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By Graeme Lamson, Rene Dobbe, Merle Kalstrom, Janice Baron, Robert Thorpe, Chris Martin, Snezana Bajic, Amanda Palko

"This paper presents early results from a case study at the Mount Polley porphyry copper mine in British Columbia, Canada. Daily mineralogical data was acquired and reconciled with daily plant assay and recovery balances to interrogate the mineralogical controls on plant performance. After commissioning, the Minesite machine operated smoothly and reliably, creating daily data to generate mineralogical balances around the circuit for a period of several weeks. The key data, on final products were produced within 13 hours of the end of the respective operating period. The resulting information allowed for a greater understanding of the opportunities and limitations of the Mount Polley metallurgy. In this paper, how this information can be used to help long term strategic planning for the operation, as well as mine planning and production forecasting and the fine tuning of day to day mill operations is described. Early data available at the time of preparing this paper indicated that roughly 40% of the sulphide losses, or 32% of total copper losses existed as low grade inclusions in +75 micron tails. This represented the dominant form of long term copper losses, demonstrated repeatedly in the routine analytical data. However, on a day-to-day basis, the amount of copper present as chrysocolla is the major driver behind variations in total copper recovery. The degree to which this influences mill recovery is valuable to the geologist or mine planner. As they are armed with mineral speciation information for future ores, this will allow for improved mine planning, prediction of copper recoveries and production forecasting. The data was also started to find value in the mill by showing what caused sulphide losses. In the roughers, for example, the data showed poor recovery was the result of poor flotation performance and not any changes the speciation of copper sulphides or their liberation characteristics."

Jan 1, 2014

By D. Saramak

The proposal of the nip zone angle determination in HPGR crushing process is presented in the paper. Knowledge of the nip zone angle value, in turn, makes it possible to determine the real maximum pressing force in the high-pressure comminution. Two methods of determination of this maximum pressure were proposed and verified. The first method is based on the roll?s geometry, and the change of the HPGR chamber?s volume together with the roll rotation, while the second one considers the outlet gap width impact. Results of the nip zone angle calculations according to both methods are similar and show convergence with the real operating conditions. The verification was carried out in a piston-die press, and experimental results show that methodology of the nip zone angle determination presented in the paper has its practical confirmation. A proper determination of the nip zone border makes it possible to calculate the comminution probability of given type of material and is a basis for the HPGR crushing process modeling and optimization. Keywords: HPGR, comminution, nip zone, ore processing

Sep 1, 2012

By Gustav Hawlitschek, Henrique Kahn, Carina Ulsen, Renato Contessotto

"The problems related to waste dumping increased with the growth and development of large cities. In the U.K., more than 50% of landfill waste comes from construction use and the U.S. alone produces around 200 to 300 million tons of CDW annually. The exhaustion of natural sand deposits close to large urban centres stimulates the recycling of construction and demolition waste for the production of recycled aggregates as a construction material. This paper presents a flowchart for the production of recycled sand with low porosity and regular shape by the selective removal of the cement paste attached to recycled aggregates. The products characterization was carried out by the determination of the particle size and shape distribution, chemical and mineralogical composition, heavy liquid mineral separation and quantification of all present phases using a scanning electron microscopy with automated image analysis (SEM-MLA). The comminution of CDW by vertical shaft impact crusher made possible the production of a lower porosity recycled sand. The heavy liquid mineral separation showed that the proportion of low porous phases (d>2.5 g/cm3) is very high, exceeding 70% of the weight, encouraging further mineral processing separation to obtain a fine recycled aggregate with less cement paste content. The mineralogical characterization by XRD and SEM indicates that the main phases are tectosilicates, phyllosilicates and calcite which one can be attributed to both calcareous aggregate and cement paste. The precise quantification of cement paste and calcite/dolomite alone is just possible by automated image analysis. The characterization results demonstrated that proportion of phases with no cement paste attached increases progressively in denser products. The results of heavy liquid separations and image analysis are comparable and automated image analysis can be used for the characterization of phase content and their main associations."

Jan 1, 2014

By G. P. Wong

"In the Inco matte separation process, a slow-cooled converter matte is separated into three main discrete mineral phases: chalcocite (Cc), heazlewoodite (Hz) and a Cu-Ni-Fe alloy. After magnetic removal of the alloy, Cc and Hz are separated by flotation at pH>12 with diphenyl guanidine (DPG) as both collector and frother. High selectivity is achieved in rougher flotation. However, in later flotation stages such as in the middlings circuit, as oxidation takes place, Hz becomes highly floatable, resulting in a very poor separation between Cc and Hz.Starch and dextrin as Hz depressants were evaluated on the middlings circuit feed and showed no positive impact on Cc/Hz separation selectivity. Ethylene diamine tetra-acetic acid (EDTA) extraction showed the existence of abundant surface Cu and Ni ions. The use of triethylene triamine (TETA) or EDTA in flotation did not improve Cc/Hz separation selectivity. Microflotation tests were carried out on pure synthetic Cc and Hz minerals. It was found that Hz did not float in the presence of DPG. However, Hz conditioned with either copper sulfate solution or in contact with Cc floated readily in the presence of DPG. It is concluded that the major reason for Hz flotation in the middlings circuit is due to Cc oxidation releasing Cu ions that adsorb on the Hz surface making it reactive with DPG thus rendering the Hz floatable."

Jan 1, 2003

By N. Dhawan

In the last decades, High Pressure Grinding Roll (HPGR) has gained significant importance in hard rock processing due to numerous metallurgical benefits such as energy savings, particle weakening, preferential damage of coarse particles, and preferential comminution-liberation. There are a limited numbers of lab-scale HPGR units throughout the world. The laboratory-scale HPGR machine at the University of Utah is first-ever lab-scale machine designed by late Dr Klaus Schönert, the inventor of HPGR. This HPGR is constructed with two counter-rotating hardened tool steel rolls, each 200 mm in diameter and 100 mm in width. The HPGR unit is equipped with eight sensors and a robust control system, which serves as an ideal system for fundamental studies and lab-scale testing. In HPGR operation, throughput, energy and product size distribution are intricately linked to specific grinding pressure, roll gap and rolls speed. The nip angle existing during the operation determines the volume of feed material above the rolls that is pulled into rolls without slip. In this paper, scale-up factors and some of the existing models have been reviewed. A number of experiments have been carried out with limestone and a slag material. The influence of operating variables and their complex relationship has been studied.

Sep 1, 2012

By R. K. Dwari

The electrostatic beneficiation of coal is based on tribocharging characteristics of ash forming minerals and coal particles. The tribocharging of quartz, pyrite and coal particles contacted with various metals and polymeric materials have been measured and the charge acquisition is assessed through surface energy calculations from liquid contact angle data. The contact angles, before and after tribocharging of solids, are measured using Krüss tensiometer and Washburn?s method where the sample holders in tensiometer are specially constructed with tribocharger materials. The charge polarity and amount of charge acquired by quartz, pyrite and carbon with metal tribochargers were found in good agreement with the reported work functions of the contacting surfaces. The charge results with polymer materials differed from the work function values, presumably caused by surface contamination. The surface energy of quartz calculated by all the theoretical approaches in the literature showed that the tribocharging increases the surface energy. Both polar and non-polar components computed from Fowkes and Owens-Wendt-Rabel-Kaelble approaches dis-play that both these components increased after triboelectrification. However, the polar component divided into acid and base components, as in van Oss approach, manifest decreasing acid part and increasing base part. Since quartz charged negatively during tribocharging with metal surfaces and therefore accepted electrons, the determined acid and base surface energy components are consistent with charge transfer process. The results also elucidate an explicit correlation between the charges generated by powders and the surface acceptor (acid) and donor (base) electronic states and thereby the work functions. A novel fluidized bed tribocharger was designed and developed with internal baffle system for efficient contact electrification of mineral and maceral to produce high differential charging for efficient separation. The results achieved on coal with 45% ash content are presented and discussed.

Jan 1, 2014

By O. D. Khmelnitskaya

The research on selecting of an efficient technology of pyrite cinders complex treatment, sulfuric acid production wastes, have been made. The grades in the initial product were 2.04 g Au/t, 35.0 g Ag /t, 0.38%Cu, 1.1% Zn. Laboratory tests on cyanide technology, thiourea and sulphite leaching were carried out. Magnetic and flotation beneficiation and biohydrometallurgical technology were tested. After considering the results of the tests, the most economically efficient technology of pyrite cinders complex treatment with cyanide leaching of precious metals was determined. The technology involves water washing of soluble copper and zinc compounds, lime treatment and cyanide leaching of gold and silver, detoxification and utilization of mineral wastes. The precious metals are recovered from solutions by cementation onto zinc. Copper is recovered from rinse waters by SW/EW and then zinc is precipitated as hydroxide. All the solutions and organic agent are used in recirculation and therefore the technology is practically waste-free. Mineral wastes can be used as iron-containing materials for cement industry. The technology has been tested in pilot-plant scale under continuous operation with complete re-circulation of cyanide solutions. In this process recovery of 54% Au, 45% Ag, 30% Cu and 50% Zn has been achieved.

Jan 1, 2014

By N. S. Phala

Declining gold grades, mineralogical complexity of ore bodies, increasing input costs, more stringent conditions in the licenses to operate, and uncertain gold price dynamics combine to exert significant ongoing pressure on margins of gold producers. Innovative approaches of extracting the metal from its ores are required to realize value from existing and future assets. In a conventional gold processing plant, size reduction of mined ore to produce floatable or leachable product is a significant cost contributor. A step change in cost reduction will be attained if radically energy efficient grinding approaches can be developed, replacing tumbling mills. In the path towards that goal, some quick wins are possible through waste rejection before grinding, and pre-treatment of mill feed to reduce grinding energy demands. Gold locked in complex mineralizations puts pressure on margins by increasing cost per oz (typically high $/t and low metal recoveries) in the hydrometallurgical steps. Gold miners are primarily price takers. The current narrow range of gold uses (predominantly investment and jewellery) is not an entirely desirable state. Some diversification into commercial uses would potentially be a price stabilizer. In this paper, promising research directions, some not always fully explored in the gold metallurgy research space, are highlighted to stimulate radical innovation for substantial value enhancements. The author strongly believes a shift from a traditionally conservative and incremental innovation approach to a more aggressive one, across all aspects of the gold metallurgy value stream (processes to products), is what the industry needs. Keywords: gold metallurgy value stream, thiobaccilus ferroxidants, HPGR

Sep 1, 2012

By S. Owada

A national project of ?Establishing ?Green-Hydrogen (G-H)? Society in Honjo-Waseda Area? is now being developed by Waseda University together with four other universities and ten companies. The project involves three tasks of technological development of, (1)?G-H? production, (2)?G-H? refining, transportation and storage, and (3)?G-H? utilization. This paper focuses the first task of ?G-H? production from aluminium dross. We developed the physical treatment process by combining selective grinding with vibrating rod mill and electrostatic separation, in order to produce two kinds of materials, one is metal aluminium concentrate to recover it and the other is raw material to produce ?G-H? and aluminium hydroxide which can be generated by the treatment with sodium hydroxide aqueous solution. Here, we described the concentration mechanism of metal aluminium in the selective grinding and electrostatic separation and proposed a separation flowchart for optimizing the ?G-H? system in Honjo-Waseda area.

Jan 1, 2014

By Antony Amberg, Gonzalo Saldías, Romke Kuyvenhoven, Catherine Souza, Heriban Soto, Francisco Soto

"Vizcachitas is an advanced stage copper–molybdenum porphyry deposit, fully owned by Los Andes Copper and located in Central Chile. The property contains an indicated resource of 1,038 million tonnes grading 0.37% Cu and 0.012% Mo, and an inferred resource of 318 million tonnes grading 0.345% Cu and 0.013% Mo (Coffey & Alquimia, 2014). The deposit occurs in the same geological belt as several other giant copper-molybdenum porphyry deposits including Río Blanco-Los Bronces, Los Pelambres-Pachon and El Teniente. In 2018, the original Preliminary Economic Assessment (PEA) study from 2014 was updated; this paper presents the geometallurgical testwork that was performed to support that update. The testwork focused on the metallurgical characterization of 40 DDH samples and the development of a more profound orebody knowledge by relating geological features with metallurgical performance. The scope of work included complete chemical and mineralogical QemSCAN characterization; SAG, ball mill and abrasion testing; complete rougher and cleaner kinetics including locked-cycle-test; environmental ABA and settling tests on rougher tailings. The results show that the ore can be classified as medium-hard, with a hardness that is slightly below the average for large Cu/Mo deposits in the region. A good correlation was found between lithology and breakage characteristics, implying that the specific energy consumption (kWh/t) is well correlated to rock type. The results of the flotation tests were very encouraging and did not show significant variability. An overall Cu recovery of 91% can be expected for the flotation circuit. The use of a relatively coarse primary grind size gave good final recovery and grade for both Cu and Mo, and deserves further attention in future work, as this impacts positively both energy consumption and water recovery.INTRODUCTION Los Andes Copper Ltd. is a Canadian exploration and development company focused on the acquisition, exploration and development of advanced stage copper deposits in Latin America. The company owns 100% of the Vizcachitas project in Chile, the largest copper deposit in the Americas not controlled by the majors. Vizcachitas is a copper-molybdenum porphyry deposit, located 120 km north of Santiago, in an area of very good infrastructure."

Jan 1, 2018

With rapid development of Chinese iron & steel industry, it is of significance to intensify the utilization of domestic complex iron ore resources. The tin, zinc-bearing complex iron ores are typical polymetallic and intractable ones because of the complicated intergrowth relations among the multi-elements, and they have not been efficiently utilized, presently. Based on the thermodynamic analysis of iron, tin and zinc oxides reduction by CO, the technological conditions of tin and zinc recovery and pellets preparation from tin, zinc-containing iron concentrates by selective reduction roasting are studied and a new comprehensive utilization process is developed in this investigation. Under the optimum conditions, the tin and zinc volatilization is respectively in excess of 80% and 70%, and the compression strength of roasted pellet is more than 2500 N/P. Moreover, the residual tin and zinc in the finished pellets is below 0.06%. The finished pellets can be used as high quality iron-making burdens for large-scale blast furnace.

Jan 1, 2014

By K. Kiangi

On installing the Metso Superior MK 54x75? primary gyratory crusher in Nkomati mine the crusher experienced severe power spikes greater than 1000kW which subsequently led to the crusher tripping under load while processing some of Nkomati?s MMZ ores. Likewise significant losses in throughput were also experienced while processing some of Nkomati?s MMZ ore types. Interestingly the crusher was capable of processing the PCMZ ores without experiencing any power spikes or losses in throughput. Investigations into the challenges faced by the crusher while processing Nkomati?s MMZ ores were conducted using the DEM model in conjunction with the fast breakage model present in Metso?s High Fidelity Simulator. The intentions of the study were to establish the most suitable operating conditions or cavity design that would potentially enhance the performance of the crusher. Likewise an understanding of the effects the feed conditions (size distribution and hardness) had on the crusher?s performance was established. Ore characterization tests were conducted on Nkomati?sPyroxenite, Diabase, Calc silicate and quartzite ores which were from Nkomati?s MMZ ore body. The ore characterization tests conducted were drop weight tests, slow compression tests and elastic modulus tests. Four simulations were conducted used the existing cavity design with various open side settings (OSS) and throws. This established the effects of changing the crusher?s operating conditions on its performance. Four additional simulations were conducted on two cavity designs with reduced volumes. This established the effects of changing the crusher?s cavity design on the crusher?s performance. Thus through the simulations a better understandings of the impact of the crusher design, operating conditions and feed conditions on the crushers performance. Furthermore an analysis of the crusher?s performance was made which was used as a basis for comparisons with the base case simulation. Keywords: crusher, discrete element method, simulation, ore characterization

Sep 1, 2012

This study examines the surface alteration and flotation behaviour of synthetic moncheite, PtPd(BiTe)2, in the presence of pentlandite. The telluride minerals contribute around 20% ~ 30% and up to 45% of the PGM present in the Platreef ore and are considered to be slow floating as there is evidence of these minerals reporting to the tailings. It was proposed that oxidation products from other minerals and grinding media would affect the mineral surface composition and floatability thereby causing inadvertent depression of moncheite due to precipitating ions. ToF-SIMS analyses (time of flight secondary ion mass spectrometry) was used to characterise the mineral surface as well as the extent of surface alteration. Microflotation was used to deter-mine the hydrophobicity of the synthetic minerals. Conditioning of moncheite in the presence of pentlandite reduced the flotation response of the + 38 -106µm size fraction from > 99% to 56%. This was due to pentlandite dissolution products (iron and nickel hydroxy species) which formed overlayers on the mineral surfaces thereby inhibiting the adsorption of collector. In addition, further grinding of these samples, with and without pentlandite conditioning showed a negative effect on recovery due to the fineness of the particle size distribution and there was no advantage gained from any possible exposure of fresh sites in the sample.

Jan 1, 2014

By M. Canbazoglu

In this study, optimum sulphuric acid leaching parameters of zinc and other valuable metals from two different waelz clinker samples were researched. Origins of the samples are electric arc furnace dust and original non-sulphite zinc ore waelz clinkers. The main zinc mineral determined as zincite in these samples. Collective dissolution of zinc and other valuable metals in waelz clinkers can easily achieved by sulphuric acid leaching of them. 96% of zinc can be dissolved at 80 ºC, 60 g/L sulphuric acid concentration, 60 min. leaching time and 1/5 solid/liquid ratio. Almost 90% of Cd, Cu and Co in clinker dissolved at these conditions while dissolution of Fe was almost 20%. The consumed acid amount for dissolved per ton of zinc is approximately 1.7 tons at these conditions.

Jan 1, 2014

By V Radmehr

Ammonia and Amonium salts have been recognized as effective leaching agents in hydrometallurgical processes due to low toxicity and cost, easy recovery and high selective recovery of metals. New research findings of considerable advantages of leaching by these agents and elimination of problems associated with acid leaching has resulted in a new approach in the world to this method. The investigations in this field indicate more frequent use of this method for extracting copper from ore and concentrate relative to other basic metals. In this paper, we have attempted to describe the basis and different ammonia leaching methods and present the major research activities in this field for copper. We have also presented the latest findings and related novel processes. Comparative assessment of advantages and disadvantages of this method relative to acid leaching method, kinetic study of copper ammonia leaching and evaluation of Eh-pH diagrams in a system containing water and ammonia are other parts of our study. Finally, by describing the studies on copper extraction from the resulting pregnant solutions, the applicable extraction agents have been reviewed.

Sep 1, 2012

By S. M. Viduka

This paper presents a numerical investigation of solid separation in jigging device, which is a gravity separation method widely used in ore processing. Separation is recognized as being heavily dependent on fluid motion in the jig. This study explores the effects of the inlet time dependent velocity profile on jigging performance. Modelling of the liquid-solid system is performed through a combination of computational fluid dynamics (CFD) to simulate liquid flow and discrete element method (DEM) to resolve particle motion. The initial packing conditions consist of a binary-density particle system of 1130 particles each 1 cm in diameter. A variety of jigging profiles are implemented in jigging. The saw tooth pulsation profile is selected with three variations in both amplitude and frequency. The performance of each profile variant is compared in terms of solid flow patterns, separation kinetics, energy, and mean particle position. These quantitative comparisons demonstrate significant differences in the segregation rate, energy, and solid phenomena, helping find an alternative optimum operating setting for the system.

Sep 1, 2012

By Z. Q. Zhang

The iron ore from Yichang in China assaying 41.64% Fe and 1.02% P is a low grade and high phosphorus oolitic hematite ore. The separation of iron minerals from gangue minerals in the ore by conventional processing techniques is ineffective owing to their close similar properties. The modification of iron minerals by microwave-assisted reduction was investigated in order to improve separability of the ore. The effects of microwave-assisted reduction on the subsequent low intensity magnetic separation and floatation were examined. The results show that the main factors affecting the reduction and separation process are grinding size, reduction temperature and reductant. Fine grinding of the microwave-treated ore to smaller than 0.074mm was found to be imperative due to the tiny dissemination characteristics of iron oxide minerals. After magnetizing reduction by microwave heating at 500?, the magnetic concentrate containing 58.36% Fe and 0.67% P can be obtained with the Fe recovery of 91.28%. Magnetizing reduction drops the floatability of iron oxide minerals, thus reverse flotation is fit for upgrading the magnetic concentrate to contain 62.13% Fe and 0.21% P with Fe recovery of 81.59%. Compared with present microwave-assisted reduction technique of carbon reductant, using a waste iron powder as reductant is a novel and effective technique without the green house effect caused by the release of CO and CO2. Waste iron powder with a faster response to microwave heating then coke and charcoal can be recovered by magnetic separation in a low cost and plays the role of reductant and microwave heating accelerator.

Jan 1, 2014

By Xiaoming Wang

This paper presents an arcuate magnetic separator to remove the grinding ball fragment directly from the mill discharge, which will cause wear to downstream processing equipment such as pump, hydro cyclones and pebble crusher. Furth more this type separator was applied in Wushan mine under China National Group Corporation in China. After months of operation, the equipment has been a success. It removes majority of ball fragments from mill discharge. Keywords: magnetic separator, sag mill, pebble crusher, grinding ball fragments

Sep 1, 2012

By Zhou Yucai, Zhou Jing, Zhu Yimim

"In this article, research on the beneficiation process for a carbon containing copper-molybdenum deposit in Henan province has been carried out. The elemental composition, mineral composition and relative content, characteristics of embedded and symbiotic relationship, the forms of the copper-molybdenum particlesand their disseminated features, and particle size distribution have been worked out. Flotation behavior of copper-molybdenum mixed flotation and separate flotation in the systems of different collectors and depressants, and the influence of different flowsheets on the copper-molybdenum separation have been investigated by actual ore flotation tests, The separation problem of copper-molybdenum for a carbon-containing copper molybdenum ore has been solved.INTRODUCTION In this paper, technological mineralogy, small experiment of flotation recovery of copper Molybdenum ore, and expansion experiment of mineral recovery of copper Molybdenum ore are introduced. (1) The results of process mineralogyshow that the content of copper is 0.42%, molybdenum is 0.021% in the raw ore, they mainly exist in the form of sulfide, with low oxidation rate. (2) The results of flotation tests show that the combination of butyl xanthate and isopropyl ethylthionocarbamate reagents is effective collector of copper-molybdenum mixed flotation for carbon copper molybdenum, (3) When the grinding fineness is -0.074 mm taking 71%, and regrinding fineness is -0.038 mm taking 85%, the flowsheet of first copper-molybdenum mixed flotation and then regrinding rough concentrate and last separation flotation of copper and molybdenum was adopted, which realized the effective separation of copper and molybdenum for carbon-containing copper molybdenum ore. Good flotation indexes were gained with copper concentrate containing 20.96% copper and copper recovery 90.06%, and molybdenum concentrate containing 46.78% molybdenum with molybdenum recovery 72.68%. (4) The seven days average concentration index of scale-up the continuous dressing experiment is as follows, the copper content in copper concentrate is 20.16% and the recovery is 89.61%; the molybdenum content in molybdenum concentrate is 24.58% and the recovery rate is 74.09%."

Jan 1, 2018

By A. Kurkov

Flotation process is based on the formation of primary collector-based supramolecular associates at the mineral surface and within the pulp. Supra molecular chemistry allows studying within a common framework, all kinds of molecular associates, from dimers to large assemblies, resulting from spontaneous association of a large number of interacting components of the flotation system, where the collective action of non covalent bonds can have an important role. Self-organization of supra molecular assemblies in the flotation process can be controlled by modifying the chemical structure of the collector, the nature and arrangement of functional group in it, by introducing secondary agents (SA) into the process, to adjust the interaction between the collector and the surface and to control the hydrophobicity of the adsorption bed. This offers broad opportunities to build supramolecular assemblies to improve the efficiency of flotation. Besides, the more complex is the system, the weaker are the interactions, that determine its behavior. This powerful factor still is not employed deliberately to control the flotation process. Organophosphorus compounds (OPC) - dialkyl phosphoric acids whose radicals contain ethoxylated groups ? are considered as nanocompounds, that can be used in building supramolecular assemblies. The presence in an OPC molecule of functional groups (P=O, P (O) O-, P (O) OH), ethoxylated groups, and aromatic rings is the basis for the formation of stable supramolecular associates. Gross formula: C54H94KO16P. Molecular weight is 1069.39. Phosphoryl anion has a regular tetrahedral structure with the angle of 109.5°. Lengths of -P-O- bonds in a PN molecule are 1.7345Å; length of the hydrocarbonic radical C42-C72 = 33.942Å. In an alkaline environment, PN is in the form of the anion, in an acidic environment ? in the form of the polycation due to protonation of the oxygen in the EO group. Chem Office software suite was used to generate three-dimensional images of an OPC molecule in acidic and alkaline environments, to reveal the OPC geometry (bond lengths, valence angles, aliphatic radical length), to identify the collector's binding sites with the mineral surface, to find the most stable and energy-efficient molecular conformations of an OPC molecule and its complexes with minerals under various conditions. Mechanisms of interaction between OPCs and the mineral surfaces are different. In ores whose minerals are dominated by ionic bonds (fluorite), the interaction mainly involves the anionic form of the collector; in ores, whose minerals are dominated by covalent bonds - the oxygen of the phosphoryl group (donor-acceptor interaction) and the oxygen of the ethoxylated groups. This difference is responsible for the formation of spatial associates with different surface layer structures. Introduction of supramolecular chemistry concepts into the analysis of flotation phenomena and mechanisms can become an effective tool for better understanding the flotation process and offers new means of consistently improving its effectiveness.

Sep 1, 2012