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By R. Grau

"After commissioning and start-up of the first 500m3 TankCell® flotation cell in 2014, the over 300m3 mechanical flotation cells have earned their place in large-scale flotation operations. These 500 to 630m3 cells, designed for projects with large throughputs, are proven to provide savings in project capital and operational expenditure through savings in foot print, energy consumption, and less equipment to install and maintain. Addition to savings in different phases of a project, these cells provides operational flexibility and has shown improvements in metallurgical performance. In this paper a case study from Kevitsa TankCell® e500 installation and Buenavista del Cobre TankCell® e630 installations will be given.INTRODUCTION After development (Grönstrand and Bourke, 2008), characterization (Morales et al. 2009; Yanez et al. 2009; Grönstrand at al. 2009), validation (Elgueta et al. 2009; Coleman and Dixon, 2010), and more than 350 industrial installations of the Outotec TankCell® e300 flotation cell, the well proven energy efficient TankCell® product family introduced the TankCell® e500 forced-air flotation cell late June 2012 (Outotec.com, 2012). The introduction of the 500 m3 flotation cell followed by introduction of a 630 m3 flotation cell, TankCell® e630, in October 2014 (Outotec.com, 2014). These large flotation cells are designed for projects with high throughputs where the number of cells needed for operation with smaller equipment would become large. The benefits of this size of flotation cells comes from the lower capital expenditures due to lower equipment costs, savings in plant footprint, less installation work with less auxiliary equipment, lower energy consumption, and less units per installation resulting in less components, spare parts and maintenance.The first TankCell® e500 was commissioned and taken into operation in October 2014 at FQML Kevitsa Cu-Ni-PGE concentrator, nowadays owned by New Boliden. The first TankCell e630 was taken into operation in January 2018 at GrupoMexico’s Buenavista del Cobre Cu-Mo concentrator. The start-ups of the first TankCell® e500 and TankCell® e630 followed with test work where the hydrodynamic performances of the cells were characterized and metallurgical performance studied. The results of the TankCell® e500 test work were presented in detail by Mattsson et al (2015a; 2015b) and TankCell® e630 by Grau et al. 2018. In this paper the metallurgical improvements achieved with the large cell installations will be presented."

Jan 1, 2019

"Previous studies on the effect of polytetrafluoroethylene addition during chalcopyrite leaching under conditions similar to those of the CESL process have reportedly resulted in complete leaching of the copper without the need for grinding of the flotation concentrate. However, these studies employed a pulp density of only 1% and finely sized PTFE particle that required the use of high impeller rotation rates that are not sustainable at an industrial scale. This paper explores the performance of 1/8” diameter balls of PTFE, that readily sink in the leach solution, on leaching performance at impeller rotation rates and ore pulp densities more typical of industrial practice. Possible routes for separation of the PTFE from the leach residues and their regeneration for recycling back to the leaching stage are also discussed.INTRODUCTIONChalcopyrite, CuFeS2, is the most important primary sulfide source of copper. While pyrometallurgical smelting of chalcopyrite remains the only widely accepted route for treating chalcopyrite concentrates, several medium temperature pressure oxidation processes are claimed to be economically feasible (Muir & McDonald, 2007). Among these, the CESL process has been extensively piloted and demonstrated at the prototype scale. The overall process chemistry of the CESL process may be summarized as follows (Marsden & Wilmot, 2007):4CuFeS2 + 5O2 + 4H2SO4 ? 4Cu2+ + 4SO4 2- + 2Fe2O3 + 8S0 + 4H2O (1)4CuFeS2 + 17O2 + 2H2SO4 ? 4Cu2+ + 10SO4 2- + 4Fe3+ + 2H2O (2)Though copper extractions of over 95 % are achieved, the CESL process requires extra grinding of the concentrate (Muir & McDonald, 2007). This is because leaching is conducted at temperatures around 150 °C, where the elemental sulfur produced is molten and grows thicker on the mineral’s surfaces as oxidation progresses, creating an increasingly large barrier for mass transport. In addition, the sulfur is sticky and tends to cause the mineral particles to agglomerate, effectively halting further oxidation of the particles that end up embedded within the agglomerates. Consumable surfactants, such as ligin sulfonate, have been shown to be effective at avoiding agglomeration, but they are not effective at removing sulfur from the minerals. Hence, their use does not obviate the need for fine grinding."

Jan 1, 2012

By M. J. S. Innes

Abstract This paper is an account of an investigation made by the Dominion Observatory with a gravity meter and magnetometer over sulphide concentrations at East Sullivan, Val d'Or, Que., in June, 1947. The topographic relief over the area does not exceed 20 feet. The overburden varies from 0 co 50 feet. The west orebody had been outlined by extensive drilling. The average density contrast between the sulphide body and surrounding rocks is 0.5. Two hundred and sixty gravity and one hundred and ninety magnetic stations were observed. The results are shown on contour sketches. A derailed account is given of the methods employed to reduce the gravity observations. The survey shows that both gravimetric and magnetic methods are useful in delineating sulphide deposits under the conditions in which they occur at East Sullivan. The results indicate that the buried contact of the syenite intrusive southeast of the orebody could be traced with the gravimeter and chat the magnetometer was of little value for that purpose. Gravity anomalies due to the varying depths of overburden are negligible as compared to the magnitude of the total anomalies. Introduction The project was first suggested at a meeting of the Associate Committee on Geophysics of the National Research Council in September, 1946. At that time it was pointed out that the accuracy and speed of operation of the new gravity meters made them of special importance for geophysical prospecting and it was highly desirable to have an objective test of the performance of an instrument of this kind in delineating an orebody of known dimensions and density characteristics. Several years ago, a private company did some work with a gravimeter over the Amulet deposits, near Noranda. Unfortunately, the topography there is rather rugged, with hills and ravines exceeding 100 feet, so that the topographical effects rendered it impracticable to distinguish between anomalies due to the sulphides and those due to surface irregularities. An orebody of a typical nature, where the disturbing topographical corrections were not excessive, was therefore sought.

Jan 1, 1949

By Frank B. Amon

Highland Valley Copper had to make some significant changes in the way it was working in order to counter the effects of ever-increasing costs and decreasing metal prices. A mine/mill optimization plan started in 1997 introduced new technologies and management approaches that resulted in a dramatic drop in cash breakeven costs. The changes involved employee training, added authority and responsibility for staff, better communications, and a consistent approach to setting and achieving property-wide goals. The net effect was to change the culture of the organization from one that was fragmented and focussed on local objectives to one that is cohesive and has common goals. These changes have allowed the mine to remain in business during a protracted period of low metal prices, and have positioned the mine favourably to benefit even more from any future increase in prices.

May 1, 2004

By L. D. Haig

"The Texada Mill is a unique iron operation producing High Grade sinter iron concentrate and a by-product copper, gold, silver concentrate. The plant is complex and extremely flexible to handle the many varieties of ore. Two iron concentrates are made and blended. A coarse iron concentrate from primary grinding and a fine concentrate after rougher flotation to remove all the sulphides.All the tailings from iron processing are collected, dewatered, reground and floated for additional copper recovery.The entire milling operation has been carried out in all sea water for seven years and mixtures of sea, fresh, and reclaimed water for ten years prior to that.A very stable float results from the use of sea water at the natural pH8. Reagent Consumption is lower and Metallic Corrosion of mill liners and grinding media is actually less than local fresh water or mixtures of fresh and sea water.Marine growth in pipe lines can be periodically removed by violently bubbling high pressure air up through the water filled mains.Location:Texada Mines is located on tide water on the west side of Texada Island 100 miles northwest of Vancouver, B. C.The Island is served by a 30 car ferry, tug and barge and a scheduled air service from Vancouver to a company maintained air strip near the mine.The climate is moderate with about 30 inches of rain during the winter and relatively dry summers."

Jan 1, 1974

By Roberto Busato Belger

- Fertilizer Business Overview - Supply -Demand Balance in the World - Supply -Demand Balance in Brazil - Brazilian Market Growth Opportunities - Fosfertil Operations - Fosfertil Expansion Plan - Salitre Project - Project Characteristics - Technical Challenges and Solutions - Technical Support Studies Conclusions

May 1, 2010

By Edouard Asselin, Tasawar Javed

The precipitation of hematite from ferric sulphate - cupric sulphate - lithium chloride acidic solutions was studied in a batch reactor. The effect of several variables on the extent of hematite precipitation as well as on its crystallinity and purity was investigated. The variables studied include: initial ferric concentration (1.5 - 30 g/L), retention time (0 - 12 h), initial sulphuric acid concentration (0 - 30 g/L), temperature (150 - 220 °C) and chloride concentration (0 - 25 g/L). The results show that hematite is preferentially precipitated at lower initial iron concentrations. Longer retention times increased the fraction of hematite in the precipitates but did not affect its crystallinity to a significant extent. On the other hand, higher temperatures increased the purity and crystallinity of the hematite. At lower acid concentrations hematite and goethite were precipitated. However, only hematite was precipitated when the initial acid concentration was > 12.5 g/L. Better crystalline hematite was formed at lower acidities. Increasing chloride concentration increased the amount of hematite and decreased the amount of iron sulphate hydroxide phases, but did not affect the crystallinity of the hematite.

Jan 1, 2015

By Xuanxue Mo, Zengqian Hou

"Abstract -Yidun Island Arc in Sanjiang Region is one of the important Kuroko-type volcano­ genic massive sulfide deposits (VMS) districts in southwestern China. Tectonically, the region is situated in the eastern portion of the Tethys orogenic belt, and is a late Triassic extensional island-arc. The island-arc underwent earlier arc construction, intra-arc rifting, later arc construction and back­ arc spreading during its evolution and formed a complete trench-arc-basin system, i.e., the Ganzi­ Litang suture zone, forearc basin, outer arc, intra-arc rifting zone, inner arc and back-arc basin from east to west across the island-arc.Kuroko-type VMS deposits and occurrences discovered so far are limited to within the intra-arc rifting zone of the Yidun Island Arc and tend to occur in groups or clusters distributed in separate fault­ bound basins; e.g., Zengke, Gacun and Xiangcheng basins, in which submarine volcanic rocks, especially bimodal volcanic suites, were extensively developed. The VMS deposits formed in the waning stages of volcanic eruption in the late Triassic and are hosted in the uppermost section of acidic volcanic rocks (rhyolitic-dacitic) within a bimodal suite. The orebodies are associated with these host rocks: rhyolitic-dacitic pyroclastic rocks and exhalites and chemical sedimentary rocks.Ali VMS deposits in Sanjiang are of the Zn-Pb-Cu type. The architecture of the deposits is two­fold, consisting of concordant lenses and layers of massive sulfides and an underlying discordant stockwork. Ali deposits show metal zoning. The hydrothermal alteration related to mineralization is strong and asyrnmetrical, and is found dominantly within the stockwork zone and host rocks surrounding the ores. There are two alteration patterns: (1) chloritization - sericitization - silicification from outer sides to core of the alteration pipe; and (2) silicification + sericitization - silicification + carbonate from the lower to upper part of the alteration pipe_The mineralization temperatures of ore-forming fluids vary in the range 200°C to 335°C. Thermal evolution of the fluids displays temperature profiles that first increase and then decrease with progression of mineralization processes. The majority of black-ore minerais (Groups I and II) formed during intensifying stages of hydrothermal activity, and the majority of serni-yellow-ore minerals (Group III) formed during a thermal maximum . There followed the formation of fine-grained black-ore minerals (Group IV), which interacted with barite layers during decreasing temperature phases.Oxygen and hydrogen isotope studies show that the sources of ore-forming fluids for the Kuroko­ type VMS deposits are two-fold: seawater and magmatic hydrothermal solutions, represented by the Kuroko deposits in Japan and Kuroko-type VMS deposits in Sanjiang, respectively. In the latter case the hydrothermal solutions reacted with host rocks and mixed with cold seawater percolating downward, and circulated through volcanic rocks resulting in development of alteration zones and formation of ore minerals in Kuroko-type VMS deposits."

Jan 1, 1993

By F. Rosenblum, P. Spira

"Techniques were developed to determine the oxygen demand of sulphide ore pulps in the laboratory and in concentrators. The effect of variables which influence oxygen demand was studied, and it is shown that the oxygen demand is a measure of the degree of oxidation of the sulphide surfaces. It is suggested that in investigating the significance of oxygen in flotation, the oxygen demand of the pulp is a more suitable parameter than the dissolved oxygen content.Oxygen demand measurements are being carried out with a view to determining the effect of aeration on mill metallurgy and devising improved methods of predicting aeration requirements of sulphide ores.The importance of pulp oxidation in the flotation of massive sulphide ores has long been recognized. At the Noranda concentrator, chalcopyrite could not be floated satisfactorily without a pre-flotation aeration step because the necessary dissolved oxygen was consumed by the large amount of pyrrhotite in the ore. With aeration, pyrrhotite and pyrite were depressed by surface •oxidization, and the resulting thiosulphate level in solution gave a good indication of the end of useful aeration. 1'he present study was prompted by the need to find an alternative criterion for cases where recycled mill water may contain a relatively high concentration of thiosulphate. Preliminary experiments suggested that the rate of oxygen uptake by the pulp -its oxygen demand -might be a practical measure of the end point of aeration as well as a significant parameter in the flotation of massive sulphide ores.Although it has long been realized that oxygen is an important variable in flotation, analytical difficulties precluded detailed plant investigations. Measurements of' dissolved oxygen in mill pulps were first reported by Ralston(i) in 1929. A titration method was used, and because of the delay occasioned by the preparation of clear solution samples, the values obtained were believed to be low. It was quite evident, however, that pulps in the grinding circuit had a lower oxygen content than in flotation. More recently, Woodcock(2,3) used a polarographic probe to carry out oxygen surveys in six Australian concentrators and he generally observed a similar pattern. A large number of other solution parameters were monitored, such as pH, redox potential, reducing power, and reagent and metal concentrations, with the aim of detecting correlations among the measured variables. A few potentin.lly useful relationships were found ""or specific operations in certain plants."

Jan 1, 1974

By P. Walford, C. Mealin, D. Good

"The geology of the Ore Fault Ni-Cu deposit has been reinterpreted in the light of recent studies of the geology of the Neoarchean Bird River Sill Complex and the occurrence of economic Ni-Cu and Zn-Cu-Ag mineralization. The Ni-Cu sulfides are hosted by the lower of two parallel NNW-trending and moderately W-dipping mafic-ultramafic intrusions related to the Bird River Sill Complex. The bod¬ies intruded a bimodal volcanic suite consisting of weakly deformed mafic flows and felsic pyroclastic rocks. The mafic volcanic rocks are geochemically related to the MORB-type rocks of the Lamprey Falls Formation, and the felsic volcanic rocks are related to arc-type rocks of the Peterson Creek Formation. The original pyroxene- and olivine-dominated mineralogy of the sills has been replaced by variable ser¬pentine-amphibole-talc-carbonate assemblages.The Ni-Cu sulfide assemblage exhibits textures and geochemical signatures typical of orthomagmatic sulfide mineralization. The sulfide minerals are associated with cumulate layers of magnetic ferrochromite that range in thickness from a few to tens of centimeters. A later event of Zn-Cu-Ag sulfide mineralization associated with quartz veining and garnet-chlorite alteration along a fault that strikes north, dips vertically, and cuts all rock types. The mineralized fault is cut by the NE-trending Peterson Creek shear zone. Where the Ni-Cu and Zn-Cu-Ag mineralized zones intersect, remnant magmatic features such as amphibolite or cumulate ferrochromite bands occur within quartz veins or local chlorite alteration. The mixed zones contain a very unusual polymetallic assemblage of Ni, Cu, Zn, Ag, and platinum group elements (PGE)."

Jan 1, 2009

By N Berkowitz

Slurry pipelining, as now under-stood and practised, can only command marginal interest in Canada, as long-distance railway freight charges in this country are generally lower than slurry pipeline tariffs. Several alternatives to conventional slurry transmission are, however, now emerging, and two such alternatives are briefly discussed with reference to coal pipelining. In one, coal is transported as a suspension in oil; the other contemplates the movement of paste "slugs." Preliminary economic estimates indicate that the resulant process simplification and adoption of common carrier principles could lead to cost reductions that might make Western coal competitive with imported fuel in the power generating stations of eastern Canada. R ECENT appraisals of slurry pipelining techniques, some-what incongruously 'based upon the performance of successful installations (1,2), are making it increasingly apparent that current solids pipelining methods can only command marginal interest as methods of bulk commodity transportation (3). Although some uncertainties remain in matters of detail, it is now generally conceded that long-distance slurry pipelining cannot compete against rationalized railway transportation unless movement of

Jan 1, 1963

The rock mass classification systems were developed for different functions, including support selection, excavation method selection and the determination of rock mass engineering properties for excavation design, among others. This explains in part why we have several rock mass classification systems. It is often cautioned that the rock mass classifications are to be used for preliminary excavation support design, but this caution is now often overlooked and detail/final support design based on the rock mass classification systems. This paper advocates differentiating between rock mass classification for pre-excavation support planning and rock mass classification for at-face excavation performance assessment. It is concluded that most at-face excavation performance problems are attributable to confusing the virgin rock mass rating with the rock mass rating on exposure during excavation, and that this observation is independent of the method of excavation. Procedures are then presented for virgin rock mass rating and for at-face rock mass rating/assessment during excavation.

May 1, 2009

By C. R. Edwards, J. R. Smith

"INTRODUCTIONThe purpose of this paper is to give an overview of the ALSANDS PROJECT, with emphasis on the approach taken in the design of the Primary Extraction and Froth Treatment Plants.The Alsands Consortium (Table 1) is a Joint Venture of 9 companies formed in 1978, with its prime objective to obtain governmental approval and concomitant suitable commercial terms to build and operate a third oil sands mining and upgrading facility in the Athabasca Oil Sands Deposit.Alsands Energy Limited is the Consortium Manager.The Alsands Project will provide about 10 percent of Canada's forecast crude oil production by 1990, which will be 20,700 cubic metres per day (130,000 barrels/day) of synthetic crude oil plus 1,100 cubic metres per day (7,000 barrels/day) of liquid petroleum gases. To construct Alsands the time required by construction labour, field non-manual and engineering support personnel as well as those trades involved in project-related urban development will total approximately 100,000,000 manhours or 50,000 man years. During regular operations, 4,800 people will be employed by Alsands.Approximately $13 billion will be spent to design, construct and start up the plant by the scheduled 1988 completion date."

Jan 1, 1982

By Faan Bornman

"Reeves and Platt1 stated that dense medium separation is one of the most complex unit processes in mineral processing today particularly if cyclones are used. It is also the most efficient gravity concentrating process available to process engineers. The complexity of the process and large number of design and operating variables means that the process has largely remained more an art than a science. Dense medium separation is well established in the diamond, coal and iron ore industries but is gaining popularity as a pre-concentration step in other industries. The maintenance issues are addressed that will affect the efficiency of the operation.INTRODUCTION The purpose of the dense medium separation (DMS) process is to separate the valuable material from the waste based on gravity differences. However, the specific gravity difference between the two fractions must be large enough to achieve high efficiencies. Heavy particles sink through the dense liquid and light particles float. DMS is also used for the pre-concentration of minerals before further downstream processes like communition, in order to minimise the treatment costs. Examples are the pre-concentration of diamond ores or metalliferous ores like nickel, copper and cobalt. Dense medium separation is also used to upgrade the material to meet different market specifications, for example in coal and iron ore applications. A typical dense medium separation process for a diamond application is shown in Figure 1."

Jan 1, 2014

By Bin Tang, Suping Yao

In the last decade, the copper industry in China has developed rapidly and attracted the world’s attention. The production capacity of refined copper has grown remarkably from 4.578 million tons in 2010 up to 9.029 million tons in 2018, accounting for about 40% of the global refined copper production. And now, China has become the biggest refined copper producer in the world. This paper summarizes the application of modern copper metallurgical technologies such as Outotec flash smelting/converting technology, Cyclone smelting technology, TSL (ISA/Ausmelt) smelting/converting technology, Jinfeng side blown smelting and Baiyin side blown smelting technology, Chifeng side blown smelting and continuous top blown converting technology, SKS bottom blowing technology, Dongying two-step smelting technology, copper electrorefining with high current density, etc. in China’s copper industry, analyzes and compares the characteristics of those technologies and presents the great efforts of China’s copper smelters in adapting to the increasingly strict emission standards and improving economic benefits of copper smelters. INTRODUCTION China has been the biggest refined copper producer in the world for many years. China produced million tons of refined copper in 2018, accounting for 40% of the copper smelting production in the world, and of which, roughly, 70% of the copper concentrate was imported, mainly from Chile, Peru and Australia. ICSG (International Copper Study Group, 2017) shows clearly the position of top 20 countries of copper production and copper mine production (Figures 1 and 2). Blast Furnaces, Reverb Furnaces and Electric Furnaces dominated China Copper Smelting for quite long time till 1980s. The first modern copper smelting technology (flash copper smelting) was introduced into China in 1980s, then followed by Noranda, Ausmelt and ISA. Since then, China copper smelting technology stepped into modern time. Since 2000, old processes (Blast Furnace, Reverb Furnaces and Electric Furnaces) were phased out and replaced by modern smelting technologies. China Copper Production has been increasing dramatically (Figure 3).

Jan 1, 2019

By François Robert

"The Eastern Abitibi Sub province (Quebec segment), contains two main types of gold deposits: the common quartz-vein type and the rare pyritic type. Both occur in areas dominated by volcanic rocks and are spatially associated with major fault zones.Quartz-vein gold deposits consist of simple to complex networks of quartz-carbonate-pyrite veins in reverse shear zones and extensional fractures. They occur in areas dominated by mafic volcanic rocks and are commonly associated with small syn- to late-tectonic porphyritic felsic intrusions. Associated alteration, which postdates peak metamorphism, is dominated by carbonatization, sericitization and pyritization of the wallrocks. These deposits formed late in the geologicalevolution of the Abitibi.Pyritic gold deposits range from deformed massive sulphide lenses to zones of syntectonic pyrite-rich veinlets and associated pyrite disseminations. These deposits occur in environments dominated by felsic volcanic rocks that are typically converted to sericite schists near the deposits. The associated pre-metamorphic aluminous alteration is now characterized by metamorphic sericite, andalusite, kyanite and chloritoid, overprinted by a late retrogression of alumino- silicates. These deposits probably represent deformed volcanogenic massive sulphide deposits, but the timing of gold introduction in these is not fully understood.The differences in geological attributes reflect significant differences in the genesis these deposits: the pyritic deposits probably have a multistage genesis, including a pre-tectonic stage, in contrast to a single stage late-tectonic genesis for the quartz-vein deposits.RESUMELa partie Est de la Sous-Province de l’Abitibi( segment québécois) renferme deux types de gites d' or: ceux de type ""veine de quartz"" et ceux, plus rares, de type ""pyriteux"". Ces deux types se trouvent dans des secteurs particulièrement riches en roches volcaniques et mantrent une association spatiale avec des zones de failles majeures.Les gites de type ""veine de quartz"" correspondent à des réseaux de complexité variable de veines de quartz-carbonate-pyrite se développant dans des zones de cisaillement inverse et des fractures de tension. Ils se concentrent dans les régions dominées par des roches volcaniques mafiques et s’associent fréquemment à de petites intrusions porphyriques felsiques syn- a tardi-tectoniques. L’altération associée ace type de glte est postérieure à la phase majeure du métamorphisme et consiste en une carbonatisation, une sericitisation et une pyritisation des épontes. La mise en place de ces gites est tardive par rapport à l'évolution géologique de l'Abitibi.Les gites d' or de type pyriteux consistent en des lentilles de sulfures massifs déformes, des zones d' abondantes veinules pyrite uses syntectoniques, et des zones de pyrite disséminée. Ces gites se retrouvent dans des empilements contenant surtout des roches volcaniques felsiques qui sont transformées en schiste à séricine pres des gisements. L’altération a l’umineuse pre-metamorphique associée a ce type de glte a donné naissance, lors du metamorphisme regional, a la sericite, a 'andal ousite, a Ia lcyanite et au chloritoi""de; par la suite, les alumino-silicates ont été affectes par une alteration retrograde tardive. Ces gites representent probablement des depOts de sulfures massifs volcan gènes déformes, mais la chronologie de la mise en place de l'or dans ceux-ci est encore mal comprise.Les caractéristiques géologiques propres à chacun de ces types de gites reflètent des conditions de formation différentes: le type ""pyriteux"" montre une histoire génétique polyphasée, incluant une étape pre-tectonique alors que le type ""veine de quartz"" s’est développe au cours d’une seule phase tardi-tectonique."

Jan 1, 1990

By Y. Thibault, G. Deschênes

An open-pit mine, located in Mexico, processes an ore a rate of 4000 tpd, using conventional cyanidation and AYR. A laboratory study was conducted to increase silver extraction and to reduce the concentration of cyanide in leaching. The sample contained 0.41 g/t Au, 125 g/t Ag, 99% gangue minerals, 0.7% pyrite, 0.07% sphalerite, 0.03% chalcocite. Silver was present as acanthite, stromeyerite, silver mercury/halogen, silver with copper in solid solution and jalpaite. The plant conditions (2400 ppm NaCN) produced 90.2% gold extraction (residue at 0.04 g/t Au) and 92.7% silver extraction (leach residue at 9.1 g/t Ag). The CELP (CANMET Enhanced Leaching Process) produced 97.0% silver extraction (residue at 3.8 g/t) and 90.2% gold extraction using 500 ppm NaCN. The incremental gross revenue was estimated at $US7.6 million and the reduction of cyanide costs was $2.9 million per year (79%).

Jan 1, 2011

By K. E. Barnes

"The “Jameson Cell” flotation cell was developed at Mount Isa Mines in the late 1980’s to address deficiencies in our flotation column installations. Early base metal installations had a variable record. The test work and trials showed they made an improvement metallurgically when operated correctly, but performance of the early installations was hindered by a range of operational and maintenance issues. The installations needed to be more robust, and we needed a better understanding of how to successfully integrate the cells into the plant flow sheet.During the 1990’s, Jameson Cells had great success in coal fines flotation and organic removal in SXEW applications, and became the standard in these applications in Australia. These installations improved the cell design and materials of construction and the cell flow sheet design, to make it low wear with self-regulating control, producing good performance with little operator input.These improvements have enabled a fresh look at the use of Jameson Cells in base metals. Recent new installations have shown significant benefits in “hybrid” circuits, that combine the best features of both Jameson Cells and conventional flotation cells, achieving better overall circuit performance in a smaller footprint than either technology could do by itself.Case studies of successful base metal applications are discussed, using size-by-size mineralogical performance to explain the improved circuit performance. The new methods of flow sheet test work design are also described."

Jan 1, 2006

By W. Haibei, Lei. Z., Z. Bangsheng, W. Yufang, J. Kaixi

In 2007 output of zinc was more than 3.71 million tons in China. Some new projects have finished FS and several new zinc plants are building now. In recent ten years it happened great changes in zinc industry. For zinc concentrates one pressure leaching plant was built with capacity 10,000t/a and at least four companies are carrying out FS or engineering design now. Direct atmospheric leaching will put into used in China in 2008 with capacity 100,000t/a. It is estimated that until 2010 the output of direct leaching will be 400,000t/a.

Jan 1, 2008

By S. McCalpine, W. Muir, P. J. Downey

"Golden Bear Operating Company Ltd. (GBOC) was a joint venture between Chevron Minerals Ltd. and North American Metals Corp. that was formed for the development of the Golden Bear Project. The mine is located at Muddy Lake, Western British Columbia, approximately 80 km northwest of Telegraph Creek and 135 km west of Dease Lake (see Figure 1). Road access to the mine was developed by Golden Bear and consists of a radio controlled 155 km gravel road originating at highway 114.A feasibility study was completed in 1987 and project approval was finalized in 1988 with Golden Bear issuing a ""Request For Proposal"" for detailed engineering in May 1988. Golden Bear also commenced negotiating with vendors at this time for the supply of the two principal process equipment packages: the dry grinding and classification system and the whole ore roaster package.Process plant engineering and plant construction was completed in October 1989 with plant startup commencing in November 1989. Two months into the commissioning phase it became apparent that the plant, as designed, would not achieve the anticipated production targets.Kilborn Engineering Pacific were subsequently contracted by GBOC to review and modify the plant design, assist the operating personnel with plant commissioning and startup and provide operator training.This Paper describes some of the problems encountered during the startup and the plant modifications incorporated to achieve design parameters."

Jan 1, 1992