era connects the prehispanic past with the present. This essay seeks to contribute to this type of archeology by examining data produced by the Archaeological Project Porco - Potosi in investigating Porco, a mining center in Bolivia, 35 km southwest of Potosi, whose main objective is to investigate the organization of silver production under the different political and economic systems that have characterized the region. Mining has been important in Porco since the Inka era, when it provided silver to adorn the Koricancha in Cusco. It continues today in the form of zinc mining carried out by an international company, Sinchi Wayra, and several local cooperatives. The archaeological record in Porco can thus inform us of continuities and changes in mining activities over the past 500 years. In addition to the Spanish conquest, another important historical rupture in Porco’s mining industry occurred in the late nineteenth century, when tin and zinc mining funded by foreign enterprises replaced the former system of silver extraction by forced labor. Despite fundamental differences between the two forms of production, archaeological survey and excavations carried out by the project indicate that both systems were characterized by k’aqcheo – the “theft” of high quality ore - associated with small-scale silver production using technology such as the native huayrachina. In contrast to mining in the United States and other wealthy countries, the ongoing process of development in Bolivia in the mining sector is not a unilinear march towards “modern” industry, but a series of complicated interactions between companies and miners involving both competition and interdependence.

Оценка качества и литологических особенностей кимберлитовых руд по микроалмазам

Оценка качества и литологических особенностей кимберлитовых руд по микроалмазам

Biotechnological magnesite enrichment using a carbonate dissolving microorganism, Lactococcus sp.

The usage of magnesite strictly depends on its impurities. CaCO3 is the major impurity in magnesite ores. The amount of CaCO3 should be less than 1% for the quality and economical use of magnesite ores. Some magnesite ores in Turkey cannot be used due to high amount of CaCO3 (≥3%). This study aims to investigate an alternative biotechnological method for decalcification of magnesite ores by using a microorganism (Lactococcus spp.). The amount of CaCO3 was reduced from 2.94% to 0.57%. This reduction improved the quality of magnesite ore by approximately 80.61%. The results showed that Lactococcus spp. can be used safely in industrial decalcification of magnesite ore as the microorganism has no pathogenic properties.

Application of Boron-bearing Iron Concentrate to Optimizing Sintering Quality of High Chromium Vanadium-Titanium Magnetite Ore

Application of Boron-bearing Iron Concentrate to Optimizing Sintering Quality of High Chromium Vanadium-Titanium Magnetite Ore

X-ray fluorescence determination of the manganese valence state and speciation in manganese ores

This work concerns determination of the manganese valence state and speciation by wavelength-dispersive X-ray fluorescence analysis. The authors investigated the effect of the manganese valence state and speciation on the intensity of some К-series lines of the X-ray emission spectrum for the samples of manganese compounds. The intensities of MnKβ5 line and MnKβ′ satellite are least influenced by speciation, and they may be used for evaluating the manganese valence state for the samples containing low iron. The intensities of MnKβ″ and MnKβx satellites may be employed for assessing the manganese speciation. The results of X-ray fluorescence determination of the manganese valence state and speciation in the manganese ores of the South Ural deposits agree with the X-ray diffraction data. The X-ray fluorescence method is definitely advantageous, because it does not require a complicated process of sample preparation and allows to receive fast information on the manganese valence state and speciation with the purpose to assess the quality of manganese ores. Copyright © 2015 John Wiley & Sons, Ltd.

PROSPECTS FOR THE USE OF ELECTRO-PHYSICAL METHODS OF TREATMENT IN THE ENRICHMENT OF IRON ORES

Proposed way to improve the quality of iron ore concentrate in reverse flotation with cationic reagent with the combined use of electric pulse and electrochemical treatments.

Liquid Absorbability of Iron Ores and Large Limonite Particle Divided Adding Technology in the Sintering Process

Quality of sinter increasingly influences the running‐condition of blast furnance in Asian countries where sinter is the main raw material of BF. While with the gradually decline of iron ore quality, characteristics of iron ore play more and more improtant role on the quality of sinter, so to clarify the influence of high‐temperature characteristics of large iron ore particles on the strength of sinter, liquid absorbability of iron ore particles was proposed and tested, as well as bonding strength tests. Then Large Limonite Particle‐Divided Adding Sinter (LLP‐DAS) was proposed and tested aiming to weaken the negative influence of large limonite particles on the strength of sinter. The results show that great differences of liquid absorbability of iron ores are presented. Iron ores with high porosity and LOI, small grain size, high T.Fe content, and low Al2O3 content have high absorbability. Bonding strength of sinter body decreases with the increase of absorbability of nuclei iron ore because the decrease of effective bonding phase caused by the liquid absorption reaction. In addition, LLP‐DAS presents good performances under the condition of high ratio of limonite in the sintering process, Sinter speed increased 0.9 mm min−1, yield increased 0.5%, and productivity increased 1.3 t m−2 d−1.

Mineralogy of Iron Ores of Different Alumina Levels from Singhbhum Belt and Their Implication on Sintering Process

To increase the life of the mines, ores of lower quality are blended with the higher quality ores. In general, the blending of ores at mines site is controlled by the chemical composition of the ores by controlling the Al2O3 and SiO2 levels on the lowest side possible. However, if there is a change in mineralogy, like an increase in hydrous phase the composition may still be the same, but this difference may affect the sinterability and sinter quality. The mineralogical investigation of iron ores and their chemistry are required to avoid the increase in deleterious elements during sintering. By the know-how of the behavior of individual iron ores in terms of their sinterability, in advance, the quality of the iron ores blend can be optimized to produce quality sinter and productivity. Characterisation studies conducted on iron ores of Singhbhum Orissa belt revealed that hematite, goethite, clay, gibbsite and quartz occur in all the iron ore samples but in variable proportions. Traces of alumina, present as solid solution in the iron oxide minerals, has also contributed Al2O3 to the ores.

ANALYSIS AND USE OF Mn ORE FINES

This article deals with the analysis and use of Mn ore fines in the production of ferroalloys. The paper focuses on the evaluation of Mn ores in terms of their chemical and phase composition. Mn ore fines are formed in the process of mining, transport and processing of Mn ores in factories. These small particles cannot be directly put into the furnace; they should be edit before they are used. The most appropriate treatment method of Mn ore fines is sintering. Laboratory experiments were done with Mn ore from Turkey, Bosnia and Herzegovina and Bulgaria. Analyses of the Mn ores were performed in order to determine their various properties, according to which conditions were adapted for laboratory experiments to produce the best quality Mn sinter. Chemical and phase composition and thermal analysis have been performed on the ores. The phase analysis showed that the ore from Turkey and Bulgaria are in the carbonate form and the ore from Bosnia and Herzegovina is in the oxide form. DTG analysis showed that, by the thermally heating the biggest weight loss happened in the Mn ore from Bulgaria. For the best quality ore can be considered the Mn ore from Turkey because it containsthe highest % of Mn, lowest content of SiO2 and the ore has the lowest % of P. The sizing of Mn ore fines was carried out in laboratory conditions on a laboratory sintering pan. Produced Mn sinters were subjected to analysis of their chemical and phase composition. Produced Mn sinters have higher content of Mntot compared to Mn ores. As a result of Mn ore sintering the form of majority compounds changed - silicates, carbonates and hydrates of manganese in the starting Mn ores were in the produced Mn sinters analysed majority compounds based on the higher oxides of Mn and Fe, which is in the process for production of Mn ferroalloys positive.

Interação Consumidor-Funcionário no Varejo de Confecção sob a Perspectiva da Classe Média

This study aims at analyzing the influence of consu mer–employee interaction quality in store recommendation and purchase intentions for a clothi ng store by middle class consumers. The research started with a qualitative exploratory pha se conducted through interviews and a focus group. I was followed by a quantitative step implem ented through a conclusive causal research through an experimental study. Results sho w that there is a high correlation between the quality of consumer-employee interaction and st ore and recommendation and purchase intentions. The greater the positive interaction be tween the middle class consumer and employees of the retail clothing industry, the grea ter the purchase intention and recommendation of the consumer, while the reverse is also true

PLSR as a new XRD method for downstream processing of ores: – case study: Fe2+ determination in iron ore sinter

The use of high-speed detectors made X-ray diffraction (XRD) become an important tool for process control in mining and metal industries. Decreasing ore qualities and increasing prices for raw materials require a better control of processed ore and a more efficient use of energy. Traditionally quality control of iron ore sinter has relied on time-consuming wet chemistry. The mineralogical composition that defines the physical properties such as hardness or reducibility is not monitored. XRD analysis in combination with Rietveld quantification and statistical data evaluation using partial least-squares regression (PLSR) has been successfully established to determine the mineralogical composition and the Fe2+ content of iron ore sinter within an analysis time of less than 10 min per sample. A total of 35 iron ore sinter samples were measured and evaluated using PLSR and the Rietveld method. The results were compared with wet chemistry data. PLSR results show accuracy for the Fe2+ content of ±0.14%. No pure phases, crystal structures, or complex modeling of peak shapes are required. The Rietveld method was used to quantify the total phase composition of the samples. The Fe2+ content could be calculated from all phases present. Both methods take the full XRD pattern into account and can be simultaneously applied on the same measurement. PLSR was found to be the more robust method if only Fe2+ results are required. The Rietveld method helps predict other parameters such as the compressional strength of the sinter by monitoring all existing phases (e.g., larnite, C2S, or silico-ferrite of calcium and aluminum phases).

Study on Parameters of Slurry Pipeline Transportation Technology in Grade

In generally, there are multiple factories. According to mining areas, it supplies different quality iron ore concentrate. And according to the unique requirements of owners, different grades concentrate cannot be confused. Therefore, the grade of slurry pipeline transportation is needed to be used. When in the study of grade transmission, we must focus on Hydraulic characteristics of solid-liquid two-phase for different quality of iron ore concentrate. Slurry concentration and Critical velocity of flow is especially important. Research shows that the deposition rate of laminar or turbulent transition velocity is higher than the occasion when the slurry has concentration, so the minimum operating speed is controlled by sedimentation; the concentration lower limit is 62%. If the concentration is over 68%, the yield stress of slurry will increase, and the pipeline pressure will drop, which is very sensitive to slight changes in concentration. Therefore, the solid weight concentration range is 62% to 68%,as the selection range of design.

Phosphorus: The Noose of Sustainability and Renewability in Steelmaking

With rising ore prices and the continued demand for higher quality steels, much work has been carried out into refining and control prospects of steel chemistry. As several technologies around the world are exploring the control of phosphorus with high priority, an overview of current knowledge, ongoing research, and specific interest areas is presented. The reliance of the basic oxygen furnace steelmaking on iron ore quality is considered with regard to impurity levels, as well as the phosphorus content of direct reduced iron introduction to the electric arc furnace process. This article reviews methods to control phosphorus in steelmaking and proposes a practical approach based on laboratory-scale equilibrium experiments. The article ends by exploring energy savings in steelmaking as well as speculating on further avenues of steel production profitability.

Hydrothermal synthesis of high purity zeolite A from natural kaolin without calcination

Zeolite A is a commercially and environmentally important microporous material, which is commonly synthesized from calcined kaolin. One major drawback inherent to this approach is that the properties (i.e., purity, particle size, morphology, and cation-exchange capacity) of the final product depend largely on the quality of the raw kaolin ores. Herein we report on a new hydrothermal route for the synthesis of high purity zeolite A with controllable particle size and morphology, from natural kaolin without conventional high temperature calcination. This route starts with hydrothermal reaction of natural kaolin with NaOH to form hydrous sodium aluminosilicates (i.e. hydroxycancrinite and nepheline hydrate), which are then dissolved in dilute HCl. The resulting acid solution, after filtration to remove unreacted impurity minerals such as quartz and muscovite, is then adjusted to pH=7 to form an amorphous Si and Al gel, which is used for the hydrothermal synthesis of zeolite A. A comparative study of zeolite A samples synthesized from this new route and those from the conventional calcination method reveals that the former have more controllable size and morphology than the latter, giving rise to higher brightness and enhanced cation-exchange capacity. Another major advantage of this new method is that the common impurity minerals such as quartz, muscovite and feldspars in natural kaolin can be removed, giving rise to high purity zeolite A and possibly expanding this technique to the use of low-grade kaolin.

Mineralogical and geochemical evolution of the Fusui bauxite deposit in Guangxi, South China: From the original Permian orebody to a Quarternary Salento-type deposit

Two types of bauxite deposits have been discovered in the Fusui area, Guangxi Province, South China. The original Permian bauxite occurs on the unconformity between the Middle Permian Maokou Formation and the Upper Permian Heshan Formation. The Salento-type (or karstic accumulational) bauxite is composed of the Quaternary incompact sediments that transformed from the original Permian bauxite. Samples were collected from two drilling cores and two profiles in study area, and field observations and mineralogical and geochemical analyses are integrated to reconstruct the metallogenic process from the original Permian bauxite to the Quaternary Salento-type bauxite. In the Permian lateritization and bauxitization, alkali metals and alkali earth metals are preferentially dissolved and removed from the parent rocks due to the intense chemical weathering; other major elements from the original profile are also depleted, as shown by the mass-change calculation result. Elements with a low mobility (e.g., Ti, Zr, Cr, Nb and V) are positively correlated with Al. When the bauxite deposit is affected by the modern groundwater system in the near-surface environment, the elements in the deposit display varied mobility due to the leaching intensity and the drainage conditions. After the bauxite ore horizons are exposed in the surface environment, impurities (primarily Fe and Si) are removed from the profiles, and Al is enriched; the clay minerals (kaolinite and chlorite) in the ores convert into aluminum minerals (boehmite and diaspore). When the exposed original bauxite orebodies break down and accumulate as bauxite gravel in the modern karstic depressions, the Salento-type bauxite deposits appear, and the ore quality is further improved. The intensity of the leaching process and the drainage conditions are the most important factors that control the ore quality during the ore-forming process that converts the original bauxite into the Salento-type bauxite.

Looking beyond chemistry – XRD for exploration and processing of ores

Decreasing ore qualities and increasing prices for raw materials require a better control of processed ore and a more efficient use of energy. Traditionally quality control in mining industries has relied on time consuming wet chemistry or the analysis of the elemental composition. The mineralogy that defines the physical properties is often monitored infrequently, if at all. The use of high speed detectors has turned X-ray diffraction (XRD) into an important tool for fast and accurate process control. XRD data and their interpretation do make the difference in the identification of minerals, in describing their distribution in ore bodies and in their beneficiation during processing. The use of modern techniques such Partial Least Square Regression (PLSR), Principal Component Analysis (PCA) or full pattern Rietveld quantification will be discussed during the presentation as well as the importance of adequate sampling and the correlation with sample chemistry. The practical use will be illustrated on case studies.

CO2 emission and mitigation potential estimations of China's primary aluminum industry

This paper reviews the features of bauxite resources and fuels utilized in China's primary aluminum industry, which was not adequately discussed in previous studies with the existing general CO2 assessment approach. Targeted at this matter, this article develops a bottom-up calculation and scenario analysis model to estimate CO2 emissions and reduction potentials for China's primary aluminum industry. In this model, the complex structures of feedstock, technology and electric power are completely considered. CO2 emissions from alumina and aluminum production in the selected year are calculated using this model, and emissions associated with five distinct refining technologies and smelters in the six regional power grids are examined in detail. Results show that CO2 emissions of primary aluminum production in China could decrease at various extents through implementing alternative countermeasures for ore quality changes and policies adjustment in the future. It's expected that wide adoption of SBSP and IBP as well as further elimination of LSSP and SPCP have a reduction potential of 6%, which is almost equivalent to the cutting effect of SBP domination. For smelting stage, the maximum reduction potential of 20% is projected for 2020, as the current international best available value of power consumption is achieved.