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By D. J. McLaws

"Recent innovations in metal smelting technology utilize continuous oxygen-enriched smelting and converting processes which are capable of producing off-gases containing up to 60% SO2 or more. Other SO2 recovery processes, involving solvent absorption and steam or vacuum regeneration, can produce off-gases with SO2 concentrations nearing 100%.Processing of these high-concentration SO2 off-gases in conventional sulfuric acid plants can cause excessively high catalyst bed temperatures and poor SO2 conversion. In order to avoid these problems, a conventional acid plant design must dilute these high SO2 process gasses with dilution air in order to provide the required oxygen to effectively convert the SO2 and provide a heat sink (via the inert N2) such that the exothermic reaction, SO2 + ½ O2 ???SO3, does not exceed the temperature limit of the catalyst or the converter vessel.MECS, Inc. (MECS) has proven that a high SO2 feed gas design can be a viable option which can increase energy recovery, reduce energy consumption and potentially reduce capital costs."

Jan 1, 2014

Traditionally within the mining industry, single models for both grade and geology of orebodies are created upon which all mine development decisions are based. These models provide a single interpretation of the extent and continuity of the mineralization envelope based on solids and sections interpreted from relatively wide spaced drilling i.e. the models infer behaviour of grade and geology at smaller/local scales based on data available at wider scales. The variable behaviour of grade and geology cannot be derived from single kriged resource models. In recognition of this, Newmont Mining Corporation typically uses Sequential Gaussian Simulation (SGS) to quantify grade variability and to determine its effect on some of these mine development decisions. In most of these studies the mineralized envelope remains fixed and grade simulations are generated within a fixed volume. To account for uncertainty in the geology/ mineralization envelope Newmont Mining Corporation has been experimenting with Multiple Point Statistics (MPS). Multiple-Point Statistics is an emerging technique, which can be used to generate multiple, geologically realistic, realizations of data that displays complex non-linear features. MPS uses a conceptual model of the geology, called a Training Image (TI), to infer these high-order spatial relationships. The multiple realizations allow for an assessment of the geologic uncertainty, which can be further combined with grade simulations to generate a more complete picture of the true uncertainty of a mineral deposit.

Jan 1, 2011

By Ilpo O. Auranen

Background: Mines of today are moving ever increasing tonnages of rock. The new ore bodies tend be of lower grade and located deeper in the earth?s crust. The industry?s focus to overcome this ?deeper but poorer? ore problem has traditionally been to lower the costs by increasing the scale of mining. This has resulted in an ever increasing size of mining equipment like drills, loading shovels, dump trucks. The main focus has been in reducing the cost per ton of mining. This cost focus has often resulted in increased waste rock dilution and more ore losses. From costs to value: Waste rock dilution means waste rock in the concentrator feed. It?s value in open pit mining is equal to the value of ore it replaces. In underground mining, waste rock dilution?s value is equal to the value of ore it replaces added to the costs of mining it. It is commonly accepted that waste rock dilution in open pit mining ranges between 5 and 20% and in underground mining between 5 and 40 % . In a typical large open pit mine ore value is from 20 to 60 USD per ton and mining costs are 1 to 3 USD per ton. One percentage point reduction in waste rock dilution represents savings corresponding to about 20% of total mining operation costs. The difficulty of reducing waste rock dilution comes from the complicated nature of the ores. Accurate ore waste-border detection has not been possible due to excessive costs. Core drilling combined with geochemical lab analysis is the most accurate method for locating ore waste borders. However, it is also expensive and time consuming, which is why it is often combined with somewhat lower cost methods like sampling drill cuttings from blasting drill holes or from reverse circulation drills and analyzing them in a laboratory. The main drawback with these methods, in addition high costs, lies in the sampling accuracy and in the quality control of the whole process when a large number of samples have to be handled manually. In every mine it is possible to halve waste rock dilution by using new on-line analysis technology .

Oct 1, 2009

By V I. McCallum

In 1954, Falconbridge Nickel Mines Limited began the program of deepening the Falconbridge mine workings for 2,000 feet below the bottom, or 4025, level in order to provide twelve new levels for production. Involved in this program were a production-sized internal shaft, .crushing, pumping and hoisting installations, the integration of the new shaft operations with those of existing shafts, and considerations of ventilation requirements and ground support at depth. This paper describes the major items of equipment, and the depth development of No. 9 shaft as a whole, and also emphasize the planning phases of the program. The factors involved and reasons for the equipment and layouts chosen are given. Introduction and History THIS paper describes the planning and development of that portion of the Falconbridge mine between the 4025 and 6050 mining levels. This mine, the oldest of several being operated by Falcon-bridge Nickel Mines Limited in the Sudbury district, has been a continuous producer for over thirty years.

Jan 1, 1964

By Norman O. Lotter, Dominic Fragomeni, Jorge Oliveira, Dee J. Bradshaw, Rebecca Monnapula

"The role of mixed collectors in enhancing the metallurgical performance of sulphide flotation processes was reviewed in 2008, and later published as an integrated theory by Lotter and Bradshaw, 2009. The theory proposed that xanthates, dithiophosphates and dithiocarbamates could be synergistically combined in an optimal formula to deliver improved grade and recovery. The approach uses a five-step structure, viz.1. A mineralogical study of the ore to be treated, identifying and quantifying the economic minerals (with hosting and association) and gangue species present.2. Selection of candidate collectors from this mineralogical information and from the known pulp conditions of that operation (e.g. Eh, pH).3. Design and execution of a factorial experiment to estimate and test the main effects and interactions, and to model the response surface for an optimum formulation [Box et al., 1978].4. Use of a High-Confidence Flotation Test platform in the factorial to reduce overall errors and allow for clearer observations [Lotter, 1995; Lotter and Fragomeni, 2010].5. Statistical design of a plant scale trial to measure and validate the gains [Napier-Munn, 1995; Lotter et al., 2009]. Eland Platinum, which was commissioned in November 2007, appointed a team to apply this theory to formulate an optimized mixed collector suite for use in the operation. The West Pit ore (UG2 - Normal ore) was sampled at site and brought to Xstrata Process Support, Sudbury, Canada, for mineralogical and metallurgical testing in 2008. Microprobe and QEMSCAN measurement characterized the type, grain size and textural association of the discrete Platinum Group Minerals (PGM) present. From the mineralogical data, it was clear that a mixture of dithiocarbamate and two xanthates would be a likely reagent suite selection. A factorially designed set of High-Confidence Flotation Tests studying these was performed, concluding that an optimal suite using certain amounts of these collectors was a viable formulation that would advance the grade and recovery performance at Eland above the standard PIBX by approximately 2.13% 4E PGE. The plant trial, which used a form of the replicated block design after Napier-Munn, 1995, and Lotter et al., 2009, exceeded this estimate with an overall PGE recovery gain of 2.48% (absolute basis) and a concentrate grade gain of 26.4 g/t PGE (absolute basis), as well as reducing chrome in concentrate from 2.04 to 1.62% (absolute basis). These gains proved to be statistically significant using the analysis of variance method, and have validated the theory."

Jan 1, 2011

By S. J. Haynes

"This paper documents the characteristics of the different quartz veins, and their relation to gold, in the turbiditic Meguma domain of eastern Nova Scotia. Eleven different types have been distinguished in the greenschist facies on the basis of form, internal structure, mineralogy, wallrock alteration and crosscutting relationships to each other and to regional structures. Gold is present as rare visible disseminations in host rock slates and in ore-grade, early-formed veins, that pre-date the formation of upright Acadian folds and intrusions of Devonian granitoids. Four vein types pre-date Acadian folding. Five gold-deficient vein types are associated with Acadian folding (syndeformation); whereas two gold-deficient vein types clearly post-date this deformational event: Previously unreported, wall rock alteration is associated with early crosscutting and semiconcordant auriferous veins. In contrast, early stratiform veins are devoid of wallrock alteration. It is suggested that the auriferous vein arrays formed as submarine exhalitive systems over synsedimentary tensional faults and that the Meguma domain may represent the opening of a basin similar to the modernGuaymas rift .IntroductionThe term ""turbidite-hosted gold deposits"" is introduced to distinguish gold deposits contained within a turbiditic sequence of wackes and shales (or their metamorphosed equivalents) from gold deposits in other types of sediments. Usage and justification for the term is similar to ""carbonate-hosted lead-zinc deposits"" or ""volcanogenic massive sulphides"". A range of different characteristics can be present in individual deposits, some of which may be indicative of specific deposit types in the same manner that volcanogenic massive sulphides can be subdivided into ""Cyprus type"", ""Kuroko type"", ""Besshi type"", etc. Historically, gold deposits hosted by turbiditic flysch were an important class of quartz-vein gold mines in the 19th century. They included the goldfields of Victoria, Australia, Otago, New Zealand and Nova Scotia, Canada. Production from most of these fields had ceased by World War II and interest in this type of deposit waned. However, the recent exploration interest in gold has resulted in both re-assessment of the classical mining camps and the discovery that ""turbidite-hosted"" gold deposits are present in many parts of the world.Mapping of the regional geology and gold deposits of the Megumadomain of Nova Scotia was carried out by E.R. Faribault of the Geological Survey of Canada between 1886 and 1939. Faribault produced a comprehensive series of maps and reports for each gold district, a compendium of which was published by Malcolm (1929)."

Jan 1, 1987

By A. S. Bayne

THIS paper will present a review of the mining operations of one of Canada's most lately established gold mining districts (1). The history of the Little Long Lac and Sturgeon River areas is interesting in view of the fact that, although they have long been the scene of a certain amount of mining activity, they remained little more than an uninhabited wilderness until 1933, since which time ten producing gold mines and mills have been established in permanent operation, eight of these having entered production since the beginning of 1937. As complete a background as possible will be given concerning the major influences having a bearing upon living and economic conditions in the mining communities. The object, here, is to show the diversity of problems which demand the attention of the operator starting up and operating a new mine in present times, and to indicate the ways in which these problems are successfully met in this district. A description of the power facilities and plant equipment will be followed by a summary of the problems encountered and methods applied in exploration and development. This is to aid in forming a background showing the circumstances which influence the mining methods and costs of the various operations. The paper will conclude with a description of the mining methods used and the costs of the operations, including summarized analyses of the stoping methods and mining conditions. The various phases of operation will be dealt with separately, in so far as this is possible, in order to present clearly the salient features. It is necessary, however, that the reader bear completely and constantly in mind the fact that in actual operations these phases arc, to a large extent, intimately related and greatly affect each other, as well as being, in turn, affected by other circumstances beyond the control of the operator. A few of these circumstances are: capital available during the development period and early stages of productive operation; strength of rock comprising the ore and its boundary walls; grade, size, shape, and location of ore-bodies; and many other natural items which must be carefully weighed in relation to the details of operation.

Jan 1, 1940

By Eric Low

Raising capital by issuing debt or equity is necessary in almost every corporation. In the field of corporate finance, the raising of capital is a heavily-studied topic. However, some of what is studied on this topic in corporate finance is not applicable in the mining industry. There are also many financing options that were created for the mining industry such as flow-through shares, prepaid forwards, and royalty sales. The cyclical nature of the industry makes the risk-return profile of financings more difficult to estimate than in other industries. Additionally, the methods used to assess firm value are different than other industries, as the values of orebodies are not included on balance sheets. For precious metals companies, which are a hedge against most other securities, there are additional complications with determining investor expectations and cost of equity. This thesis puts forth a decision-making framework to explain mine financing choices from the perspective of mining companies. The approach is threefold. First, all of the major equity and debt financing instruments available to mining companies are presented and analyzed. Each financing method is assessed on a wide range of criteria. Next, these concepts are applied in case studies of four companies: BHP Billiton, Barrick Gold, Teck Resources, and Noront Resources. For each company, the overall choice of financing methods is shown and analyzed. The effect of financing choices on the weighted average cost of capital (WACC) is calculated. The final section deals with case studies of individual mine finance decisions during the past two years.

May 1, 2011

By J. D. Nye, I. A. Farr, W. J. D. Stone

"A unique deposit of barite exists near Brookfield, Nova Scotia. The crystals are extremely fine and the whole deposit virtually free of heavy metals. The deposit size was not large enough for conventional uses, such as the production of barium carbonate and drilling mud. In an effort to obtain maximum utilization, a program was begun to determine if U.S.P.-grade pharmaceutical barium sulphate for X-ray diagnosis could be produced. Early work was sufficiently encouraging to institute a development program under the federal Program for Advancement of Industrial Technology. This has been very successfully completed. Canadian and U.S. process patents have been issued, clinical trials have been successful, a production plant has been designed and the plant’s production sold. The processing plant will include magnetic separation for the removal of iron minerals, fine grinding by paddle milling to minus one micron and acid leaching. The process is unique in that at no time is the barium taken into solution.Information is given on the deposit, process, markets, use, plant capital and operating costs, and projected profits. The initial production plant will have an annual capacity of 2,000 tons per year of end product. Capital cost is $850,000 and annual turnover more than $1.5 million. As this capacity only represents approximately 15% of the North American market, rapid plant expansion is foreseen."

Jan 1, 1980

By C. Pelley, A. Piche

"The Canadian mining industry faces the prospects of a severe shortage of graduate mining engineers over the next decade. This arises from three factors: first, a growth in industrial activity; second, the average age of company engineering and management staff; and third, the reduced number of students in engineering faculties around the world. This paper aims to identify the critical factors underlying the trend of inadequate recruitment into higher education for mining and to examine means of alleviating the problem.This paper is based upon surveys of potential and current students and graduate mining engineers from four mining schools. An attempt is made to understand institutional and industrial images, career prospects and what is required to attract enough high-calibre young people into mining education over the next decade.IntroductionThe mining industry has started to experience a severe shortage of graduate mining engineers which is likely to persist and even worsen in the short- to medium-term.This arise s from three principal factors:1. a recent and strong growth in mining activity, which surpasses that experienced through the 70s, before the recent international industrial recession; .2. an increasingly older average age of mine engineering employees, at least in the industry's larger companies; and3. problems associated with maintaining adequate mining undergraduate recruitment levels ."

Jan 1, 1989

By A. M. Glendinning

"IntroductionLocationTHE PROPERTY of Aunor Gold Mines, Limited is in Deloro township, Ontario, about three miles southeast of the town of Timmins. It consists of a group of eleven claims located between those of Buffalo-Ankerite Gold Mines, Limited, and Delnite Gold Mines, Limited.GeologyThe ore zone at the Aunor mine consists of a narrow band of fine grained pillowed andesite, irregular bands of 'brown to green carbonated andesite, and lenticular bodies of quartz feldspar porphyry. The zone strikes N.80°E., dips 60 North, and has been traced for 5,000 feet across the property. It varies in width from 0 to 250 feet and is bounded on the north and south by masses of dark bluish-grey tale chlorite schist. These schist bands have widths up to 500 feet.The ore occurs in a series of parallel and branching veins confined to the limits of the zone. These veins tend to terminate and die out on the footwall schist contact, striking generally parallel with the ore zone. In wide sections of the zone, 150 to 250 feet, the veins range in width up •to 3.5 feet and may occur in two or three horizons across the width of the zone, each mineable independent of the other. They tend to dip a little flatter than the general dip of the zone. Where the zone is narrow, the veins are so closely spaced and numerous they can be mined together and in some places the complete zone has been mined from schist to schist."

Jan 1, 1953

By Karl J. C. Harries

"2.1. INTRODUCTIONNo agreement can be perfect in the sense that it contemplates and provides for all eventualities. Mineral acquisition agreements are usually negotiated and drafted at a time when an orebody is no more than a gleam in a geologist’s eye, so it is hardly possible to provide for development and operation in other than the most general terms. However, an agreement that stops short of contemplating the possibility of an orebody and production is ill-advised. Accordingly, it is important to provide procedures to make decisions that will let the project proceed, even in the face of a fallingout between parties. Whether the parties are shareholders in a corporation or venturers in a contractual common undertaking like a joint venture, differences of opinion and disputes will occur. Unfortunately, more and more are ending up before the courts. Besides greed and the growing tendency in society to fight rather than talk, there are other factors that contribute to the increase of litigation. In some jurisdictions, agreements have tended to become complicated, often defying interpretation, even by a lawyer, and explorationists want their budgets to go into the ground as constructive work rather than into a lawyer’s pocket. All this has led to a growing tendency for corporations to take the attitude that the chances of finding a mine are, at best, marginal and there are lots of earlier agreements in the files to draw from, so why not prepare their own agreements? As discussed in the preceding chapter, this can be folly. All these factors can quickly have parties facing each other in court while a project sits idle. Added to this is the problem that, in some jurisdictions, lawyers may take cases on a contingency-fee basis, sometimes promoting the pursuit of a nebulous claim.When an orebody is discovered, someone will always want some, or more, for himself. There is a breed of “prospectors” who prospect for legal actions, on the somewhat sound grounds that a major corporation will buy off nuisance litigation, rather than incurring the cost and effort of attacking even a poorly founded claim in the courts. They may even find a winner. Besides, it is far more comfortable and relaxing to prospect for problems and legal niceties than to prospect for an orebody.1 In short, it is appropriate to consider briefly some of the factors relating to lawsuits and judgments. Although many of the comments are made in the context of the common law and the Canadian legal system, most of the concepts and suggestions are applicable to any legal system."

Jan 1, 2003

By S. K. Mitterecker, T. Hofbauer, F. Baerhold

"Acid regeneration is a very important process step in each acid leach circuit. It is required to recover dissolved metals and HCl from spent leaching acid. Andritz Metals presents its recently commissioned spray roast pilot plant. The facility is now available for testing and demonstrating acid recovery or metal oxide production which is a requirement in several flow sheets under development for the mining and specialized oxides industries. Results from pilot test campaigns are reported here. We are currently focusing on a nickel ore leaching process, which requires both a feasible iron control and acid regeneration step. In addition, we disclose the results of a magnesium ore and aluminium recycling test campaign conducted in our pilot plant facility.INTRODUCTION Hydrochloric acid regeneration is widely used in the steel industry to regenerate spent pickle liquors into hydrochloric acid at a typical concentration of 18 wt.%. Andritz Metals (formerly known as Ruthner) has built more than 200 acid regeneration plants worldwide (Andritz Metals brochure). As technology leaders Andritz also has vast experience with specialty metal oxide plants, producing metal oxides such as aluminium oxide (Al2O3), magnesium oxide (MgO), nickel oxide (NiO), cobalt oxide (Co3O4) and mixed oxides from metal chloride solutions (Baerhold F., Lebl A., Starcevic J., 2006), (Jedlicka, H., n.d.), (Ruthner M.J., Krischner H., 1973), (Ruthner Ind. Planungs AG, 1967). Hydrochloric acid leach circuits have been developed and proven in the industry for many years. Examples of industrial applications are: synthetic rutile production (TiO2) (Walpole E.A., Winter J.D., 2002), Quebec Iron and Titanium’s UGS process (Patoine M.-C., De Mori A., Borowiec K., Coscia C., 2002), magnesium and potassium production (Priemer H., 1973) and Goro Nickel (Vahed A., Colton D.F., Duterque J.P., Karner W., Baerhold F., 2004), (Taylor A., 2013). One of the critical process steps in developing a hydrometallurgical process is acid regeneration, as it is an economic requirement to recover both the dissolved metals and acid (commonly HCl) from the spent leaching solution."

Jan 1, 2016

By W. A. Gow, H. H. McGreedy

It is believed that many of the problems encountered in the operation of gold cyanidation plants are difficult to resolve due to the lack of sufficient and reliable in-formation regarding the variations and actual values of operating variables at any given time. The application of instruments to monitor the more important variables in the cyanidation process should result in more efficient plant operation and a better understanding of the process. The use of pH and conductivity sensing devices for alkalinity measurements, a monitor to determine the dissolved oxygen content of plant solutions, a continuous cyanide titrator and sonic control of grinding circuits are discussed. Although the discussion is oriented toward the cyanide process, much of the paper is applicable to other ore treatment operations.

Jan 1, 1966

By Hugo Julien

According to OSHA 29 CFR Part 1910.119 (Process safety management of highly hazardous chemicals), Canadian Provincial Safety Standard Acts or Federal laws, the owner of stationary equipment (Boilers, stacks, piping, pressure vessel, etc.) should follow a complete inspection plan and follow an Integrity Operating Windows (IOW’s) adapted for each of them. Some important variables shall be included in the inspection plan such as specific damage mechanisms versus alloy used in the original design, process conditions, etc. Some North American’s standards exist, like the one listed in ASME PTB-2-2009, to help owner to create such inspection program. The new API RP 584, Integrity Operating Windows (IOW’s) can guide Mining & Metals owners to find out their specific IOW’s. Inspection frequencies are often described in the Jurisdiction Safety Acts such as the British Columbia B.C. Reg. 104/2004, etc. but often left in the owner representative responsibility (Bill C-21, federal Act to amend the Canadian Human Rights Act). Every deficiency should be repaired according to recognized Codes such as ASME PCC-2, etc.. If flaws not conforming to the original Code of construction are found, this article will introduce the Fitness-For- Service assessment principles to be able to accept it without any repairs.

Jan 1, 2014

By G. Merle, David L. McKay, Elmar Randveer

"THE ENGINEERING AND TECHNICAL SERVICES department is responsible for supplying the following services:1. Administration and co-ordination of the work required for capital projects.2. Engineering, design and drafting services for inplant changes or improvements as requested by the operating• and maintenance departments.3. Rock mechanics.4. Preparation of plans and layouts required for efficient extraction of the ore as mutually agreed with the mine operating departments.5. Mine planning and long-term schedules in co-operation with the mine operating departments.6. Grade control (long term and short term) and the preparation of ore and waste removal schedules to maintain a uniform grade of mill feed. This also includes the calculation of metal reserves and metal production forecasts.7. Surveying, underground and surface.8. Operations research at the mine site.9. Industrial engineering.10. Chemical analyses and assays.11. Instrumentation.12. Environmental control.A staff of approximately 35 supervisors, engineers and scientists, and 80 technicians, supply the foregoing services. Consulting engineering and drafting firms are used to supply specialized services and technical personnel in-house at Timmins to handle overloads on capital projects under the direction of Ecstall engineers.The operating and maintenance departments depend on the engineering department to supply engineering, design and drafting services for any new facilities or for any planned alteration to existing facilities. To do this efficiently requires a high level of communication and co-operation with these departments. This has been a major factor in developing the present organization of the department shown in Figure 63.The organization is predicated on a strong central technical and engineering resource from which personnel can be assigned responsibilities for different projects, and in different areas, as the work load demands. Job satisfaction is very high because of the variety and challenge in the tasks. Additionally, participation in projects with production and maintenance personnel broadens each technical employee's knowledge of operating and maintenance problems."

Jan 1, 1974

By James W. Cassie

The Snap Lake Diamond Project is located approximately 220 km northeast of Yellowknife, NT, Canada at an approximate latitude of 63?35?. The project location is within the zone of continuous permafrost; measured ground temperatures are about ?2?C at 10 to 20 m depth below surface. The site is located on a peninsula jutting into Snap Lake. The site is generally barren of vegetation, except for some isolated areas with low trees located in topographic lows and near the shoreline of Snap Lake. As part of phased evaluation process with regards to the mining project, an Advanced Exploration Program was undertaken in 2000 and 2001. This program included the underground extraction of a bulk sample of kimberlite, which was processed on site. A Processed Kimberlite Containment (PKC) area was required as part of this program. The area chosen as the PKC facility was a small inland lake, called Inland Lake #1, on the peninsula. Construction of the PKC area required the construction of two dams, one on either end of the lake. At the south end of the lake, Dam 1 was constructed partially on a talik and partially on continuous permafrost. Dam 2 was constructed entirely on permafrost. The effects of the remote location, selection of suitable construction materials and permafrost conditions on the designs of the dams are discussed. A description of the design elements and construction schedule are provided. A review of the performance of these two dams, in terms of settlement, deformations, pore pressures and thermal regime, over the last several years is provided.

May 1, 2003

The common theme of these four objectives is declaration. Declaration tells the compiler that an entity exists and also provides the name and nature of the entity. Since everything you create has to be declared, you must know how to declare correctly and be able to make appropriate use of all the declaration tools available to you. This objective recognizes the importance of declaration by requiring you to know everything about Java declarations Write code that declares, constructs, and initializes arrays of any base type using any of the permitted forms both for declaration and for initialization. This objective addresses your understanding of all aspects of arrays. Arrays are the simplest possible data collection and are supported by all modern programming languages. However, Java?s arrays are different from those in other languages, especially C and C++, because they are actually exotic objects. This objective recognizes the importance of being able to make use of all the functionality of arrays. You will be expected to know how to declare, construct, and initialize arrays.

May 1, 2011

By G. A. Vissac

In this paper we intend to deal particularly with the economic side of coal washing as it applies to our mines. We will then discuss why the dry-cleaning process has been selected, and give a brief description of our plant, dwelling only on its specific features and referring the reader to the numerous papers published on the subject for any details on the principles and machinery used in dry cleaning. ECONOMIC DISCUSSION The washery introduces an extra cost for depreciation, operation, and loss in treatment. A certain proportion of the coal, now being sold, and which the miners have been paid for. will have to be wasted. As a whole, the total increase in cost would be approximately 60 cents per ton. On the possibility of recovering this amount depends the success of the washery. There are two advantages to be expected from the washery, the first, which occurs at the mine and which will be certain; the second, more difficult to estimate, because it depends upon convincing our customers that they should pay more for a better product.

Jan 1, 1924

By Michael Young, Josh Rubenstein, Michael Cooper, Tom Shouldice, Dan Curry

"Xstrata Nickel Australasia’s Cosmos plant in Western Australia is currently implementing a debottlenecking project to increase nickel output while maintaining metallurgical performance and a low unit cost for production. Mineralogical analyses indicated that the processing bottlenecks could be removed by simply reconfiguring portions of the circuit as well as adding capacity with technical advancements – notably an IsaMill™, Jameson Cell, Wemco® SmartCell™ and Larox Filter.The Wemco® SmartCell™, which is particularly suited for coarse mineral flotation, and Jameson Cell, which is particularly well suited for fast floating and fine minerals, combine as rougher scalpers to complete the main stream portion of the flotation circuit. Addition of the two new cells meet the required flotation capacity to handle the forecast increase in nickel feed grade and tonnage.The addition of an IsaMill™ for regrinding allows the SAG mill to produce a coarser primary product, thus enabling increased throughput. The advantages offered by the IsaMill™ include operation in open circuit (internal classification), an inert grinding environment (ceramic media) for better downstream flotation (“clean” new surfaces), compact footprint (easy to retrofit into existing plant) and energy efficiency. With the new rougher capacity addition, the remaining original plant cells were reconfigured to suit the new regrind mill and cleaning requirements. The existing 24 m2 Larox pressure filter was replaced with a larger 32 m2 unit to dewater the increased concentrate output.The paper describes the upgrade at the Cosmos concentrator with particular emphasis on the mineralogical data and metallurgical benefits associated with the changes.INTRODUCTIONThe Cosmos concentrator is located 680 km northeast of Perth in Western Australia. The deposit’s development and operations were started in 1999 by Jubilee Mines NL, Cosmos’ previous owner, with the first production of nickel concentrate in April 2000. The Cosmos concentrator treats a komatiite hosted high grade nickel sulphide ore, with sulphides being predominantly pentlandite and pyrrhotite with lesser amounts of pyrite and chalcopyrite."

Jan 1, 2010