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By Kwan Ho Kim

The beneficiation study of low quality pyrophyllite is conducted to enhance the value of it by selective grinding. In mining stage, the main gangue mineral is quartz, and the content of quartz in ore has an adverse effect on the quality of pyrophyllite. Using the huge difference in hardness between quartz and pyrophyllite, the selective grinding is accomplished using stirred ball mill. As a result, a finer pyrophyllite particle can be easily separated from coarser quartz particle by simple size classification, and the content of Al2O3 of fine particle smaller than 45um increased largely. It means that the pyrophyllite particle is ground selectively compared to the quartz particle, and the quality of pyrophyllite is enhanced.

Sep 1, 2012

By Renato S. Costa, Afonso H. Martins, Flávia D. Mendes

"This paper presents some important aspects regarding the ion exchange treatment of an Ni and Co sulphate acidic liquor using chelating resins. Chelating resins possessing iminodiacetic or bis-picolylamine functional groups were compared in terms of nickel and cobalt recovery. The experimental resin with bispicolylamine functionalities (Dowex M4195) was evaluated with respect to Ni and Co uptake, and compared with Rohm &Haas commercial chelating iminodiacetate acid resin. The Rohm & Haas chelating resin, Amberlite IRC 748, with its weakly acidic groups, did not work in acidic solution but exhibited good results at pH 4 and above. The resin that efficiently removed metals from high acidic solutions was the bis-picolylamine resin. Maximum nickel uptake values ranged between 85 g and 112 g Ni per Kg of resin.The experimental part dealt with the working conditions, resin characteristics and the influence upon the resin maximum exchange capacity of the following factors: nickel concentration, temperature, pH and resin-to- solution ratio. Based on the experimental data obtained, it has been proposed a innovative technological treatment."

Jan 1, 2003

By M. Tang

The phosphate ore sample was taken from the iron tailings after recovering most of magnetite by magnetic separation in Longlin, Yunnan Province of China. Batch flotation tests had been conducted to upgrade the phosphate concentrate by conventional fatty acids reagents under 70% -75 µm of the particle size; however, the unsatisfied results (P2O5 grade of 27.84% and recovery of 49.25%) were obtained. Also there are a large amount of slimes trapped in the concentrate and high-dosages consumption of reagents, for example, more than15 kg/t soda ash and 2 kg/t sodium silicate at only one-staged roughing. Based on the analysis of X-ray diffraction (XRD) for the sample, most of gangues are clay, quartz, and chlorite, which may easy to over-grind and deteriorate the flotation process either on reagents consumption or slurry fluidity or viscosity. A hydro-cyclone had been introduced to pre-concentrate the phosphate ore by scrubbing the slime before flotation, which can result obviously in reducing the dosages of soda ash from 15 Kg/t to 4 Kg/t, and raising the grade of P2O5 in the concentrate from 27.84% to 36.13% at the expense of about 4% recovery of P2O5. They also substantially reduced the time of sedimentation of concentrate after flotation from ~10 to ~1 min. In this paper, the effects on the recovery of P2O5 by the different dosages of flotation reagents with or without de-sliming were studied, with the objective of determining the different effects on the functions of flotation reagents by slime during flotation. Keywords: de-sliming, phosphate, soda ash, flotation

Sep 1, 2012

By T. J. Chen

Stone coal containing vanadium is an important vanadium resource in China. Roasting and oxidation of vanadium is the foundation for extracting vanadium from stone coal. This article takes stone coal vanadium ore in Tongshan of Hubei Province as research target to conduct oxidation roasting test on it by using a self-developed low-sodium compound additive and a new optimized technology. Firstly, use potentiometric titration, X diffraction, energy spectrum and electron probe to study valence change, occurrence and phase transition of vanadium during oxidation roasting process. On this basis, primary work is done on oxidation kinetics of vanadium by exploring the steps that control reaction rate during vanadium oxidation process and determining the related dynamic parameter ? apparent activation energy. The study shows that occurrence of vanadium in stone coal of Tongshan is mainly in illite, and that the result of phase transition in roasting process is disappearance of illite containing vanadium, formation of soluble vanadate and potassium feldspar, albite. It further demonstrates that oxidation process of vanadium is step by step (V(?)? V(?)? V(?)), and its oxidation reaction is controlled by diffusion kinetics whose dynamic apparent activation energy is E1=81.19kJ.mol-1.

Jan 1, 2014

By Yuexin Han, Zehong Wang, Fujia Yu, Wanzhong Yin, Xinchao Wei

Bauxite is the main raw material in alumina and refractory industries. China has plentiful bauxite resources, most of which belong to the diaspore type bauxite with characteristics of high aluminum content, high silicon content and low ratio of alumina and silica (A/S). The resources with A/S 4-7 account for more than 60% of the total resource reserves of bauxite. Therefore improving the A/S through bauxite desilication is the key task of bauxite concentration in China. Normally the grinding fineness of 80-90% - 0.074mm is required in the bauxite flotation process. Thus fine grinding of bauxite ores is necessary, which leads to the high energy consumption. In the meanwhile, bauxite ores are easy to produce slime during grinding processes. The large amount of slime produced in fine grinding greatly worsens the process environment of bauxite flotation, affects the separation performance and results in the loss of metal. Also, fine grinding makes the flotation concentrate difficult to dewater, while the water content in the flotation concentrate must be removed by distillation in the subsequent alumina dissolution process, causing the increase of energy consumption and cost in the production of alumina. In this study, the selective grinding behaviors were examined with Henan Bauxite as feed. Separation of alumina and silica at a coarser grinding fineness was achieved and new route was explored to enhance the desilication in bauxite concentration to improve the A/S of bauxite concentrate.

Jan 1, 2003

By B. Friedrich, A. Weyhe, H. Heegn

"Nickel-metal hydride batteries (Ni-MH) are storers of electrochemical energy, which have a higher specific storage capacity than lead or nickel-cadmium batteries. The demand for Nickel-metal hydride batteries is increasing rapidly since their market launch in the early 1990’s. Today there is no suitable and sustainable recycling process to recover nickel, cobalt and rare-earth metals. The discarded batteries are used today in the steel industry as alloy material because they contain nickel. Cobalt and rare-earth metals (RE) are lost; they are non-recycleable.In a German governmental funded research project, IME Aachen, ACCUREC Mühlheim and UVR-FIA Freiberg are cooperating in processing as well as in creating a feasibility study. The target of this project is the development of a new recycling process for metal recovery from Ni-MH-batteries. The proposed process described in this paper consists of a combination of mechanical, pyrometallurgical and hydrometallurgical processing steps. This process is capable of treating all types of Ni-MH-batteries. After comminution steel and organics are separated. The separated Ni-MH is smelted in an electric arc furnace. The products are a nickel-cobalt alloy and a slag phase enriched with rare-earth oxides for further treatment to ‘mischmetal’. Both the Nickel-Cobalt alloy and the ‘mischmetal’ will be directly used in battery production."

Jan 1, 2003

By Zhangm Zeqiang, Manman Lu, Hanquan Zhang, Hong Yu, Jintao Fu

"Pelletizing is an important technique in the ironmaking industry. Artificial and natural magnetites are materials that are widely utilized in the iron ore pelletizing process. In this work, the pelletizing characteristics of these two types of magnetite have been investigated in detail. The obtained results shown that in contrast to natural magnetite, the artificial magnetite concentrate exhibits stronger hydrophilicity, lower electronegativity, larger specific surface area, and rougher surface. In addition, the green pellets produced from the artificial magnetite concentrate are characterized by a higher compressive strength as compared to that of the pellets obtained from the natural magnetite concentrate. However, the shock temperature of the artificial magnetite pellets around 255 C is significantly lower than the threshold specified by the industry. The balling characteristics of the material obtained by mixing 20% of the artificial magnetite concentrate with 80% of the natural magnetite concentrate are considerably improved with respect to those of the individual components.INTRODUCTION Pelletization is an essential process of the ironmaking industry in China. Since the pellets produced from iron ore exhibit high mechanical strength, good particle granularity, and uniform shapes, pelletizing high-grade iron ores with good metallurgical reducibility can lower the coke ratio, improve their technico-economic index, and reduce the cost of processing pig iron in blast furnaces[1, 2]. Presently, high-grade magnetite is a material utilized for pelletizing various iron ores across the globe. However, its natural deposits have been depleting rapidly in recent years; as a result[3], China’s dependence on the foreign high-grade iron ores exceeded 70% in 2009 and reached the level of 87% in 2016. Hence, possible methods for the efficient cultivation of limonite, siderite, hematite, and other refractory minerals that correspond to low-grade, finely sized, inhomogeneous, and scattered iron ores have attracted significant attention [4, 5]. In particular, magnetization reduction roasting and magnetic separation techniques, which are widely utilized for obtaining high-grade artificial magnetite, represent effective ways of processing iron ores that can alleviate the scarcity of natural magnetite resources [6, 7]. The artificial magnetite produced by magnetization reduction roasting exhibits different characteristics as compared with those of natural magnetite (including the degree of hydrophilicity, surface potential, specific surface area, and other surface physicochemical properties[8-11], which significantly affect its pelletizing behavior. In this work, the surface characteristics of artificial and natural magnetites are investigated in detail, and their effect on their pelletizing properties (such as green ball strength, heat stability, and pelletization rate) are examined."

Jan 1, 2018

There is a strong demand for nickel metal due to quick development of stainless steel and new electrical materials, most of which is extracted from sulfide resources, resulting in a serious depletion of sulfide resources. Therefore, more attentions have been paying to extracting nickel from nickel laterite, which accounts for some 50% of total nickel metal production. In this paper prereducing?magnetic separation?reduction smelting process is developed to manufacture ferronickel rom two types of nickel laterite DN and GN, assaying 1.42% 1.83% Ni and 49.09% 26.08%Fetotal, respectively. Mineralogy of two types of nickel laterite was determined and optimization of process parameters was conducted to manufacture ferronickel. Prereduction?magnetic concentration process is used to upgrade low grade nickel laterite firstly, two kinds of Ni-Fe concentrates being prepared of DN assaying 2.26% Ni and 69.45% Fetotal and GN containing 2.76% Ni and 38.00% Fetotal. Finally, two types of ferronickel were produced by reduction smelting of prereduced concentrates DN and GN, DN and GN ferronickel contains 2.97% Ni and 6.58%Ni, 89.25%Fetotal and 89.95%Fetotal, respectively. The total recoveries of Ni and Fe of the two ferronickel are beyond 90% and 80%, respectively. There is significant difference in grade of magnetic concentrates and ferronickel between DN and GN laterite due to their different mineralogy, the former belongs to limonitic laterite and the latter saponite one. There are some advantages for this process to manufacture ferronickel from nickel laterite, including effectively upgrading low grade nickel laterite by prereducing?magnetic separation technique, higher throughput and lower energy available for reduction smelting section due to some 40% gangue being rejected in pre-upgrading section, and much less metallurgical coke consumption by using non-coking coal as reductant for prereducing?magnetic separation?smelting process.

Jan 1, 2014

By F. Q. Cheng

Despite the successful industrial practice to recovery KCl by flotation, the adsorption state of collectors at KCl salt surfaces is still not fully understood. In this paper, the captive bubble contact angle measurements at KCl and NaCl crystal surfaces in their saturated solutions are reported. The influence of different collectors and their concentration are considered. The results show that both cationic and anionic collectors produce a hydrophobic state at the structure breaking KCl salt sur-face, with finite contact angle values of between 30o and 40o. In contrast, the contact angle at the structure making NaCl salt surface is zero at all collector concentrations, suggesting that no collec-tor adsorption occurs, a supposition that is supported by results from molecular dynamics simulation (MDS). Further, it appears that the presence of surface defects such as edges and corners promote the adsorption of collectors at the KCl surface, and that the flotation is achieved by bubble attachment at the edges/corners of KCl particles with the formation of aeroflocs.

Jan 1, 2014

By I. N. Gridasov, V. V. Khromov, R. I. Ismagilov

"Over 50 mln.tonne is the average annual output of oxidized ferruginous quartzites typically containing Fe38-42% mined in Mikhailovskoye ore field. The most promising and cost-effective way to expand concentrate production maintaining current output of magnetite is processing of oxidized ferruginous quartzites (hereinafter referred to as OFQ) mined as a by-product in Mikhailovsky open pit mine. However lack of proven and efficient concentration and agglomeration process applicable to OFQ and insufficient data for feasibility evaluation of OFQ processing encumbered full-scale addressing of this challenge. Based on outcomes of multiple various studies a process of OFQ flotation was designed by MC Metalloinvest LLC and PJSC Mikhailovsky GOK engineers. Comparative lab-scale testwork have proven performance and production advantages of flotation against magnetic separation feat. flotation and combined concentration method. Lab-scale flotation enabled production of concentrate with average Fe66.6% and SiO22.06% grade. Geologic and production contouring of OFQ deposited in Mikhailovskoye ore field has been carried out to collect necessary data for feasibility study incl. cost and profit estimation. As a result processing and production properties of over 3,500 samples have been analyzed which is characteristic of every direction and level of prospective ore mining within Mikhailovskoye ore field up to year 2032. Following work has been done based on geologic and production contouring of OFQ: – natural typification of ores and production (processing) grades of OFQ, determination of average mineral composition; – correlation analysis of interrelation between OFQ mineral composition and processing features thereof for overall bulk of samples as well as for individual data blocks related to various directions of open pit mine; – OFQ classification with account of defined mineral composition and processing features. Total Fe weight content in chamber product of flotation (known as concentrating ability in flotation) was applied as a major differentiating factor for processing grade classification of OFQ. Three processing grades of oxidized ferruginous quartzites were established as a result of flotation tests run to determine concentrating ability, i.e. – hard concentrated OFQ (TO) – below Fe65%; – mean concentrated OFQ (SO) – Fe65-67%; – easy concentrated OFQ (LO) – over Fe67%. Outcome of this work provided initial data for feasibility study and cost-profit evaluation of medium-term industrial-scale processing of OFQ deposited in Mikhailovskoye ore field."

Jan 1, 2018

By Brabcova Z.

This contribution deals with bubble adhesion on particle surface which consists of three steps ? the liquid film thinning, the film rupture and expansion of the three phase contact (TPC). Our attention is devoted to the third step ? to the description of the TPC expansion. Three-phase contact line expansion can be theoretically described using hydrodynamic and molecular-kinetic models. Both of these models were originally developed for the interaction of the bubble with horizontal plane in pure water. Our experiments deal mainly with the interaction of the bubble with the inclined plane in the solution of surface active agents. It was proved experimentally that molecular-kinetic model corresponds also to these conditions and this model was used for the description of the TPC expansion. The model is based on the theoretical description of the bubble contact angle on the three-phase interface. These contact angles change dramatically from 180o to equilibium (Young) contact angle close to 90o. Modificated ADSA method is used for the calculation of the contact angle. This method utilizes the Laplace equation of the capillarity; the bubble profile and the contact angle are evaluated using the set of experimental points around the edge of the bubble. The comparison of the experimental and calculated bubble profile shows a good agreement. The aim of the project is to describe the process of the TPC expansion during the adhesion of the bubble with the diameter up to 1 mm. Inclined planes were used instead of an experimental solid particle. Our experiments were provided in the solution of surface active compounds. The process of the adhesion was recorded using high-speed digital camera and images were evaluated using the image analysis software NIS-Elements. Calculations were performed using the MATLAB software. Keywords: bubble-particle interaction, adhesion, three-phase contact, contact angle

Sep 1, 2012

By P. Somasundaran

Treatment of mineral surfaces with appropriate surfactants plays an important role in mineral processing operations such as flotation, flocculation and dewatering. Recently biosurfactants, in particular, have received a considerable amount of attention because of their unique surface active properties and biodegradability. In this work we examined the performance of biosurfactants, sugar based alkyl glycosides and sophorolipid esters as reagents to control the hydrophobicity of minerals with selectivity of adsorption on mineral surfaces for flotation applications. It was discovered that n-dodecyl-ß-D-maltoside adsorbs on alumina, titania and hematite but, interestingly, not on silica. The hydrophobicity obtained is governed both by the surface coverage as well as the nanostructure of the adsorbed layer in terms of orientation of the adsorbed species. Surprisingly, even though the above surfactants are non-ionic, their adsorption was pH-dependent. We have correlated this pH dependence to the type of species on the mineral surface. Also it is shown that mixing of these surfactants with traditional ones can help reduce the carbon footprint due to synergy between the reagents and help selectivity due to antagonism. The experimental results were analyzed to get information on optimal pH and dosage conditions, for mineral surface modification. The study provides guidance for mineral treatments using biosurfactants and the potential use of these next generation reagents in mineral processing.

Jan 1, 2014

By G. Granata, C. Tokoro, T. Kato

The rare earth elements (REE) are composed of 17 elements that are 15 elements of lanthanide added scandium and yttrium. REE are divided into light rare earth elements (LREE) and heavy rare earth elements (HREE). Although the supply source of LREE is distributed around the world, the supply sources are unevenly distributed. Thus, the development of a new HREE supply source is required. In this study, we focused on the weathered residual rare earth ore as a new HREE supply source. Since so far this weathered residual rare earth ore could not be treated neither by flotation nor by wet high intensity magnetic separation, it was not considered as HREE resource before. In this study, we investigated the leaching of HREE from the weathered residual rare earth ore and elucidated the effectiveness of planetary milling with sodium hydroxide as a method to enhance their recovery. For this purpose, the weathered residual rare earth ore was first grinded by planetary mill in the presence of sodium hydroxide and then leached by sulfuric acid. The influence of planetary milling on HREE recovery was investigated by assisting the leaching experiments with X-ray absorption fine structure (XAFS) in cerium and yttrium K-edge. Since yttrium was the most contained HREE in the weathered residual rare earth ore used in this study, we focused on yttrium in XAFS analysis. Results clearly showed that the recovery of HREE increased by planetary milling with sodium hydroxide. XAFS analysis revealed that a part of the yttrium in the weathered residual rare earth ore was changed to yttrium hydroxide by planetary milling with sodium hydroxide. It is supposed that all HREE were affected like yttrium due to a similar behavior observed in leaching.

Jan 1, 2018

By I. I. Maximov

The paper describes the results of studies performed with a view to develop an improved technology for processing high-grade massive and cupriferous ores of the Talnakh deposit, the main valuable components being nickel, copper and PGM. The studies? main task was production of nickel concentrate with nickel content of approx. 15%, nickel recovery being as high as possible. The studies were performed on two ore samples. One sample was a mix containing high-grade massive (78%) and cupriferous (22%) ores with nickel content of 1.93% and copper content of 3.6%; the other sample was a mix of high-grade ores with nickel content of 2.25% and copper content of 3.72%. Main ore minerals were copper sulfides ? chalcopyrite and cubanite, their total content being 10.5% ~ 11%, pentlandite (5.2% ~ 6.1%) and pyrrhotite (36.7% ~ 42.9%). Influence of grinding media on pentlandite and pyrrhotite separation results, achieved through combined use of triethylenetetramine (TETA) and sodium sulfite (SS), was also investigated. It is shown, that combined application of TETA/SS in the ratio of 1:2, permits to grind products in metal mill (mild steel) with metal balls (mild steel), achieving results that are similar to those achieved by means of grinding in inert grinding media with TETA/SS ratio of 1:1. Application of the developed technology provided for production of high-grade nickel concentrate with nickel content of 14.7% ~ 15.6%, nickel recovery being 76 % ~ 77%. Earlier experiments performed on the above mentioned ore mix permitted to produce nickel concentrate with nickel content of 10%, nickel recovery being 75.9%. Consequently, nickel content was increased by 4.7% ~ 5.6%, and a higher nickel recovery was achieved. The paper also describes metallurgical results related to nickel, copper and PGM with regard to all processing products.

Jan 1, 2014

By E. V. Leont'eva, V. R. Vafin, A. G. Kladova, N. L. Medyanik, A. P. Ponomarev

"The thermochemical technology for recovery gold, silver from mature flotation tailings of pyrite ores by two-stage sintering with chlorine-ammonium reagents and leaching of bakes with water is developed. The economic effect of the technology implementation is calculated. KEYWORDS Gold and silver recovery, mature flotation tailings, pyrite ores, chlorine-ammonium reagents, leaching INTRODUCTION The relevance of processing the technogenic reserves of ore mining and concentration wastes accumulated over the long operation periods of mineral deposits is beyond doubt. Hundreds of tons of precious and non-ferrous metals that were not recovered during the primary processing are concentrated in the accumulated wastes. For example, tailing storage facilities (TSF) at the mineral processing plants in the Southern Urals region of Russia hold more than one hundred tons of gold and thousands of tons of silver in the mature flotation tailings (MFT) of copper pyrite ores. Secondary processing of technogenic materials is facilitated by the fact that they are preprocessed — ground and compactly deposited on the surface, but complicated by the low (compared to ores) grade, uneven distribution of the valuable minerals, altered and unstable material composition of the mineral feed. This leads to low recovery rates of valuable metals by conventional physicochemical processing methods. It is necessary to develop innovative methods of deep integrated processing of industrial wastes, based on the study of the material composition of specific technogenic mineral resources and based on ensuring the environmental safety of the resulting secondary waste. MATERIALS AND METHODS The object of this study are the MFT of Uchaly Concentrator in the Republic of Bashkortostan, Russia, which processes copper pyrite and copper-zinc ores. According to the data of particle size, chemical, X-ray phase, and optical microscopic analyzes, samples of the MFT are characterized by considerable particle fineness (the fraction of the size class -41 µm is 89-90%), low grade of gold (1.7-2.0 g/t) and silver (18.0-19.5 g/t), comparable grades of iron (23.0-26.8%) and sulfur (28.1-28.7), but different grades of copper (0.12 - 0.73%) and zinc (0.34-1.26%). The most common mineral in the samples is pyrite (50 - 56%), found in intergrowth with grains of other sulfides (0.1-4%) - sphalerite, tennantite, chalcopyrite, covellite. Quartz and aluminosilicates are the dominant rock minerals (21-36%). Based on the results of the phase analysis, it was established that approximately 70% of the gold in the samples is found in a form that is resistant to cyanidation — it is locked in sulfides (52-56%) and quartz and coated by films. Along with sulfides and rock minerals, common gold and silver minerals (chalcogenides, intermetallides, native gold) in the form of submicro- and nano-sized precipitates are also associated with intergrowth of a complex structure. These features of the material composition allow classifying the MFT of the pyrite ores as a mature feed material and emphasize the need for chemical non-cyanide methods to recover gold and silver from the mature minerals and associations they are found in."

Jan 1, 2018

By Weiran Zuo, Narayan Krishnan, Frédéric von der Weid, Emmy Manlapig, Fengnian Shi, Klaas van der Wielen

Laboratory study has identified a new application of high voltage electrical pulse technology for pre-weakening ores. In recent years, the Julius Kruttschnitt Mineral Research Centre (JKMRC), Newcrest Mining and SELFRAG AG have conducted joint research in validation of pre-weakening of SAG mill feed through the pilot scale tests and comminution circuit simulations. Ten tons of SAG mill feed with a top particle size 150 mm were tested with two pilot scale SELFRAG machines installed in Switzerland. A simulation study using JKSimMet software was carried out to find where the high voltage pulses pre-weakening technique can be best applied in a gold-copper ore comminution circuit, based on the data of the pilot scale SELFRAG tests. A novel comminution circuit was designed, which incorporated SELFRAG to pre-condition part of SAG mill feed (9.5 to 150 mm) and to treat the circulating SAG mill pebbles. The high voltage pulse technology effectively reduced the amount of ‘critical size’ particles in the SAG mill and pre-weakened particle strength for grinding. Attributing to the nature of bi-modal size distribution and the significantly reduced F80, the simulations showed that the SAG mill had spare capacity to process part of hydrocyclone underflow from the secondary ball mill grinding circuit. The simulations indicated that the novel comminution circuit had the potential to remove two MP1000 pebble crushers and one 10 MW ball mill from the existing 2000 t/h grinding circuit. A 5 kWh/t energy reduction by adopting the novel comminution circuit in a gold-copper operation may be realized. This would result in substantial savings in operation costs.

Jan 1, 2014

By D. R. Nagaraj

The traditional (popular) approach to reagent development and optimization, which has become entrenched in both research and practice for many decades, is highly reductionistic, incremental and costly, does not produce robust chemical solutions, and is not sustainable. There are also several other key drivers and changes in the mineral industry that clearly warrant a new approach. In response to these, an intense effort was made at Cytec over the past fifteen years to develop a meaningful, efficient, and sustainable approach to develop new reagents and robust chemical solutions in mineral separations. This effort culminated in three important outcomes: a) development of the holistic approach, called FLOTATION MATRIX 100? process, b) novel reagents, and c) enhanced application knowledge for reagents. In this paper, the efficiency, utility and power of the holistic approach will be demonstrated with examples using both existing and new reagents in the processing of Cu-Au, Au and Cu-Mo ores.

Jan 1, 2014

By C. Y. Sun

In this paper, the development of research and practice on the separation process of fine complex Cu-S ore at a Copper Mine in south of China, was discussed. Since early 1980s, various processes were used, such as the process of bulk flotation-separation, the process of selection flotation and the process of iso-flotation. Especially when the process of selective flotation was put into operation, further development was achieved in beneficiation results, but the difficulty in separation of chalcopyrite from pyrite has not been solved yet, so causing a poor quality of Cu concentrate. The author has successfully developed a new separation process characterized by the use of collector thionocarbamate and fast flotation. The selectivity of fine chalcopyrite and pyrite was greatly improved. This process supplied a new route for the treatment of fine complex Copper sulphide ores.

Jan 1, 2014

By E. Isokangas

The production of minerals for economic use is a two-stage process, involving mining to extract the mineral from the ground, and processing to convert the mineral into a marketable product. Generally, mining and processing have been viewed as self-contained entities. Both have separate objectives, separate cost centres and key performance indicators (KPIs) that do not reflect the customer/supplier relationships that inherently exist. However, mining and processing operations are inter-connected and therefore intimately inter-related with the performance of one operation affecting the performance of another. Optimizing each stage separately without considering the whole system often misses potential economic benefits and energy savings. During the past fifteen years, the authors have been involved in implementing a holistic methodology ?Mine to Mill Process Integration and Optimisation (Mine to Mill PIO)? to maximize the overall profitability of the operation rather than just optimizing any individual process in a mining operation. Metso Process Technology and Innovation (PTI), along with their project partners, have conducted several projects to significantly increase their production- generating typically 5% to 20% higher throughput and improve the overall mine and concentrator performance through PIO methodology. This proven methodology has applications ranging from greenfield projects to long-standing operations with AG/SAG, HPGR or conventional grinding circuits. This paper explains the Mine to Mill PIO methodology and discusses the benefits of such an approach on the energy consumption, the overall costs and benefits of mining operations. The paper also summarizes several case studies illustrating the use of PTI methodology in a variety of applications. Keywords: integration, optimization, simulation, modeling, mine-to-mill, comminution, blast, drill, crushing, grinding

Sep 1, 2012

By Hamid-Reza Manouchehri

"Sustainability calls for maintenance, rational use and enhancement of natural resources as well as balance consideration of ecology, economy, and social justice. The challenges in mining industry call for a sustained global effort using the leverage of available technologies and emerging new technologies. The industry uses significant amount of energy with the highest portion in comminution. To conserve energy, attempts have been made to improve the efficiency of the conventional crushing and grinding equipment. Nevertheless, the new and energy efficient comminution technologies are favorable through a longer term strategy. Since crushers are more energy efficient than mills, it is logic to conduct part of milling, in the crushing stage. After years of research and development, Sandvik introduces a new crushing technology, VibroconeTM, to change traditional crushing concepts. The new crushing device is able to crush and grind particles with a higher reduction ratio, more than two fold, than that of conventional crushers. By implementation of the new technology, a suitable feed size for milling can be provided to conserve energy as well as media and liner consumption, to reduce milling circulating load or increase mill capacity. There are other benefits associated with this machine, one of them being providing a higher surface area. This paper discusses the performance of the machine and its applications for comminuting different ores."

Jan 1, 2014