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By D. Hatfield

"Flotation plants typically aim to maximise recovery at or above a target grade. As the ore from the mine varies, operators increase or decrease the mass pull in different flotation banks by adjusting air and level set points in order to achieve target concentrate grade. A methodology has been developed to maximise overall recovery at target grade by determining the optimal mass pull for each bank. However, the approach of targeting equal grade for each ore type in the deposit leads to sub-optimal overall recovery. This is because some ore types sacrifice a large amount of recovery to reach target grade while others easily achieve target grade and can be processed at higher than target grade for little or no loss in recovery. Processing different ore types at different grades and blending the concentrates therefore gives a higher overall recovery.This paper presents a case study where an 80 year production forecast was made for a large Chilean copper concentrator in feasibility stage. A circuit model was created using SGS’s Integrated Geometallurgical Simulator (IGS) for the different ore types to be processed. The model was calibrated from standard rougher flotation tests (MFT), cleaner tests and from the results of plant surveys of similar operations. The pull rates for each bank in the circuit were determined to achieve an optimal graderecovery curve for each ore type. These curves were combined at different concentrate grades for each ore type to obtain the mathematically optimal overall recovery at target grade. The paper shows a methodology for obtaining an optimal combination of operating conditions for each ore type to maximise overall recovery at a set combined concentrate grade."

Jan 1, 2013

By E. Fried

Cemented paste backfill (CPB) is an innovative tailings management method that consists in returning considerable amounts of mine tailings into the underground mine openings. The filled stopes thus participate to the ground support that allows maximizing orebody extraction and a safer environment for the mine workers. There are also significant environmental advantages of using CPB. Indeed, up to 50% of the concentrator tailings can be backfilled, leading to a smaller volume of problematic waste materials to be managed at the surface. Once the CPB is placed, or when the mine is flooded at its end-life, the backfill is subjected to underground water flows that may leach and spread the pollutants (mainly metals, sulphates, and acidity) which can contaminate the underground waters. The aim of this study is to characterize the leaching properties of CPB material and to identify the cement phases that ensure the metal fixation. A laboratory procedure was implemented consisting in the preparation of various paste backfill mixtures using sulphide-rich and sulphide-free materials, different types of binder, and mixing waters having various sulphates, copper and zinc concentrations. After 90-days curing time, the samples were submitted to column leaching tests. The CPB materials were flushed each day with 100 ml of deionised water during 100 days. The collected leachates were then analyzed for pH, Eh, electric conductivity and chemical composition. For some samples, a differential acid neutralisation test was carried out. The objective of this experiment is to dissolve selectively the hydrated phases by adding incremental acid concentrations. By analyzing punctually the equilibrated solutions, the composition of the dissolved phases and their metal content can be estimated. The leaching test results showed that the pH of the leachates remains alkaline during the test period. When the pH decreases under 10 (after 30 days), different behaviours in terms of chemical element release (especially for zinc) were observed. During the test, the oxidation of pyrite seems to slow down, probably due to passivating phenomena. Moreover, the differential acid neutralisation test results allowed a better understanding of the CPB mineralogy and the Zn-bearing cement phases. Zinc and the other metals seem to be fixed within a calcium-magnesium silicate.

May 1, 2007

By W. R. Green, B. W. Barde

"Geological exploration involves the collection and analysis of a wide variety of information. A basic problem in interpretation is to determine the interrelationship s of the different data. A number of statistical methods can be applied to this problem, provided that subsets of data can be selected.We have recently developed a set of interactive computer programs which provide the cap ability to quickly examine a large set of data, and may be used by people with little previous computer experience. There are two main stages in using this system. First is selection of subsets of data , by applying various tests on the values of given items. This includes matching specific entries in descriptive fields, and minimum - maximum tests on numeric fields. The second stage is basic statistical analysis and data display , including histograms, 2-D scalier plots, probability (cumulative frequency) plots, and correlation matrices. All output can be viewed on a computer terminal, and important parameters changed to produce the most effective display for use in interpretation.This system has been applied to a number of different exploration problems. An example was the determination of the nature and extent of mineralization of a gold prospect in the Queen Charlotte Islands, from drill-hole data. With the aid of the computer programs , a mineralized zone was defined, and locations for further exploration identified."

Jan 1, 1984

By R. E. Michelutti

"The Sudbury area environment became drastically altered commencing in 1871 with lumbering, repeated fires and early open roasting operations from 1887 to 1929. These combined factors had such a pronounced effect that approximately 24 square miles were totally denuded of any vegetation and 87 square miles were semi-barren to somewhat stressed.The two nickel producing companies in the area have reduced the sulphur dioxide emissions considerably over the years. Falconbridge Limited, alone, reduced sulphur dioxide emissions by 77% from 1971 to 1984.These reductions have resulted in improvements to the air, soil, lake and vegetation quality in the Sudbury area.INTRODUCTIONThe Sudbury area environment became drastically altered commencing in the 1870's with lumbering, repeated fires and early open roasting operations from 1888 to 1929. These combined factors had such a pronounced effect on the Sudbury environment that approximately 24 square miles (64 sq. km.) were totally denuded of any vegetation and 87 square miles (225 sq. km.) were semi-barren.Over the years, the Sudbury area environment has improved considerably. This has been due to emission cutbacks by both Inco Metals and Falconbridge Limited, coupled with industry, government and community reclamation programs. Before the improvements are discussed, a better understanding of the historical degradation is required."

Jan 1, 1986

By C. J. Brown

Controlling the level of impurities in copper refinery electrolytes is essential to achieving acceptable cathode purity. Purge of electrolyte is not an entirely satisfactory solution since the cost of neutralization, waste disposal, and replacement acid can be appreciable. The APU® process utilizes ion exchange resin to sorb sulphuric acid while rejecting metal salt impurities. Extensively employed for recovery of waste pickling and anodizing acids since 1977, the system is now being used at several refineries for removal of contaminants such as antimony, bismuth, iron, and nickel. The purified acid, which is recovered from the resin by water elution, is recycled back to the refinery tank-house, while the metals are typically recovered from the de-acidified by-product solution by precipitation.

Jan 1, 2005

By Michael Cooper, Eric Konigsmann, A. Moerman

"A paste backfill plant and underground piping distribution system was commissioned at the Brunswick Mine in June, 1998. Concentrator tailings, composed mainly of pyrite and lesser amounts of silicate minerals with a P80 of 37um (45 YO-20 pm), are pumped to the backfill plant. The backfill plant uses conventional thickening and disc filtering to dewater the solids, which are then mixed with binder in twin screw mixers. The paste is discharged through a gob hopper and one of three boreholes by gravity. Approximately 65% of the concentrator tailings will be placed underground at full production. The remaining thickened tailings will be pumped to an existing impoundment area. Application of paste technology will completely replace the use of cemented rock fill in the mine by the end of 1998.The design capacity of the paste backfill plant is a total of 360 dmtph of cemented paste through two parallel production lines. The plant is highly instrumented and controlled via a hybrid Programmable Logic Controller (PLC-5) and Fisher ProVox Distributed Control System that is in communication with the property information highway. Video and audio signals from the underground system are carried to the surface plant via a leaky feeder communications/fiber optic system.The underground distribution system consists of a network of 200mm diameter boreholes and piping. There are approximately 3.5km of boreholes and 5.5km of piping in the system. To minimize pressures, the greatest piping length from any borehole is approximately 400m with all piping being open-ended. There are no valves in the entire paste distribution system.Construction of the plant, including installation of piping to and from the plant and preparation of the underground distribution system, was completed in less than one year from the time of management approval for the $M 22.3 project."

Jan 1, 1999

By E. Henry, C. Mayer, H. Rott

Hangingwall deformation monitoring at Kiruna mine is a major concern for Luossavaara- Kiirunavaara AB (LKAB) since underground production is deepening toward the town of Kiruna. In the quest for more effective monitoring techniques, LKAB decided to evaluate the ability of satellite-borne synthetic aperture radar (SAR) interferometry to monitor ground subsidence by generating continuous deformation maps from satellite radar images. While adopted by other geoscience-related industries, SAR interferometry is still relatively untested in the mining industry. This paper describes the basic principles of SAR interferometry and describes how subsidence is monitored at Kiruna mine. The encouraging results are discussed as well as the benefits (continuous deformation mapping, low cost, fast, etc.) and limitations (sensitivity to snow and vegetation cover) of the technique.

Jan 1, 2004

By K. G. Stowe

"1. Introduction Mattagami Lake Mines and Orchan Mines operate zinc copper mines adjacent to one another near Matagami, Quebec, situated approximately 300 kilometres north-east of Rouyn-Noranda. (Note: Mattagami Lake and Orchan are in the process of being absorbed by Noranda Mines and will become Noranda Mines-Matagami Division). Both concentrators began operations in late 1963.The Mattagami Lake concentrator is capable of treating up to 3,500 metric tons per day of massive sulphide ore with a mineral composition shown in TABLE 1. The Orchan concentrator consists of two separate circuits - the Orchan circuit with a capacity of 1,050 metric tons per day and a custom circuit with a capacity of 825 metric tons per day. Throughout its operation, Orchan has custom milled ore from several smaller deposits in the Matagami district."

Jan 1, 1979

By Tom Cooney

A small number of mining contractors worldwide have evolved their businesses to be able to provide a ?total service solution? to their clients. Thiess, an Australian-based international mining service provider, works with numerous clients to tailor delivery methods and commercial arrangements to suit individual projects. The benefits of Thiess? extensive experience is brought to each client and project, whilst business improvement within projects, to the mutual benefit of both the client and Thiess, is a key part of all long term contract relationships. Historically, optimal business outcomes were closely related to the achievement of production and cost performance measures. Whilst these remain fundamental to successful mining businesses, other elements of sustainability are assuming increasing importance. As a large energy user, greenhouse and energy management is becoming an important part of Thiess? business. Thiess is a signatory to Australian government initiatives such as Greenhouse Challenge Plus, and is integrating energy management into its operations and business improvement programs, in many cases to the benefit also of the client. This paper will highlight the benefits that an organisation such as Thiess can bring to a mine owner. Thiess? approach to business improvement and cost reduction, sustainability and energy management, as well as the relationship between these will also be considered. Increasingly, overall mining performance is dependent on the alignment of formally disparate elements.

May 1, 2007

By M. Veiga, L. Lavkulich, R. Pakalnis, M. Ghomshei, S. Baldwin, J. A. Meech

"On July 26, 2000, the Canada Foundation for Innovation announced an award of $1.3 M dollars for The Centre for Environmental Research in Minerals, Metals and Materials, CERM3, at The University of British Columbia. Additional funding was also provided by the British Columbia Knowledge Development Fund ($1.3 M) and the UBC Stewart Blusson Fund ($0.7 M). Annual industrial grants and contracts are providing support funding for the on-going research projects. Corporate membership in CERM3 entitles each participant to a seat on the technical advisory committee (TAC) as well as access to the five laboratory facilities currently under construction. Both the federal and provincial governments will also participate in the TAC through NRCan-CANMET and the BC Ministry of Energy and Mines, respectively. CERM3’s mission is:• to develop innovative methods to deal with environmental problems created by mining activity;• to promote sustainable development as a hallmark of management decision-making; • to produce mining and processing engineers with the required environmental skills; and• to enhance the image of mining in society as a vibrant and necessary component of a modern economy and society which disturbs the environment for the benefit of mankind.CERM3 brings together a multi-disciplinary team of researchers from over 12 departments at The University of British Columbia (UBC) to work on mining-related environmental problems. These include: chemistry; soil sciences; chemical and biological engineering; earth and ocean sciences; microbiology; civil engineering; electrical engineering; metals and materials engineering; mechanical engineering; mining and mineral processing, the Westwater Research Centre; the Institute for Resources and the Environment; and the School of Occupational and Environmental Hygiene. The centre intends to interact with scientists from industry, governments and other universities across Canada and around the world. CERM3 aims to become Canada’s leading environmental research facility for the mining industry. This paper describes the evolution of CERM3 and its coordinated multi-disciplinary approach to mining and the environment. Some of CERM3’s research projects include:• developing new protocols for environmental analyses to provide consistent and reliable assays;• isolating a natural virus for Thiobacillus ferrooxidans and other bacteria responsible for acid rock drainage (ARD);• designing bio-remediation and adsorption techniques for mine effluents;• promoting and enhancing the use of hydrometallurgy to reduce environmental pollution;• examining new approaches to comminution to decrease energy consumption;• developing a magnetically levitated hoisting system to reduce the footprint of a mine operation;• building a state-of-the-art supercomputer network laboratory for mine/mill simulations; and• designing intelligent bulkheads to seal tunnels following mine closure to survive for 1000 years.This latter project involves the establishment of a research station at the Britannia mine site, 45 km north of Vancouver, which will provide a full-scale facility to design the “Millennium Plug” and contribute directly to the solution to one of North America’s worst ARD-contaminated sites."

Jan 1, 2003

By F. Charette

The paper reviews recent investigations of the impact of corrosion on the performance of both plain and coated Swellex rock bolts. It addresses the problems associated with estimating and predicting corrosion rates of friction bolts, and based on field data it suggests an empirical relationship to predict corrosion rates. A review of the necessary qualities for a protective coating leads to recent experience with coated Swellex bolts that suggest that they can contribute to extending the useful life of Swellex bolts in potentially corrosive environments.

May 1, 2004

By T. P. R. de Jong, H. Harbeck

"This contribution reports recent mineral sorting experience and lists the opportunities of the newest generation of automatic sorters with a special focus on electromagnetic detection and Xray transmission. With the available sensor resolutions and actuator systems that are available today sorting of minerals down to 2 mm size and up to 250 mm lump size is technically feasible. In industry, ore as well as coal is still hand-picked and current automation potential only utilised in a handful of specific applications. Recently a number of technological developments took place that may increase sorting potential, save mill costs and lead to lower overall tonnage costs.They are:??High speed and high resolution sorting systems based on X-ray transmission imaging??High speed on-line image processing and further development of advanced data processing??Modular multi-sensor automatic sorting units (using one or more sensors such as colour, electromagnetic and X-ray in a single device)??Sensitive electromagnetic sensors for sorting based on differences in magnetic susceptibility and electric conductivityThe above enables compact dry separation, insensitive for moisture fluctuations and at high separation sharpness, as well as “electronic” high gradient magnetic separation for larger particles. Besides conventional X-ray transmission (XRT), dual-energy XRT (DE-XRT) is now being redesigned to meet the requirements of the mining industry. The mentioned technologies provide automatic dry separation of minerals and rock as alternative for conventional processing."

Jan 1, 2005

By A. K. Mahto, B. Samanta

"A heuristic model was developed to simultaneously generate the ultimate pit and production scheduling at a mining project. The method consists of a preprocessing step to select a starter pit, the implementation of a genetic algorithm to optimize the pit and schedule of the starter pit, and a network-flow algorithm–based postprocessing operation to finalize the ultimate pit and production scheduling. Applied to an iron ore mine, the model pit and schedule produced a net present value 21% higher than the reference pit and schedule prepared by experienced field engineers.RÉSUMÉ Un modele heuristique a ete developpe pour generer simultanement l’ordonnancement de la fosse finale et de la production dans le cadre d’un projet minier. Cette methode comprend une etape de pretraitement visant a selectionner une premiere fosse, la mise en oeuvre d’un algorithme genetique pour optimiser la fosse et le calendrier d’execution de cette premiere fosse, ainsi qu’une operation de posttraitement basee sur des algorithmes de flux reseaux pour finaliser l’ordonnancement de la fosse finale et de la production. En l’appliquant a une exploitation de minerai de fer, ce modele de fosse et d’ordonnancement a genere une valeur actualisee nette (VAN) superieure de 21 % a l’approche de reference pour la fosse et l’ordonnancement developpee par des ingenieurs de chantier chevronnes. INTRODUCTIONLong-term planning for an open-pit mine involves two important activities: developing the ultimate pit and determining the optimum production schedule. To accomplish this, an ore deposit is discretized into a number of smallsized elements called blocks, which are presented in a 3D block model structure. Because of economic and slope criteria, only a certain set of mining blocks can be extracted from the deposit constituting a pit. During mining, these blocks must be extracted in a specific sequence known as the production schedule."

Jan 1, 2017

By J. A. McLennan

Geological uncertainty is an unavoidable characteristic of all mining projects since only limited information is available from sampling. Mine planning and development decisions with significant economic consequences are made when the geological heterogeneity is inherently uncertain. Geostatistical simulation is preferred over kriging because the methodology provides alternative property realizations that can be combined into a model of geological uncertainty. Geological uncertainty can be transferred into production uncertainty, which can help characterize the economic risk of the project. This paper presents a case study for the Pogo property, being prepared for development near Fairbanks, Alaska. The exact dimensions, grades and production predictions have been modified; however, the methodology is illustrative. The geostatistical methodology consists of (1) assembling the relevant drillhole data and establishing a suitable coordinate system, (2) calculating the target distribution, (3) creating a model of spatial correlation, (4) generating multiple realizations at a small scale and (5) linearly averaging all the realizations to the chosen selective mining unit (SMU) support size. The geostatistical model is then used to calculate production uncertainty.

May 1, 2004

By K. Loutet, A. Guenkel, K. Nikolaisen

"The INCO SO2/air process was patented by INCO in 1985. Well over 80 mining operations worldwide are using this process to oxidize cyanides to cyanates in the tailings from gold, silver and copper mining operations. The sulphur dioxide (SO2) for this process can be supplied either as liquid SO2, SO2 gas or as a sulphite-based salt. The majority of SO2/air operations have used sulphite-based salts as the ‘SO2’ equivalent probably due to low capital cost. Liquid SO2 has also been used frequently, but due to concerns with safety and availability, this option is often not preferred. The solid salt sodium meta-bisulphite (SMBS) is commonly employed, but its cost is an order of magnitude higher than that of sulphur. Due to the high cost of SMBS, the increased capital cost for a sulphur-burning SO2 gas plant (green field or retrofit) usually has a pay-back of less than three years. In addition, a SO2 gas plant offers potential for significant heat recovery from the sulphur burning process. In terms of safety, the SO2 gas plant only requires the storage of relatively benign sulphur and the site inventory of SO2 will be limited to the plant gas volume. Therefore, a SO2 gas plant will not trigger the Canadian Environmental Protection Act (CEPA) E2 Regulations or the US Clean Air Act Section 112(r) accident prevention regulations, as may be the case for liquid SO2.Most existing mining operations using ‘SO2’ are gold operations, but in recent years there has been an increased interest in larger sulphur dioxide gas plants for hydrometallurgical facilities that employ leaching of cobalt/manganese minerals or precipitation of manganese/iron (e.g. Tenke Fungurume and El Boleo).This paper focuses on the production of sulphur dioxide gas generated on site and on demand for the use in hydrometallurgical processes. The capital and operational costs of a SO2 gas plant is compared to conventional process alternatives using sulphite-based salts or liquid SO2."

Jan 1, 2016

By M. Kumral, E. Dilhuydy, B. Ozdemir

"In-pit crushing and conveyor (IPCC) systems have become increasingly popular in the mining industry as an alternative to truck-and-shovel systems. Deciding whether to haul waste rock by truck or IPCC represents an important gap to be investigated in semi-mobile IPCC systems. A cost analysis is presented to evaluate the feasibility of crushing and conveying waste material in IPCC systems, along with sensitivity and risk assessments through Monte Carlo simulation. Although the capital expenditure is higher, results showed waste crushing will be feasible in deep pits and over long mine life and haul distances.RÉSUMÉ La popularité des systèmes de concassage et de transport dans la fosse minière (IPCC, de l’anglais In-pit crushing and conveyor) n’a cessé de croître dans l’industrie minière ; ils constituent en effet une option intéressante de remplacement des systèmes par camions et pelles mécaniques. Le choix entre le transport des stériles par camions ou par IPCC est encore difficile à faire et devra faire l’objet d’une étude approfondie au niveau des systèmes d’IPCC semi-mobiles. Une analyse des coûts est présentée pour évaluer la faisabilité du concassage et du transport des stériles par les systèmes d’IPCC, de même que des évaluations de la sensibilité et des risques par le biais de la simulation de Monte Carlo. Si les dépenses en immobilisations s’avèrent être plus élevées, les résultats ont cependant montré que le concassage des stériles sera envisageable dans des fosses profondes ainsi que sur une longue durée de vie et de longues distances de transport. INTRODUCTIONThe mining industry is currently facing many challenges such as low commodity prices, increasing environmental concerns and regulations, lower grades, deeper mines, and greater waste-rock quantities. As a result, the profitability of mining operations has decreased, with many mines stopping or suspending operations, and many new projects being postponed. Mining companies have therefore focused on improvements and innovations to increase the cost effectiveness of operations, for example, increasing production capacity to take advantage of the economies of scale (Crowson, 2003) and decreasing the unit operation cost. Changes in production capacity force mining companies to evaluate alternative material handling systems.During the past few decades and within material handling systems, significant improvements have been made to truck performance and capacity. Consequently, operating expenditures (OPEX) associated with fuel and maintenance have risen swiftly. In a mining operation, truck hauling systems now represent 40–50% of the capital cost and approximately 45% of the OPEX (Tutton & Streck, 2009). Additionally, material transportation costs are expected to increase due to longer haul distances arising from deeper and larger mines (Fleet et al., 2015). Finally, large fluctuations in fuel prices result in high risks associated with truck OPEX. According to the United States Energy Information Administration (2015), the cost of crude oil—the largest component of the retail price of diesel fuel—increased from US$24.31/barrel in 1986 to US$46.92/barrel in 2016, peaking at US$151.72/barrel in 2008 (Macrotrends, 2016)."

Jan 1, 2017

By Dan Alexander, Ivan Crnkovic, Sarah Schwarz

"Several plant studies have been conducted at the Zinifex Century Mine over the past 5 years. For each of the plant studies, surveys of the zinc primary circuit were conducted, characterisation measurements for each operating cell taken, and the floatability components of the ore mapped to develop a model of the circuit. The floatability components and machine parameters were then used to simulate changes in circuit configuration and operating conditions, enabling further potential improvements in circuit performance to be identified.This paper reviews the current flotation practice at the mine, as well as various circuit changes and developments implemented by site. The application of the methodology and the evolution of the standard procedure are also discussed.INTRODUCTIONBase metals were first discovered in the Lawn Hill region of Queensland’s North West in 1869 and the first mining lease in this area was pegged in 1887 over what is now known as the Silver King vein deposit. The area encompassing these veins, which includes the Century deposit, was proclaimed the Burketown Mining Field in 1899. Exploration titles were granted to CRA in 1987, precisely 100 years after the initial discovery at Silver King, hence the name ‘Century’.Century was commissioned by Pasminco in late 1999, with the mine becoming fully operational on 1 March 2000 and the official opening taking place in April. Pasminco had bought the Century and Dugald River deposits from CRA in 1997 for A$345 million, and invested some A$710 million in bringing Century into production. Today, Century is the world’s second-largest zinc mine in terms of its output, having reached full capacity in 2003.The Zinifex Century Limited (“ZCL”) lead-zinc-silver deposit is located approximately 250 kms north-north west of Mt Isa in north-western Queensland. The deposit is a large flat-lying ore body covering an area of some 1.2 by 1.4 km, the 45 m-thick stratabound sulphide orebody is hosted within an 850 m-thick sequence of Proterozoic siltstone, shales and sandstone, amenable to open-cut mining methods. The mine has ramped up to full production delivering five and a half million tonnes of ore per annum, yielding approximately 900,000 tonnes of zinc concentrate and 90,000 tonnes of lead concentrate. Mine life is expected to be about 8 years"

Jan 1, 2008

By Steve Wilkinson

"""Techniques for coarse-particle beneficiation of some gold ores and methods for determining potential for sorting any gold ore deposit.""With the advent of high speed computers, laser technology end different types of electronic sensing devices, ore sorting machinery has been developed, capable of handling significant tonnage rates while maintaining high level efficiency. Gold ores may be amenable to coarse-particle beneficiation where there exist measurable criteria upon which there can be recognition of auriferous versus barren lumps in the run of mine. Three types of criteria are suitable for sorting and are:i) Photometric - optical variance between ore and waste such as vein ores hosted by barren country rock;ii) Conductivity/Magnetic - based upon the metallic mineral content of ore end waste, and its association with Au, such as found in sulphide/arsenide Au ores,iii) Radtometric - detection of natural gamma activity occurring with uranium-bearirig gold ores.The method for determining the sortability of an ore depositconsists of, at least, three stages:i) Initial stage identification of ore and waste types,mineralogical/petrographical associations,amount of dilution in P.O.M.establishment of any sorting criteria]"

Jan 1, 1985

By A. F. Banks

"The last time I spoke to you the potash industry was at a low point. Markets were bad and the industry depressed. Many people had left and there was very little being done in terms of development. The current situation is very much changed. The oversupply conditions have given way to a very tight supply capability. All of the firms in the business are expanding in one way or another. These expansions will run from simple debottlenecking through to complete new projects.In New Brunswick, the Potash Corporation of America is proceeding with a new project and the Dennison - Potacan Project is in progress. In Saskatchewan, the Potash Corporation of Saskatchewan has an ambitious 2.5 billion dollar expansion program underway while those in the private sector are taking a somewhat less ambitious but equally significant approach to obtain further tonnage out of existing facilities.The significance of these expansions to mineral processors is that we can expect to see expanded employment opportunities and through necessity a surge in innovation and development in an industry that has been traditionally very conservative. This presentation will review potash processing with a view towards highlighting some of the more recent developments."

Jan 1, 1982

The Discrete Element Method (DEM) is a powerful tool for analysing the flow of charge, the energy consumption and the pattern of energy utilisation of a SAG mill. With the development of laser scanning measurement, the detailed internal working surfaces of a SAG mill can now be included in DEM models. Using scanned results for new and worn shell liners for a 32? (9.75 m) SAG mill, it is shown that the feed and discharge lifters have significant effect on the flow of the charge introducing significant threedimensionality. The effects of the resolution accuracy of liner geometry and the lower cut-off of the rock size distribution are explored. Finally, using a matched new and end of life worn liner and operating conditions taken from site surveys, the effect of wear on charge motion, distribution and energy utilisation are evaluated.

Jan 1, 2012