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By E. V. Bratygin, E. G. Dmitrieva

The aim of the research was to study the thermodynamic characteristics of high-temperature processing of ilmenite concentrate deposits "Central" in a neutral and oxidizing atmosphere, as well as its interaction with alkaline additives. The research was conducted using a scanning colonoscopy on thermogravimetrical analyzer NETZSCH STA 449 F3. A sample of the test material weighing 10 mg was placed in a crucible and heated at a rate of 10 °C/min to 1200 °C in argon or air. Studies have been conducted pure ilmenite concentrate and its mixtures with 5 % and 12.5% of sodium carbonate. The results of the analysis of the thermogravimetric curves it was found that the recovery of the concentrate carbon will come from ulvospinel, not pseudobrookite, and the reaction recovery is possible at temperatures above 900°C. While removing produced in the decay ilmenorutile of iron oxides in an inactive form, for example, iron (III) oxide, it is possible to reduce the quantity of the solution of ilmenite formed during the restoration of the melt anosovite. The analysis of data obtained during heating of ilmenite concentrate with sodium carbonate in concentrations of 5 and 12.5% transition pseudobrookite in ulvospinel is missing, it just breaks down into hematite and titanium oxide, which, in turn, react with N?2??3. It should be noted that increasing the concentration of sodium carbonate in the sample contributes to more complete interaction of iron oxides and N?2??3 with formation of ferrites of sodium. This can ensure full recovery of iron oxides in the concentrate, which is part of secondary ilmenite can not be dissolved in the melt formed by the lower oxides of titanium. In addition, the increase in the content of soda in the mixture significantly reduces the temperature of the initial melting point of the slag and facilitates the coagulation of metallic iron.The obtained results were used for laboratory studies of the solid-phase sintering of briquettes from ilmenite concentrate with additives of sodium carbonate and a reducing – coal, as well as for the development of technological mode of solid-phase sintering of the concentrate with the aim of obtaining product recovery with a titanium dioxide content of more than 75 %.

Jan 1, 2018

By Lilong Huang, Yuan Long, Li Shi, Guowang Zhang, Xiao Xiao

"Graphite is the key raw material of new carbon materials such as graphene and spherical graphite. The size and completeness of graphite flakes directly affect the performance of new carbonaceous materials.The research aims to increase the yield of large flake graphite by way of preventing the flake graphite from being damaged during the grinding process. A series of grinding and flotation studies on the flake graphite samples of Yichang in Hubei Province were carried out by vertical stirred mill . The damage coefficient L characterising the degree of graphite flake fractured and corresponding formula was proposed to determine the quality of the grinding and grinding of the flake graphite. The way the damage coefficient L of graphite flake would be affected if with different mill, different media material and size, stirrer speed were investigated. The test results show that vertical screw stirred mill helps the protection of large flake of graphite as well as the graphite liberation. When grinding to the same fineness, the damage coefficient L of graphite flake is 1.20 for vertical stirred mill, while the damage coefficient is 2.93 for ball mill. Minimum damage coefficient of graphite flake was obtained when using 6 mm polyurethane coated ball as grinding media, under the condition that rotation speed of the stirrer within the range of 100~130r/min. The grade of graphite in the concentrate floated from the ground product was 94.16%, the rate of recovery for graphite was 94.66%, and the content of +0.15mm was 54.83%.1 INTRODUCTION Flake graphite is a very important non-metallic mineral[1,2],and due to its special flake structure, the greater the scale and the higher the C grade, the value of its application is larger too. Therefore, in the grinding of graphite sorting process, We should minimize the destruction of graphite scales.. In this paper, graphite mine in Yichang, Hubei Province was used as the raw material for the study. Rough concentrate with C-grade of 36.49% was prepared by rough grinding and coarse separation. Then a series of grinding and flotation studies on the rough concentrate were carried out by vertical stirred mill , which aims to increase the yield of large flake graphite and to provide technical support for improving the beneficiation process of graphite ore."

Jan 1, 2018

By S. M. Bradshaw, R. Smith, J. H. van Vreden, C. A. Snyders

"The re-treatment of gold tailing heaps has shown to be a potentially significant revenue stream for both large and small scale gold companies. Limited access to capital and lack of skilled labour remain restrictive especially when dealing with a refractory ore and/or where limited amount of material are available. Alternative techniques such as low temperature pre-leaching options to unlock value are therefore in demand. Several low temperature pre-leaching experiments in acidic and alkaline solutions, followed by cyanidation were performed which ultimately led to the further investigation of a caustic pre-leaching step. It was found that the Au recovery from a refractory ore tailings heap could be significantly improved from ˜ 15 to 20% to greater than 60% with a simple atmospheric NaOH pre-leaching step. It was further considered, that since the NaOH pre-leach liberate the Au associated with refractory sulphide minerals, the overall process may benefit by the inclusion of a froth flotation step to separate refractory sulphides from the free milling ore. Froth flotation on weathered tailing heaps are, however, known to be difficult, ultimately resulting in poor recoveries. A process flow sheet, incorporating a caustic pre-leaching step and a process which includes flotation and caustic pre-leaching of the concentrate, are technically evaluated and ultimately compared to simple cyanide re-processing. INTRODUCTION South Africa consists of a large number of gold tailings dumps. Janse van Rensburg (2016) estimated that there was about 517 dumps in the Gauteng area, covering approximately 320 000 ha of surface area. Recovering value from the dumps has received a great deal of interest but can be problematic due to the dumps often being refractory, preg-robbing and weathered. High recovery of valuable metals (Au and Ag) are possible (Fleming and Brown, 2010) but would most likely require pressure oxidation and subsequent neutralisation which can be very capital intensive demanding a high skill set to operate and maintain. In addition, these flowsheets target high processing tonnages due to the economy of scales at the lower grade feed materials, further increasing the capital requirement."

Jan 1, 2018

By A. H. Mumin, A. Prikhodko

"This paper provides an understanding of interpreting and evaluating airborne time domain electromagnetic (TEM) surveys as applied to massive sulfide exploration. Variations in the conductive morphologies of massive sulfide ore systems are discussed, followed by forward modelling exercises examining the derived TEM response to these morphologies and discussion of the subtleties of data interpretation. Deposit morphology in the orientation at formation and the variations occurring due to later deformation are considered. Images of corresponding resistivity–depth models are provided. The combined modelling results provide a low-cost method for initial interpretation and screening of TEM anomalies. RÉSUMÉ Cet article nous permet de mieux comprendre l’interprétation et l’évaluation des levés élec-tromagnétiques aéroportés en domaine temporel (TDEM, de l’anglais time-domain electromagnetic) appliqués à l’exploration du sulfure massif. Y sont débattues les variations au niveau des morphologies conductrices des systèmes de minéralisation du sulfure massif, suivies d’exercices de modélisation prospective qui examinent la réponse dérivée des TDEM à ces morphologies et d’une discussion sur les subtilités de l’interprétation des données. L’étude envisage la morphologie de l’orientation originelle non déformée des gisements ainsi que les variations résultant d’une déformation ultérieure. Des images des modèles correspondants de résistivité-profondeur sont fournies. Les résultats combinés relatifs à la modélisation proposent une méthode peu onéreuse d’interprétation et de contrôle initiaux des anomalies dans les TDEM.INTRODUCTION Electromagnetic geophysical surveys are an indispensable foundation of many mineral exploration programs and can account for as much as half of the predrilling exploration costs. Quantitative mass interpretation of the survey results remains difficult due to the infinite variation of deposit morphologies, their complex physical properties, and the presence of barren conductive materials that can mimic or mask the response of targeted ore. Many modern geophysical investigations that focus on time domain electromagnetic (TEM) data interpretations are devoted to problems with inversion and modelling and their algorithms. Although a few of these investigations have resulted in commercial software products, these require highly qualified and experienced users and usually include geometric assumptions. Furthermore, without the input of known physical properties and geometric constraints, the inversion results are highly ambiguous. A number of case studies document the geophysical responses to known targets in well-defined and diverse geo-electrical environments, providing a high degree of correlation between field obser-vation and the results of the modelling used in this style of investigation (Hone, 1980; Schneider & Emerson, 1980; Tyne, Idnurm, & Malone, 1981; Bishop & Lewis, 1992; Hopgood & Hungerford, 1994; Meju, 2002; Yang & Oldenburg, 2016). The uniqueness of the target/environment parameters and their specific features limits the use logy is poorly understood. The responses are therefore that are devoid of complicating environmental factors (e.g., highly conductive overburden and hostrocks or nonuniform target conductivity) as a first approach to the interpretation process of such case studies as the main reference for interpreting TEM survey responses in areas where the underlying geomodelled from generalized and typical geological models"

Jan 1, 2018

By W. D. Guo, Y. M. Zhu, B. B. Luo

The main chemical constituents of waste cooking oil are higher fatty acid glycerides, which can be used to produce anionic fatty acids for most non-sulfide flotation. However, using the mixed fatty acids (MFA) produced by waste cooking oil as collectors directly, the flotation effect is usually not satisfactory, especially at lower temperature or room temperature. There are very rare systematic studies about the reason for poor flotation performance of waste cooking oil. This study aims to investigate the flotation and adsorption characteristic of different types of fatty acids in waste cooking oil to find out what kind of fatty acids results in the poor flotation performance. This will provide technical supports and theoretical guidance for the waste cooking oil application in the field of mineral processing. In this study, MFA were produced from the waste cooking oil, and then separated into saturated fatty acids (SFA) as well as unsaturated fatty acids (UFA), which possessing different flotation properties. The properties of the MFA, SFA and UFA were analyzed by iodine value, melting point measurement, Fourier transform infrared (FT-IR) spectroscopy and quartz micro-flotation tests. The results showed that UFA was composed of fatty acids containing group—(CH=CH—CH2)n—, having an iodine value of up to 162.90, a melting point as low as -17.3 ? and stronger low-temperature floatability. In contrast, the SFA was made up with saturated fatty acids and a few oleic acids, with an iodine value of 48.97 and a melting point of 38.8 ?. SFA had shown poor collectability and required a flotation temperature higher than 35 ?. The results of zeta potential measurements, solution chemistry calculation and FT-IR spectra revealed that both UFA and SFA can be adsorbed on the quartz surface activated by CaCl2 via the chemical and hydrogen bonding. The reason MFA having a poor flotation performance is the SFA has an extremely high melting point which affecting the dissolution of the dispersion.

Jan 1, 2018

By U. A. Peuker, T. Mütze, F. Shayo, A. Wikedzi

"Buzwagi Gold Mine (BGM) is operated by Acacia Mining and located in the Lake Victoria Goldfields of central Tanzania. The mine treats a sulphide copper-gold ore to produce gold in form of doré bars and a concentrate containing gold, copper and silver. The BGM comminution circuit includes a primary crushing stage with a gyratory crusher and two grinding circuits using a Semi-Autogenous Grinding (SAG) mill and a ball mill. Currently, the grinding circuits are inefficient in achieving the aspired product fineness of xP,80 = 125 µm even at low to normal throughputs (450-600 t/h). An optimization study of the circuit performance was conducted to improve product fineness through circuit surveys, experimental lab work and simulations. The analysis of survey data revealed inefficient grinding operation characterized by ball mill product (xP,80 > 400 µm) coarser than designed and higher hydrocyclone cut sizes (xT > 200 µm), too. In MODSIM several options were simulated such as reduction of vortex finder and apex diameters, reduction of SAG screen aperture, and modification of cyclone feed density. An improvement of product fineness could be achieved by simulation of the cumulative changes but it was also concluded that the current equipment cannot achieve the target. Further simulations showed that a second ball mill might help to achieve the desired fineness as well as an increase of grinding throughput by up to 26 %. INTRODUCTION Simulation of comminution, particularly grinding and classification, has received great attention for many years, due to the fact that the unit operation is by far the most important both in terms of energy consumption as well as overall plant performance (King, 2001; Wills et al., 2006). The use of simulation is advantageous due to low cost as well as its ability to consider many variables simultaneously. Moreover, there are some benefits for optimizing grinding operations by simulation like decreased unit operating costs, increased capacity, and improved performance of downstream processes due to improved feed size distribution. This paper presents an optimization study for the grinding efficiency at Buzwagi Gold Mine. This was achieved through three full scale circuit surveys, lab work and simulations with MODSIM."

Jan 1, 2018

By Federico Pagliacci, Marco Chiarabelli, Salvatore Miranda

The paper describes the adopted technologies and performance controls related to a special geotechnical engineering solution provided within the scope of the Galataport Project, in Istanbul, Turkey. The scheme is the one applied to the new quay of Salipazari, which is a combination of retaining structure and ground improvement, formed by a combi-wall, a reinforced concrete diaphragm wall and a soil improvement by deep soil mixing (Turbojet). The paper highlights the importance of employing cutting-edge technologies within the foundation engineering field and state-of-the-art electronic control devices, in parallel with the essential human expertise, in order to obtain the desired results in this high profile Project. The results of the in-situ and laboratory tests carried out on the improved soil are also presented. Main discussed points are: • History of Galataport and main Project details. • Design principle and soil condition for the new quay of Salipazari. • Difficulties encountered during execution of DSM. • Preliminary field trial tests conducted to establish the operational parameters, with relevant in-situ and laboratory tests executed. • Preliminary tests on material used for DSM (seawater and CEM IV SR). • Electronic equipment mounted on the rig, which allows the automatic execution of DSM columns. • Final QA/QC tests conducted to verify the performance of DSM, mainly consisting in: coring with relevant laboratory tests on samples (UCS + Es), seismic refraction tomography and seismic cross hole tomography. Correlations between UCS and Es, and between Es and Edyn are also presented. • A cross section of the executed treatment could be inspected on site during excavation. Photos and considerations are also presented.

Jan 1, 2018

By B. Li

"Sepiolite is a magnesium-rich, porous, and fibrous clay mineral with broad applications. These applications take advantage of sepiolite’s high specific surface area and unique nano-sized channel structure. Over the past years, numerous materials and techniques based on the structure and property of sepiolite have been developed. This article reviewed the recent achievements in developments and applications of sepiolite in environmental protection, catalysis area, and nanocomposites. The prospectives of sepiolite applications is also discussed. INTRODUCTION Sepiolite is a magnesium-rich, porous, and fibrous clay mineral. The typical chemical formula of sepiolite is Si12Mg8O30[OH]4[OH2]4·8H2O [1]. Sepiolite has a high specific surface area and nano-sized channels because of its special structure [2]. This unusual crystal structure projected onto the [001] plane is shown in Fig.1 [3]. As it can be seen, silicon and oxygen atoms make up for the tetrahedral structure and magnesium and oxygen atoms form octahedral structure, respectively. Those tetrahedral-octahedral-tetrahedral ribbons expand boundlessly in one direction, leading to the special fibrous structure of the sepiolite. Every tetrahedral-octahedral-tetrahedral ribbon is combined to the next by an inverted Si–O–Si bond, which causes an interlaced layer with a continuous tetrahedral sheet and a discontinuous octahedral sheet. Terminal MgO at the edges of the ribbons is coordinated with two structural water molecules, which can form hydrogen bonds with zeolitic water molecules that are located in the channels running parallel to the fiber axis [3,4]. The Mg2+ ions inside the channels can be exchanged with other cations in solution. Therefore, sepiolite can be used to remove metal cations from aqueous solutions [5,6].It can be seen from Figure. 1 and Table 1 [7], the unique structure endows sepiolite with a substantial surface area and nanoscale channels. Its specific surface area reaches 320 m2/g and channel dimensions up to 3.7×10.6 Å. There are three active adsorption sites on the surface of sepiolite: one is oxygen atoms of the Si-O tetrahedron. The second is the structural water molecules paired with magnesium ions at the edges of the ribbons, which can form hydrogen bond with adsorbent. The last one is the Si-OH groups due to the breaks of the Si-O-Si bonds on the surface of Si-O tetrahedron. Thus, sepiolite has strong adsorption ability which has been widely used in environmental protection. Moreover, sepiolite has many significant features such as good mechanical and thermal stability, rheological property, porous, and easily modification, making it be a hotspot in chemical and biological researches. However, with the development of technology, broader and more advanced applications of sepiolite have been carried out in recent years. In this study, the recent achievement in sepiolite applications is summarized, the further tendency is also discussed."

Jan 1, 2018

By A. V. Myaskov, V. S. Valavin, K. D’Elia, I. O. Krylov, Vu Van Toan, T. I. Yushina

"The purpose of this research is the development of a technology for processing the concentration tailings of limonite ores at Kamysh-Burun Mining and Processing Complex into an iron- containing product for ROMELT process. In the concentration and metallurgical processing of iron ores, substantial amounts of waste are generated (tailings, slimes, slags, metallurgical dust, etc.) that can be converted into a commercial product if is properly processed. This article presents the results of experimental studies of the feasibility of processing iron- containing tailings of Kamysh-Burun deposit (slimes from Verkhne-Churbash storage facility (VCh sample) and dumped waste of Kamysh-Burun (KB sample)) to obtaining valuable components for further uses. Applying Mossbauer spectroscopy has been shown that the iron minerals in the studied samples are technogenic varieties of iron hydroxides. The most suitable technology is the magnetic roasting process, since iron hydroxides are easily transformed into a magnetic, easily recoverable form. Have been shown the advantages of a two-stage magnetic separation, in a strong field and with polygradient separators. Concentrating this material through magnetic methods makes it possible to increase the iron content to 20-21 %. Magnetic concentration of the deeper layers materials results in iron- containing concentrates with a total iron content of up to 58% whit a phosphorus content of about 2%. Reducing the phosphorus content is possible by blending upper and lower layers of the material at a ratio of 1:1. Thus, it is possible to process the material accumulated in the slime storage facility using the ROMELT process combined with preliminary three-stage magnetic concentration and disposal of tailings with the permissible iron content of less than 5%. Wastes from smelting will be slags suitable for use in construction industry. The Kamysh-Burun material preparation for ROMELT process should be performed applying gravity-washing with separation of the -0.4 mm fraction and additional blending for dephosphorizing the concentrate. The smelting will produce pig iron and slag."

Jan 1, 2018

By V. Runkana, N. K. V. Nadimpalli, S. Sahu

"IsaMill™ has been in operation in the recent past for fine grinding of low grade ores to extract non-ferrous minerals. IsaMill™, typically, consists of a series of uniformly spaced identical disks mounted on a rotating shaft which is encased in an outer shell. The mill offers high energy efficiency for fine grinding and an inherent scalability. But, it encounters certain operational challenges such as non-uniform distribution of grinding media coupled with high wear rate of the disks and solid walls of the mill at specific locations—which adversely affect the mill performance. To circumvent these operational challenges, design modification of the disks through heuristics, by introducing a reduced diameter disk (RDD) at specific locations, is a common practice in industry. But there is no systematic scientific study in this regard. In the current work, we developed a discrete element method (DEM) based model and simulated for the IsaMill™ operation to study the effect of RDD on the efficiency of the mill and wear rate of the solid walls and disks. Since the first set of disks experience the high wear rate due to the high loading of the charge, the RDD was introduced at the first two disks. The simulations were performed at different diameters of the RDDs and at different media loadings. The performance of the mill was analyzed based on the power consumption, the wear rate on disks and the distribution of media particles inside the mill. Besides, the performance variables such as mean velocity of media particles and total impact energy provided useful insights into the milling operation. It was observed that the reduction in disk diameter yields lower wear rate of the disks at the cost of decrease in power draw at a constant high media loading. Whereas, when the media loading was decreased, the amount of wear and power drawn was comparable for both the most reduced and least reduced disk diameters. Therefore, there is an optimum choice of RDD for a given mill loading to maximize the mill performance while reducing the wear rate of the disks."

Jan 1, 2018

By Ivar Eskerud Smith, Ole Jørgen Nydal, Niranjan Reddy Challabotla, Svein Sævik

INTRODUCTION Airlift pumping, utilize compressed air that is injected at the bottom of a vertical pipe submerged in the water, reduces the mixture density inside the pipe and lifts the liquid or mixture of liquid and solids. This type of pumping technology, which is simple and without moving parts submerged in water, which provides several advantages compared to the mechanical pumping. Airlift is used in various difficult pumping applications such as transport of fluids corrosive to metals, explosives, nuclear and toxic materials in chemical industries, diamond mining and coal transport. Application of airlift to deep sea mining conditions was investigated by extensive laboratory experiments [1], theoretical analysis [2], and limited proof of concept field studies [3] starting in 1970’s with the discovery of huge amounts of manganese nodules discovered on the seabed at a depth of ranging from 4000 to 6000 m . Even after extensive investigations over the last five decades, there exists no commercial application of airlift technology for lifting of minerals. The major problems with the application airlift for deep ocean mining was (a) lack of control over the expansion of the injected gas, which increases the velocity in upper part of the riser pipe (b) lower efficiency compared to mechanical pumping [3]. Different flow regimes are encountered in airlift pumping: bubble, slug, churn and annular flow. Annular flow regime is the least efficient in lifting of particles and churn flow has better efficiency [3].

Jan 1, 2018

By M. McClintock

"High Pressure Grinding Rolls (HPGR) is increasingly being chosen for comminution circuits for its energy-efficiency for hard rock mining operations. Despite HPGR’s growing popularity, geo-metallurgy programs are still prohibitively expensive because of large sample requirements. Traditionally, sizing HPGR application requires a significant amount of sample, in the order of 1 to 10 tonnes, depending on the level of study and complexity of the resource. Therefore, engineering and design of HPGR circuits typically are reliant on few composites that are required to be representative of the resource and mine plan. Three bench scale HPGR test methodologies were developed in 2015 at NBK Institute of Mining Engineering at the University of British Columbia (UBC) capable of defining the energy size breakage relationship of pilot HPGR. These methodologies were developed to allow bench scale testing for different levels of study from PEA (Preliminary Economic Assessment) to detailed design and operations. The Piston Press test defines the energy size reduction relationship by measuring specific energy consumption and corresponding feed and product size distributions. The advantage of Piston Press testing is the small sample requirement of 5 to 10 kg. Small sample requirements allow multiple samples to be tested across a deposit. Piston Press testing allows extensive geo-metallurgy programs that can determine ore variability and inform in optimization and production planning. To date, the Piston Press methodologies have been validated on a pilot-scale HPGR unit located at UBC. Recently, testing was conducted to calibrate and validate the Piston Press test against full-scale HPGR on a gold sulphide ore deposit. The program included the collection of operational data with the respective HPGR feed and recycle sample. Sample collected was used both for Piston Press testing and HPGR piloting. This paper discusses the test-work and results as carried out during this program, using the aforementioned methodologies."

Jan 1, 2018

By Y. Idrogo

Electronic delay detonators have been used in most types of blasting application with great success, with the accuracy and precision being used effectively to control negative environmental impacts like vibration. They have also provided consistent repeatable fragmentation and heave results. With the very wide choice in delay period and powerful timing design software, the choice of firing times to optimise blast results is not always clear to the designer. So the improved results achievable from the use of electronic delay detonators are often not optimally achieved.

Jan 1, 2018

By Jeff Jackson, Paul Axtell, David Graham

The Montana Department of Transportation recently awarded a contract to construct a replacement bridge across the Clark Fork River in Heron, MT. Both abutments and both intermediate bridge bents were to be founded on 6-ft and 8-ft diameter, permanently cased drilled shafts with rock sockets, respectively. Two drilled shafts per substructure location were designed for a total of eight drilled shafts. The original design included 6-ft diameter drilled shafts at the abutments but the Contractor elected to submit a Value Engineering proposal that increased them to 8-ft diameter. On the basis of the subsurface exploration program, extremely challenging subsurface conditions were known to exist, including the potential presence of large boulders within the predominantly sand and gravel soil matrix. The successful bidder elected to use an oscillator to install the permanent casing to the top of bedrock, while simultaneously removing the spoils from inside the casing with a clam-grab. On seven of the eight shafts, this approach worked well. Unfortunately, on one of the shafts, the casing met refusal on one or more boulders encountered in the predominantly sand and gravel soil overburden. Following several attempts, and despite several variations of approaches, it was determined that the casing could not be advanced beyond the obstruction without unacceptable risks to the pile-supported temporary work trestle (i.e., loss of soil and reduction in pile capacity for the foundations supporting the work trestle). To mitigate the problematic drilled shaft, a unique solution was designed and successfully constructed. The solution involved the construction of seven 16-in diameter micropiles constructed within the confines of the obstructed casing. The micropiles were drilled to bedrock through the sand, gravel, and boulders and include rock sockets to satisfy axial design requirements. The micropile casing thickness, grade and grout strength were designed to provide adequate flexural strength as well as to satisfy other design requirements. Upon completion of the micropile installation, the upper portion of the drilled shaft above the boulders and within the permanent casing was constructed as usual. This paper discusses the difficult subsurface conditions at the site, the drilled shaft construction difficulties, and the design and construction of the micropile solution.

Jan 1, 2018

By D. Vega, P. R. Brito-Parada

"Small diameter (10 mm) hydrocyclones have been applied successfully for the separation of particle suspensions in the micron size range. These hydrocyclones are attractive because they show a bypass fraction larger that the water recovery, resulting in a high particle recovery to the underflow as well as low water recovery. However, this is a disadvantage when the purpose of the hydrocyclone is classification because of the large amount of fine particles that are misplaced in the underflow. The aim of this study is to explore, experimentally and computationally, the influence of design parameters on the classification process. In this work, a full factorial experimental design was defined to carry out comprehensive experimental tests using glass beads (0-20 µm) as the particulate system. We show that the dimensions of spigot and vortex finder diameter can be effectively manipulated to change the separation performance of the system and the energy consumption. A CFD model was developed that is able to predict particle size distribution. The numerical results for the partition curves showed very good agreement with the experimental data. INTRODUCTION Small diameter hydrocyclones are a very attractive separation technology for fine particle suspensions. Since the hydrocyclone diameter is directly proportional to the cutsize that can be achieved, 10mm hydrocyclones have been shown to be very effective in collecting particles in the micron-size range. In addition, while in large hydrocyclones the bypass, i.e. the fraction of particles that report to the underflow without classification, is similar to the water recovery, in 10mm hydrocyclones the bypass fraction is considerably larger than the water recovery. Its high particle recovery and low water recovery makes small hydrocyclones ideal for ultrafine particle classification and dewatering applications in mineral processing. The separation of mineral suspensions achieved using small hydrocyclones has been the focus of various studies. Pasquier and Cilliers (2000) derived a general classification model from experimental data of fine silica concentration in 10mm hydrocyclones; the model was able to describe the fish-hook partition curve. The effect of operating conditions has also received some attention in the literature. Cilliers et al. (2004) showed that an increase in temperature positively effects the recovery of fine silica particles in small hydrocyclones, by increasing the bypass and decreasing the cutsize. Neese et al. (2015) showed that the cutsize in 10mm hydrocyclones can be further decreased by operating at higher pressure, which also trebled the throughput."

Jan 1, 2018

By V. A. Zhilina, I. V. Shadrunova, O. E. Gorlova

"The aim of the study is to develop and scientifically justify a new adaptive approach to the separating processes of deep and complex processing technogenic mineral raw materials. Technogenic mineral resources as a waste of mining and processing industry are mostly complex objects that have specific features of material composition and technological properties and make it processing ineffective with traditional schemes of mineral raw materials enrichment. Mineral wastes are regarded in this study as a complex object with a large number of signs in conditions of uncertain environment and object. However, adaptation is regarded as the process management system’ adaptation to the specific the properties of the object and the environment that has several hierarchical levels corresponding to different stages in the management of complex object. An adaptive approach is considered as a methodological basis of multivariate schemes for opening the mineral resources and creating mechanisms that could transfer these potential technogenic resources to the actual that significantly expand the mineral resource base of the country's black, coloured, rare, noble metals and construction materials. In this case, potentially the solution to the most pressing social and environmental problems associated with the adverse effects of past economic activity simultaneously with the commercial objectives. This approach to the wastes mining and related processing manufacturers meets the core idea of sustainable development as the balance of interests of State, society, business, private enterprise and each person in the areas of rational use of resources, economic efficiency and environmental safety. On the example of metal-containing raw materials in the form of slags of ferrous and nonferrous metallurgy, ferrous metallurgy sludge, mature fine tailings, the application of adaptive approach illustrates to the development of technologies of its deep and complex processing as phased, thoughtful movement from a comprehensive study of technogenic raw materials to build optimal topologies of technological schemes for processing the mineral wastes. INTRODUCTION Involving the Russian economy in the system of global economic relations significantly changes the nature of the country's competitiveness in the development of the world market and urgently requires competent management of its own natural and mineral resources. The latter at the present time in real economic processes cease to be a passive material foundation and become the producing basis in the production processes in the status of so-called natural capital. Introduced in the field of economic theory at the end of the 20th century, this term means both the flow of natural services and real natural resources. Consequently, natural objects, which act as natural resources of a certain production, today must necessarily be evaluated in a strategic sense. Modern standards of sustainable development presuppose that the economy should equally be oriented to balance the interests of the state, society, business, individual enterprise and each person in the spheres of rational use of resources, preservation of healthy ecosystems, ensuring well-being, high quality of life and environmental safety of not only the current generation, but also respect for the rights of future generations, that is, intergenerational equality. Most types of minerals are classified as non-renewable resources, therefore resource-saving in the sphere of mineral and raw materials complexes is one of the most important factors-indicators characterizing the degree of approximation to the model of rational subsoil use, and, consequently, sustainable development (State Report, 2017)."

Jan 1, 2018

By I. Yochev, A. A. Metelev, A. I. Stepanenko, A. P. Purgin, M. G. Viduetsky, A. M. Panshin, I. F. Garifulin

"Pneumatic flotation cells of the KFM series are intended for the concentration of various ores and technogenic materials. The key operating principle of the flotation cells of the KFM series is the preparation of pulp for flotation in blowers, offering the advantage of an accelerated flotation process. This report summarizes the results of the implementation and operation of the KFM cells at Russian and foreign projects in 2015-2017. Their implementation and operation experience confirms the high efficiency of the KFM cells, especially in the head of lead and zinc, copper and zinc, copper flotation processes:head KFM-600 flotation cell recovers from lead-zinc ore (Rudmetal AD modular concentrator) up to 52% of lead in a single stage (without cleaner flotation) in a salable lead head concentrate (grade of up to 76% lead, 2.3% zinc). The flotation cell proved to be much more efficient than originally expected in the process description in the design phase,flotation of the copper-zinc ore from Novo-Shemur deposit (PJSC Svyatogor concentrator) in two KFM- 1400M cells recovers up to 65% of copper and 70% of zinc in a high-grade bulk copper-zinc concentrate containing 12-13% of copper and 25-28% of zinc. The installation of the two cells with a combined capacity of 26 m3 allowed to decommission 4 chambers of FPM-16 pneumomechanical flotation cells with a combined capacity of 64 m3 with a simultaneous increase in the overall ore concentration performancea single KFM-1400M cell (13 m3) recovers from the copper ore from Volkov deposit (PJSC Svyatogor concentrator) 53% of copper into a high-grade copper head concentrate (33.0% of copper). For comparison, the pneumomechanical cell FPM-16 (capacity 16 m3) has almost half as low copper recovery (29.6%) into the head concentrate at a lower grade (30.5% copper)."

Jan 1, 2018

By Ralph E. Burnham, Jeff Taylor, Jonson Montgomery, J. Kelly Ratliff, Rennie Montgomery, Martin Brashear

Top priorities for all blasting companies and individual blasters are risk management, safety of company personnel and the general public, regulatory compliance, and liability protection. On a daily basis, hundreds of shots are detonated by well-trained, skilled, and experienced blasters without incident. Unfortunately, accidents inevitably occur, which is why blasting is considered an “ultra hazardous” or “inherently dangerous” activity from a legal perspective. Despite countless regulations, recent advances in technology, improved training, ongoing research, and improved communication in the industry, mistakes and the resulting incidents continue to occur during blasting operations. These result in dangerous or deadly flyrock, site security lapses, increased complaints, blast damage claims, and lawsuits, which lead to increased insurance costs and other financial tolls for blasting companies. In life, lessons learned the hard way are rarely forgotten. The same is true in blasting operations. Blasting missteps and the resulting events are often the best catalysts for improving risk management and thereby reducing accidents, liability, and financial tolls. This paper provides a summary of two incidents, one safety and the other liability related, and the errors that resulted in a fatality in one case and a multi property lawsuit in the other. The two incidents provide examples that serve as a case study for lessons learned the hard way in blasting operations and offer guidance for the considerations that blasters and blasting companies should incorporate into daily operating procedures.

Jan 1, 2018

By Sergey Dyachenko

"Following the adopted strategy for making the production modern, efficient and environmental friendly the Company completed a stage of the integrated program aimed at reconfiguration of its processing capacity.Upgrade of the Talnakh Concentrator with commissioning of two start-up facilities (SF) allowed an increase of 30% in its ore processing capacity up to 10 mtpa. In addition to a new high-tech equipment installed, a new concentration process was adopted offering the main advantage of 25-30% reduction of sulfides in concentrate. New concentration technology enabled the total amount of produced nickel concentrates (from Norilsk and Talnakh Concentrators) to be processed at upgraded smelting facilities of Nadezhda Metallurgical Plant and allowed decommissioning of smelting capacities of Nickel Plant resulting in emissions reduction by 30%.Nornickel plans to boost the capacity of Talnakh Concentrator to 18 mtpa by 2022, after commissioning of the 3rd SF. This will provide a shorter route for ores transportation from Talnakh mines along with improvement of cost/performance ratio of ore processing through the usage of the modern equipment and optimized concentration flow scheme. Total capacity of Talnakh Concentrator will be sufficient to process ores from Talnakh deposits with planned upstream assets development taken into account. Volume of ore mined from Norilsk deposits to be processed at Norilsk Concentrator will be also increased.Upgrading the crushing section at Kola MMC Concentrator in 2015 provided finer particles of the crushed ore, resulting in 6.6% increase in specific capacity of ore mills as well as 1% higher recovery of non-ferrous metals due to improved liberation of ore minerals.In 2015-2017 the Company was actively engaged in optimization of existing process flow schemes and parameters of Kola MMC, new high-performance reagents were adopted for concentration process, namely, collectors, depressors, flocculants. These measures allowed the Concentrator to reduce its annual operating unit costs and ensure sustainable production of concentrate with the lower grade of the incoming feedstock.Launched in October 2017, Bystrinsky GOK’s Concentrator was 3D designed and received a range of advanced technological solutions.All design process procedures and technologies rolled-out at the Company’s concentrators were developed by Russian R&D institutes, with the key role of Gipronickel Institute, R&D Service of Kola MMC and Polar Division's in-house Engineering Support Centre."

Jan 1, 2018

By Lebeau M., P. Duguay

"The cost of occupational injuries and diseases in the mining industry in Quebec was estimated for the period of 2010 to 2012. The method used takes into account the financial and human costs assumed by employers, workers, and the community. To better direct research and prevention toward issues with the most significant consequences, the results are presented in various ranking tables, which stakeholders might find useful.RÉSUMÉ Le coût des accidents du travail et des maladies professionnelles dans l’industrie minière au Québec a été estimé pour la période 2010-2012. La méthode utilisée prend en compte les coûts financiers et humains endossés par les employeurs, les travailleurs et la communauté. Afin de mieux orienter les recherches et la prévention vers les problèmes ayant les plus graves conséquences, les résultats sont présentés dans divers tableaux de classement, qui seront d’une grande utilité aux parties prenantes. INTRODUCTIONThe mining industry is much safer today than it was 30 or 40 years ago, mainly due to a more qualified workforce, the use of automated equipment, and a corporate culture more focused on occupational health and safety (OHS); however, the number and the severity of occupational injuries and diseases continue to make this industry one of the most hazardous. In the province of Quebec, the mining industry accounts for approximately 0.4% of paid workers but is the source of 4% of fatal work accidents. It is, therefore, important to continue the prevention efforts already underway in the mining industry.The difficult global economy, which has affected the mining industry in the last few years, is an opportunity to reaffirm that sound management of OHS can have a positive impact on companies’ productivity and profitability. Occupational injuries and diseases are costly for the companies concerned and for society as a whole. Reducing their occurrence makes it possible to reduce not only the size of workers’ compensation board contributions but also several other financial and human costs."

Jan 1, 2018