Ore Production Research Articles

Geochronological constraints on the genesis of high-grade iron ore in the Gongchangling BIFs from the Anshan-Benxi area, North China Craton

The Gongchangling iron deposit located in the northeast of the North China Craton is hosted in late Neoarchean Algoma-type BIFs. It is famous for the major production of high-grade iron ore in the Gongchangling No.2 mining area in China. With regard to the genesis of high-grade iron ore, more and more evidences indicate that it was related with hydrothermal enrichment of BIFs. However, the hydrothermal nature was argued for meteoric, metamorphic or migmatitic fluid. In this study, the trace element compositions of garnet from the altered wall-rock of high-grade iron ore obtained by LA–ICP–MS show compositional zoning, indicating it is a metamorphic origin. These garnets yield a Sm–Nd isochron age of 1888 ± 77 Ma, interpreted as the time of metamorphism in this area. LA–ICP–MS U–Pb dating of zircon from the upper migmatite zone shows that the migmatitic granite was formed at 2478 ± 36 Ma. Since the REE patterns of garnet suggest that it was formed in the nearly neutral fluid rather than the acid meteoric fluid in the Paleoproterozoic. Hence, combined the ages of metamorphism and migmatization with high-grade iron ore of 1840 ± 7 or 1860 ± 7 Ma obtained by previous studies, it indicates that the genesis of the high-grade iron ore derived from the enrichment of BIFs by metamorphic hydrothermal fluid.

The issues of optimization parameters of quarry transport systems

The cost of technological transport in open-pit mining for medium-depth quarries reaches 50 % of the total cost of production of commercial ore, and for deep-exceed this figure. Therefore, optimization of quarry transport systems is an important element in improving the efficiency of mining. The most important element of optimization is through her character the use of optimization to all linked processes on the basis of objective criteria of efficiency, unity and objectivity of the source data, using multilevel data from sensors mounted on the mining and transport machines to total economic values for processing. A promising direction for the implementation of tools for optimizing the processes of open pit mining and in particular transport systems of quarries, as one of the most important subsystems, is the end-to-end digitalization of mining production. The article presents the results of research and methodological approach to the creation of methods of optimization of complex transport systems on the basis of complex computer modeling, both simulation and economic and mathematical. The concept of TSC optimization methods in the absence of expressed maxima or minima of the parameters reflecting the optimization parameters is proposed. The possibilities of optimization of transport systems due to controlled transients are shown, it is established that the rational organization of the transition process provides cost savings of up to 2 times or more. The concept of a dynamic model of the quarry transport system development, reflecting the transition processes in its formation, is presented.

Deep Neural Network for Predicting Ore Production by Truck-Haulage Systems in Open-Pit Mines

This paper proposes a deep neural network (DNN)-based method for predicting ore production by truck-haulage systems in open-pit mines. The proposed method utilizes two DNN models that are designed to predict ore production during the morning and afternoon haulage sessions, respectively. The configuration of the input nodes of the DNN models is based on truck-haulage conditions and corresponding operation times. To verify the efficacy of the proposed method, training data for the DNN models were generated by processing packet data collected over the two-month period December 2018 to January 2019. Subsequently, following training under different hidden-layer conditions, it was observed that the prediction accuracy of morning ore production was highest when the number of hidden layers and number of corresponding nodes were four and 50, respectively. The corresponding values of the determination coefficient and mean absolute percentage error (MAPE) were 0.99% and 4.78%, respectively. Further, the prediction accuracy of afternoon ore production was highest when the number of hidden layers was four and the corresponding number of nodes was 50. This yielded determination coefficient and MAPE values of 0.99% and 5.26%, respectively.

Narrowing the gap between local standards and global best practices in bauxite mining: A case study in Malaysia

In mining the concept of sustainable development often encounters a paradoxical meaning as numerous mines in the past have closed due to exhausted amounts of ores. Despite the paradox, sustainable development and mining can be made compatible, if mining activities are carried out responsibly and sustainably. This holds true especially in the developing world where illegal and unregulated mining is still being practiced. In Malaysia, annual production of bauxite ore increased drastically from 208,770 tonnes in 2013, to 962,799 tonnes in 2014. The increase stemmed primarily from Indonesia banning exports of bauxite in 2014 to boost its own aluminium smelting industry. This led China to suffer low bauxite supply to meet its national aluminium production demand. Subsequently, mining companies flocked to the hills around Kuantan, Malaysia which host large amounts of low-grade bauxite where the ore is procured and exported to China via seaway. The immediate spike in bauxite production came with environmental and health consequences for residents due to unregulated rampant mining. Consequently, the authorities imposed a temporary moratorium on bauxite mining from Jan 15, 2016 with exceptions for exports of stockpiled bauxite. As a result, production in 2016 dropped to 342,924 tonnes from a peak of 7,164,956 tonnes in 2015. After extending the moratorium nine times, the government announced recently that there would be no further extension and mining could resume in April 2019 with new standard operating procedures (SOP). This work analyses the gap between local standards and global best practices and discovers a disconnect between the two, largely centred around the area of environmental management and performance. The work also elucidates the weaknesses in the current SOP and strategies are proposed to resolve these shortcomings. Recommendations are made to bring Malaysian bauxite mining practices to international standards by stressing on improved sustainability indicators, policy provisions and data transparency.

PERENCANAAN TEKNIS OPERASI PRODUKSI BIJIH TIMAH DI BLOK 3 TAMBANG BESAR 2.1 MITRA PT TIMAH (PERSERO) TBK

The process of tin ore mining in TB 2.1 is conducted by channeling slurry (the mixture of ore and water) from the stock pile into the washing unit by using slurry pump. Now, TB 2.1 is planning block 3 for the operation of tin ore production proceess. Thus, a good technical planning in accordance with the characteristic of tin ore in TB 2.1 and evaluation of operating system design in Block 1 are necessary. The sample of tin ore concentrate is taken as many as 250 gr from the washing unit to detect P80 of particle size distribution (PSD) of sample. The data of sucker and pressure pipe’s lenghth, store tank’s height, quantity of primary and secondary jig and tin ore monthly production are required to furthermore plan the mining design, washing plant and equipment needs in the drying unit. Based on the research findings, It is obtained the grain size distribution of tin ore is 1.001 mm, so that the amount of lifting velocity is 3.27 m/s. Slurry pump discharge with a pipe’s diameter of 10 inches is 54 m3/hour, while total head of mining design is 30.23 m. Width of launder required is 6.5 m and equipped with two Grizzlies. Washing plant requires three units of primary Jig (2 × 3 cell) and a unit of secondary jig (2 × 3 cell). Adding rotary vibrating screen, shaking table and rod mill are necessary for process optimization in the drying unit.

Chemical waste management is still in a very poor state in much of Asia

China is one of the largest producers, consumers, and emitters of cadmium (Cd). This study applies the methods of material flow analysis and inventory analysis to investigate the flows and stocks of Cd in the industry-environment system in mainland China from 1990 to 2015. Special attention is paid to the identification of emissions and corresponding sources. It was found that: (1) more than 63% of Cd input in mainland China comprised unintentional processes that were driven by domestic mining and refining of nonferrous ores, which exceeded the input driven by intentional processes; (2) China became a net importer of Cd in 2000 because of the increasing import of nonferrous ores, which then led to Cd accumulation in domestic solid wastes; (3) Cd resources were mainly consumed in Ni–Cd batteries and plastics, and the in-use stock of Ni–Cd batteries reached a peak in 2008; (4) Cd emissions started to rise in 1990 and remained steady after 2013 due to the relatively stable production of nonferrous ores. The tendency of Cd emissions, use of Cd resources, and development of Cd-relevant industries were also discussed. The results indicated that the utilization of traditional products and the production of new energy materials may become the most important application of Cd resources in China.

A practical, long-term production scheduling model in open pit mines using integer linear programming

SYNOPSIS Long-term production scheduling is a major step in open pit mine planning and design. It aims to maximize the net present value (NPV) of the cash flows from a mining project while satisfying all the operational constraints, such as grade blending, ore production, mining capacity, and pit slope during each scheduling period. Long-term plans not only determine the cash flow generated over the mine life, but are also the basis for medium- and short-term production scheduling. Mathematical programming methods, such as linear programming, mixed integer linear programming, dynamic programming, and graph theory, have shown to be well suited for optimization of mine production scheduling. However, the long-term plans generated by the mathematical formulations mostly create a scattered block extraction order on several benches that cannot be implemented in practice. The reason is the excessive movement of mining equipment between benches in a single scheduling period. In this paper, an alternative integer linear programming (ILP) formulation is presented for long-term production scheduling that reduced the number of active benches in any scheduling period. Numerical results of the proposed model on a small-scale open pit gold mine show a 34% reduction in the average number of working benches in a given scheduling period. Keywords: long-term production scheduling, mathematical programming, practical plans, equipment movements.

ТЕХНОЛОГІЧНИЙ РОЗВИТОК ЧОРНОЇ МЕТАЛУРГІЇ УКРАЇНИ НА СЕРЕДНЬОСТРОКОВУ І ДОВГОСТРОКОВУ ПЕРСПЕКТИВУ

The purpose of the study is to identify current trends in metallurgical technologies, taking into account environmental problems. The world is undergoing major changes in environmental policy, which has become an integral part of industrial policy and international trade. The analysis shows a certain connection between the increase in Earth's temperature and the growth of steel production in the world. Therefore, the Paris Climate Agreement, which was supported by most industrialized countries, is based on the idea of limiting and reducing greenhouse gas emissions by industrial enterprises. On the one hand, industrial emissions undoubtedly affect the ecological state of the environment. On the other hand, a sharp reduction in production emissions significantly increases financial costs. In the world, environmental requirements for metallurgical processes are gaining such a level that threatens the prospects for the development of metallurgy. It is shown that the choice of the optimal path of ecological development requires the search for new solutions to increase the level of implementation of ecological innovations by Ukrainian enterprises. To identify the impact of production technologies of different types of metallurgical products, the method of expert-mathematical evaluation using the Harrington desirability function was used. It is shown that for rolled products the rating means «satisfactory» or «good». The situation with the production of iron ore, pig iron and steel is worse - here a comprehensive assessment shows the value of «unsatisfactory» and «satisfactory». This thesis is confirmed by the fact that investments of ecological orientation of the Ukrainian metallurgical enterprises are now directed on improvement of ecological indicators in the specified directions. Prospects for the development of metallurgy in Ukraine should be associated with the implementation of new technical solutions, in particular those developments that are in the stage of exploratory research and experimental samples. Scientific developments of the Iron and Steel Institute of the National Academy of Sciences of Ukraine, aimed at reducing energy consumption and improving the environmental performance of metallurgical production

МИРОВОЙ РЫНОК РЕСУРСОВ ЦВЕТНОЙ МЕТАЛЛУРГИИ

Since the beginning of the XXI century, the raw material of non-ferrous metallurgy began to acquire new outlines. First, due to the growing demand for resources from the rapidly developing countries of Asia (China, India, South Korea), the volume of world production and international flows of both raw ore and ore dressing – concentrates have increased. Secondly, the concentration of countries that produce raw materials on the one hand and consume them on the other has increased. The article is devoted to comparative statistical analysis of international flows of raw materials of non-ferrous metals. The leading countries in the world exporting non-ferrous metal ores and countries importing them have been identified. The impact of new applications of non-ferrous metals on increasing international trade, such as the expansion of the production of batteries for electromobile and consumer electronics, the development of nuclear energy, etc., is highlighted.

Ore Production Optimization for Constant Grade of Run-of-Mine Feed to the Beneficiation Plant of National Iron Ore Mining Company, Itakpe, Nigeria

Ore Production Optimization for Constant Grade of Run-of-Mine Feed to the Beneficiation Plant of National Iron Ore Mining Company, Itakpe, Nigeria

Justification of underground gold placer development parameters for the Konevinsky deposit

The Konevinsky deposit is located in the Eastern Sayan highlands in a poorly developed area of the Far North. The deposit is being developed by Khuzhir Enterprise LLC. The deposit is a thin steeply dipping vein characterized by the extremely irregular metal content and a low ore-bearing coefficient. Ore is extracted using the underground method at a depth of 300 m in the permafrost zone. Steeply dipping ore deposits with a complex morphology and a discrete distribution of metal are developed using the ore shrinkage system which involves longwall stoping without supporting enclosing rocks. Longwall stoping with a small extraction space eliminates rock cleavage along the cracking system that results in high dilution of ore (up to 67%). Due to this fact, the existing mining geotechnology of balance reserves development has become unprofitable and production has been suspended. The purpose of this article is to identify new parameters of the balance reserve extraction method that will improve quality of ore and increase profitability of metal production. Studies of geological environment and analysis of causes of ore quality deterioration showed that along with the excessive sticking of wall rocks under the minimal excavation width of 1m, ore dilution is affected by inrushes from block sides with an increased rock fracturing and an internal chocking with low-grade ores. These disadvantages can be eliminated using sublevel drifts, the breast-and-bench method and a descending order of reserves excavation. The article substantiates and develops parameters of the system which can increase ore production quality without increasing production costs.

Optimization of Ore Production in Copper Mine

Mining activities are risky operations and represent a significant threat to capital investments. These activities, which require many years of evaluating the technical characteristics of the mineral deposit using the most appropriate method, also require an economic, safety, environmental or other evaluation. In this study, a feasibility study of copper production is proposed to determine the optimal production scale based on three production plans. The mining production scale is based on 4.5 million t/a compared to other projects on the change in quantity, investment and engineering cost when the mining production scale is reduced to 3.5 million t/a and increased to 5.5 million t/a. The results reveal that applying 4.5 million t/a to the mining production project appears to be the optimal choice in terms of economic benefits, both after verification of the production scale in terms of annual decline rate and reasonable mine life. The result also shows that the production scale of 4.5 million t/a is technically more feasible.

Steel in a circular economy: Global implications of a green shift in China

Abstract China is increasingly known for its ambitions towards an ‘ecological civilisation’ and a circular economy. Our article assesses the implications of an accelerated shift towards steel recycling in China. Given the relevance of steel for development worldwide as well as its environmental intensity, any such shift is likely to have implications for competitiveness in China and beyond. Recent findings suggest that China could take advantage of an increasing availability of obsolete steel scrap in the coming decades, moving towards more circular, and potentially greener, steel production. We assess such industrial restructuring from an economic perspective and address the competitiveness of China relative to other developing and industrialised regions. The analysis uses a novel global economy-wide modelling framework (ENGAGE-materials) to assess the aggregate and sector-level impacts of different scrap use options in China in the 2019–2030 time frame. The results show moderate GDP gains for China of cumulated USD 589 billion in GDP gains by 2030 despite a replacement of primary steel capacity. A more comprehensive industrial policy mix aimed at improved recycling practices and more adaptive downstream sectors could increase gains to USD 819 billion. The international implications are mixed, with losses for iron ore producers (Australia, Brazil and India) and gains for most developing countries benefiting from lower steel prices. Another result is an increasing demand for coal in electricity production if such a shift wouldn’t be aligned with an accelerated energy transition towards low carbon pathways. We discuss policy implications of such alignment, potential co-benefits, and a need for green international partnerships.

Endothelial dysfunction in workers in underground mining of chrome ores

Introduction. Currently, endothelial dysfunction is considered as one of the initial stages of the pathogenesis of cardiovascular diseases. By isolating a number of biologically active compounds, the endothelium helps to maintain vascular tone and physiological rheology of the blood. Modern production of chrome ore is characterized by a variety of harmful occupational factors (chromium, dust, noise, vibration, severity and intensity of work, cooling microclimate), which can disrupt the normal functioning of the vascular endothelium and lead to the development of cardiovascular diseases.The aim of the study was to study the features of endothelial function in workers engaged in underground mining of chrome ore in harmful working conditions.Materials and methods. The study included 98 miners of the enterprise for the extraction of chrome ore. The comparison group (working in conditions outside the influence of the studied production factors) consisted of 75 employees-managers and specialists of administrative and managerial personnel of the enterprise, comparable in age and experience with the observation group. To assess the vasomotor function of the endothelium, a flow-dependent (endothelium-dependent) vasodilation test was performed using the D. S. Celermajer technique. Post-occlusive increase in brachial artery diameter, brachial artery sensitivity coefficient to endothelial shift change were evaluated.Results. The endothelial function of mine workers did not differ significantly from the comparison group with work experience up to 10 years (the values of the relative increase in the diameter of the brachial artery 12.2% in the observation group and in the comparison group 12.6%, p=0.74). With experience of more than 10 years, the value of the relative increase in the diameter of the brachial artery in the observation group with experience of more than 10 years corresponded to the signs of endothelial dysfunction and amounted to 8.6%, while in the comparison group this figure was 12.4%, which corresponded to normal endothelial function (p=0.019). Endothelial function progressively deteriorated with increasing seniority in mine workers. Conclusions. For workers engaged in underground mining of chrome ore for more than 10 years, a reduced vasodilation reaction to reperfusion after an occlusion test and a low coefficient of sensitivity of the endothelium to shear stress are characteristic. There was no statistically significant decrease in increase in brachial artery diameter and the coefficient of sensitivity of endothelium to shear stress relative to the comparison group was selected only from persons with experience more than 10 years. The comparative analysis of the results of the evaluation of the functional activity of the endothelium in workers of the compared groups indicates that the change in the functional state of the endothelium in miners is associated not only with age, but also with working conditions. The revealed changes predispose to the development of cardiovascular pathology associated with atherosclerosis in workers of underground chrome ore mining.

Developing the Technology of Regenerative Siderite Ore Roasting in Shaft Furnaces

This paper shows that the existing siderite ore preparation techniques do not allow achieving high blast-furnace smelting levels as compared with using black iron ore concentrates with a high iron content. To make blast-furnace smelting more efficient, it is necessary to use the metallized product made by regenerative siderite ore roasting. The technology developed for this roasting allows producing metallized concentrate with a Fe content of 65–68%. The main provisions of regenerative siderite ore roasting in shaft furnaces are formulated, and the three-zone shaft furnace design proposed for implementing this process. The thermal and consumption parameters of the process are provided as well as the lean gas circuit of regenerative ore roasting. This circuit allows significant cutting the expenses. The metallized siderite ore product with a high iron content allows gaining major economic benefits in blast-furnace production.

Perencanaan Disposal Semi Induced Flow dan Finger Flow di PT Vale Indonesia Tbk, Kabupaten Luwu Timur, Provinsi Sulawesi Selatan

Disposal Planning of Semi Induced Flow and Finger Flow in PT Vale Indonesia Tbk, East Luwu Regency, South Sulawesi Province). PT Vale Indonesia Tbk produces sizable nickel ore, which is an average of 75,000 tons per year and the overburden is around four times the amount of nickel ore production, thus requiring good disposal planning.Disposal planning includes disposal design, allocation of the number of dozers, disposal life length, and disposal costs. The research locations are Watulabu 16C DP and Watulabu 19 DP in West Block Area and Nickel Hill 15 DP and Nayoko 01 DP in East Block Area. Watulabu 16C DP and Nickel Hill 15 DP are semi-induced disposal, while Watulabu 19 DP and Nayoko 01 DP are disposal finger flow. Each disposal has two units dozer. The dozers used are dozer D8R Caterpillar. Disposal planning was made using Maptek Vulcan and Microsoft Excel software. Based on the results of the research, the disposal design of Watulabu 16C DP has a surface area of ​​72,229.40 m2 and a volume of 125,959.92 m3, Nickel Hill 15 DP has a surface area of ​​92,375.68 m2 and a volume of 128,344.04 m3, Watulabu 19 DP has a surface area of ​​129,061.97 m2 and volume of 775,396.21 m3, and Nayoko 01 DP has a surface area of ​​227,318.16 m2 and volume of 1,270,176.94 m3. The disposal life length of Watulabu 16C DP is 1.5 weeks (11 days), Nickel Hill 15 DP is 1.4 weeks (10 days), Watulabu 19 DP is 7.5 weeks (53 days), and Nayoko 01 DP is 11.2 weeks (79 days). The disposal cost of Watulabu 16C DP is $51,841.49, Nickel Hill 15 DP is $138,061.15, Watulabu 19 DP is $370,924.26, and Nayoko 01 DP is $957,625.14.

Correction to: Projection of Iron Ore Production

Correction to: Projection of Iron Ore Production

Improving quality of granulometric composition of potash ore produced by «Ural-20R» heading-and-winning machines

Processes of cutting and movement of potash ore during operation of «Ural-20R» heading-and-winning machines are followed with its breakage leading to the increase of number of non-washable powdered classes (particle size less than 0.25 mm) in the breakage products. The sources analysis of dust-like classes formation during the work of «Ural-20R» machines is performed. The regions of rational (by minimum output of dust-like classes) values of breaking parameters of potassium solid mass in use of checkered and consistent cutting schemes are defined. The analysis of the operating parameters compliance of the planetary-disk operating members of «Ural-20R» machines of various modifications with rational cutting parameters is carried out. Technical proposals on improving the operating members of «Ural-20R» machines by use of the crossed procedure of potassium solid mass breaking are reported. It is proved that the proposed solutions will reduce the number of dust-like classes in the breakage products and reduce the specific energy consumption of the potash ore production processed.

Dust content in the air: A case study of the Afanasyevsky open pit mine (Russia)

According to experts, the world consumption of mineral raw materials and the rocks extraction have reached about 12 and 100 billion tons per year, respectively. Overall Russian coal production accounts for 259.9 million tons (according to the Ministry of Energy of the Russian Federation and the ‘Rosinformugol’ agency), metallic ores are estimated at 230 million tons, and building materials reach 1.4 billion tons. The overall growth in mineral production and capacity of ore producers cause an increase in the negative environmental impact of mining extraction and processing. It should be taken into account that due to the depletion of reserves of rich mineral raw materials, the volume of mined rock mass and the amount of processing waste of mineral raw materials increase. It results in the formation of mine dumps, consisting rocks, ore beneficiation wastes, ashes, slags, and sludge. Research data describe critical environmental situation within the mining enterprises, and especially mine dumps, as a result of massive dust emissions. In addition, there is a tendency to further environmental degradation, due to the increase in production capacity without complying with effective measures to reduce dust emissions. Considering the fact that fine particles are priority pollutants in the extraction and processing of mineral resources at mining enterprises, it is necessary to develop new environmentally efficient and economically viable methods of dust suppression.

Deep Neural Network for Ore Production and Crusher Utilization Prediction of Truck Haulage System in Underground Mine

A new method using a deep neural network (DNN) model is proposed to predict the ore production and crusher utilization of a truck haulage system in an underground mine. An underground limestone mine was selected as the study area, and the DNN model input/output nodes were designed to reflect the truck haulage system characteristics. Big data collected on-site for 1 month were processed to create learning datasets. To select the optimal DNN learning model, the numbers of hidden layers and hidden layer nodes were set to various values for analyzing the training and test data. The optimal DNN model structure for ore production prediction was set to five hidden layers and 40 hidden layer nodes. The test data exhibited a coefficient of determination of 0.99 and mean absolute percentage error (MAPE) of 2.80%. The optimal configuration for the crusher utilization prediction was set to four hidden layers and 40 hidden layer nodes, and the test data exhibited a coefficient of determination of 0.99 and MAPE of 2.49%. The trained DNN model was used to predict the ore production and crusher utilization, which were similar to the actual observed values.