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By John Starkey

This paper examines 5 years of SAGDesign testing data with particular emphasis on the grinding test results from two recent projects, the Fortune Minerals Limited NICO project, and the Aurora Energy Resources Inc., Michelin deposits, located in the Northwest Territories and in Labrador respectively. The context is to compare these results with the SAGDesign database. The required SAG mill pinion energy for these two ores showed vast differences, even though both ores had similar average Bond Ball Mill Work Index values - about 13 kWh/t each for the two deposits respectively. Bond Rod Mill Work Index values for NICO ranged up to 19.7 kWh/t for the hardest ore, confirming the harder nature of the coarse material. SAG mill pinion energy to grind the NICO cobalt-gold-bismuth-copper ore from F80 152 mm to T80 1.7mm varied from 16 to 35 kWh/t, while for Michelin uranium ore, it varied from 2 to 9 kWh/t. NICO ore is harder than any other material encountered to date using SAGDesign testing. SAG pinion energy is more than double the ball mill pinion energy using a transfer size T80 of 1.7mm and a final grind P80 of 74 microns. For NICO, the ore is ?off the charts? for simulation design techniques because there is no comparable operating SAG mill treating ore that is this macro-competent. For Aurora, the relationship between SAG and ball mill pinion energy is reversed in that the SAG mill requires less than half of the ball mill pinion energy using a transfer size T80 of 1.7mm and a final grind P80 of 90?. Because these discoveries are so important for grinding mill design, their impact will be dealt with in future papers, at the August METSOC Conference in Sudbury, and at the September SME Workshop in Tucson. It has now been concluded that the ratio of SAG pinion energy to Bond Ball Mill Work Index, is valuable data to use in designing a SAG/ball mill grinding circuit, to help choose the power split needed.

May 1, 2009

By C. W. Hancher, B. D. Patton, W. W. Pitt

"There are a number of nitrate-containing wastewater sources, as concentrated as 30 wt % NO3 and as large as 2000 m3/day, in the nuclear fuel cycle. The biological reduction of nitrate in waste water to gaseous nitrogen, accompanied by the oxidation of a nutrient carbon source to gaseous carbon dioxide, is an ecologically sound and cost-effective method of nitrate waste disposal. These nitrate-containing wastewater sources can be successfully biologically denitrified to meet discharge standards in the range of 10 to 20 g N(NO3-)/m3 by the use of a fluidized bed bioreactor. The denitrification bacteria are a mixed culture derived from garden soil; the major strain is Pseudomonas. In the fluidized-bed bioreactor, the bacteria are allowed to attach to 0.25- to 0.50-mm-diam. coal fluidization particles, which are then fluidized by the upward flow of influent wastewater. Maintaining the bacteria-to-coal weight ratio at approximately 1:10 results in a bioreactor bacteria loading of greater than 20,000 g/m3,This paper describes the results of a bio denitrification R&D program based on the use of fluidized bioreactors capable of operating at nitrate levels of up to 7000 g/m3 and achieving denitrification rates as high as 80 g N(N03-) per day per litre of empty bioreactor volume. IntroductionThe discharge of wastewater containing nitrate at concentrations greater than stipulated by the Environmental Protection Agency (EPA) creates an environmental hazard and constitutes a civil and/ or criminal legal liability.(I.2) At present, we have three options: (1) recycle and reuse of nitrate streams the total economic and technical balance should be Closely examined; (2) use of an alternative acid, which may pose an entirely different set of problems ; or (3) disposal of nonreusable nitrate sources by an environmentally acceptable procedure."

Jan 1, 1980

By V. T. Panayotov, M. I. Panayotova

Wastewater from mining and mineral processing activities is often polluted by anion forming metals, such as molybdenum and chromium. Low cost materials, including zeolites, are studied for removing heavy metals from wastewater. It is widely accepted that natural zeolites are not effective in removing metals in anionic form. The paper presents study on use of metal modified natural clinoptilolite to remove Mo (VI) and Cr (VI) ions from model soft wastewater. Modification with Pb, Fe(III), Zn and Ba increases clinoptilolite uptake capacity with respect to Mo(VI) at low pH values of the water subjected to treatment, the efficiency decreasing in the order Pb > Fe(III) > Zn > Ba. Only lead-modified clinoptilolite shows high uptake of Mo(VI) in acidic, neutral and slightly alkaline conditions. Modification with Pb, Ba and Fe(III) increases zeolite uptake capacity with respect to Cr(VI) from neutral water. The effectiveness of Ba-modified zeolite decreases in slightly acidic water. Over 90 % uptake of initially available Cr(VI) is achieved by lead-modified clinoptilolite both under neutral and slightly acidic conditions. Increasing the initial pollutant concentrations increases the removed amount both of Cr(VI) and Mo(VI) for Pb-modified clinoptilolite. The findings could be a basis for using the natural clinoptilolite to remove in consecutive steps: firstly Pb(II) and/or Fe(III) ions and then loaded zeolite to be used for Mo (VI) and/or Cr(VI) removal. The kinetics of Mo(VI) uptake by CL-Ba, CL-Fe(III), CL-Pb, and CL-Zn is best described by the pseudo-first order kinetic equation. The kinetics of Cr(VI) removal by CL-Ba, CL-Fe (II), CL-Fe (III) and CL-Zn is best described by the pseudo-first order kinetic equation. Kinetics of Cr(VI) removal by CL-Pb obeys the equation for the first order irreversible reactions. Finding way to remove anions-pollutants from the mineral processing wastewater will render this industry more environmentally friendly and socially acceptable.

Jan 1, 2016

By Raymond Dallaire

The Humphrey's spiral is a static gravity separation device which cannot be adjusted to match short-term variations that occur in the feed. Any disturbance in the feed grade, per cent solids or flow rate affects substantially the recovery and grade of concentrate. Such variations must be minimized in order to maintain the desired rate of production and quality of the product for which the installation has been designed. A study has been performed in which the foregoing assertions were quantified. The feed grade, per cent solids, flow rate and particle size were varied independently. Ore from Carol Lake, Nfld., was used throughout the experiments. This consisted of specular hematite and magnetite in a silica gangue.

Jan 1, 1978

By Peter Harben

"This paper discusses the benefits of industrial minerals, their sources of supply, price and marketing trends, and their increasing use as substitute materials and ""strategic"" minerals. IntroductionKaolin finds have yet to spark the kind of frenzy associated with the 1849 California gold rush; no dolomite deposit has ever gained the notoriety of the Comstock Lode; and few industrial minerals are counted among the currently fashionable list of "" strategic mineral s"". Nevertheless, the glamorous zhine associated with metals may be somewhat superficial; further digging provides perhaps the real foundation of modern society - industrial minerals.They are often tagged as common, everyday materials that are simply dug out of the ground, crushed and hauled to a local point of consumption. Although this description is accurate in the case of road aggregates, sand and gravel, and the like, there are many exceptions to this rule. The term industrial minerals is rather nebulous, covering as it does the mundane and esoteric, the chemically active and the refractory, the $2 and the $10m-a-ton product. All of these minerals influence every facet of modern life from fertilizers to fire retardants, ceramics to cars, construction to clothes, and toothpaste to tennis courts. Their usefulness is well illustrated by the variety of industries they serve; the main ones are listed in Table 1. It is now time to dismiss the notion of non-metallics as the ""third world"" of natural resources business after the metallic and energy products by dispelling some of the myths regarding abundance, variety and value of the group's sixty-plus products."

Jan 1, 1982

By Enrique Rubio

Several mining operations are currently evaluating the feasibility of changing their mining method to Block Caving. There will also be several deep low-grade ore bodies that will face the need to go underground in following their ore to depth. There are two main reasons why Block Caving is attractive: firstly, it offers the lowest operating costs amongst all the mining methods; and secondly, it is truly a massive mining method, offering the highest potential production capacity. Despite its longstanding popularity, there are still significant components of the method that are not clearly understood. Also, the lack of availability of key geomechanic information still presents a major obstacle to developing mine planning and production scheduling. There are several key issues in block caving that can make it feasible such as cavability, fragmentation, stresses will condition the way that a block caves and the way that material is drawn from the draw points. Consequently Block Cave mining method is a good example where the ore body has to be related to design and mine planning. The concepts of dilution, draw control as well as sequence definition are reviewed in this paper to illustrate the idea of integration. There have been some examples of mines where some of the components of mine planning have not been integrated causing a disaster in terms of economics or safety. Different layouts configurations might give a different result in the planning of the mine

May 1, 2002

By J. Ouellet

"ABSTRACTA brief background on in-situ testing of mine backfill, as well as pressuremeter testing is briefly described, and results from an in-situ testing on paste backfill are presented. A series of self-boring pressuremeter tests were done from the top of a backfilled stope in an underground mine. The tests were conducted along a 20-metre vertical line in the centre of the stope. Some 14 tests were performed along this depth. The instrument used was a Camkometer built by Cam Insitu, Cambridge. The instrument proved to be efficient and reliable for underground testing in a cemented paste backfill. The testing program was conducted within the planned schedule with a high success rate. The test done in this study permitted the measurement of paste backfill strength, stiffness and in-situ horizontal stress within the backfill. RésuméUn bref historique des essais in situ dans le remblai minier est présenté. L’essai pressiométrique est décrit succinctement et des résultats d’une campagne d’essai dans un remblai en pâte sont présentés. Un programme d’essais au pressiomètre auto-foreur a été réalisé à partir du sommet d’un chantier remblayé sous terre. Les essais ont été réalisés le long d’un ligne vertical d’environ 20 mètres pour un total de 14 mesures. Le Camkometer de la firme Cam Insitu de Cambridge a été utilisé. Cet instrument s’est avéré efficace et fiable pour tester le remblai en pâte cimenté sous terre. Le programme d’essai s’est déroulé à l’intérieur de l’échéancier prévu avec un taux de réussite élevé. Ces essais ont permis de déterminer la résistance, la rigidité de ce remblai ainsi que les pressions in-situ prévalant dans le remblai."

Jan 1, 2000

By J. Béland, C. Giguère

"The auriferous mineralization at the Sigma-2 gold mine occurs in quartz-carbonate-tourmaline veins emplaced in a fractured granaphyre layer in the upper part of a differentiated gabbro-diorite sill. Kinematic indicators show that fracture planes were active as strike slip, dip-slip (reverse) and tensional faults.Measurements of attitudes of fractures and movement vectors indicate eight different sets that can be grouped into three systems: (I) an east-west oriented system includes a subvertical set and two other sets dipping north and south respectively; (2) a subhorizontal system of two conjugate sets bisected by a third tensional set; and (3)a system of sub vertical conjugate northeast and north-northwest trending sets.Kinematic analysis indicates that the subvertical set of the east west system was subjected to dextral strike-slip movement activated by a northwest-southeast compressive stress whereas the bulk deformation resulting from the remaining and subsequent seven sets can be explained by a protracted subhorizontal north-south compressive stress.The valuable gold mineralization is found principally in the fracture-filling veins of the subhorizontal system and subordinately in the other sets; among these other sets, the NE trending subvertical one is slightly more favourable.The over-all tectonic picture is that of an early mild dextral strike slip faulting in a ductile-brittle medium followed by a general flattening involving, first, a vertical and, later, a lateral extension by fracturing in a medium that had become brittle.The structural features are such that the differentiated sill could not be the source of the auriferous hydrothermal solutions."

Jan 1, 1990

By G. W. Poling, E. M. Coelho

"Sedimentary phosphate ores make up approximately 87% of the world's known reserves and are generally more difficult to beneficiate than igneous ores. In almost all cases, desliming prior to flotation represents the major source of losses. Laboratory studies of selective desliming of sedimentary ores are presented. Some fundamental studies with pure mineral systems are also discussed. Selective desliming, especially using selective flocculation, gave the best performance. Possible industrial applications of this selective flocculation-flotation procedure are discussed.IntroductionPhosphate ores are a major source of raw materials used in inorganic fertilizers (which supply nitrogen, phosphorus and potassium). Approximately 96% of the total world production of phosphate is utilized in the fertilizer industry. Reserves and production data are available in the literature. Today deposits with grades as low as 4% P2O5 are exploited in a few cases. However, in some northern African deposits, ore grades are still as high as 33 - 35% P2O5. Hout pointed out in 1982 that approximately 200 million tonnes of phosphate ore were upgraded by flotation only.Although there is a large number of phosphate minerals (over 300, only those in the apatite series are important ore minerals in phosphate ores. The most common member in this series is fluorapatite – Ca5(PO4)3F. However, in sedimentary phosphate rocks, many different substituents occur in the apatite lattice. Carbonate-fluorapatite (or francolite) is one of the most common names used to describe sedimentary apatites. It can be represented by the empirical formula:"

Jan 1, 1986

By T. C. Holmes

"Dome mine, in the Porcupine mining camp of northern Ontario, is one of the important gold mines of Canada, its production of gold from the commencement in 1910 to the end of 1946 having a value of $149,000,000.GENERAL GEOLOGYThe oldest rocks in the mine are greenstones of Keewatin age(l). Those to the south are known as the southern greenstones, but little is known of their structure. Those in the northwest part of Fig. 1 and the north part of Fig. 2 are known as the northern greenstones or greenstone 'nose'. They face north, dip steeply north, and end to the east against an unconformity which pitches northeast about 20°. The volcanics are overlain unconformably by Timiskaming .conglomerate and slate. All these rocks are cut by porphyry. Closely associated with the porphyry is a group of rocks that have suffered extreme alteration. Diabase dykes intrude all the other rocks and the ore. The principal massive rocks in the mine are two adjacent flows known asthe andesite (south) and dacite (Fig. 1). They are composed chiefly ofmassive, medium-grained lava. Pillows, flow lines, and other typically volcanicfeatures are found along the tops of both flows and at other places in theandesite. These parts nearly everywhere show a slight schistosity panllelwith the flows except in the orebodies, where they are massive."

Jan 1, 1954

By D. M. Hausen

"Refractoriness in Carlin-type gold ores results mostly from fine locking of gold in pyrite, locking in various gangue phases, notably quartz, and a ""preg robbing"" condition attributed to organic carbon. All three conditions may occur in any given deposit, including Newmont &apos;s Carlin and Gold Quarry deposits in Nevada, where types of ref ractoriness occur locally in minor amounts.Measurements of specific gravity, water absorption and screen size distributions of gold in alteration rock types from Gold Quarry show transitional changes from siliceous cherts through decreasingly silicified and increasingly argillized siltstones.Low permeability of siliceous ores contributes to ""size dependent"" refractoriness in cyanidation test work. Colligative physical and chemical measurements demonstrate that silicified cherty ores are difficult to grind, poorly permeable, and less amenable to cyanidation. Refractoriness in pad or column leaching of coarsely crushed siliceous siltstones and cherts is shown to correlate with interrelated measurable mineralogic and physical parameters.IntroductionMetallurgical treatment of variably amenable and refractory types of gold ore may be guided by both analytical and mineralogic data on the interlocking of gold (microscopic an d sub- microscopic) in assorted gangue/sulphide phases. Most oxidized ores from the Carlin gold mine, north of Carlin, Nevada, are amenable to direct cyanidation. The permeability of most oxidized ores from Carlin coupled with the fine size of the gold < 1.5 um) yields rapid extractions and high recovery without fine grinding.Small portions of the Carlin ore body, and also the nearby Maggie Creek and Gold Quarry orebodies, are less amenable to cyanidation, and are classified as refractory. Refractory conditions may be attributed mostly to the association or interlocking of gold with pyrite and /or microcrystalline quartz or chert, and also by the adsorption of leached gold by deleterious forms of carbon, termed ""preg-robbing"" carbon. Each of these conditions are described and defined, with emphasis on a form of silica-locking, which has been referred to as "" size dependent"" refractoriness."

Jan 1, 1985

By L. Chunpongtong

ABSTRACT The mining limit in oil sands is regulated by the ratio of total mining volume (ore, interburden, and overburden) one has to mine per volume of bitumen in place (TV/BIP). This paper presents a mathematical solution for creating the most economical pit outline where the TV/BIP ratio upper limit is 12, by combining mining economic theory and the Lerchs-Grossmann (LG) algorithm.

Jan 1, 2014

By L. Chunpongtong

The mining limit in oil sands is regulated by the ratio of total mining volume (ore, interburden, and overburden) one has to mine per volume of bitumen in place (TV/BIP). This paper presents a mathematical solution for creating the most economical pit outline where the TV/BIP ratio upper limit is 12, by combining mining economic theory and the Lerchs-Grossmann (LG) algorithm.

Jan 1, 2014

By C. Turek, R. Henderson

Mine planning is the foundation of value for a mining company. Good mine planning requires solid understanding of the ore body, rigorous standards and processes, robust and useful information technology and skilled people. Life of mine planning is key to identifying strategic direction for any mine and short range mine planning is key to delivering forecast and budget expectations. Mine planning at Kinross has been identified as a critical success factor and initiatives are being prepared to improve the quality of our plans and to build bench strength in our teams. The Kinross Way for Mine Planning (KWMP) has been developed and implemented to establish the standards to ensure a strong business foundation. This paper briefly describes the process used to develop the KWMP and presents a selection of mine planning best practice initiatives at Kinross mines.

Jan 1, 2011

By Richard P. Taylor, Rod Henham

Abstract - Newly discovered pegmatites distributed throughout the sub-surface environs of the Musselwhite Archean gold deposit occur as narrow dikes that intrude most of the major lithological units. The mineralogy and textures of the pegmatite dikes are characteristic of granitic pegmatites of the "Rare-Element Class"; more specifically, they closely resemble varieties of the "Complex-type" granitic pegmatites that are commonly associated with zones of tantalum mineralization. The essential minerals in the dikes comprise albite, quartz, and K-feldspar, together with lesser amounts of mica (including lepidolite), spessartine, tourmaline, and locally, spodumene. Fine-grained (30 µm to 300 µm), tantalum-bearing minerals occur in the quartzo-feldspathic matrix of the dikes as disseminations, in interstices, and in small vugs. The nature of the tantalum-bearing mineral assemblage present in individual pegmatite dikes varies from a simple mineral assemblage composed of ferrocolumbite (with around 39 wt% Ta2O5) in the most northerly dike, to more complex assemblages comprised of manganotantalite (with up to 75 wt% Ta2O5), ferrotapiolite (with up to 79 wt% Ta2O5), and microlite (with up to 76 wt% Ta2O5) that are present in dikes located several kilometers to the south and southwest. The compositional characteristics and textural relationships of the tantalum-bearing minerals in the dikes provide evidence of igneous fractionation trends that are typical of rare-element granitic pegmatites. Such trends suggest that the newly discovered pegmatites represent part of a more extensive group of cogenetic, tantalum-mineralized dikes.

Jan 1, 2001

By Allan J. Guse

The primary limiting factor for hoisting capacity from great depths is the self-weight of the typical steel wire ropes used for mine hoisting. Steel wire ropes possess properties making them very suitable for mine hoisting including high strength and durability, but have the negative characteristic of being relatively heavy in comparison with their strength. Also, as hoisting depths increase, the service life of steel wire ropes decreases due to the higher stresses and physical effects on the ropes. The significantly higher strength-to-weight ratio of synthetic ropes compared with steel ropes offers the primary advantage of hoisting a larger payload with a similar size rope and hoisting plant. The beneficial properties of synthetic ropes could be used to improve the overall economics of deep underground mining both for new deep shaft projects and for existing mining operations expanding to deeper orebodies. A research and development program has been initiated to evaluate the suitability of a fully synthetic rope for the mine hoisting application, including rope discard methodology and NDT testing. The three phases/projects are: 1) proof of concept with focus on coilability under load (successfully completed in 2012); 2) high speed and load durability optimization & NDT Development; and 3) in-situ mine trial.

May 1, 2013

By S. Dominguez, E. Gebrehiwot, S. Richardson, S. Sandoval

Copper electrowinning/electrorefining (EW/ER) is powered by direct current (DC) rectifiers that typically generate 30,000 to 70,000 amps and a bus-bus voltage of 200 to 500 volts DC. Tankhouses are designed so that DC current flows through “cell lines” which contain individual EW/ER cells electrically connected in series. Electrolyte composed of copper sulfate and sulfuric acid in water forms the “liquid conductor” that connects the metallic conductors in this circuit. In this setting, stray current is a DC current that strays from and therefore bypasses the tankhouse circuit by finding a path to ground, often through the electrolyte in pipelines that feed into and discharge from the cells, or through dried electrolyte (i.e. sulfate), which is also electrically conductive. Tankhouse workers can be exposed to shock hazards if they become part of a stray current path to ground. This presentation details examples of stray current shock hazards in electrolytic tankhouses and provides voltage and amperage measurements associated with stray current in these examples. A review of critical safety controls in EW/ER tankhouses that will mitigate the risk of employee shock from stray current is also provided. INTRODUCTION Electrolytic tankhouses are designed to deliver relatively large amperages of DC current to a series of electrolytic cells in which copper is plated out of solution using the classic anode-cathode pair geometry within each cell. Electrolyte is the “liquid conductor” that transfers current in between the metallic conductors of the cell. The metallic conductors include inter-cell copper bus bars and the anodes and cathodes themselves. It is sometimes forgotten that electrolyte as a conductor is capable of delivering DC current outside the designed circuit of a tankhouse. Stray current is a DC current that strays from the tankhouse electrical circuit by finding a path to follow other than the designed path. Safety becomes a concern when there is a risk of an employee becoming part of an accidental stray current path, thereby suffering an electrical shock. In 2016, Freeport-McMoRan (FMI) suffered a fatality at one of its copper electrowinning tankhouses. The forensic analysis concluded that stray current from the tankhouse rectifier contributed to the fatality. An employee accidentally fell into contact with a metal flange at the end of an HDPE pipe that was collecting cell overflow electrolyte from the tankhouse. DC current passed through the employee to ground, creating a shock that was judged to contribute to his death. The situation was exasperated because the employee was unconscious, and therefore was exposed to the stray current for several minutes before being found. In addition, the employee’s clothing was saturated with liquid, and the employee was found kneeling in puddled liquid on the ground. FMI immediately began an investigation into the root cause of the stray current that was measured at the scene. Sufficient electrolyte had accumulated in the HDPE pipe such that a continuous path was formed between it and electrolyte that was continuously overflowing from energized electrowinning cells. The metal flange on the pipe was the metallic conductor that carried the current to the employee from the electrolyte inside the pipe. Current then flowed through the employee to ground. Because of this incident, FMI undertook an extensive review of the hazards of stray current in EW/ER. FMI’s tankhouse workforce received a Tankhouse Electrical Safety training course developed in- house to insure worker understanding of stray current hazards. Tankhouse design changes were implemented to better insulate workers from stray current. Personal protective equipment (PPE) standards were also reviewed and changes made.

Jan 1, 2019

By J-F. Magnan, M-A. Thibault, R. Boulianne, C. Gauthier, J-P. Gagné, G. Dufour

During the production of aluminium in smelters, the anodes used in electrolysis cells have to be replaced frequently. Anode butts are usually placed on anode trays for transportation and cooling, a practice during which Hydrogen Fluoride (HF) is emitted in large quantities. Covers developed in 2000 by Alcoa Deschambault to fit on the anodes trays were implemented, resulting in significant reductions of HF emissions. However, the covers are expensive to maintain and use short-life consumable parts. In January 2004, STAS and Alcoa decided to develop a more efficient design of cover, with lower maintenance costs and no need for consumable materials (like soft cushions). This paper presents a summary of the work performed to develop the new design as well as a summary of the test results.

Jan 1, 2006

By Roger D. Plouffe

In today&apos;s mining industry, it is possible to retrieve, from small-diameter holes, geophysical data for qualitative interpretation in exploration and quantitative interpretation in the development of orebodies. The primary objectives in the exploration stage are to identify where, within a hole, economic minerals are, and to help in lithological interpretations. Other aspects, which are more quantitative, are the interpretation of downhole logs for parameters which can be used in surface geophysical methods (i.e. density for gravity surveys, acoustic velocities for seismic surveys, and magnetic susceptibility for airborne and ground magnetic surveys). Recent advances in equipment design, portability and durability have made downhole logging in exploration more inexpensive and reliable. This new equipment is being used to generate very precise quantitative results. This is especially true on uranium development projects. The interpretation of gamma logs for eUJOS values has finally become precise enough that they have begun to replace chemical values in reserve calculations. Another part of development data is density and equilibrium information, which, with today&apos;s technology, is being derived from downhole probing. In the years to come, the trends for many metals are toward neutron activation techniques, or "in-situ assaying", and the use of multiple logs for better lithological and physical rock property determinations.

Jan 1, 1981

By A. Belleau, F. Lavoie

"Quebec Iron Ore Limited (QIO), a subsidiary of Champion Iron Limited (Champion), secured assets in early 2016 from the previous Bloom Lake operations in the heart of the Labrador Trough region of Northern Quebec, Canada. A plan was developed to bring the Bloom Lake facility back in operation once the iron ore market conditions improved. The project restart involved several aggressive moves to change operational effectiveness, one of which was the utilization of the existing Phase 1 Plant with an upgraded process flowsheet and equipment. The production target was 7.4 million tonnes per annum of 66% iron ore concentrate with an approximate 10% increase in iron ore recovery. The Phase 1 upgraded flowsheet was initially based on review of historical Phase 1 data and pilot testing data undertaken during the original Phase 1 operation and was finalized once additional metallurgical test work and process modeling was carried out by Mineral Technologies in late 2016. The final upgraded flowsheet is comprised of rougher spirals, rougher middling scavenging spirals, and an up-current classifier (UCC) with overflow scavenging spiral stage. A portion of the gravity circuit tailings treated by a series of wet high intensity magnetic separators (WHIMS) to boost overall iron recovery. This paper will describe the efforts taken to test and design the Bloom Lake Phase 1 upgraded flowsheet and report on the plant performance since commissioning in first quarter of 2018.SITE HISTORY The Bloom Lake iron mine property is located approximately 13 km north of Fermont, Quebec, and 10 km north of the Mont Wright iron ore mining complex, property of ArcelorMittal Mines Canada. The Bloom Lake mine facilities include a 32 km railway to efficiently transport the high-quality iron concentrate to a loading port located in Sept-Iles, Quebec. The Bloom Lake property was first explored in 1951 and went through multiple minor exploration campaigns by different companies up until 1998. A major exploration program was conducted by Quebec Cartier Mining (QCM) in 1998. This program included line cutting, surveying, diamond drilling, geological mapping, mini-bulk sampling, bench-scale preliminary metallurgical test work and preparation of a “mineral resource” estimate."

Jan 1, 2019