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By Rudy Tenbergen, Dick Farmery, Jim Naylor

"Paste backfill has replaced cemented rock fill as one of the components to improve ground · control and mine safety at the Macassa Operation of Kinross Gold Corporation in Kirkland Lake, Ontario. It is the first operation to utilize "" flash thickening ""of very fine gold tailings to a paste consistency in the ""Paste Production and Storage Mechanism"", a joint technical development of Inco and GL&V. The tailings paste is mixed with alluvial sand to produce an engineered quality paste backfill. The development leading up to the decision to proceed with this novel technology is discussed, as well as commissioning of the backfill operation.IntroductionThe occurrence of a major rockburst on November 23, 1993 prompted a review of mining and backfill procedures at the Macassa No 3 shaft . This shaft is some 7238 ft deep and lies in a mining belt that is prone to seismic events. The recommendations were to change the mining from underhand cut and fill to mechanized long hole stopping and to look at alternatives to the rockfill backfill system in place. The Macassa cemented rock backfill operation, while producing the desired fill stiffness had drawbacks as compared to paste fill. With paste fill, placement rates are faster, more openings can be filled, it is less expensive and less prone to the occurrences of compensable incidents.Macassa mining personnel visited the Sudbury operations of Inco in 1993, where development on paste backfill was in progress. As some of the R&D was taking place with funding from the Premier's Council Technology Fund of the Ministry of Trade and Technology of the Province of Ontario , Inco personnel at that time did some feasibility and conceptual consulting on the use of paste fill for the industry. Inco had developed the use of alluvial sand paste fill, an engineered blend of alluvial sand and tailings fines and was doing development work to eliminate the ""conventional"" way of producing paste from mill tailing by thickening and filtration. This latter development work was taking place with GL&V Ontario. That work led to the filing of a joint Inca/ GL&V patent application for the PPSM, the Paste Production and Storage Mechanism with all marketing rights being held by GL&V."

Jan 1, 1997

By Derek H. C. Wilton

"The Nain Province (NP) of northern Labrador is a >600 km long by =100 km wide Archean craton that has undergone relatively little mineral exploration until economically signifcant concentrations of orthomagmatic nickel sulphide were discovered by Diamond Fields Resources (DFR) at Voisey’s Bay. Due to the great time span between crust formation andfnal intrusive activity (ca. 3.9 Ga to 1.27 Ga),there were, however, numerous metallogenic events within the NP.The NP was intruded by the ca. 1.3 Ga to1.2 Ga Nain Plutonic Suite (NPS) composite anorthosite-granite complex. The NPS dividesthe NP into the southern Hopedale Block (90 km by 150 km) and the northern SaglekBlock (375 km long by =50 km wide). These two blocks appear to represent two distinct Archean cratonic nuclei, each with its own distinct metallogenic history. The NPS is a coalesced assemblage of composite intrusions which include anorthosite, troctolite, norite, gabbro and granite.The Hopedale Block contains the Hunt River and Florence Lake greenstone belts, and the Weekes Amphibolite which represents remnantsf the older Hunt River greenstone belt. Geologically, these belts have some potential to host komatiitic Kambalda-style nickel, volcanogenic massive sulphide (VMS) and meso -thermal lode gold mineralization. The unconformity between Paleoproterozoic cover sequences and the trondhjemite-tonalite-granodiorite (TTG)suite which engulfed the greenstones was the locus for lead-zinc-bearing quartz-carbonate veins. Minor fracture-hosted uraninite showings are also present in the TTG.The Saglek Block is a high-grade gneissterrane with deformed Archean supracrustal sequences but no greenstone belts. Within the gneiss are variably-sized enclaves that range in composition from anorthositic to ultramafic; some of these latter xenoliths contain abun-dant fuchsite. There are also three small anorthositic to ultramafic meta-igneous complexes present in the gneiss near Okak Bay.Some Archean meta sedimentary and maficgneiss supracrustal sequences contain iron-oxide and sulphide members. The sulphide-bearing Tasiuyak parag neiss defines the cra-tonic suture between the NP and Churchill(Rae) Province. Along the cratonic suture between the NP and Churchill Province from Ramah Bay north are remnants of the Archean(or Paleoproterozoic) Hutton Anortho site Suite. Ultramafc layers within the suite contain chromite and elevated Ni values.Three ca. 2.0 Ga supracrustal sequenceswere deposited in small fault-bounded basins within the NP. The Snyder Group contains pyrrhotitiferous massive sulphide horizons. TheMugford Group contains SEDEX-like massive sulphide blocks in a debris fow and ultramafic sills with unusual PGE concentrations; alaskitic granite cutting basement gneiss to the group contains stockwork-like pyritiferous quartz veins. The Ramah Group contains numerous MVT-style zinc-lead sulphide occurrences.The Reid Brook Intrusion of the NPS contains enormous and high-grade nickel-copper-cobalt massive sulphide bodies at the Voisey’s Bay deposit. Exploration in the northern portions of the NPS in 1995 has indicated the presence of other potentially economic nickel sulphide horizons."

Jan 1, 1996

By T. Hadley, E. Catovic

"Northern Minerals Limited’s (ASX: NTU) flagship project is the Browns Range Rare Earth Project (the Project) located in Western Australia, consisting of a number of deposits with high value, heavy rare earth elements, in particular yttrium, terbium, and dysprosium. The deposits are dominated by xenotime mineralisation, which occurs within hydrothermal silicified and hematitic breccias. The Company delivered an initial JORC compliant resource estimate for the Project at the end of 2012 of 10,500 t of contained total rare earth oxides (TREO), which was increased to 28,084t of contained TREO in October 2013 and further enlarged to 47,997 t of contained TREO in February 2014. Concurrent with the growth of the Project resource base, significant progress has been made in developing the metallurgical process for the beneficiation and extraction of rare earth elements (REE’s) from the xenotime mineralisation. Development of the beneficiation circuit evaluated several process options and selected whole-ore flotation and magnetic separation, followed by flotation (hybrid circuit) as the two preferred flowsheets to pilot, following encouraging results on the bench of 83% and 86% recovery to a 20% TREO mineral concentrate respectively. Several downstream hydrometallurgical extraction flowsheets were evaluated. However, the following two preferred process flowsheets were ultimately selected for further detailed investigation during the prefeasibility study: 1. Sulphation bake, water leach, purification, oxalate precipitation, and/or calcination to produce a mixed RE oxide; 2. Sulphation bake, water leach, phosphate precipitation, caustic conversion, HCl leach, and oxalate precipitation to produce a mixed RE oxalate. Excellent heavy rare earth oxide (HREO) extractions (~ 90%) from beneficiation concentrates were achieved on the bench for both circuits, however flowsheet 1 was ultimately selected as the preferred flowsheet to pilot due to lower capital and operating cost. A mixed rare earth oxalate (42% TREO) or oxide (92% TREO) can be produced with low levels of Th and U of 3 ppm and 6 ppm respectively."

Jan 1, 2014

By Turcotte. Yves-Laurent

Notre conférencier, Monsieur Yves L. Turcotte, Vice-président et Directeur général chez Promaintech Novaxa est diplômé en génie industriel de l?Université du Québec à Trois-Rivières et détient une maîtrise en gestion de projets de l?Université du Québec à Montréal. Il est une véritable sommité canadienne dans le domaine de l?amélioration de la performance des organisations. Provenant d'entreprises manufacturières et de services, il possède plus de 20 ans d?expérience en tant que développeur de technologies, conseiller et formateur auprès d?entreprises. Il a à son actif la réalisation de mandats dans plus de 400 entreprises. Il est reconnu pour sa grande capacité d?analyse et pour trouver des solutions novatrices et profitables aux problèmes des organisations les plus complexes. Aujourd'hui, il dirige Promaintech Novaxa, une division de DMR, qui a célébré son dixième anniversaire en 2006. Cette organisation ayant des places d?affaires dans la région de Montréal, Québec et Vancouver compte plus de 50 professionnels et a une carte de visite dans 16 pays. Les axes d?intervention sont le Management, la Productivité, la Fiabilité, l?Innovation et l?Amélioration Continue.

Feb 1, 2008

By Paul Miranda, Corby Anderson

"The Center for Advanced Mineral and Metallurgical Processing (CAMP) has recently obtained a Mineral Liberation Analyzer (MLA). CAMP has utilized the technology for several projects with excellent results. The MLA is able to both analyze size and quantify mineral phases. Therefore, the MLA is becoming the Sherlock Holmes of the mining and metallurgical industry. For this presentation, four projects have been evaluated and data was collected using the MLA. The first project involved tungsten mine. Previous mining practices have yielded poor tungsten results and recoveries. By using the MLA, tungsten mineral phases, along with possible contaminants, were verified and the results used to try to increase overall tungsten recoveries. The second project evaluated a molybdenite/chalcopyrite concentrate with surprising results. The third project is a silver project. Initial flotation scoping tests were performed by attempting to separate silver from gangue material. Because of the poor recovery results (less than 5%), MLA was used to determine possible scenarios for increasing silver recovery. Finally, the last project involves gold evaluation in tailings. For all projects, MLA application results will be presentedand discussed.INTRODUCTIONThe Center for Advanced Mineral and Metallurgical Processing (CAMP) has recently received a software add-on to a scanning electron microscope (SEM) located at Montana Tech. The Mineral Liberation Analyzer (MLA) technology was developed by Dr. Ying Gu of the JKTech Center of the University of Queensland. Since August 2006, CAMP has received and processed over 50 samples. These samples include a total mineralogy of tungsten ore samples, gold tailings, lead zinc tailings pile, molybdenite concentrates, copper concentrates, as well as others. During analysis of these received samples, the technology allows the samples to be quantified mineralogically with some surprising results.For analysis, the samples were initially sieved between 170 to 200 screen sized mesh. This ensures that received samples mineral size is fairly uniform. The samples are then placed into epoxy and allowed to harden. Next, the samples are polished and carbon coated for MLA analysis."

Jan 1, 2007

By John A. Herbst, Xiangjun Qiu

"Prediction of wear on a microscale level in mineral processing equipment turns out to be a challenging undertaking. This is particularly true for cases in which the objective is to use such predictions for wear parts design. The key to obtaining such predictions has turned out to be the use of physics based models along with phenomenological constitutive equations. In this paper, two components of the HFS tool set, one for particles (DEM) and one for slurry (MPF), are used for modeling. These tools are applied to the simulation of wear of SAG/AG shell lifters/plates and wear in slurry pumps. In each case wear predictions are validated with plant measurements.INTRODUCTIONHigh Fidelity Simulation (HFS) has emerged as an important tool set for mineral processing plant equipment design and optimization (Herbst and Potapov, 2003; Herbst and Nordell, 2002; Herbst and Lichter, 2006). This tool set consists of Discrete Element Modeling (DEM) of particle motion, Multi-Phase Flow (MPF) for liquid motion, discrete grain breakage (DGB) for particle fragmentation and discrete grain liberation (DGL) for mineral liberation (Campbell, Potapov and Tsuji, 1997; Ferzinger and Peric, 1997; Potapov and Campbell, 1996; Herbst and Potapov, 2005).Three sample snapshots of basic HFS illustrating the use of each of the various types of mineral processing equipment are shown below.Figure 1 shows a snapshot of a DEM simulation of ball charge motion in a commercial scale Vertimill. DEM simulation involves simultaneous solution of Newton’s Laws of Motion for 400,000 balls."

Jan 1, 2007

By Dayle Denton, Lloyd Buckingham, Kenneth G. Thomas, Jacques McMullen

"The dry grinding and leaching circuits of Barrick Gold’s new Roasting Facility at Goldstrike Mine in Nevada, USA incorporate well proven technologies in a unique combination. During the design of the plant, every effort was made to utilize the best available technologies from the perspective of capital, environment and operating costs.Crushing is a two stage process using gyratory and cone crusher. Ore is stockpiled and then reclaimed to two parallel dry grinding mills. The double rotator dry grinding mills include a drying chamber, coarse and fine compartments and utilize a gearless motor drive (GMD) or “wrap-around”. In-circuit product transfer is accomplished with air slides and bucket elevators. Finished product separation is performed by both static and dynamic classifiers with the final product captured in baghouses. Recycle of unfinished product utilizes cascade chutes.The final ground product reports to two 2000 ton roaster feed silos. The two-stage oxygen flu-solids roasters with their associated gas train are the subject of a separate paper.The cyanide leach circuit is a standard carbon in leach system with circular swept screens for interstage carbon retention. The loaded carbon is sent to the existing Goldstrike autoclave plant for stripping and regeneration. Tails, after cyanide destruction, are deposited in the existing tailings dam with tails from the autoclave facility.Throughout the circuit, Clean Plant Design criteria were used to assure environmental compliance, ambiental acceptability and ensure worker health and safety. The commissioning and operation of the double rotator grinding technology has been very successful at Barrick Goldstrike."

Jan 1, 2001

By H. Zhu, Y. Sato, O. Takeda, K. Nakano

Recycling of rare earth magnet wastes is essential to insure the stable supply of rare earth resources. For the development of a novel recycling process, the removal of rare earth oxide from an off-spec alloy magnet was investigated by melting the alloy magnet at 1503 K together with fluoride flux, LiF-50 mol% NdF3 and LiF-?25 mol% NdF3-25 mol% DyF3. After melting, the separation of magnet alloy from the fluoride flux was achieved, and neither suspension of alloy in the flux nor suspension of flux in the alloy was observed. Oxygen concentration in the alloy decreased from 5000 mass-ppm to 160 mass-ppm by utilizing 1.5 times of equivalent amount of flux needed to completely dissolve the oxide. The investigated process is suitable for mildly contaminated waste such as a used (end-of-life) magnet because of its simplicity, low energy consumption and small limitation on location for operation.

Jan 1, 2014

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

This paper discusses how elemental analysis of conveyed bulk flows in real time using PGNAA (Prompt Gamma Neutron Activation Analysis) technology has resulted in significant improvements in advancing plant control in mineral processing operations. Basis of operation of the PGNAA through belt, full stream, continuous, multi-elemental, real time analysis technology is explained. Capabilities and limitations in plant operating environments are discussed including comparison with other real time, online technologies through review of published information available for on-conveyor minerals applications. Case studies demonstrate benefits provided by this technology in two operating mines. An iron ore company had prior experience with the PGNAA analyser technology, implementing an early model in a minerals application in 2003 to develop confidence in its measurement performance and usefulness of the data. A number of analysers were subsequently included throughout the new plant design for extensive measurement and control of conveyed bulk flows, from conveying after mining through to rail load-out. A copper-gold company installed an analyser to address copper ore blending issues where an on-belt system was the only viable option for the degree of control required. Analyser suitability was evaluated through test work on site samples to determine customised multi-element precision guarantees for each application. Analyser results from normal operation are compared against laboratory analyses of multiple cross stream samples collected from conveyed flows to assess performance. Both projects discussed were able to realise benefits previously unattainable for plant quality control, surpassing capabilities of traditional technologies which were either unsuitable for measuring conveyed flows with adequate accuracy or in real time. Equipment payback within a few months was achieved for both sites. Through proven performance in these applications, the companies consider the technology an essential component in advanced plant control necessary in new process flow sheet designs, rather than an optimisation tool.

Jan 1, 2014

By D. A. Trotter, G. J. Goddard

"This paper describes a method of deciding on various design parameters for a sublevel caving layout. Layout design curves are obtained from the output of a computer optimization program. The program uses mathematical relationships derived from the theory of gravity flow of material to optimize the large number of interdependent design variables which are involved.IntroductionIn the design of an efficient sublevel caving mining system, a large number of interrelated variables need to be considered. Although many papers discuss individual variables, very little exists in the literature to show how these variables interact to achieve optimum results. This can lead to trial and error in sublevel caving design, which can prove costly, particularly because sublevel caving is a mining method which requires integration with sublevels above and below. With no pillars being left, experimental stopes cannot be isolated for study. Unfortunately, the complexity of layout design and the costs associated with trial and error have caused many planning engineers to choose more tried and tested mining methods.Sublevel caving works best to extract low-value ore surrounded by incompetent rock. All phases of the mining method can be highly mechanized, allowing low operating costs and high production rates. Good safety records are achieved, as workers are always in 'good' ground and the method is regular, making it comparable to an industrial process."

Jan 1, 1981

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 Walter Smith

Environmental Quality Committee ?EQC was created in 1995 to facilitate dialogue between industry and northern communities and help build the understanding of the industry in those communities. ?EQC is made up of representatives from 32 northern communities. ?Meet regularly with Cameco to discuss on going and new projects. ?Tour mine sites on a yearly basis.

Nov 1, 2011

By Sunil Koppalkar, Liming Huang

"Since late 1980s the research group led by late Professor Andre Robert Laplante at McGill University undertook fundamental studies and applied research of the Knelson Concentrator (KC) and developed a sustainable method to correctly estimate gravity recoverable gold (GRG). In the early time a concept of ‘free gold’ was used, it was defined as the gold that could be separated and recovered from gold ore by amalgamation. Due to health and safety hazards, its practical use had declined. Around 1994, a methodology using a 3-in Knelson Concentrator to measure gravity recoverable gold was established at McGill University. Through more than 10 years’ improvement and optimization, this technique had become a standard method to evaluate GRG for gold ores, gold plant streams and platinum group metals. Until 2006, about 200 GRG tests had been carried out at McGill University for the ores from all over the world. Recently, a modified version of GRG test (short test) with the advantages of reduced processing time and lower cost had been developed for the mundane needs of gold industry.INTRODUCTIONGold gravity recovery has evolved significantly over the past twenty-five years, mainly because of the advent of the Knelson Concentrator (Knelson 1988, 1990, 1992, Laplante 2000). Now, a series of Knelson Concentrators for different applications are manufactured and used in gold industry all over the world (Knelson Concentrators 2004).In 1980s the Knelson Concentrator gained acceptance from mining industry as an effective device for the recovery of gold from grinding circuit. Knelson Concentrator became the obvious choice because of its design features: a relatively long processing time without concentrate discharge (compared to some other centrifuges, such as Falcon Concentrator and Chinese Yunxi Centrifuge at that time), large throughput capacity, treating a wide size range of material, yielding a high grade concentrate with small mass that could easily be smelted. As more and more Knelson Concentrators were accepted in gold industry, mineral processing engineers faced with challenges: what are the separation mechanisms of the Knelson Concentrator? How much gold can be extracted for an ore if a Knelson Concentrator is installed? For answering these questions, a laboratory scale Knelson Concentrator was created."

Jan 1, 2007

By J. A. Relf

The construction of refineries and gas conservation plants in the general Edmonton area in the early 1950's made available large quantities of by-product liquified petroleum gases (LPG). These gases, together with discovery of increasing reserves of natural gas in the Edmonton area, provided Canadian Chemical Company with two of the necessities for petrochemical production, namely, available and reasonably priced raw materials and fuel. This paper outlines the development of the $83 million Edmonton plant from its origin, together with a brief description of the processes and some of the interesting features involved. Several economic aspects of the petrochemical industry are high-lighted including its importance to the local community and the province. The paper reviews the relationship between the oil and gas industry and petrochemical manufacturing and indicates some of the factors that may affect the future growth of the petro-chemical industry in Wes tern Canada.

Jan 1, 1962

By Brenda M. Dixon

A matrix analysis of the differences between the camps and communities associated with the Britannia Mine is used to develop an analytical tool. The tool is intended to assist the mining industry as it embraces the many facets of sustainable development. A case study is used to support the identification of key factors that may predict the sustainability of a new mine town. Sustainable communities, like Britannia Beach, are discussed in the context of three pillars of sustainability: value of mining products to society; creating wealth; and, environmental integrity. A sustainable mine town may be viewed as a socio-economic asset as well as an asset to the mining industry.

May 1, 2006

"The McArthur River uranium deposit is the single richest uranium ore body developed in the world to date. The ore body’s average grade is 15% U3O8. Proven reserves are in excess of 450 million pounds. The grinding circuit is located underground. The ground ore is pumped to a surface facility where the slurry is thickened and loaded into containers for shipping to the Key Lake mill 78 kilometers to the south.The paper will briefly describe the mining method employed. The underground ore handling and grinding circuit, and surface facilities including slurry load out, wastewater treatment and the freeze plant will be described in detail. The paper will emphasize radiation and safety procedures that are followed to minimize operator exposure to radiation risks.LOCATIONThe McArthur River mine is located 78 kilometres north of the Key Lake mill. It is located at latitude 57’ N in northern Saskatchewan, within the southern boundary of the Athabasca formation. The nearest town is Pinehouse, located 320 kilometres to the south. Access to the mine is by an all weather road and by a private airstrip.HISTORYThe McArthur River Operation is jointly owned by Cameco Corporation (69.805%) and Cogema Resources Inc. (30.195%). Exploration for uranium in the McArthur River area started in 1980 by the Saskatchewan Mining Development Corporation, a predecessor company of Cameco.In 1984, a 12-kilometre long basement conductor was identified at a depth exceeding 500 metres. Systematic exploration drilling of this conductor resulted in the discovery of the P2 North deposit. Subsequent surface drilling programs from 1989 to 1992 delineated a narrow ore zone over a strike length of 1700 meters at a depth of 500 to 600 metres. At this time, geological reserves for the deposit were estimated to be 2.4 million tonnes at a grade of 5.0% U3O8 for a uranium content of 260 million pounds U308"

Jan 1, 2001

By Trevor Yeomans, David Yaschyshyn

"Placer Dome (CLA) operates the 90-year-old Dome Mine, in South Porcupine, Ontario.The milling operation currently processes 5 million tons of ore per year, from both the underground and Open pit mining operations, producing 320 000 ounces. The milling process is conventional crushing and grinding, with gold recovery by gravity followed by leach/CIP.Cyanide tailings are impounded in a large (325 ha) tailings area where cyanide is allowed to degrade naturally. Effluent is discharged seasonally during the summer and early fall months to maintain site water balance. Pond water is reclaimed for sole use within the mill process.In 1995, an Effluent Treatment Plant (ETP) was constructed for the purpose of removing dissolved metals and suspended solids. In 1997, an INCO S02/Air cyanide destruction module was added.During this time period, the treated effluent often failed toxicity tests required by the Ontario MISA Regulation, even though effluent chemical parameters were below permit limits. Two studies identified ammonia as the toxicant to Rainbow Trout, and free copper as the toxicant to Daphnia magna.From a literature study, and contacts within the Ontario Mining Association, the use of chelation as a final end of pipe treatment step to render any remaining free copper and metal fractions biologically unavailable was considered. Lab and plant scale tests followed.During the 1999 ETP operating season, the addition of the chelant EDTA (ethylene-diamine-tetraacetic-acid) commenced. To date discharged effluent has passed all toxicity tests.The paper will review the effluent treatment history, current effluent treatment plant operation, and detail the use of EDTA for successful toxicity control.History of Tailings Deposition, and Effluent Treatment From 1910 to 1995Over it’s ninety years of operation, the Dome Mine milling circuit has changed from the original 1910 stamp-mill mercury plant, to today’s modem 14 000 ton per day automated gravity and Carbon in Pulp based plant.By the 19803, a modern mill was operating on mainly underground mined ore. The plant was operating at some 3 800 tons per day, using fairly conventional processing routes.The number 4 tailings dam was being used for tailing’s deposition.All effluent treatment was by natural degradation of cyanide. Discharge was from decanting type structures during the summer months only, maximizing the use of natural degradation no tailings effluent was recycled for Mill use."

Jan 1, 2001

By J. R. Gordon

I-Introduction The possibility of adapting low-temperature reduction methods to the treatment of iron ores has been suggested on numerous occasions. Papers published on the subject include, notably, Bulletin 270 of the United States Bureau of Mines on The Production of Sponge Iron, the Symposium of the American Electrochemical Society (1927) on The Gaseous Reduction of Ores and Other Metallic Compounds, and Les Procédés Actuels de Traitement Direct du Minerai de Fer, by A. Mayer (Revue de l'Industrie Minerale, Nov. 15th, 1932) (1). The present paper contains the results of an investigation of the reducibility of some Ontario ores. The concentration of these ores and of the products of reduction has also been investigated.

Jan 1, 1933

By P. Mundell, R. Torbin

"There are many physical and operational obstacles in pipelines that make the passage of inspection robots impossible including:•,Small radius bends•,Low operating pressure•,Plug valves•,Large changes in pipe size•,No permanent access to the pipeline.The inspection of unpiggable pipelines requires the marriage of a highly agile robotic platform with NDE sensor technology operating as an integrated system. Foster-Miller and GE/PII are developing a robot that is essentially a battery powered, train-like platform. Both front and rear tractors propel the train in either the downstream or upstream direction. Like a train, the platform includes additional ""cars"" to carry the required payloads. The cars are used for various purposes including the NDE sensor module(s), the power supply, and data acquisition/storage components. The robot is designed with a slender aspect ratio and the ability to change shape as required by the physical obstacle presenting itself. The MFL sensor module must also morph itself through the physical obstacles, and thus, will require some level of segmentation. The segmented MFL magnetizers and transformable sensor module represent a major advance in the science of sensor technology and pipeline inspection."

Jan 1, 2005