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By Claude Bazin

"Laboratory semi-batch flotation tests were conducted using two different sulphide ore samples. The size reduction was adjusted to cover a wide range of flotation feed size distributions. Results show that similar recoveries can be achieved independently of the fineness of grind. This result suggests that possible energy savings could be achieved by a redistribution of the power between the grinding and regrinding mills. The behaviour of the selectivity curves shows that some gangue minerals are more sensitive to particle size than other ones, implying the existence of preferential associations between minerals in the ore.INTRODUCTIONInteractions between grinding and flotation have been studied for many years, and still a robust model to link the two processes lacks to be developed (Girard et al., 2005; Bazin et al., 2001). The ore size reduction liberates mineral grains, while flotation separates them into valuable minerals and gangue. The more size reduction that is applied to the ore the more important is the mineral liberation but also the production of fine particles that can pose problems during flotation (Trahar and Warren, 1976). The definition of the grinding requirement for flotation is a complex problem (Rickelton and Dell, 1977; Sosa Blanca et al., 2000; Morrison, 1993; Wei and Gay, 1999).This paper analyzes the effect of the fineness of grind using semi-batch flotation test results. The first two sections describe the test procedure and the results. The third section analyzes the results in terms of liberation and selectivity, and proposes a possible redistribution of power between grinding and regrinding mills."

Jan 1, 2006

This paper focuses on the dissolution of various Manganese based compact additions into liquid Magnesium. The experimental procedure employed cylindrical compacts with various Manganese compositions. The various temperatures of the additions and the Magnesium bath were measured simultaneously during the immersion of the additions into Magnesium bath. The exothermicity level of these additions during their dissolution into liquid Magnesium was determined. The relation of the exothermicity level with the dissolution kinetics was also examined. In addition, SEM and EDX work was conducted for additions, which were withdrawn from the Magnesium bath. Finally, the recovery of these additions was estimated by taking samples from the Magnesium bath and conducting ICP analyses.

Jan 1, 2006

By Cecilia Arrue, Dominic Fragomeni, N. O. Lotter

"A statistically designed benchmark mill survey was carried out in July 2005 at the Kidd Creek Concentrator, D Division circuit, which processes Ni/Cu ore from the Montcalm deposit. A structured statistical survey approach was followed, together with defined quality controls, which would assign a 95 percent level of confidence in the result.A set of six surveys were completed over a limited time; the corresponding stream samples of the surveys found acceptable were combined to obtain high confidence composite samples. The head grade of each survey is compared to two distributions to test its acceptability; surveys that fail to conform to these trials are rejected. The accepted set of surveys, which is a robust representation of the process, is prepared into a composite for QEM-SEM analysis and mass balance purposes.Where the above practice is a standard procedure in Falconbridge for QEM*SEM purposes, in this case each individual two-hour survey unit was measured and analysed for a mass and value balance. It is shown that none of the individual mass and value balances close as well as the composite set of accepted two-hour survey units. This founding is in keeping with the averaging properties of the Central Limit Theorem.INTRODUCTIONMontcalm OperationsNi/Cu bearing ore from the Montcalm deposit is being processed at the Falconbridge, Kidd Creek Concentrator in a modified D Division circuit. The circuit was commissioned in the fall of 2004. Ore is crushed at the minesite to –19 mm and trucked to Kidd for delivey into the 4 parallel fine ore bins.Ore is milled in a rod mill followed by cyclones and 2 parallel ball mills. The grinding circuit treats Montcalm ore at an average feed rate of 100 wet tonnes/hour (750,000 tonnes/annum) and produces a flotation feed particle size of 83% -53 um. A simple flowsheet including bulk Cu/Ni roughing and 2 bulk cleaning stages followed by Cu/Ni separation in 2 stages is practiced. Soda ash is used as a pH modifier in bulk flotation. SIBX is the collector. Lime and Dextrin are added into Cu/Ni separation for the depression of pentlandite."

Jan 1, 2007

"INTRODUCTIONGold tailings retreatment plants have been operated for many years throughout the world. Several large tailings retreatment facilities have been operated profitably in South Africa since 1976 and there are tailings retreatment operations in Canada currently in production with more in the feasibility stages.The Timmins Gold Tailings Project of ERG Resources Inc. was designed to treat 8,000,000 tonnes per annum of gold tailings for an eight month operating season, and commissioning of the operation began in July 1988. The payback period for this project is about 3 years which corresponds to an IRR of 30%.This report summarizes the metallurgical characteristics of the reclaim tailings, describes the process flowsheet which was developed to enable ERG to economically recover gold from the Timmins area tailings, and reviews commissioning activities."

Jan 1, 1989

By Steve McAlister, Colin Sprake

"Enhanced gravity concentration machines have been applied successfully in the following areas of precious metal recovery flowsheets:1. Primary Grinding Circuits2. Shaking Table Tailings3. Pre-Concentration of Leach Feed4. Flotation Concentrates -•, Flash•, ConventionalAlthough great progress has been made, the ability to produce directly smeltable concentrates still remains elusive. Even without this ability, centrifugal concentrators are finding wideningapplications in precious metal concentration:1) PRIMARY GRINDING CIRCUITSEnhanced gravity concentration technology has largely replaced jigging as the technology of choice in precious metal grinding circuits worldwide. The benefits of using a centrifugal field to concentrate both coarse and fine gold are well documented but the placement of these machines within grinding circuits is still evolving. Conventional wisdom dictates that the best location for enhanced gravity machines is cyclone underflow on account of the elevated grade found in this stream when compared to cyclone feed or overflow. Plant operating experience at both large and small scale indicates that there are compelling arguments to place ENHANCED GRAVITY MACHINES on cyclone feed instead. At least two new plants, presently in the detailed design stage will incorporate gravity circuits that treat mill discharge or cyclone feed, Teck Cominco’s Pogo and Newcrest’s Telfer Expansion.Current Conventional PracticeThe current stream of choice for enhanced gravity concentration within grinding circuits is cyclone underflow although recent information indicates a swing toward cyclone feed. Here are some of the arguments for treating a portion of cyclone underflow:"

Jan 1, 2003

By Iwueze Anaekperechi Rose

The International Labor Organization has declared mandatory adequate provision of safe workplace and safety for all workers in all occupations including the mining sector. Early scientists like Agricola (1559) who studied the health of Miners, found that there are peculiar health problems associated to their work and working environment. This unsafe working condition was one of the major factors that resulted to the Industrial revolution in England and eventually led to the establishment of regulations and laws guiding operations in all workplaces and workers in England and all over the world. Recent studies by Heinrich suggested chains of events of safety issues in the mining sector. Occupational injuries, accidents and ill health have huge social and economic implications on workers, their families and communities. Top mining top issues are respiratory diseases, noise, explosives, ventilation, fire, and explosion. However, one of the principal mechanisms for achieving Occupational Health and Safety (OHS) goals and mapping the future is government regulations of employers. In Nigeria, the situation is not different; mining operations are equally hazardous and have far reaching implications. In 1995 the Ministry for Solid Minerals was established to focus on the development of other categories of mineral products ranging from gold, coal, uranium, and tantalum deposited across the country. Prior to this an Act of Parliament Act Cap 121 of 1946, was in place to regulate amongst other contents mining safety. This was subsequently reviewed following the incidence of Lead poisoning resulting from small scale miners processing gold ore highly contaminated with lead in Zamfara state (northern Nigeria). Hundreds of children died as a result of exposure to lead poisoning, it was clear that the regulations were not sufficient (details to be discussed). However, advances have been achieved in mining engineering since then. A review team was constituted to provide a more stringent law to regulate mining operations in Nigeria. The strategies for mapping the future of OHS in mining engineering will employ amongst others setting and adopting ISO/ILO standards and enforcement; providing technical assistance; and establishing sustainable developmental structures as surveillance and compensation. The management systems approach was also developed as a result of cases of accidents. The accepted international standards guidelines and requirements will be proposed. Furthermore in mapping the future for Mining Engineering, it is suggested that most countries have their own management strategies and legislation to improve safety of workers through greater consistency and efficiency of OHS programs. Some American researchers came up with the Safety Engineering Model. The Australian Mining Council of mineral and petroleum resources after the Catastrophic Maura Disaster developed the National Mine and Safety Framework. In Canada, after the Hillcrest mine disaster in 1914, Allan shaft coal mine catastrophe in 1918, Westray mine explosion in 1992 and other disasters, Occupational Health and Safety Act R.R.O 1990 was sufficiently developed to provide adequate safety conditions and standards. In Nigeria after the disastrous Zamfara lead poisoning, which claimed the lives of hundreds of children due to exposure and lack of appropriate safety measures, stringent measures were developed by the federal ministry of Justice to address and regulate mining process in Nigeria.

Aug 1, 2013

By Julie Culverhouse, Dennis Grimm, Kieran Harding, Jean-Francois Boulanger

"Agrium’s Canadian Phosphate Business (CPB) is comprised of Kapuskasing Phosphate Operations (KPO) in Northern Ontario, Canada’s only operating phosphate mine, and Redwater Phosphate Operations (RPO) in Alberta, which manufactures the fertilizer from KPO’s concentrate.Production from KPO’s South Pit commenced in 2009 and introduced contaminant problems: high aluminium from crandallite and kaolinite clays. These issues caused a drastic decrease in P2O5 recovery and throughput in both plants. KPO attempted to reduce Al clays by means of aggressive desliming. Meanwhile RPO experienced high amounts of dissolved metals in their feed that are detrimental to fertilizer production.This paper covers the mineralogy of the problem, its impact on contaminant separation at KPO, on RPO’s process and on Agrium’s Canadian Phosphate Business as a whole.Potential solutions to the problem are discussed and analysed, including a process change to deslime high aluminium streams more aggressively and high grade ore flotation, which is atypical at KPO. The latter is a demonstration of the value of communication between the concentrator and the client, as KPO accepted a recovery loss and increased production costs in order to increase overall CPB profits. General lessons learned are discussed, followed by a section on ore blending.INTRODUCTIONAlthough the existence of the Kapuskasing phosphate deposit has been known since the 1970s, it’s only since 1999 that Agrium has been operating the Kapuskasing Phosphate Operations (KPO). The mine consists of three major pits (Center, North and South) from which a mining contractor hauls the apatite ore to the Agrium concentrator. The beneficiation plant processes the ore, separating contaminants such as Fe, Mg and Al which are detrimental to its client, Agrium’s Redwater Phosphate Operations (RPO). The KPO concentrate is finally thickened, filtered and dried before being shipped by rail to RPO.At the Redwater plant, the KPO concentrate is added to a sulfuric acid solution in an attack tank, to create a phosphoric acid solution and gypsum:"

Jan 1, 2011

By S. Schwartz, T. Bilney

"Over recent years a number of techniques have been developed as part of the AMIRA1 P9 project to represent mathematically or measure directly sub-processes occurring in flotation cells. These include the determination of:•,?a machine parameter (bubble surface area flux, Sb);•,?a froth parameter (froth recovery, Rf );•,?entrainment and drainage parameters (???and d); and•,?an ore floatability parameter (Pi).These flotation parameters allow the plant engineer to develop a model of the flotation circuit that can be used as a powerful tool to diagnose the performance of that circuit. The recently developed JKSimFloat V6 flotation simulator uses these parameters to predict the flotation circuit performance that would arise from changes in operating conditions and circuit configuration.This new flotation technology was applied to the Placer Kanowna Belle Gold Mine in Western Australia. A series of plant surveys, cell characterisation measurements and laboratory batch tests were conducted to determine the flotation circuit model parameters to be used within the JKSimFloat V6 simulatorA thorough flotation circuit analysis was then performed at Kanowna Belle using JKSimFloat V6. The recommendations that were provided by this circuit analysis have resulted in large improvements in the flotation performance at Kanowna Belle. These include a 1.3% increase in flotation gold recovery and a substantial decrease in operating costs. The analysis is still ongoing, however, the benefits already obtained from applying this technology have resulted in a US$1.3 million a year improvement to the mine."

Jan 1, 2005

By Elmer Palmer

As part of the Goldcorp Inc growth plan Minera Peñasquito SA de CV has developed its polymetallic deposit with a large ?state of the art? concentrator to process lead and zinc ores. The plant consists of two grinding lines including 38ft diameter SAG mills and 24ft diameter ball mills. During mid to late 2009 concentrator commissioning activities commenced. First concentrates were produced in October 2009 and now the plant is meeting its design basis of 65,000 mtpd per line. This paper describes the design and operational experience to date for its grinding circuit design, together with the recently commissioned HPGR crushing circuit.

Jan 1, 2012

By Xie Qiang

It is known that the stress state inside rock discs under Brazilian tests is neither simple compression nor tension, but a complex combination of both stress types, as well as for a beam subjected to bending, where compressive and tensile stresses are separated by the neutral axis. In this study, AE generation was obtained on pure white marbles from south Portugal that were submitted to both Brazilian and bending tests. Main questions to be answered were: (1) Does Kaiser effect exist in tests which create complex distributions of tension and compression? (2) Are there any meaningful differences in AE behavior of marble under Brazilian and bending tests?

May 1, 2009

By R. J. McLeod

"CONTROL STRATEGYThe Lake Dufault Division of Falconbridge Copper Limited has been concentrating a complex copper zinc ore since late 1964. An ARL X-ray on stream analyzer was installed in 1966 for process control. A Digital Equip-ment Corporation PDP8 was added in 1968 for more complete control. To improve the system the computer was exchanged for a Moded PDP-81 in 1971.The new computer is time sharing with 8K core memory and 32K disc storage. A new interface was installed to accommodate 14 X-ray streams and additional analog signals for process control. The system gave us additional capacity and flexibility to make changes in operating programs and control strategy while on line. As the computer is used for process control a modified focal language was chosen as the operating language for ease of operation. This language is more suitable for process control than for statistical work.The main components of the control system are(a) Computer(b) Interface(c) Production Control X-ray Quantometer(d) Teletype terminals(e)Reagent feeders(f) Sample SystemThe operation of the system consists in the computer selecting the various streams to be analyzed by a PCXQ Quantometer. When the flowing sample is presented to the X-ray the intensities of the various elements are read by the computer from analog to digital converter, the assays are then computed. From the tonnage and assays the computer is programmed to determine the amount of reagent added to various parts of the circuit. The computer drives the feeders via the interface for the required amount of reagent. After following a certain sequence the computer prints out the performance and control data on an ASR35 Teletype. The data is printed out approximately every seven minutes. Any des¬ired changes in the program or strategy can be made during operation via an ASR33 Teletype connected to the computer."

Jan 1, 1973

By Christoph Miller

About 80 years ago the mining industry saw an advertisement of a machine manufacturer: ?One man ? one machine?, meaning the productivity gain by using a pneumatic rock drill instead of manual tools. Mechanization in mining had started. In the 1950's and 1960's when mechanization progressed the word could be transformed into the meaning of ?one man ? one drill rig?. During the 80's automatic functions were added to the machines. Automation started. In the 90's, the first autonomous machines were seen, transforming the advertisement from the 1920's into ?one man ? multiple machines? operated from a remote control room. Soon, the productivity gain achieved by pure automation will also be flating out meaning that the margin cost of further productivity gain will be inefficiently high. What next? In mining operations there is still a high potential of unused productivity lost by ?trivial? things like organization, logistics and operational management. Changing the focus from mechanization and automation towards optimizing the overall mining process will unleash another big potential for cost cuttings and for enhancing efficiency of production. Optimizing an overall process is a task of much higher total complexity compared to an isolated machine automation focus. And a successful process integration requires the collaboration of machine vendors, infrastructure suppliers, IT services and the mine itself. It requires a number of of important preconditions to be fulfilled: ? Integrated IT systems with seamless interfaces between all components and peripherals involved ? Real time information access in all locations ? Real time overview of all operational aspects A crucial aspect for all of these issues is a seamless communication both above and also under ground and IT interfaces which are easy and price efficient to implement. This paper highlights ways to achieve productivity gains by process optimization. It also discusses needs for industry wide activities in order to enable cost efficient performance of mine process optimization projects.

Oct 1, 2009

By Daniel Hodouin, Claude Bazin, René del Villar

"A traditional linkage has long been established at Laval University's Department of Mining & Metallurgy between the Mineral Process (MP) and the Mining Exploitation (Min) on one hand, and between the Extractive Metallurgy (EM) and the Materials Engineering (Mat) on the other. This academic separation of Mineral Processing from Extractive Metallurgy at the educational level has become increasingly at odds with today's industrial practice in which both disciplines are not only complementary but also often intertwined. For instance, in gold ore processing, comminution, flotation, and gravity separation units are interfaced with atmospheric or pressure leaching modules and with carbon adsorption and electrowinning units. The new copper plants in South America combine comminution and flotation circuits with heap leaching, solvent extraction and electrowinning processes.In order to reflect this new industrial reality and to harmonise the options offered in both its engineering programs, the Department of Mining and Metallurgy of Laval University has introduced major changes in its curriculum in 1996. These changes reflect also the recognition that the somewhat secondary status given so far to Mineral Processing and to Extractive Metallurgy within their ""mother"" programs, Mining/Mineral Engineering and Materials metallurgical Engineering respectively, was in sharp contrast with their actual significance for the Canadian economy. Leading industrial voices have raised similar concerns and the Canadian Engineering Accreditation Board has also addressed this problem in its latest program evaluation.The changes implemented at Laval aimed at a) better representing MP and EM within the two undergraduate programs; b) training top-level versatile and multidisciplinary engineers, fluent in all aspects of MP and EM, irrespectively of which of the two ((mother)) programs they had chosen and capable of meeting today's industrial requirements; c) training students in process analysis, optimisation and automatic control using state-of-the-art software, and d) taking into account the co-operative nature of both undergraduate programs.Results are very encouraging in terms of student enrolment and industrial response. However, some concern is expressed on the sustainability of the renewed curriculum considering the drastic budget restrictions in effect at Laval as in most other Canadian universities."

Jan 1, 1999

"4.1. IntroductionThis chapter reviews the geochemistry of the platinum-group elements (POE) in sulphur-poor silicate rocks, and the limited data on POE in silicate, oxide, sulphide, arsenide and sulpharsenide minerals. The earliest geochemical studies of POE in silicate rocks, minerals and meteorites were carried out mainly by Goldschmidt, the Noddacks and their co-workers, and are reviewed in Crocket (1969). These researchers established the siderophile character of the POE, emphasized the common association of the group with sulphides in ultramafic-mafic rocks and suggested that very low concentrations of POE are typical of sulphur-poor silicate rocks and minerals. Much of these data were for Pt and Pd only and are more than 50 years old. Because of the poor sensitivity typical of the available analytical methods, few reliable data were obtained on silicate rocks in these early studies. Surveys of POE geochemistry demonstrate that the data base for sulphur-poor silicate rocks is very restricted, although considerable highquality data for Pd and Ir have been accumulated (Wright and Fleischer 1965, Yushko-Zakharova eta/., 1967, Mertie 1969, Crocket 1969, 1979, Keays 1981).Two recent publications, Vol. 71, No. 7 (1976), of Economic Geology (An Issue Devoted to Platinum-Group Elements) and Vol. 17, Part 2 (1979), of The Canadian Mineralogist (Nickel-Sulphide and Platinum-Group-Element Deposits), are of special interest. These volumes are clear testimony to the impressive progress made in the last decade toward describing the mineralogical and geochemical aspects of POE ore deposits, but at the same time demonstrate the constraints in modelling POE ore genesis due to our meager knowledge of the. POE content and distribution among minerals in the source rocks of ultramafic and mafic magmas. It is clear that the phases hosting POE in mantle source rocks are poorly understood. Nevertheless, Naldrett and Duke (1980) have shown that the absolute and relative concentrations of POE in magmatic sulphide ores are related to the degree of partial melting of mantle peridotites, and subsequent processes of batch equilibration and fractional segregation of sulphides."

Jan 1, 1979

By Rodolfo Espinosa Gómez

"Industrias Peñoles, S.A. de C.V. – Mining Division, has initiated in the last ten years, six Mining Operations (Bismark, Tizapa, Ciénega, La Herradura, Rey de Plata, and Francisco I. Madero) and it has expanded several of their existing Operations (Sabinas, Fresnillo, Tizapa, Ciénega) one or more times.This work aims to share the experiences learned on this growing process. Some of these lessons are: 1) Project leaders must have a leadership that fosters good communication and team work; and this leadership style must come from top management. 2) A good communication must exist between the personnel from Engineering, Construction, and Operation. Also, this good communication must come from top management. 3) Starting the project with a solid Engineering Study. 4) Do not misunderstand cost with cost/benefit; always look at the cost/benefit. 5) Selecting good Contractors and good Suppliers. 6) Good training before the project commissioning is essential to reduce the learning curve period, this is even more important in areas where local people do not have any background in mining activities. 7) Recognizing that any project has a learning curve and it must be reflected on the production budget. 8) Avoid an over optimistic Mine preparation time schedule.BACKGROUNDIndustrias Peñoles S.A. de C.V.The mission of Industrias Peñoles, S.A. de C.V. (Peñoles) is to add value to non-renewable natural resources in a sustainable manner. Peñoles seeks to build long-term shareholder value; provide their customers with the highest quality products and services; maintain productive longterm relationship with their suppliers; develop and promote the capabilities of their personnel; foster mutually beneficial relationship with the communities in which it operates, and preserve the environment.Peñoles was established on 1887. It is a Mining Group with integrated Mining, Smelting and Refining operations of non-ferrous metals, and also produces inorganic chemistry materials. Peñoles is the main World producer of refined silver, metal bismuth, and sodium sulphate; Latin American leader in the production of refined gold, lead, and zinc.The Mining Group is made-up of nine mining operations producing concentrates with high gold, silver, lead, zinc, and copper contents. It produced in 2002, 365,900 ounces of gold; 52.7 million ounces of silver; 86,820 tonnes of lead; 266,000 tonnes of zinc, 11,840 tonnes of copper; with a total values of 3,780.6 million of Mexican pesos (~ $ 378.0 million U.S. Dollars)."

Jan 1, 2004

By R. E. MacAfee

THERE have been great changes in the design, capacity, and pressure of steam generating units over the past fifty years. If we go back as far as 1890, the plants then existing were largely horizontal return tubular boilers, hand-fired, with the boilers supported on the brick sitting which was com-posed of red brick with, probably, a refractory lining one brick thick in the combustion chamber. About this time, the water tube boiler began to supplant the H.R.T. boiler and, where new plants were being constructed of any size, water tube boilers were largely installed. In those days, say from 1890 to 1905, a 250 h. p. water tube boiler was considered a large unit. These boilers were largely the straight tube type and were set with the first row of boiler tubes three to six feet above the grates. The brick setting was a combination of red brick and fire-brick. The fire-brick lining in the furnace proper was usually 9 in. thick and in the first pass 4 1/2 in., while the rest of the setting was entirely red brick. These units were largely hand-fired and were expected to produce about 100 per cent rating as a maximum. It may be well at this point to define rating, which is the evaporation of one boiler horse power per hour by each ten square feet of heating surface in the boiler. A boiler horse power is the evaporation of 34.5 pounds of steam from and at 212°F. Consequently, a boiler containing 2,000 square feet of heating surface is rated at 200 h. p. and the evaporation at 100 per cent rating is 200 X 34.5, which equals 6,900 pounds of steam per hour from and at 212°F.

Jan 1, 1939

By M. Gaumont, F. Robichaud

"Agnico Eagle Mines Limited (AEM) is a Canadian-based gold producer with operations in Canada, Finland and Mexico. In 2010, AEM produced its first gold bar in Nunavut, Canada as it started its Meadowbank operation. It is also in 2010 that AEM acquired the Meliadine property, which is located 25 Km North of Rankin Inlet, Nunavut, Canada. The Meliadine gold project is an advanced exploration and development project, comprising of workers camp, underground and open mines, a processing plant and all the services facilities and infrastructures required to sustain operation in a remote arctic environment.Pending formal board approval, production start-up is planned for Q3 2019 and the process flowsheet is based on an ore processing rate of 1.1 million dry tonnes per year (3,000 dry tonnes per day from underground mining) for the first three years, and 1.98 million dry tonnes per year (5,000 dry tonnes per day from both underground and open pit mining) for the remaining years at 92% process plant availability.To the end of 2015, more than 45 metallurgical test programs have been conducted on the Meliadine deposits. Based on the results of these programs, an optimal gold circuit was designed, comprising of crushing, grinding, gravity separation and cyanide leaching with a carbon-in-leach circuit (CIL), followed by cyanide destruction and filtration of the tails for dry stacking. The assumed gold recovery for the reserves averages 96.0% at a 7.44-g/t gold average mill feed grade."

Jan 1, 2016

By J. Kazakoff

"The success of gold recovery at the Jolu gold mill depends on many variables. The most important ones are the people, the ore body, plant design parameters, equipment selection and cost control. This paper will briefly hiqhlight the above, the main focus, however will be on the gravity gold circuit.The gravity circuit requires judicious operator attention in order to operate properly. In return the circuit gives immediate visual results for mill peopleIntroductionThe development of the Jolu property to the production stage was carried out quickly, efficiently and economically. The property became a gold producer ahead of schedule and under budget.The Jolu property is a joint venture between International Mahogany Corp., a 70% partner, and Corona Corporation, a 30% partner. Corona Corporation operates the Jolu Gold Mine, located 140 kilometers north of LaRonge and 520 kilometers north of Saskatoon."

Jan 1, 1990

By Tony Lipiec, Greg Gosson

"When it comes to new mines being developed, there is a general industry consensus that most low-hanging fruit has been picked. Many projects currently in the mine development pipeline have been around for decades, but were held back because of technical challenges. Future development of these deposits will likely require access to the public capital markets, and in Canada that means providing scientific and technical disclosure on these deposits in compliance with NI 43-101. As many of these “challenged” projects have metallurgical issues, the companies that own the projects need to ensure their metallurgical Qualified Persons provide transparent disclosure regarding proposed solutions to those issues.This paper provides an overview of the disclosure requirements under NI 43-101 that are pertinent to metallurgists, and other Qualified Persons who prepare technical disclosure regarding the metallurgical characteristics of a mineral project. It lists the triggers for a technical report under NI 43-101 and Canadian stock exchange policies, and identifies the sections of the report that should involve input from a metallurgist or process engineer. It briefly outlines new civil liabilities under Canadian securities laws that increase the possible consequences for not complying with the technical disclosure standards.These materials are provided for general information purposes only and do not constitute legal advice. Readers are advised to seek specific legal advice from their own legal counsel in relation to any decision or course of action contemplated."

Jan 1, 2010

By P. Wells, P. Quinn

"A moveable flotation miniplant was designed and constructed at the research laboratory of Inco Technical Services Ltd. to address the need for flowsheet development with a limited amount of ore (such as drill cores). It consists of one rod mill, two regrind ball mills, one vibratory screen, 24 flotation cells of various sizes and two Venturi aerated flotation columns. The setup has continuous monitoring capability for pH, dissolved oxygen, oxidation-reduction potential, conductivity and temperature in conditioning tanks and flotation cells. Various options regarding flotation reagents, circuit configurations, and fineness of primary grind and regrind can be readily evaluated. The throughput of the miniplant is 20 – 30 kg/hour ore.Unit operations such as flash flotation, magnetic separation and gravity concentration can also be evaluated as an integral part of an entire flowsheet development.This communication describes the basic design features of the miniplant and some examples of applications are given.INTRODUCTIONInco operates numerous mines in Sudbury and Thompson and will shortly bring the Voisey’s Bay mine into production. It has long been recognized that the ores from different mines or from different depths of the same mine can give different responses in flotation. There is a growing need to properly evaluate the ores before feeding the mill to maximize the return of the mine/mill operation. Inco Technical Services Limited at Sheridan Park, Mississauga, Ontario has developed a batch laboratory procedure to address this issue. The results are considered in the overall economical assessment of new mine operations.For ores that cannot be processed by the existing mill operations or that will be processed by a new mill, it is necessary to develop a flowsheet that can maximize the economical return of the mine/mill operation. While recognizing the importance and contribution of the laboratory batch flotation procedure, it does not generate reliable data for flowsheet simulation and design. A full-scale pilot plant campaign is normally required to obtain the design data but often this is not possible due to a limited amount of ore obtainable from the drill core. A small-scale pilot plant (mini pilot plant or miniplant) capable of processing 20-30 kg/h ore can provide this data prior to a full-scale pilot plant campaign. A miniplant can also be used to optimize the circuit configurations, reagent additions and recycle options of process water before pilot plant work and can be used to test a different flowsheet configuration for an existing mill before re-piping a plant circuit."

Jan 1, 2003