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By Roger Moss

OUTLINE Area selection Mineralization/Alteration Styles Island Copper Mineralization Geophysics Geochemistry Coppercorp Setting Mineralization Geophysics Geochemistry Formation Common Characteristics Conclusions

Apr 1, 2005

By Gerhard Melcher, Hermann Hilbrans, Michael Gamroth

"IntroductionSeveral new smelting processes have been proposed and developed during the last 20 years. This has been true, in particular, for copper smelting technology. The important impulses for the advances in this field have been the recent demands regarding the environmental protection, energy saving and improved utilization of the metals contents of deposits, in particular that of complex raw materials.The methods developed more recently for pursuing these objectives have been outlined in several papers. In some of them the advantages and drawbacks of certain developments have been stressed. These documents are of great importance for assessing the different processes. The following paper tries to explain some details of the cyclone smelting process taking into consideration a few of these well-known presentations. The effectiveness of operation of the cyclone smelting process indicates that this process presents a significant achievement when compared with other conventional methods.The application of the CONTOP smelting cyclone range s beyond the field of copper metallurgy or the smelting of sulphide concentrates with the aid of oxygen. The research work carried out in the pilot plant of KHD Humboldt Wedag AG in Cologne-Porz also includes the recovery of the metal contents of intermediate products and processing of smelter residues which have to be converted in a disposable stat e, free of environmental pollution. This paper explains a few examples in this regard."

Jan 1, 1987

By G. Herget

"A brief visit to European longwall mining operations in potash showed that retreating longwall mining provides a very attractive alternative to room-and pillar mining, especially in areas with bad roof, narrow seams and areas with high ground pressures. Mines de Potasse d'Alsace, France converted all potash operations to longwall mining in 1980. Recovery rates per panel vary between 75o/~ to 85% which compares very favourably with Saskatchewan values. Ground pressure in Saskatchewan are comparable to those of some of the deposits in Europe, but the presence of water in the hanging wall of Saskatchewan orebodies has to be given serious consideration. However, given the mining experience in Saskatchewan and the improved technology f or laboratory and field investigations, a review of present mining practice in Saskatchewan is desirable. IntroductionLongwall mining is practiced widely in coal mining and allows complete mechanization. It is applicable at great mining depth, in thin seams, weak roof and has been applied recently even to coal bed s dipping more than 65 degrees. Ideally this system allows complete extraction of an orebody. However, with high mechanization and emphasis on obtaining high outputs per man shift, extraction ratios rarely reach more than 80010 per panel.France, Spain and the U.S.S.R. have had longwall operations in potash for some time and a brief description is given below. Two of the operations were visited and the Russian operation is described based on German literature"

Jan 1, 1986

By J. E. Danoczi

Shore Gold Inc. (Shore) is presently designing a diamond processing plant for the Star and the Orion South kimberlite deposits in the Fort à la Corne area kimberlite field in central Saskatchewan. The first step in the plant is diamond liberation and occurs in the comminution section. Diamond liberation is the process of breaking up the kimberlite rock, as ?gently? as possible since essential to the diamond liberation process is the minimization of diamond damage, particularly for the larger, high value diamonds. The Southern African diamond mines traditionally use Jaw and Gyratory crushers as their primary comminution method. However, these diamond mines generally process the harder, competent kimberlite that is located in the diatreme zone as well as the root zone of the volcanic pipe. Softer kimberlite is typically located in and around the crater area of a volcanic pipe and it is this source of kimberlite that makes up the majority of kimberlite for both the Star and Orion South deposits. These softer kimberlites can be readily broken up using abrasion and attrition imparted by AG mills, this being the preferred method of comminution for minimizing diamond damage.

Nov 1, 2011

By T. S. Grewal, S. C. Gupta, H. Natarajan, T. W. McQuade, N. Nejibulloev-Mamedov

Cigar Lake is one of the world’s largest high-grade uranium mines. The ore mined at Cigar Lake is milled at Orano Canada Inc’s (Orano) McClean Lake mill. The average Cigar Lake ore uranium grade since the start of mining activities in 2014 is 17.8% U (range 8– 28%). To achieve budgeted production of 18 M lbs U3O8/yr the required average feed tonnage to the mill is about 45 kt/yr. Arsenic, occurring as arsenides and sulpharsenides, is one of the major elements of concern associated with Cigar Lake ore. The leaching process is a sulphuric acid leach under oxidizing conditions at near atmospheric pressure. The presence of arsenic in the ore consumes oxidant in leaching as well as ferric sulphate in tailings preparation for arsenic sequestration. The average arsenic grade since the start of mining at Cigar Lake is 0.57% As. Further, the ore is hosted in a matrix of sandstone and clay, which results in poor settling in CCD. The average uranium grade for the balance of Cigar Lake Phase 1 ore is expected to drop to 12.5% U and the average arsenic grade is expected to increase to 1.6 % As, with an annual average peak of 2.5%. Therefore the tonnage throughput required to sustainably meet the production target will increase to 55 kt per year. Orano partnered with Hatch Ltd. (Hatch) to perform a gap analysis study to identify key circuits and equipment in the mill that would require debottlenecking. A METSIM mass balance model of the McClean Lake mill was generated and validated with actual mill operating data. Various feed scenarios were then studied, and the outcome was a traffic light table, which highlighted feed scenarios that exceeded installed capacity of major equipment and circuits. The results provided the basis for the PDC for the pre-feasibility study. This paper will outline the results of the gap analysis, the mass balance model, the feed scenarios and the study undertaken to prepare the McClean Lake mill for the change in ore quality from Cigar Lake.

Jan 1, 2020

By Göckmann. Klau

"IntroductionCopper has been recycled ever since its discovery. Even in Graeco-Roman times recycling of this resistant, and thus valuable material was carried out as a matter of course. Just take, as an early example, the Colossus of Rhodes: after the figure collapsed during an earthquake, the bronze parts were melted down into ingots and sold.Copper is a material which can be recycled again and again because copper produced from recycling is not different from copper originating from primary materials. This is mainly due to electrolytical copper refining whereby not only the base metals but also the precious metals can be removed. In contrast, with aluminum and iron only the more electropositive elements can be removed by refining, and the resultant scrap must, therefore, be sorted mechanically into various alloys for subsequent smelting.The recycling rate for different base metals is given in Table 1. Despite this ideal prerequisite, the generally quoted recycling rate of copper of about 40070 appears rather low. However, it must not be forgotten that the recycling rate is defined as the ratio of the annually utilized quantities of copper scrap and the annual production figures (Table 2). Moreover due to the economic growth over the last 30 years the availability of copper from scrap materials is lower than its consumption because copper is principally employed in very long-life consumer durables and only returns to the recycling circuit after many years. The average time for the copper of some goods to be recycled is detailed in Figure 1."

Jan 1, 1992

By A. Haldar

This study focuses on the flow characteristics of hypereutectic Al-Si alloys in thin sections. The pattern assembly consisted of spiral horizontal patterns, 6.25 mm (0.25 inch) and 12.50 mm (0.50 inch) in thickness with a common sprue. Al-Si alloys with silicon levels of 14%, 18% and 22% were poured with superheats of 60°C, 115°C and 170°C. It was observed that metal fluidity (in terms of flow length and metal velocity) increased with increase in silicon levels and superheat for both section thicknesses. It was also observed that, for a section thickness of 6.25 mm (0.25 inch), silicon level had more pronounced effect on the metal fluidity. For 12.50 mm (0.50 inch) thickness, both silicon level and superheat affected the metal fluidity. The surface hardness of the castings increased with an increase in silicon level of the alloys at the gate and the flow tip. Detailed study of the flow tip was also carried out with a view to understanding the effect of silicon level and superheat on undulated flow length, surface hardness and microstructure.

Jan 1, 2007

By R. Harrisson, K. Esmaieli

Brunswick mine employs an ore and waste pass system for material transfer. This paper reviews the evolution and performance of ore pass systems at the mine. It presents the range of selected configurations, inclination, dimensions, etc. Select case studies are used to address the influence of structure, stress and materials handling on the longevity of the employed ore passes.

Jan 1, 2008

By S. C. Cohen, A. F. Mikkelsen

"This paper describes the improvements made to the operation of a liquid phase, 300°C, heat transfer system in the paste plant of an aluminum smelter. These improvements were achieved by replacing the original heat transfer fluid, a synthetic aromatic, with a new technology, petroleum-based product. This new fluid, Calflo HTF, provided better thermal stability, with lower toxicity, and improved plant working conditions.The procedures for fluid selection, changeout and performance monitoring are described along with a summary of control analysis over the last three years."

Jan 1, 1993

By D. V. Krefting, D. R. Bennett

"The Cyprus Anvil Mining Corporation established a lead-zinc mine and concentrating plant at Faro in Yukon Territory in 1969. Following some 12 years of continuous operation from a single pit adjacent to the concentrator, the company decided to expand operations into two additional areas on the Vangorda Plateau. The two new deposits, known as Grum and Vangorda, are located some 15 kilometres from the existing concentrator.Confirmation of mining feasibility was followed by determination of the most practical and economical method of transporting the raw ore from the new mine sites to the existing concentrator. This analysis was carried out in two phases. The first phase reviewed the feasibility of alternative transportation systems on an 'order-of-magnitude' cost basis. This work identified systems worthy of more detailed examination. The second phase examined the preferred alternatives in greater detail.Initially, operating principles and parameters were established and catalogued. Then, based on these criteria, complete systems were developed utilizing alternative modes of transportation . In the overview analysis, some transportation modes were judged impractical and discarded, 'order-o f-magnitude' costs were developed for other systems and the most costly were eliminated . In the detailed study, the favourable systems were examined in depth which required development of accurate capital and operating costs, consideration of environ- mental impacts and an assessment of intangibles associated with the operation of a new development."

Jan 1, 1984

By S. Dallaire

With the attainment of high temperatures it becomes possible to process any kind of material (particularly ceramics) in their liquid state. In the plasma spraying process, the material to be sprayed is rapidly heated until it is molten and is propelled by high velocity gases onto a surface where it adheres, to give protective coatings for a wide range of applications. The method could be considered as one of the most versatile and rapid to build up thick deposits (of plastics, metals, ceramics, cermets) and also free-standing artifacts for particular requirements without resorting to lengthy forming and sintering studies. Although plasma spraying is at the production stage in industry, advanced processes have also been developed for economically producing a wide range of new materials. This paper illustrates the benefits of the process and evaluates the challenges it represents.

Jan 1, 1987

By E. G. Parker

"Sherritt's zinc pressure leaching process converts zinc sulphide concentrates directly to zinc sulphate solutions and elemental sulphur. Thus, one pressure process step replaces both the roasting and leaching operations of the conventional roast-leach route. In addition, high single-pass extractions eliminate the need for residue treatments to recover unleached zinc. Because pressure leaching produces elemental sulphur, rather than sulphur dioxide, acid plants and smoke stacks are not required, and air pollution control and work-place hygiene are greatly improved. .In 1977, Cominco Ltd. and Sherritt Gordon Mines Limited jointly operated a three-tonne-per-day pilot plant to demonstrate pressure oxidative leaching of Sullivan zinc concentrate and the subsequent separation of elemental sulphur. The process consisted of regrinding the concentrate, continuous leaching at 150°C at elevated oxygen pressures in a four compartment autoclave and the subsequent recovery of elemental sulphur, either in the molten liquid form from a decantation autoclave or as a flotation concentrate. Of the zinc contained in the concentrate, 97% was extracted in 90 minutes, and 96% of the sulphur was converted to the elemental form.Following the successful pilot campaign, Cominco began building the world's first commercial zinc pressure leaching plant. This plant, which was in operation by late 1980, will eventually treat about 25% of Cominco's planned zinc capacity of270,000 tonnes per year.This paper describes the general process principles, the results obtained from the pilot plant and the integration of the process into Cominco's operations at Trail. The application of pressure leaching to a ""grass-roots"" plant is also discussed, and compared with conventional roast-leaching."

Jan 1, 1981

By Nigel J. Cook

"Detailed mineralogical examination of gold-bearing rocks, ores, concentrates and other samples should be considered an integral part of any study of a deposit for which exploitation is being planned. Adequate mineralogical study, although time consuming and often costly, can significantly improve understanding of the mineralization, can help to optimize the results of any metallurgical testing and can be of great value in case of potential trouble-shooting. The advantages and disadvantages of various examination techniques are discussed with reference to a number oj mineralogical studies oj Canadian gold-bearing samples.IntroductionVarious authors, notably Gasparrini (1983), Harris (1989) and Henley (1990), have stressed that mineralogical study of gold ores is critical to successful and efficient beneficiation. Only in cases where diagnostic cyanide leach testing is successful can detailed mineralogical examination be disregarded. Such examination of gold-bearing rocks and metallurgical products is all too often neglected because the methods involved are believed to be time-consuming, costly, and may carry a considerable degree of inaccuracy. Commonly, bulk metallurgical testing is, carried out without prior or concurrent mineralogical examination, causing the results of the testwork to be difficult to interpret, or in some cases, misleading. This, in turn, may lead to> significant delays to the project at the feasibility stage or mean that understanding of the sample is limited, preventing the introduction of prudent modifications at a later stage if problems arise. Mineralogical studies may guide the successful implementation of a metallurgical test program."

Jan 1, 1990

By John E. Udd

"In this paper the author presents the results of the 1992 CIM survey of graduates in minerals and technology programs in Canadian post-secondary institutions. As usual, the trends are out-of phase with the economic state of the industry. People who chose a minerals career in the prosperous days of the late 1980sare now entering a labour market in recession.The cyclical nature of enrollments is illustrated in a series of figures showing the trends since the CIM survey Wa5 begun in 1956 (and even earlier for mining engineering).In the survey, the respondents were asked to provide comments on their perceptions of the problems specific to minerals education in Canada. The large number of responses have led the author to the conclusions and recommendations given in the final part of the paper."

Jan 1, 1993

By Bill Dupley

We believe that the inability of employees to effectively manage information has reached an epidemic problem throughout the corporate world. ? All the available knowledge in the world is accelerating at a phenomenal rate. ? The whole world's codified knowledge base (all historical information in library books and electronic files) doubled every 30 years in the early 20th century. ? By the 1970s, the world's knowledge base doubled every seven years. ? Information researchers predict that by the year 2010, all the world's codified knowledge will double every 11 hours.

May 1, 2003

By R. Mariano

"The ability to optimise a concentrator from mill feed to final products requires a process simulator that integrates comminution, classification and separation stages. A key part of any such integrated process simulator is the inclusion of a model of mineral liberation in comminution to predict the particle composition distribution of the comminution products. This need was recognised by Gaudin (1939) who proposed a model of liberation based on the cubic fracture of a mineral texture composed of cubic grains of two minerals.This paper describes the development of a texture-based model of mineral liberation that builds on the method proposed by Gaudin. The approach described here, termed the JK-Gaudin Random Liberation model (JK-GRLM) uses as its basis the measured, volumetric mineral texture data that can be quantified for a given ore using X-ray micro-tomography. The textural data required as inputs for the JK-GRLM include the mineral grain size distribution. While the Gaudin model (in common with other existing liberation models) is a two-mineral (or two-phase) system, the JK-GRLM extends the approach to multimineral systems of up to 15 individual minerals, making it more widely applicable.An example of the application of the JK-GRLM to a base metal sulphide ore is provided. In the example the JK-GRLM is used to simulate the breakage of the measured ore texture and the particle composition distributions of the simulated progeny particles are compared to the measured particle composition distributions of ore that has been physically broken.The ability to calibrate this mineral liberation model with measured ore texture will allow it to be applied in greenfield situations where geometallurgical programs measure texture and in brownfield applications as a key part of integrated process simulations. The development of this model enhances our ability to simulate mineral processing operations as an integrated system."

Jan 1, 2016

By J. G. Conaway, P. G. Killeen

"Gamma-ray spectral logging, a useful technique for uranium exploration and evaluation, has generally been underutilized by the Canadian mining industry. Provided that the technique is properly applied, it is capable of yielding reliable quantitative information regarding the distribution of uranium and other radioelements along the borehole under most conditions.In practice. there are numerous factors which potentially can degrade the quality of the log and thus any quantitative interpretation based on it. Fortunately, the appropriate choice of logging equipment and technique can avoid many such problems, and corrections can be applied to the data to compensate for most of the others."

Jan 1, 1980

By J. Talja

"Non-ferrous metal concentrates contain typically 7 – 12% water when received at the smelter. Removal of this water prior to smelting is always economically feasible because unnecessary heating of vapour (from 100 °C to 1200 °C) in the smelting furnace can thus be eliminated. This results in major reduction in CO2 emission and direct annual savings of several millions of dollars due to improved energy efficiency. Next step to further improve the energy efficiency, to gain substantial savings and simultaneously cut emissions is to select modern technology for the drying process. Consequently, all CO2 emission will be completely eliminated (from 40,000 tpy down to 0 tpy), NOx emission will be negligible, and the SO2 emission will be reduced by over 99 %. Switching of conventional direct heated drying technology to modern indirect steam drying brings, in addition to dramatic emission reduction, additional savings due to further improved energy efficiency. Direct energy savings count for 900 – 1300 MJ/t H2O, which depending on the concentrate feed rate and its moisture load can be worth several millions of dollars every year. Additional savings in operational expenses related to drying and gas cleaning may be worth a few million dollars more. Sustainability is a key issue today, and major savings together with significant emission reduction are readily available by proper technology selection for concentrate drying. INTRODUCTIONSustainability is a decisive principle in any process industry accompanied with emissions and high amount of energy. This is of significant importance in metal processing, including concentrate drying, where minimum impact on the environment, people and community are targeted, and all this with minimum cost, effort and resources. Therefore, special attention is paid to high energy efficiency, low energy consumption with preferable utilization of waste energy, safety issues, availability, level of maintenance, cost of maintenance, and emissions among other things.Non-ferrous metal concentrates can be dried using various techniques. Conventional drying based on direct heating, and use of fossil fuels for drying energy has almost entirely been replaced by steam drying. It is based on indirect heating and it has become the most dominant drying technology for copper concentrates during the last decade with over 90% of the market share of all new dryer installations. Among the steam dryers the Kumera Steam Dryer is the most pre-dominant technology with some 70% of all new dryer installations world-wide."

Jan 1, 2012

By J. P. Sims

Abstract - Ultramafic to mafic igneous intrusions of the Las Aguilas district form part of a belt of generally mafic plutonic bodies within medium- and high-grade early Paleozoic metamorphic rocks in the southern Sierras Pampeanas region, Province of San Luis. The intrusions host the largest known nickel sulfide resource in Argentina and contain significant Cu, Co and PGE mineralization (2.2 Mt at 0.5% Ni, 0.5% Cu, 0.035% Co). Sulfides at Las Aguilas Este, one of two principal mineralized zones, are hosted by a body comprising subvertically dipping units of predominantly orthopyroxenite and melanorite cumulate, with lesser dunite, harzburgite, norite, leuconorite, and amphibolite. The units are zoned horizontally from ultramafic to mafic compositions, representing primary magmatic zonation away from an original base or side of the intrusion. Intercumulus nettextured and disseminated aggregates of pyrrhotite-chalcopyrite-pentlandite are concentrated in the peridotitic zones and extend into melanorite. Whole rock major and trace element compositions, and olivine chemistry, indicate that the parent magma was gabbroic/basaltic with 100 (Mg/Mg+Fe) near 59, and resembles tholeiitic magmas generated in subduction-related arc, or back-arc settings. Unusually aluminous Cr-bearing spinel is compositionally similar to those in some synorogenic mafic/ultramafic plutons in magmatic arc settings. Relatively Ni-depleted olivines and low Cu/Pd ratios are indicative of magmatic sulfide segregation early in the crystallization of the magma. Early orthopyroxene saturation and virtual lack of clinopyroxene, in conjunction with sulfur isotope values up to +6.6 ‰, spinel compositions, and presence of graphite, phlogopite and magmatic hornblende, all attest to probable crustal contamination of the parent magma. Assimilation of crustal sulfur may have been crucial in the early attainment of sulfide saturation and resultant formation of magmatic Ni-Cu sulfide mineralization. Fabrics, textures and mineralogy of the intrusions and country rocks and U-Pb zircon dating indicate syntectonic-synmetamorphic emplacement at 478±6 Ma during the Famatinian (Ordovician) orogeny. Minor to locally significant recrystallization and deformation of mafic-ultramafic rocks and redistribution of sulfides and PGE occurred during and following the Famatinian orogeny. The Las Aguilas intrusion is one of several tholeiitic mafic-ultramafic intrusive complexes within an Ordovician arc - back-arc system in the Sierras Pampeanas. Aeromagnetic datasets and regional mapping suggest there is further potential for intrusion-hosted Ni-Cu mineralization along this eroded magmatic arc.

Jan 1, 1999

By Witold J. S. Ostrowski

The shaft structure being part of an underground mine, depends on programned functional duties, and on geological and hydrological conditions. The majority of Canadian metal mine shafts are in hard competent igneous rocks, which are in an elastic state of equilibrium around the excavation. Others penetrate soft sedimentary or very weak water-bearing rock formations in which the equilibrium varies from plastic to hydrostatic. Knowledge of how to interpret the underground conditions, determine acting forces and design proper structures is essential for the production and safety of the future mine.

Jan 1, 1973