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By Samantha Beeson, Collin Poole

"This paper examines the development of two new selective flocculation techniques for recovering KCI values from low grade carnallite potash ore.Direct recovery of KCI was achieved using one of two mid-range molecular weight polymers, one non-ionic and the other strongly cationic, in conjunction with the same selective anionic dispersant. From initial response studies on pure minerals and selective flocculation tests on synthetic mixtures, investigations were extended to recover KCI values from a natural carnallite potash ore. A single-stage process achieved products grading up to 61.3% KCI at recoveries up to 85.4% for the cationic flocculant suite and up to 64.8% KCI with recoveries as high as 90.3% for the non-ionic flocculant suite, with dispersant and flocculant dosages of 150-250gr1 and 10-75gr1, respectively. These results clearly demonstrate not only the feasibility of treating such problematic ores at low reagent dosages, but also the potential elimination of desliming prior to froth flotation.The experimental results presented are considered in terms of the reagent adsorption phenomena present in the system and various aspects of floe formation and cleaning.IntroductionAs high-grade sylvinite potash ores become scarce, lower grade sylvinite and carnallite potash ores are becoming more attractive. However, these ores often contain large amounts (up to 15% by weight) of water-insoluble slimes which must be removed prior to KC! flotation, owing to their high adsorptive capacity for the amine collectors used. The slimes are generally removed by scrubbing followed by hydroclassification and any residual material not eliminated is blinded with reagents such as guar gum or starch to inhibit interference in subsequent KC1 flotation.An alternative approach used commercially in Canada by Agrium Inc. involves water-insoluble slimes flotation prior to KC! flotation. In this process, the slimes are selectively flocculated and then separated by froth flotation. Losses of KC! to the slimes product and associated brine requirements are both reported to be less than those encountered in conventional desliming, but the technique is somewhat limited in its application at present."

Jan 1, 1997

By Klaus Tietz, Hamish Adam, John Selby, Ian Glazier, Brian Sinfield

"Room-temperature tunable diode laser (TDL) analyzers are gaining in acceptance for highly critical safety monitoring applications in a variety of industries. This paper describes the testing, evaluation and deployment of a laser-based hydrogen cyanide monitoring system at the Campbell Complex of Goldcorp’s Red Lake Gold Mines in Balmertown, Ontario, Canada.A trial, single channel installation was followed by a staged multi-channel installation. Unexpected technical issues with the multi-channel installation were addressed and resolved.INTRODUCTIONLaser-based gas detection has several advantages over existing gas detection techniques (Ballangrud, 1993; Silver, 1992; Bomse, 1995; Table 1). For practical purposes, lasers generate light at a single wavelength. Room temperature tunable diode lasers (TDL) emit light in the near infrared (NIR) part of the electro-magnetic spectrum. Many gases of interest, including HCN, NH3 and others, absorb energy in the near infrared (NIR). Each gas has a unique absorption signature, or spectrum, made up of a large number of individual “absorption lines”. A TDL can be tuned to select a single absorption line of a target gas, which does not overlap with absorption lines from any other gases. Therefore, laser gas sensing is selective and does not suffer from interference from other gases. The single-wavelength nature of laser light also means that laser gas analysers have a linear response over a wide dynamic range.Tunable Diode Lasers (TDL) generate only a few mW of power. However, all this power is concentrated at one wavelength, the wavelength where gas absorption occurs, resulting in high signal-to-noise ratios and short response times, typically of about 1 or 2 seconds (Ballangrud, 1993). This also means that long path lengths can be used, enabling accurate measurements of very low concentrations, even with weakly absorbing gases. Tunable Diode Lasers provide all the advantages of other semiconductor devices: they are small, solid-state devices, operate at room temperature, and have long-term reliability (over 15 years). Currently, they can be obtained for any wavelength throughout the NIR (700nm to 2000nm). Because many gases absorb in the NIR, the technique is widely applicable."

Jan 1, 2011

By Robert E. McIvor

"“Classification System Efficiency (CSE)” is a powerful, emerging tool that can be used to increase grinding circuit efficiency. It is defined as the percentage of the ball mill energy being used to grind target, oversize particles. The discovery, validation and current use of CSE, including how it was manipulated, are described through seven plant case studies. These resulted in efficiency improvements ranging from 3 to 30 percent, along with major reductions in over-grinding. The achievable CSE for any given circuit is described. This paper demonstrates both how, and how much, every plant can benefit from increasing grinding circuit CSE.DEFINITIONS: BALL MILL CIRCUIT “CLASSIFICATION SYSTEM EFFICIENCY (CSE)”, “EFFECTIVE MILL GRINDING POWER”: “WASTED/OVER-GRINDING MILL POWER”The closed ball mill circuit is shown in Figure 1. The extreme importance of the circulating load ratio in determining circuit productivity was demonstrated by Davis (1925) and re-published by Guadin (1939), as shown in Figure 2. The circuit production rate increases with increased circulating load ratio, rapidly so at first and continuing to increase more gradually with higher and higher values of circulating load ratio.The underlying cause of this relationship was seen when comparing the ball mill feed and product size distributions from two different ball mill circuits, one with a low circulating load ratio, and one with a high circulating load ratio (Figure 3). While the F80’s and P80’s of these two circuits were close to the same, the mill feed and discharge size distributions were quite different. The ball mill in the circuit with the higher circulating load ratio contained a substantially greater fraction of material coarser than the target P80, as indicated by the respective mill feed and discharge size distributions. This fraction represents the fraction of the mill power being expended on “coarse” (in this case, plus P80 size) material, or the circuit “classification system efficiency.” The “effective mill grinding power” is the total mill power multiplied by the CSE. The compliment of CSE, the remaining fraction of “fines” in the mill, is the fraction of the mill power being wasted, and spent on over-grinding of material already finer than the circuit target product size. This is the “wasted/over-grinding mill power”"

Jan 1, 2013

By Eugen Gluck, Gus Van Weert, Peter Kondos

"Microwaves have the capability to heat up sulphides, especially clusters of particles of approx. 1 mm. Some sulphides absorb microwaves more readily than others. Molybdenite is especially effective in this regard, possibly due to its flaky nature and/or electrical conductivity. Even where it occurs in low concentrations in a deposit, individual rocks may be ore grade due to the high monetary value of MoS2. Such rocks often result from crushing mined veinlets or stockwork, or are contained in the cutoff grade fraction of ROM. Machine segregation of rocks high in MoS2 by infrared sensors after microwaving could therefore advantageously be used to upgrade lower grade ore between Mine and Mill. This would reduce the size of the latter, and thus its CAPEX and OPEX. Such upgrading could also yield shipping ore for a distant Mill, or extend ore reserves.Barrick Gold Corp. has been supporting the development of MW/IR sulphide sorting for the past three years. The results of MW/IR sorting work on molybdenite and other (pyritic) ore samples from a variety of sources are being presented here.INTRODUCTIONThis paper looks at mechanized, i.e. machine ore sorting technologies currently available and under development, and what conditions would be needed for the potential application of such ore sorting to sulphide mining and milling. Current machine sorting involves no-contact sensing technology for rocks, and signal processing after sensing to activate airblast segregation of certain rocks, normally the smallest mass to keep compressed air costs down.The forerunner of modern sorting is probably magnetic separation, which utilizes an inherent property of certain ores to divert it into mag and non-mags fractions. Radiometric ore sorters, which have been applied successfully for decades in the pre-concentration of uranium ores (Wotruba and Riedel, 2006) initiated modern sorting. In the 90’s, sensor-based machine sorting became a viable means of increasing the overall economic recovery of a resource. This technology became driven by the availability of low cost computing equipment and the concurrent development of algorithms, and by the availability of extremely fast response sensors and air actuators, allowing the sorting equipment to run faster, dropping the cost per tonne. It has been in industrial minerals processing that rock sorting has been most widely adopted, not really surprising. Liberation occurs on a different scale than in the base metal industry. Most industrial minerals are mined from massive deposits, requiring (in the past) no upgrading. Many of these operations now run into product contamination problems, which ore sorting can solve. One illustration: in Finland, a quarry is separating limestone from dolomite at 500 tonnes / hour, with individual rocks weighing up to 15 kg. Many of these industrial minerals operations have stockpiles of earlier discarded below-quality rocks, now being reprocessed with the help of ore sorting. The economics of this are very favourable, going from zero or negative value (stockpiles can not be left when closing the mine) to full product value for at least a portion of the stockpile. This suggests that in the future the economics of overburden sorting could become attractive under the right circumstances and such treatment could well become an integral part of open pit mine development."

Jan 1, 2009

By Hiroaki Sakurai

Using batch reactors equipped with CO and CO2 gas sensor, CO oxidation over Au catalysts in room air has been investigated and compared with Pt catalysts. For both Au and Pt catalysts, the logarithm plot of CO concentration data during initial 10 min are well fitted by straight line, which mean the first order dependence on the CO concentration between 10 and 10,000ppm. The rate constant value (k) over Au and Pt catalyst generally decrease with increasing initial CO concentration above 100ppm. The value decrease especially rapidly between 100ppm and 1,000ppm over Pt catalysts, which should be due to the strong adsorption of CO on Pt. The k value over Au catalyst has become ten times or more as large as the Pt catalysts at 1,000ppm. Already for the initial concentration of 100ppm CO, the strongly adsorbed CO on Pt metal has been clearly observed by FT-IR during the reaction over Pt/Al2O3. A part of the strongly adsorbed CO has been remained on Pt after the disappearance of gas phase CO, and has gradually changed to gas phase CO2. Such strongly adsorbed species on Au has never been observed on Au/TiO2 under the same reaction conditions. These features of Au catalysts are favorable for indoor air purification.

Oct 1, 2003

By Ken Dyck Sr.

"Construction of the Cigar Lake uranium mine in northern Saskatchewan is well under way. Production is anticipated to begin in the first half of 2007. When in full production, the mine is projected to produce a net 18,000,000 pounds of U3O8 per annum from a high grade ore averaging approximately 20% U3O8.Water management was a major issue that required substantial effort in the Cigar Lake design. Not only is effluent quality controlled, a tight water balance to minimize effluent volume is also designed into processes in order to minimize environmental impact. This paper focuses on the water treatment process and water handling equipment, as well as the operating philosophies that will reduce fresh water consumption to a minimum. An overview of the mining and ore handling systems, as well as aspects of controlling water production from the ore formation and the mine development areas will also be discussed.INTRODUCTIONThe Cigar Lake ore body has proven and probable reserves that total 232 million pounds U3O8. Cigar Lake is the world’s largest undeveloped high-grade deposit. It is the second largest highgrade deposit surpassed only by the McArthur River deposit another Cameco - operated mine in the Saskatchewan Athabasca Basin. Cigar Lake is owned 50% by Cameco Corporation, 37% by AREVA (COGEMA Resources Inc.), 8% by Idemitsu Uranium Exploration Canada Ltd. and 5% by TEPCO Resources Inc. When production starts in 2007, ground ore slurry from Cigar Lake will be shipped to the McClean Lake mill (owned by AREVA) some 80 km away. All of the Cigar Lake uranium will be leached from the ore at McClean Lake. During initial production ramp up, all uranium will be processed at McClean Lake to yellow cake (uranium oxide). After the average production has exceeded a 10 million pound per year rate, Cigar Lake uranium will begin to flow from the McClean Lake Mill to the Rabbit Lake Mill. At this point, subject to regulatory approval, 57% of the Cigar Lake uranium, in a uranium rich solution, will be transported to Rabbit Lake mill (owned by Cameco) for purification to yellow cake. A complete summary of the flow of uranium from the Cigar Lake ore body through to product at both McClean Lake and Rabbit Lake can be found in a recent paper titled “The Cigar Lake Project – Mining, Ore Handling and Milling” in the March 2004 issue of the CIM Bulletin. The paper was written by C.R. Edwards."

Jan 1, 2006

By Graham Davey

"Low speed stirred milling has been employed for many years in the metalliferous and industrial minerals industries. High speed stirred milling is a relatively new method of grinding in the metalliferous process industries. However it has been it has been in wide spread use in the industrial mineral field for over 30 years for various minerals. Many existing metallurgical operations are looking to maximize economic return from existing deposits, requiring new thinking and technologies. By combining low speed and high-speed milling fine and ultrafine grinding efficiency and operating costs can be improved.The correct selection of different fine grinding technologies is covered, when each mill is applicable and when a combination of the VERTIMILL® Grinding Mill and SMD provides the best economic solution.INTRODUCTIONUltra-fine grinding of minerals has been in wide spread use in the industrial mineral field for over 30 years. Within the last 10 years the metalliferous industry has shown interest in the ability to produce ultrafine particles, as chemical, physio-chemical and physical separation processes have advanced to be able to treat ultrafine metalliferous particles. Also as the primary mineral deposits, around the world are depleted, new more difficult deposits must be mined. Existing operations are also looking to maximize economic return from existing deposits, requiring new thinking and technologies.The traditional approach for gold containing refractory material has been to liberate the locked gold by chemically destroying the pyrite through oxidation. Roasting, pressure oxidation, and bacterial oxidation all employ various degrees of temperature, pressure and catalysis to react the pyrite with oxygen to produce iron oxide and sulfur by-products. However all of these methods are economically impacted due to specific operational added requirements and emissions controls. Pressure and bacterial oxidation have very high capital and operating costs."

Jan 1, 2006

By Bruce Mennie

PT Freeport Indonesia (PTFI) operates copper and gold mining operations in a mountainous area of the Mimika regency, near Tembagapura, Papua (formerly, Irian Jaya), Indonesia. The mining and concentrating operations typically produce 240,000 metric tonnes per day of Copper and Gold ore from the combined mining of an 80,000 tonne per day (ore) block cave operation (DOZ Mine) and a 160,000 tonne per day (ore) open pit mining operation (Grasberg Open Pit). The Grasberg Open pit mine will be complete in 2016 at which time PTFI?s operations will convert to Underground. Mining operations will transition from today?s mixed surface and underground operation to full underground mining over the next 6 years. This paper reviews the history of Redpath?s relationship with PTFI, beginning with a raiseboring contract in 1981 and evolving into vertical and horizontal development contracts of up to 37,700 equivalent metres of lateral development and 4,000 metres of vertical development in 2011. An overview of the current operations (PTFI?s Grasberg Open Pit and DOZ Underground Mines) and transition period (challenges for the transition from current to future underground mines) is presented with details of development of common underground infrastructure and future mines; Big Gossan Mine, DMLZ Mine, Grasberg Block Cave Mine, and the Kucing Liar Mine.

Oct 1, 2010

By A. M. Hill

"This is an account of the expansion of Texasgulf's Timmins concentrator by the building of a fourth circuit.The original capacity of the mine and concentrator was 3.6 million tons per year of ore. In 1974, Texasgulf decided to increase that capacity by about one third to 4.8 million tons per year. It was planned that the increased capacity would be available by mid-1978.The expansion involved work at the rninesite, increased railroad capacity, and a new circuit in the concentrator, and it is the concentrator expansion which is described here.In 1974, the minesite drew its ore from the open pit. The pit was being phased out and was to be replaced by No. 1 mine. To allow for the expansion, a second mine was required. The railroad was capable of handling 18 car trains. Its capacity had to be increased to 27 cars per train and this, in turn, required two new locomotives. Each of these alone cost half a million dollars.The concentrator building in 1974 contained the concentrating equipment and miscellaneous services (such as machine shop, warehouse, analytical lab). The grinding and flotation sections were divided into three circuits ('A', 'B', & 'C'). 'A' and 'B' circuits treated copper-zinc ore and 'C' circuit treated the much more difficult copperzinc- lead ore. This 'C' circuit had been modified over the years to implement improvements in the metallurgy."

Jan 1, 1979

By D. E. Pickett, J. A. Roland Faucher

"INTRODUCTIONMineral processing is undergoing growth and change at a rapid rate. The modern flotation process was discovered only in the mid-twenties, and uranium leaching in the mid-fifties. The growth of individual unit equipment size is also a recent development and is perhaps most dramatically illustrated by the increase in size and connected horsepower in grinding mills. It is also apparent in much of the equipment used in mining operations.These technical and mechanical developments have influenced the design of plants but not to the expected degree.Many metallurgists believed until recently that grinding an ore in the absence of steel results in a loEs of selectivity in the flotation. However results reported by Thornton (1), Fahlstrom (2), Canmet (3 & 4) have shown on the contrary better selectivity and improved recovery at a lower operating cost. According to the Aitik (2) plant results, the net difference in cost plus tailing value in favour of the two-stage autogeneous grinding circuit is in the order of 40 cents per ton of ore milled. Even a greater difference was indicated by the results obtained by Canmet on a sample supplied by Mattagami Lake Mines Ltd.Yet how many plants are taking advantage of these findings and how many plants are being converted. How much more improvement of the results would have been obtained if these tests had incorporated optimization of classification efficiency? By nature the mining industry and the mineral processors are conservative, and tend to emphasize the possible penalties for an unsuccessful innovation out of proportion to the potential rewards even for a significant improvement."

Jan 1, 1979

By Andy Lemay

Vale (previously known as CVRD) is: ? The second-largest mining company by market capitalization (NYSE:RIO) ? Headquartered in Brazil ? Global workforce of over 100,000 employees including outsourced workers. Vale Inco Limited is a wholly?owned subsidiary of Vale Vale Inco Limited ? is based in Toronto, Ontario Canada: ? Operations and Projects in 20 countries ? Marketing Network extending to 40 countries ? Over 12,000 employees worldwide ? Last years sales of US $8 Billion

May 1, 2008

By James R. Lang

The Xietongmen deposit is located 350 km west of Lhasa, Tibet. It is a new, high-grade porphyry copper-gold discovery and the first deposit to be systematically explored by a western company in southern Tibet. In 2005, Continental Minerals Corporation drilled 21,332 m of core in 63 holes and demonstrated excellent lateral and vertical continuity of high-grade copper-gold mineralization over an area 750 m by up to 350 m in size which remains open in all lateral directions. Drill intersections repeatedly yield grades >1% Cu equivalent (based on gold and copper prices) and include 308.5 m at 0.87% Cu and 1.25 g/T Au (1.60 CuEQ%), and 315.6 metres at 0.61% Cu and 1.11 g/T Au (1.26 CuEQ%). Extensive drilling in 2006 will expand and delineate the deposit, and metallurgical, engineering, environmental and socio-economic evaluations will begin. Xietongmen is hosted by volcanic and intrusive rocks of the Gangdese belt, a magmatic arc active between 120 and 30 Ma along the southern margin of Eurasia. Pervasive alteration is dominated by a well-mineralized K-feldspar and biotite assemblage, and by a more peripheral sericitic assemblage also with strong chalcopyrite. Major vein stages include chalcopyrite-bearing quartz, biotite, magnetite and pyrite-pyrrhotite types.

May 1, 2006

By M. W. Lewis, J. Werner

Fluctuating metal prices, declining head grade, and increased operational costs are forcing many open pit mining companies to look to their balance sheets for significant cost reductions in order to remain competitive. Maintenance continues to represent a significant proportion of the total operating costs in the mining industry. Compared with the other major cost components of the mining process, very little effort has gone into maintenance optimization. The potential payoff from maintenance optimization on the cash cost of the commodity is enormous. A large percentage of these costs are incurred in unscheduled maintenance events, which typically cause serious disruptions to the production process. These maintenance-induced production losses can be a significant contributor to the overall operating costs. A structured proactive maintenance approach using the latest advances in technology can achieve dramatic cost reductions and productivity improvements. Remote condition monitoring systems are becoming increasingly commonplace and have the potential to identify problems prior to failure. Detection of equipment degradation prior to failure will enable repairs to be scheduled thereby reducing costs and interruptions to production. Remote condition monitoring technology has evolved rapidly in recent years, with a host of new tools becoming available to assist mine operators in improving their maintenance operations. These tools have capabilities such as remote real-time vital signs and performance monitoring, alarm/event handling, trend analysis, and maintenance workflow management. When these monitoring tools are used in conjunction with a mine management system, the vital signs data can be integrated and associated with maintenance history, predictive maintenance data, operational information, and geographical information. This integrated approach to the management of vital maintenance data will help shift the mobile equipment maintenance paradigm from reactive to proactive. This paper will introduce a proactive approach to the management of the maintenance process and the tools required to facilitate this process.

Jan 1, 2005

By P. K. Frempong, S. D. Butt

"A case study for the application of a novel geostatistical technique for resource estimation of a narrow steeply dipping, gold-silver mineralized quartz vein deposit is presented. The technique is novel in two respects. First, mineral grades are kriged directly rather via the accumulation method more often applied to vein deposits and, second, a modified 2D ordinary kriging algorithm is used that allows the calculation of a single grade and variance for irregular shaped blocks of varying sizes. The objective of this investigation was to evaluate the suitability of this novel geostatistical technique for resource estimation of the Poura mine deposit and, if appropriate, to lay a firm foundation for future geostatistical work at the mine.The reserve estimation concentrated on the remnant ore blocks and pillars in both underground and surface workings. The data, which was collected in 2D coordinates with grade and vein thickness values, was first analyzed statistically and used to compute experimental semi-variograms. Appropriate semivariogram models were fitted and various aspects of the estimation technique were evaluated using cross-validation error analysis, with acceptable results. A block kriging computer program called Krige2D was developed to implement the modified 2D kriging algorithm and calculations. Production data were not available to evaluate the computed block resources, but they were compared with a previous resource data determined using an arithmetic approach. The geostatistical technique estimated slightly higher grades but lower overall tonnages as compared to the earlier arithmetic estimates."

Jan 1, 2004

A case study for the application of a novel geostatistical technique for resource estimation of a narrow steeply dipping, gold-silver mineralized quartz vein deposit is presented. The technique is novel in two respects. First, mineral grades are kriged directly rather via the accumulation method more often applied to vein deposits and, second, a modified 2D ordinary kriging algorithm is used that allows the calculation of a single grade and variance for irregular shaped blocks of varying sizes. The objective of this investigation was to evaluate the suitability of this novel geostatistical technique for resource estimation of the Poura mine deposit and, if appropriate, to lay a firm foundation for future geostatistical work at the mine. The reserve estimation concentrated on the remnant ore blocks and pillars in both underground and surface workings. The data, which was collected in 2D coordinates with grade and vein thickness values, was first analyzed statistically and used to compute experimental semi-variograms. Appropriate semi- variogram models were fitted and various aspects of the estimation technique were evaluated using cross-validation error analysis, with acceptable results. A block kriging computer program called Krige2D was developed to implement the modified 2D kriging algorithm and calculations. Production data were not available to evaluate the computed block resources, but they were compared with a previous resource data determined using an arithmetic approach. The geostatistical technique estimated slightly higher grades but lower overall tonnages as compared to the earlier arithmetic estimates.

Feb 1, 2004

By D Reddy Chinnasane

Outline Location of BirchtreeMine and Layout of 124 OB Cut and Fill Mining Background Purpose of the Studies Methodology Results and Analysis Conclusions and Recommendations

Oct 1, 2010

By Adam Wright

"Les Mines Selbaie have been producing copper and zinc concentrates from the A-1 ore zone since 1986. This paper reviews major developments in flotation practice over that period. Firstly, ore blending strategies for Selbaie's non-homogeneous polymetallic ore are discussed. The evolution of reagent use is then reviewed, focussing on copper collector trials. A description of Selbaie's flotation columns follows. Finally, past and future developments for process control are outlined.Depuis 1986, Les Mines Selbaie produisent du concentré de cuivre et de zinc provenant de la zone A-1. Cette conférence présente !es développements majeurs en flottation qui ont eu lieu depuis ce temps. Premièrement, la stratégie du mélange de minerai non homogène polymétallique est présentée. L'évolution des réactifs utilises est démontrée, particulièrement !es collecteurs de cuivre. Par la suite !es colonnes de flottation sont presénteés et finalement !es développements futurs ainsi que ceux qui ont eu lieu dans le contrille de procédé sont expliqués.1.0 INTRODUCTIONLes Mines Selbaie, wholly owned by Billiton Metals Canada Inc., is currently mining and processing ore from a polymetallic surface deposit located 288 km northwest of Val D'or, Quebec (fig. 1). The mine produces copper concentrates containing gold and silver as well as zinc concentrates containing silver. 8000 dmt/day of ore is crushed and ground to 80% passing 49 µm, prior to processing by conventional copper/zinc differential flotation. The flotation circuits consist of both conventional and column cells (fig. 2). Detailed descriptions of the mill are available elsewhere in the literature (8,9)."

Jan 1, 1995

By Karl Nienhaus

The BGMR has developed a method for an online-analysis during drilling processes in cooperation with Fraunhofer Institute for Laser Technology in Aachen and various industrial partners. This allows for efficient utilization of deposits, maximum recovery of desired minerals and frequent and costefficient updates of deposit models. The used method, namely laser-induced breakdown spectroscopy (LIBS), was implemented into a compact demonstrator in order to analyze drill dust and loosened material within mining environments and directly on drill rigs. The consequently developed OFURanalyzer (OFUR ? online-analysis of mineral deposits) provides possibilities for exploration and visualization of deposit models in real-time and thus creates an opportunity for innovative applications, such as contactless, continuous quality control of minerals throughout the extraction process. A major challenge in the execution of this project was the necessity to develop a laser system that could withstand rough mining environments dominated by dust, shocks, vibration and therefore would be suited to operate under such conditions.

Oct 1, 2009

By J. Sliwinski, J. Oliveira

"The application of geometallurgy and corresponding sample selection can take on several formats within industry. Current practice can range from a strictly geostatistical approach to one in which geological and metallurgical parameters are used in combination to create a representative sample selection strategy. The stage of a project and the level of information available at the time of sampling influences the methodology used to create a representative sample.A geometallurgical study of Carpathian Gold’s Rovina Valley Project in Romania is used to demonstrate a sample selection strategy that integrates geological, mineralogical and metallurgical data to maximize the relevance of the geometallurgical unit definitions. This approach, practiced by Xstrata Process Support for its’ clients, ensures that the results of the metallurgical program can be interpreted in the context of these units.INTRODUCTIONGeometallurgy is a cross disciplinary approach in which metallurgical performance of an ore is linked to intrinsic geological and mineralogical characteristics. The objective of a geometallurgical study is to characterize the range of metallurgical performance of an orebody. This allows the geoscientist or metallurgist to create a robust flowsheet able to treat the full range in variability and to develop production strategies to maximize financial performance. The standard approach is to individually sample and test a series of ore types or geometallurgical units. Several different approaches are used in industry to define what constitutes geometallurgical units and how to sample them.One current methodology is the use of multivariate statistics. Geochemical data along with available geological data are used to define multiple variability domains (Williams, 2004; Walters, 2009). There are risks associated with this methodology since the extent of the data set itself may not support a purely statistical approach at the time that metallurgical units need to be defined. The assay suite collected by exploration programs is often limited to pay metals while metallurgical performance is often affected by ore gangue components. Furthermore, in many cases metallurgical scoping and pre-feasibility studies take place prior to the availability of extensive geochemical data sets. Purely statistical methods can produce multiple populations which require extensive sampling, testing and validation prior to consolidation into a reasonable number of composites for metallurgical testing. Methodologies are therefore required that allow representative sampling and testing of consolidated geometallurgical composites to occur at various phases throughout the development of a mining project."

Jan 1, 2013

By Patrick Pelletier Jr., Pierre-Alexandre Bossé, Gianni Bartolacci, Ian Orford, Steve Parent

"Over the last decades, many authors have shown the importance of froth in the flotation process. Mineral recovery is related to froth recovery and flotation. Selectivity is affected by froth characteristics, especially structure and loading. The characteristics of froth textures could therefore be used for diagnosing flotation.Machine imaging, especially image texture analysis, allows on-line measurement of important froth characteristics and process state classification. The measured characteristics include froth texture, loading and stability indicators. To extract information from images, texture analysis tools are used as well as a block-matching algorithm (BMA). For process state classification, images are analyzed with the same tools and clustering is done with multivariate data analysis algorithms.Two case studies, Brunswick Mine Concentrator Cu/Pb circuit and LaRonde Mine Zn circuit, are presented to show that these indicators may be used for diagnosis and control. The influence of manipulated variables on measured froth features is shown as well as the relationship between froth characteristics, mineral recovery and flotation selectivity.INTRODUCTIONImaging is a way to depict abstract characteristics of a scene or an object; it is often related to other types of scientific observations, chemical component concentrations, for example (Geladi and Grahn, 1996). In this paper, the scene is flotation froth. Imaging can be especially useful in applications where it is difficult to obtain the measurements needed for process analysis – froth flotation, for example."

Jan 1, 2006