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By Osvaldo A. Bascur, J. Pat Kennedy

"The profitability of mining and metallurgical operations continues to lag behind that of other industries despite the technical advances that have occurred in recent years. A primary reason for poor performing in this economic sector is the lack of integration of mining and metallurgical information. The mine cut-off grade can be optimized if mining and metallurgical engineers have the data to optimize milling for the type of ore in hand.Integration of mine transactions, stockpile inventories, process flows and assays is the key to determining the economics for each blast strategy in a mining site. Real-time information from manufacturing assets greatly affects the profitability and flexibility of a company, but gross errors from faulty sensors, inaccurate instrument calibration, or incorrect process models may corrupt actionable information. New software tools can model the process, sift through available data to identify and eliminate gross errors, and use statistical data reconciliation to create materially balanced and consistent readings. The reconciled data is unified for use by both monitoring and decision making processes.Creating a real-time information environment where upgrade and change are allowed is becoming an accepted methodology to accelerate and simplify the integration of applications such as production monitoring, equipment performance management and yield and inventory management.This paper describes the data integration requirements in a mine, concentrator and port for unification of the redundant data. The capture of the mining events, stock pile management and the metallurgical information is the base requirements for a dynamic environment to reduce the overwhelming amount of information to unified set of information. Part of any decision support program should entail these results to continuously improve the measurement system to address the costs in mine and milling the ore."

Jan 1, 2003

By Leopoldo Gutierrez

Eight oil sand ores with the bitumen content ranging between 3.6 and 15 wt.% and the fines content (-44 micrometers size fraction) between 9 and 69 vol.% were subjected to the standard alkali extraction test used to measure the degree of oxidation of metallurgical coals. The results showed that there is a strong correlation between the absorbance of extracted solutions at a wavelength of 520 nm and the ratio of the fines content to the bitumen content. The latter factor is directly relevant to assessing the extractability of bitumen from oil sand ores. Bitumen extraction tests showed that the bitumen recovery decreased from 90 % to 30 % when the absorbance at 520 nm increased from 0.23 to 0.64. A comparison of the UV/visible spectra of solutions obtained from the alkali extraction tests with solutions of Aldrich Humic Acids suggest that low bitumen/high fines oil sand ores release substantial amounts of organic matter very similar, if not identical, to humic acids. In contrast, high-bitumen and low-fines ores do not release as much of the organic matter, and UV spectra of these leached substances are quite different from those of humic acids. Overall, the results show that chemical composition of bitumen in the tested ores varies greatly with ore type and oxidation, and that the alkali extraction test is a promising technique to quickly assess the extractability of bitumen from a given ore type.

Sep 1, 2012

By M. E. Holuszko

This paper reports the results of induction time measurements carried out on the products of film flotation of galena and sphalerite particles from three different size fractions (38~75µm; 75~150µm; 150~212µm). As expected, the tailings (sinking fraction) from film flotation at any particular surface tension, had always longer induction times than the concentrates (floating fraction), for both minerals. The difference between the induction times of film flotation concentrate and tailings could be as little as 2.5 ms and 5 ms, and as large as 6 ms and 10 ms. These differences can be related to the different hydrophobic characteristics of these fractions, as expressed by (?c) and composition of the particular film flotation product. In addition, the induction times of the larger particle size fraction were shown to be longer than for the corresponding smaller particle size fraction, even though the average ?c(degree of hydro-phobicity) of these fractions appears to be very similar. Desliming, Cu activation and collector addition to the sphalerite samples was shown to decrease the induction time values significantly.

Jan 1, 2014

By Teemu Väyrynen, Matti Vilkko, Antti Jaatinen, Pekka Itävuo

"This paper shows that smooth and accurate feed-hopper level control is essential for consistent cone crusher operation. The objective of the paper is to define the best practices for tight control of cone crusher feed-hopper level. The paper discusses the challenges involved in a delay-dominant level control problem (specifically, dead-time-induced performance and stability issues, mass flow disturbances, process and actuator non-linearity) and proposes five corresponding control structures. The performance of the proposed control structure candidates is evaluated in a simulation study and, finally, a full-scale experiment is conducted for the best-performing candidate. The results of this study emphasize the importance of control structure selection. While the most obvious control structures failed to deliver the desired performance, the best result was achieved by using control structures that eliminate the conveyor transport delay (dead-time) from the control loop. In practice, the control loop dead-time can be eliminated by either using an actuator (variable-speed feed conveyor) that is connected directly to the feed-hopper, or by redefining the process boundaries closer to the used actuator (regulate the circuit mass balance instead of feed-hopper level). The presented control structures provide means to achieve a consistent cone crusher performance and size reduction. This facilitates efforts to improve the plant’s performance and increases the plant’s overall stability."

Jan 1, 2014

By David Dreisinger

"The leaching of base and precious metal ores and concentrates continues to progress in both laboratory study and industrial application. These developments are being driven by the need to respond to difficult ores and concentrates that are not amenable to conventional treatment. In many cases alternatives are being developed to conventional treatment (e.g. Pyrometallurgy) for technical and economic reasons.In this paper, a brief general review of some new developments in leaching will be followed by a more detailed explanation of three process developments that have either been industrially applied or are expected to be applied in a short time frame. The three processes to be reviewed in detail are the Mt. Gordon Copper Process, the Anglo American Corporation/University of British Columbia Copper Process and the PLATSOL Process. These leaching processes operate at low (90°C), medium (150°C) and high (220°C) temperature and are successful in quickly and completely extracting metal values from ores and concentrates."

Jan 1, 2003

By K. Hori

In this study, the determination of optimal conditions for jig separation has been investigated with a TACUB jig separator. The TACUB jig, from which a Batac jig originated, is a useful gravity separator that is effective to separate crushed solid wastes as well as coarse ores. A mixture of crushed polyethylene (specific gravity 1.3) and polyvinyl chloride (specific gravity 1.5) was separated by a batch TACUB jig by varying the frequency (wavelength) and the amplitude (pulse stroke length). It was found that the sample particle layer in the separation chamber was fluidized without turbulence by the rising water pulse resulting in the separation. However, a too strong water pulse reduced the efficiency of the separation of the particles. The results indicate that the specific velocity of the rising water is necessary to fluidize the particle layer without turbulence to separate the particles. The expansion ratios of the thickness of the particle layer in rising flows were measured in a cylindrical column. The pressure losses by the particle layer were calculated from the expansion ratios and the velocity of the rising flows by Ergun?s equation. The curve of the pressure loss vs. the velocity of rising flow showed a maximum point corresponded to the point of fluidization. The velocity of a rising flow on the point of fluidization provided the optimal separation condition.

Jan 1, 2014

By David Dreisinger

"The leaching of base and precious metal ores and concentrates continues to progress in both laboratory study and industrial application. These developments are being driven by the need to respond to difficult ores and concentrates that are not amenable to conventional treatment. In many cases alternatives are being developed to conventional treatment (e.g. Pyrometallurgy) for technical and economic reasons.In this paper, a brief general review of some new developments in leaching will be followed by a more detailed explanation of three process developments that have either been industrially applied or are expected to be applied in a short time frame. The three processes to be reviewed in detail are the Mt. Gordon Copper Process, the Anglo American Corporation/University of British Columbia Copper Process and the PLATSOL Process. These leaching processes operate at low (90°C), medium (150°C) and high (220°C) temperature and are successful in quickly and completely extracting metal values from ores and concentrates.INTRODUCTIONThe process of leaching is widely used in hydrometallurgy to selectively recover a metal of interest from an ore or a concentrate. Leaching and by extension hydrometallurgy is well established in the recovery of copper (copper heap leach ? SX-EW), nickel (Moa Bay and Caron process), zinc (roast ? leach ? electrowin and zinc pressure leach), gold (cyanidation) and uranium (acid sulfate leach). Of course this success extends to many of the metals found in nature. Recently, the importance of hydrometallurgy appears to be increasing with hydrometallurgy viewed as an attractive alternative to both traditional mineral processing and conventional smelting/converting/refining. This increasing interest has led to intensive study and increasing application. Selected developments include:Copper ? the Mt. Gordon process and new concentrate processes such as INTEC, Activox, CESL, Dynatec, Total Pressure Oxidation, MIM Albion, BioCop, and the AAC/UBC Process.Nickel ? Voisey Bay process for hydrometallurgical treatment of Voisey Bay concentrate, HPAL processing of laterites at Murrin Murrin, Bulong and Cawse, atmospheric leaching of laterites, heap bioleaching of nickel sulfides by Titan Resources (Australia).Zinc ? establishment of zinc leach, solvent extraction and electrowinning technology for treatment of the Skorpion deposit in Namibia, new developments in atmospheric and pressure leaching, the Hydrozinc process.Gold ? development of a number of thiosulfate leaching processes for recovery of gold from refractory carbonaceous ores or concentrates."

Jan 1, 2003

By V. A. Ivanova

Modification of hydrophobic part of carboxylic collector molecule is an upcoming trend for producing new reagents and changing its flotation properties such as activity, selectivity, sensitivity to hardness salts that inevitably present in the pulp liquid phase in the processing of ores containing calcium minerals. A wide range of apatite collectors ? monoalkyl ethers and monoalkylamides of dicarboxylic acids ? succinic, o-phthalic and maleinic acids have been synthesized by the addition of aliphatic alcohols and amines with various hydrocarbon radical value (from ?11 to ?16) to anhydride of the corresponding acid. Using computer modeling based on ChemBio 3D program of specialized complex Chem?ffice the calculation was carried out of charge distribution on atoms, energy parameters of molecules for investigated compounds. Calculated values of absolute hardness (?=6.75 ? 12.36) and absolute electronegativity (?= 5.67 ? 8.90) of the reagents showed that monoderivatives of dicarboxylic acids refer to the ?hard? type of bases. The degree of a charge transfer during calcium compounds formation of considered collecting agents (?N=0.009 ? 0.143) has been computed. Dissociations, micelle formation in solutions of these reagents and its hydrophobic and collecting properties were investigated in respect to apatite. Dependence of bulk, surface and collector properties on collector molecule architecture (double bond or benzene ring and non-ionogenic functional group in the structure of hydrocarbon radical) has been established. It is shown that experimentally determined dissociation constants (??a=5.16 ? 5.60 for succinic acid derivatives and ??a=3.32-3.78 for maleinic and o-phthalic acid derivatives) perfectly correspond to acidic properties predicted by computer calculations. Compounds of monoalkylderivative dicarboxilic acid have been determined optimum in composition and structure. The results of apatite flotation from apatite-nepheline ores of the Khibiny deposit (the Kola Peninsula) are presented here and show benefits of selected reagents. Keywords: monoalkylderivatives, dicarboxylic acids, reagents, microflotation

Sep 1, 2012

By S. Vimalnath

The bioremediation capability of Pseudomonas aeruginosa cells was investigated for the biosorption of lead ions from aqueous solution. The various parameters such as pH, kinetics, biomass loading and concentration of lead affecting the biosorption process were studied. Complete bio removal of lead could be achieved for an initial concentration of 12.4 mg/L at pH 6.2, corresponding to typical industrial effluents. The biosorption isotherm followed Langmuirian behavior and the Gibbs free energy (?G) was determined to be-30.8 kJ/mole, indicative of chemisorption between the functional groups of the bacterial surface and lead. The biosorption kinetics adhered to a pseudo-second order model. The possible mechanisms of interaction of lead with the bacterial cells are discussed. A carbon paste electrode with a coating of biomass was developed for lead ion detection in aqueous solution using cyclic voltammetric technique. Concentrations of lead up to 5x10-5 M could be successfully detected using cyclic voltammetry, which could be improved to a detection limit of 1x10-8 M adopting differential pulse anodic stripping voltammetry (DPASV). Keywords: Pseudomonas aeruginosa, bioremediation, lead, voltammetry

Sep 1, 2012

By Fang Liu, Xin Tan, Zhong-ming Wang, Yan-bo Shang, Jie Zhao

"The flotation separation of sulphides bulk concentrate containing Cu, Zn, Mo and Bi, which was obtained by both table-flotation of gross sand of gravity separation of wolframite and bulk flotation of wolframite slimes using butyl xanthate and oil No. 2, etc., has been conducted by using the cyanide process in the tungsten concentrator. The process has problems of high reagents consumption (25 tonne of cyanide dosage per year) and mineral processing cost (800~1000 RMB reagents cost per tonne of by-product concentrates), high mutual containing loss in the by-product concentrates and serious environmental pollution caused by lots of cyanide-containing wastewater. In order to solve this problem, a new cyanide-free separation technology is studied, which is used to process this sulphides bulk concentrate with 8.68% Cu, 8.98% Zn, 0.26% Mo, 1.58% Bi and 40.12% S. The results of the closed circuit test show that Cu, Zn, Mo and Bi can effectively be separated from this sulphide minerals concentrate by using the reasonable flotation-gravity flowsheet, high-efficiency collectors and regulators simultaneously. The metallurgical recovery and concentrate grade are as follows: molybdenum recovery is 94.63% with 50.62% Mo content; copper recovery is 85.18% with 29.29% Cu content; zinc recovery is 75.92% with 46.49% Zn content; total Bi recovery is 65.08% with 16.86% Bi content. The new technology is an alternative to the cyanide process due to its low cost for reagents, satisfying separation results and economic profits, and solves the problem of environmental pollution caused by the use of large quantities of cyanide. Some important parameters in separating the Cu-Zn-Mo-Bi sulphides concentrate are also introduced in this paper. This study provides pretty good technical support for separating the polymetallic sulphide ores containing Cu, Zn, Mo and Bi by cyanide-free technique."

Jan 1, 2014

The present work aimed to verify the possibility of using froth flotation to separate the constitu-ent minerals of an alaskite rock waste having as the main minerals quartz and feldspar. Three stages of tests have been carried through. In the first stage was used an amphoteric collector for flotation, diaminedioleate, at pH 2 and, after analyzing the final products, a very poor selectivity was ob-served. During the second stage of tests, different collectors that are normally used for feldspar flo-tation as amines, sulfonates and soybean oil were employed. Once more, it was not possible to reach reasonably selective results. In the third stage, a salt of etheramine was used for collecting the feldspar and hydrofluoric acid was utilized for controlling the pH. A simulation of three flotation steps (rougher, cleaner and recleaner) permitted to attain a good selectivity in the flotation process. A concentrate with a silica content of 96.6% was obtained. The low concentrate content of alkalis totalizing 0.52% and a feldspar recovery of 96.5% to the tailings, represented by the high content of Na, K, and Al2O3 in the tailings, demonstrated that the concentrate was made up mostly of quartz.

Jan 1, 2014

By Andrew T. McBride, Malcolm S. Powell, Indresan Govender

"Current empirical Semi Autogneous Grinding (SAG) mill models contain assumptions concerning the amount of energy available for particle breakage, how this energy is distributed in the mill media and the rate at which the energy is transferred. Despite these assumptions the JK SAG model is highly functional with a proven track record. DEM provides a numerical framework to greatly improve on these assumptions that were necessary due to a lack of available input data.This paper identifies key outputs of the Discrete Element Method (DEM), such as energy spectra and impact probability distribution. It describes how they can be incorporated into current mill models utilising practical rock breakage data. The rate at which energy is transferred is shown to be dependent on particle position and mill rotational speed and not once per cycle as previously assumed. Based upon this an improved energy transfer methodology is presented. The fundamental outputs of the DEM are validated against experimental three-dimensional particle tracking data, so as to establish whether the DEM produces correct energy transfer predictions on the inter-particle level, which is crucial to this work."

Jan 1, 2003

By T. Mütze

The progress in comminution is often described by the specific surface area and the energy utilization or the brakeage ratio and breakage function. The principal mechanisms of size reduction are therefore, well known. All four parameters share a common disadvantage: They are limited in describing the behavior of a feed material with fine particles and a wide particle size distribution. An alternative is to describe the progress in comminution with ? The particle size distributions Q(x) before and after the stress or ? The particle concentration ratio pcr(x), which combines these two states. In the case of a self-similar fracture behavior, (in short: self-similarity) the progress in comminution can be simplistically described by the relationship between a reference particle size and the stress intensity. Self-similarity means self-similar breakage functions of geometrically similar particles of the same strength, a certain stress situation and stresses up to the breakage point. Self-similar breakage functions show the same curve at different stress intensities when the fragment size x is normalized with a reference particle size xNorm. This behavior was demonstrated for single particle comminution repeatedly and unequivocally. In the field of particle bed comminution, these results differ in literature. Therefore, the self-similarity in particle bed comminution was systematically investigated at the Institute of Mechanical Process Engineering and Mineral Processing of the TU Bergakademie Freiberg as part of a research project. Limestone, quartz, silicon carbide and glass beads, were examined with a hydraulic press. The particle sizes covered monodisperse fractions in the range of 1-1000 µm, bimodal mixtures of these fractions and polydisperse fractions. The results obviously show that there is no self-similar fracture behavior in the case of glass beads, quartz and silicon carbide. Statements on the self-similarity of limestone are much more difficult: Only some of the investigated limestone fractions show a similar clear, non-self-similar behavior. Self-similar curves appear particularly for fine monodisperse fractions as well as bimodal mixtures, which stressed with pressures above 200 MPa. Considering the measurement accuracy of particle size analysis the coincidence of the curves can be explained by the fact that progress in comminution almost ends above 200 MPa. At this point, a hydrostatic stress state is reached in the particle bed which is known from the literature. This stress state inhibits further fractures. Overall, it has been verified for the investigated materials that there?s no self-similar fracture behavior in particle bed comminution. One reason for the diverse opinions in literature is that there are three types of particles after the comminution in the particle bed: ? Particles which are stressed below their breaking point, ? Particles which are stressed right up to the break point, and ? Particles which are stressed beyond their breaking point.

Sep 1, 2012

By T. Fujita

A high-grade fluorite ore is converted into hydrogen fluoride to produce many kinds of materials containing fluorine. Recently, it is becoming necessary to use low-grade fluorite ore due to the depletion of high grade ore. The low-grade fluorites usually have impurities such as SiO2, P, CaCO3 and arsenic. The most impurities such as SiO2, CaCO3 and P can be removed by using flotation method. However, the removal of arsenic is difficult, and the arsenic contamination decreases the hydrogen fluoride production percentage. The novel technologies for processing low-grade fluorite ore are urgently needed, in order to lower the arsenic concentration to less than 100 mg/kg. In this study, the removal of arsenic from low-grade fluorite ore has been investigated by means of an autogenous grinding using tower mill in sulfuric acid aqueous solution and 0.3 mm zirconia balls in water. The nano grinding in water can prevent the dissolution of 0.3 mm size zirconia balls as grinding media by sulfuric acid solution. Experimental results showed that the arsenic concentration was reduced from 260 mg/kg to 90 mg/kg and CaF2 recovery reached 90% by this process.

Sep 1, 2012

By A. M. Muhamedilova, S. M. Narbekova, L. V. Semushkina, D. K. Turysbekov, N. K. Tussupbayev

The research and development of new, more selective collectors in order to improve flotation efficiency represent one of the main priorities in the development of innovative technologies pertaining to flotation separation of various substances and minerals. The use of collectors’ mixtures is considered as the universal instrument for ensuring necessary proportion of chemically and physically sorbed collecting reagents in every individual case. Currently hard-dressed, refractory ores and man-made raw materials, which are characterized by low content of valuable components, fine dissemination of mineral assemblages and similar technological properties of constituent minerals, are widely involved in the recycling processes. The possibility of processing tailings, which are left after flotation beneficiation, has been considered in the case study of tailings of the Zhezkazgan beneficiation plant and the Tishinsk copper ore deposit with utilization of the modified multifunctional flotation reagents. Modified poly-functional collector is the mixture of composite Aerofloat, TC-1000 and butyl xanthate. Reactants ratio is 1:1:3. The advantage of the suggested flotation reagents is that they are composed of two polar groups and have a long hydrocarbon radical. This structure, being in the water during flotation process, plays a dual role: first, as a collector adsorbing on the mineral surface it produces metal complexes with polar groups in the form of bridges; second, apolar radicals flocculate valuable slimed components, thereby intensifying flotation process. It has been shown that flotation of Zhezkazgan tailings with utilization of the lesser modified reagent amount compared to butyl xanthate has enabled to produce crude copper concentrate with 13.0 % copper grade and 80.22 %recovery. Compared to the baseline technology, copper content of crude concentrate has been increased by 5.1 % and the recovery by 31.4 %. It is shown that tailings flotation of the Tishinsky field by applying modified collector allows for increase of the of useful components extraction in a collective concentrate with: copper 9.63 %, lead for 8.41%, zinc 9.2 %, iron 2.73 %, gold 3.57 %.

Jan 1, 2018

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 Ljubisa Obradovic, Baisui Han, Batnasan Altansukh, Zoran Stevanovic, Atsushi Shibayama, Jonovic Radojka, Daizo Ishiyama, Kazutoshi Hag, Radmila Markovic, Ljiljana Avramovic

This paper discussed a combined froth flotation and high pressure leaching (HPL) process to recover copper from mine tailings. At first, froth flotation were carried out using the mine tailings sample under various conditions in the presence of different pH (3.5-10) and sulfurizing reagent value (0-1000 g/t), respectively. As a result, optimum condition (sulfurizing reagent of 1000 g/t, pH of 10, PAX (collector) of 100 g/t and MIBC (frother) of 200 g/t) was found for froth flotation of copper. The effects of sulphuric acid concentration, leaching temperature, total pressure (steam pressure plus oxygen pressure) on high pressure leaching (HPL) of mine tailing were investigated using sulphuric acid solution in the presence of oxygen. The best conditions for HPL were obtained to be sulphuric acid concentration: 0 mol/L (water), leaching temperature: 170 ?, total pressure: 2 MPa, leaching time: 1 hr and pulp density: 100 g/L. The leaching rate of copper reached nearly 99 % and the concentration of copper in pregnant leach solution (PLS) was 0.24 g/L. Finally, copper in the mine tailing was recovered using froth flotation followed by HPL. As a result of a combined froth flotation and HPL, the vast majority of copper (99 %) from the mine tailings was extracted.

Jan 1, 2014

"This research represents a shift away from empirical models that lock the industry into 50-year old inefficiencies with little response to operating variability. The mechanistic and intrinsically dynamic mill model under development steps up to a new paradigm using the latest computing capabilities and physical understanding of breakage and transport to transform predictive capabilities for design, optimisation and on-line control with variable feed. The milling process is broken down into discrete sub-processes, each of which can be modelled as an object in the whole model and in the model code. These objects can be upgraded or exchanged without having to rewrite or restructure the remainder of the code. Sub-processes include: feed into mill; transport along mill; presentation to impacting events; range of impacting forces; probability of being impacted in different zones in the mill as a function of particle size and density; suspension in slurry; and discharge out of the mill. The unit and processes surrounding the mill (feed and recycle conveyors, slurry pump and pipe, cyclone and recycle crusher) have also been modelled, in order to incorporate the effect of recirculating load coming from a cyclone or a recycle pebble crusher, respectively for ball mills or SAG mills. Each unit is modelled dynamically and PID controllers have been added to control pumping flowrate from sump and water addition for cyclone feed dilution. The paper demonstrates the predictive capability of a dynamic, mechanistic model and is used to test the sensitivity to the sub-processes, comparing different formulations and highlighting the aspects that require further development. Validation on pilot tests and application to industrial data is presented. This approach is currently undergoing industrial trial on sites, for use in on-line model-informed process control. Considerable further development is required to incorporate the full mechanistic structure planned for this model."

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 M. Muravyov, T. Kondrat’eva, A. Bulaev

Metallurgical treatments of sulfide ores containing copper and zinc are characterized by significant losses of base metals, particularly formation of the flotation tailings and slags during the dressing and pyrometallurgical treatment respectively. In addition, SO2 gas obtained during roasting and converting may be as raw material for sulfuric acid production. A treatment of the industrial metallurgical wastes has been investigated. Two samples of old pyrite tailings from two concentrators that contained 0.36% and 0.26% of copper and 0.23% and 0.22% of zinc were leached with 10% sulfuric acid in the column. Recovery of copper reached 47% and 38% while recovery of zinc was 47% and 41% from the first and second samples, respectively. The pregnant leach solutions contained 15.9 g/l and 10.5 g/l of ferric iron. Ferric iron is the strong oxidant and ferric containing pregnant leach solutions can be used for ferric leaching of different types of raw materials containing sulfide minerals. Therefore, ferric leaching of copper converter slag flotation tailings contained 0.53% of copper and 2.77% of zinc with the first pregnant leach solution was conducted. The effect of various experimental parameters on the leaching dynamics of copper, zinc, and iron under batch conditions was investigated. Under the best conditions (temperature 70oC, pulp density 30%) the recovery of copper and zinc reached 80% and 42%, respectively. Thus, it has been shown that acid leaching of base metals from old pyrite flotation tailings with using of the pregnant leach solution for the ferric leaching of copper converter slag flotation tailings is a prospective technique for the complex treatment of mining and metallurgical wastes. Investigated processes could be introduced into the technological flow-sheet of typical pyrometallurgical plants.

Jan 1, 2014