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By W. M. G. Heeley

In the province of Alberta the coal measures dip at so many different angles, between the horizontal and the vertical, that many different systems of haulage are in use. I will, however, only touch briefly upon the general -systems in use, and devote the major portion of this paper to a discussion of endless-rope haulage and its adaptibility to various conditions in coal mines; dealing in particular with the endless-rope haulage that was installed at Brule during the month of August 1923. In coal seams that are approximately level, and newly opened, hand-putting or tramming from the face is the cheapest, but when the mine is further developed tramming is out of the question, and the use of ponies is the next consideration. The time arrives, however, when mining reaches a point where the economical haulage of coal by horses cannot be done profitably, and then some system of mechanical haulage must be installed. The installation of any system should be carefully considered before any particular type of haulage is adopted, because a great deal depends upon the grade or dip of the seam. Motor haulage is impossible to operate profitably on a grade of over 6 per cent and, while it is possible to use ponies, on short runs, up to 9 per cent, some other means of main and secondary haulage must be installed when a 9 per cent grade, is exceeded. I will, therefore, deal first with secondary haulage, because even though a main haulage is established, secondary haulage can be used to feed the main haulage.

Jan 1, 1925

By A. F. Abd El-Rehim

The behavior of both transient and steady state creep of Al-4.5 wt% Cu and Al-4.5 wt% Cu-0.1 wt% In alloys was investigated using a constant stress where torsional oscillations of different frequencies and shear strain amplitudes were operated at various working temperatures. An augment in both transient and steady state creep rates was observed by increasing both frequency and shear strain amplitude of the applied oscillations. The mean values of the activation energy of both alloys for both creep stages were found to be equal to that quoted for dislocation intersection mechanism.

Jan 1, 2006

By R. E. Dye

Introduction Research concerning all phases of hoisting practice, but more particularly the causes and prevention of hoisting rope deterioration and the improvement of safety dogs 158 for shaft conveyances, has been carried on intensively for the past three years in the Province of Ontario. Prior to the hoisting accident at the Paymaster mine on February 2nd, 1945, there had been no fatalities in the Province due to a hoisting rope failure. It was probably on this account that little original research on hoisting problems had been undertaken here and that the mining industry had been content to look to British, South African, and United States investigators for new developments in this field. Except for the Paymaster accident this might still be the case since, in any industry, it is apparently necessary for a serious accident to occur before any extensive programme of preventive research is launched. When this accident occurred, the Government of Ontario, with the close co-operation of the Paymaster officials and the mining industry as a whole, took immediate steps to determine the cause. A five-man, non-industry committee, selected from the Faculty of the University of Toronto with Dean C. R. Young as Chairman, was appointed by the Government, and a three-man Committee consisting of R. D. Parker, General Superintendent of the International Nickel Company of Canada, Limited, R. L. Healy, General Manager of Wright Hargreaves Mines, Limited, and R. E. Dye, General Manager of Dome Mines, Limited, with the latter acting as Chairman, was appointed by the Ontario Mining Association.

Jan 1, 1948

By J. H. Fulton

Summary Considerable test work has been done with the detachable type of carbide bit. In general, these bits improved drilling operations, but at a bit cost .greater than was compensated for by the reduction in man-hours of labour. Too few bits continued in service for the possible drilling life of the carbide inserts, and technical improvements or lowered first cost, preferably .both, are indicated ?in order that the bits can be generally acceptable as an economical drilling tool. In ?preliminary test work, the drill rods .with ?one insert of the chisel-bit type appear to be more trouble-free, to have a longer life, and to give a somewhat lower bit cost per foot drilled, than other types. INTRODUCTION The object of this paper is to outline briefly the 'methods used and the results obtained in test work with tungsten carbide bits used in combination with the smaller bore, lighter weight rock drills. As various articles have appeared in the past few years giving the historical background ?and early development of carbide ?bits, this information will not be repeated. Table I lists the equipment used in the test work. The stopers weigh about 95 pounds and the jackhammers with airleg from 97 to 110pounds. The smaller rock drills are stated to deliver about 2,200 blows per minute at 1 to 30 rotation and to require 85 to 95 cubic feet of air at around 100 pounds pressure.

Jan 1, 1950

By A. Ducastel, S. Connemann, A. Stark, F. Bouillot, C. Fricke-Begemann, LSA, H. Knapp, L. Horckmans

"Refractory materials are essential for all high-temperature applications in industry. Depending on the position in the furnace and specific process requirements, refractories are produced from several raw materials, such as dolomite, magnesite, bauxite, graphite or chromite. Most of these raw materials are not rare but strict quality requirements limit the producers of refractories to only a few deposits in the world. Thus, raw material supply is a critical factor for the production of refractories and accounts for 40-50 % of the total costs of refractories.A possible way to lower dependency on raw material supply is recycling of spent refractories. Main challenge in recycling is the separation of different brick types from each other and the removal of impurities, such as steel or slag. The European FP7 project REFRASORT aims to apply sensor-based sorting for separation of spent refractories. Sensor-based sorting is known from food industry, recycling and mineral processing and has proven its reliability. Nevertheless, some adjustments are necessary compared to applications in mineral processing because of other sensor-types and a higher number of products in one sorting step. This paper presents the results of feasibility tests for sensor-based sorting of refractories with near infrared spectroscopy and laser-induced breakdown spectroscopy (LIBS). Both sensors showed the potential to identify different brick types but the most promising results were obtained using LIBS technology. INTRODUCTIONRefractories are solid, ceramic products, which can sustain temperatures of more than 1500°C, without losing their stability or shape. Bricks of refractories have to withstand corrosion in contact with liquid steel or slag. Various high temperature applications, such as the production of glass, steel, copper or cement, require high quality refractories. The quality requirements of refractory bricks are strict, because small impurities can lower the thermal strength significantly."

Jan 1, 2016

By A. Gauthier, J .. E. Muir, M. Cormier

Falconbridge's Lac Shortt gold deposit is located in Gand Township, some 25 km north-east of Desmaraisville, The deposit was outlined in i980 by a drilling program me conducted by Falconbridge Ltd. in a joint venture with Corporation Falconbridge Copper after three years of systematic exploration by Falconbridge Ltd. in the Desmaraisville area. The gold bearing structure had previously been drilled by three other exploration companies. As based on an underground development programme conducted by Corporation Falconbridge Copper, the "in-si tu" mineral inventory to a depth of 500 metres at a cut-off grade of 3.0 g/t is estimated at 1 937 605 tonnes at a grade of 6.4 g/t (uncut) and 6.0 g/t (cut). Regionally, the stratigraphy consists of thick sequences of volcanic and volcanosedimentary rocks intruded by numerous and voluminous mafic (gabbro), felsic (granodiorite, syenite) and anorthositic intrusions. Structurally, at least two fold sets and one major fault system (E-NE) are present. Minor fault systems oriented E-NE and N-NW also occur. Mine stratigraphy can be divided into 1) - the hangingwall; 2) - ore zone; 3) - footwall. Hanging wall rocks include: a) green lapilli and blocky tuff b) transition zone c) green mica crystal tuff and d) red dolomitic tuff. Ore zone rocks include: a) bleached mafic tuff b) barren carbonates, c) pyritic dolomitic tuff (?) and d) brick-red syenite. Footwall rocks include: a) magnetic lava (so-called diorite), b) mafic lapilli and blocky tuff and c) alkali basalt, Native gold is the only gold mineral so far identified and it occurs both as free grains in gangue and as micro-inclusions in pyrite. Two geochemical groups were identified in the main rock units: 1) Alkali-rich rocks cons is ting of the ore zone and foot wall rocks and 2) Subalkaline group consisting of the hanging wall rocks. Ore analysis also shows Ba, Sr, W, Zr, REE and F enrichment in the ore zone. Footwall rocks are enriched in Na20. Present geological and geochemical data do not permit a clear interpretation of the formation for the Lac Shortt gold deposit but suggest it is a volcanic-hosted stratabound type. The bulk of the mineralization is associated with an exhalative phase following alkalic, carbonic, hydrothermal activity and part of the mineralization is associated with a late intrusive phase.

Jan 1, 1984

By Peter Hood

Data on world-wide geophysical activity in mining exploration programs are collected annually by the Society of Exploration Geophysicists' Geo-physical Activity Committee as part of a continuing service to the industry. The data are obtained by sending out questionnaires to all organizations which are known to be carrying out mining geophysical work; the organizations canvassed include mining companies, contractors, government departments and universities. The questionnaire is divided into three sections; namely, ground methods, airborne methods and research. The data compiled from the questionnaires show that world-wide utilization of mining geophysical methods reached a new high in 1967 with total expenditures of (U .S.) $32,323,240. This was divided as follows: ground methods, $18,106,785; airborne methods, $10,-123,405; and research, $4,093,050. For the ground methods, most money was spent on the induced polarization technique ($5,681,780); electromagne-tic methods were second in reported expenditures ($2,010,900). The total reported geophysical line mileage flown was 1,275,072 line miles, with aeromagnetic surveying being the most popular airborne method. The total amount spent on aeromagnetic surveys was $5,832,564 for 895,420 line miles. This gives an average cost of (U.S.)$6.50 per line mile.

Jan 1, 1968

By H. Arima

The Akita Zinc Company is the only refinery which produces hematite from the iron content in the zinc leach residue. The Akita Hematite Process consists of five stages, which are SO2 pressure leaching, the first neutralization stage, the de-arsenic process, the second neutralization stage and pressure hematite precipitation. In order to strengthen its cost competitiveness and stabilize its operation, the Akita Hematite Process has been modified continuously. Most recently, two process modifications were carried out. The first was an improved ability to maintain a lower arsenic concentration in the de-arsenic process, and the second was an increased throughput in the hematite precipitation autoclave. The details of these recent changes in the Akita Hematite Process are presented in this paper.

Jan 1, 2006

By D Maschemeyer

The cobalt production of the Chemical Metallurgical Division of Sherritt Gordon Mines Limited was supplemented, from May, 1962, to June, 1964, by processing 3,500 tons of a calcined cobalt-nickel concentrate. This paper describes the reduction roast -aqueous sulphuric acid leach process and the operating practices employed in recovering cobalt, nickel and copper from this oxidized by-product of a lead-copper operation. Incorporated in this paper is a description of how this process was integrated with the existing ammonia leach -hydrogen reduction process for the recovery of nickel and with the soluble cobaltic ammine process for the recovery of cobalt. Introduction T HE Chemical Metallurgical Division of Sherritt Gordon Mines Limited at Fort Saskatchewan, Alberta, has recently completed ten years of operation utilizing the ammonia leach process for the recovery of nickel, cobalt and copper from sulphide concentrates, matte and other materials amenable to this process. A continuing development program, along with the expansion of certain facilities, has enabled the refinery to attain a production rate of 31, 000,-000 pounds of nickel per year by hydrogen reduction. This represents an increase of approximately 85 per cent over the original design capacity of the plant.

Jan 1, 1965

By A. A. Wessels, D. P. Allison

"Mine hoists are built to handle a certain nameplate capacity; they are specified and designed according to the required duty. However, as production capacity increases in other parts of an operation, the hoist capacity can become the critical constraint. Such a situation occurred at Lundin Mining’s Neves-Corvo operation. This paper examines how each component of the existing hoisting system was examined and optimized. Through a combination of engineering study and hoist simulations, the annual hoisting capacity was improved by 24% through increases in payload capacity and available hoisting time combined with a reduction in cycle time, while no changes were made to the hoist motor, drum or headframe. The additional payload capacity was achieved by reducing the mass of the hoist ropes and skips, and improving load monitoring systems. The cycle time was reduced through the shortening of the creep distances and increased availability through the installation of a shaft collar safety platform, alternative guide rope bushes, and superior liners for both the skips and underground measuring flasks. Enhanced cooling of the hoist electrical system was also incorporated to increase hoist availability by reducing downtime during hot summer months. The changes will increase the capacity from the current 4.5 mega tonnes per annum (Mtpa) to a planned 5.6 Mtpa and are being implemented over a 2-year period whilst maintaining the mine production during the upgrade work. INTRODUCTION Neves-Corvo Mine Neves-Corvo is primarily a copper and zinc mine producing copper, zinc and lead concentrates. The operation is owned and operated by Somincor, the Portuguese subsidiary of Lundin Mining. Located in the Alentejo district of southern Portugal, the operation is situated approximately 15 km southeast of the town of Castro Verde, where summer temperatures can reach as high as 45ºC, and approximately 220 km southeast of Lisbon. The principal means of mine access is via a ramp from surface, with the vertical shaft used to hoist ore and waste from the 700 m level, while conveyors descend from the 700 m level to transport ore and waste up from the deeper levels of the mine. The mine is highly mechanized and several different stoping methods are employed, with the most significant being bench-and-fill and drift-and-fill. The Neves-Corvo mine currently exploits five orebodies: Neves, Corvo, Graça, Zambujal and Lombador for copper and zinc-lead ores which are processed in one of two plants. All the orebodies are currently exploited over their full elevation with the exception of Lombador which is only mined down to the 220 m level, approximately the top 50% of the orebody, known as Lombador Phase 1."

Jan 1, 2019

By Lawrence Devon Smith

"The concept of risk is well established in the mining industry. It is acknowledged when estimates of reserves are expressed as proven or probable, when mining and metallurgical recoveries are applied to the ore, and when contingencies are added to costs. However, it is difficult to provide a quantitative assessment of risk. The significant sources of risk in a mineral project and how these are addressed in project evaluations are discussed. The discount rate is examined as a fundamental means of reflecting risk in discounted cash flow evaluations. Current industry practice is discussed, and a methodology for the analysis of risk levels is proposed that assesses the constituent components of the discount rate: real interest, mineral project risks, and country risk.IntroductionThis paper examines the components of the discounted cash flow discount rate and proposes a method of estimating project-specific discount rates. The motivation for this work comes from experience of project evaluations in which owners and purchasers had agreed on virtually every aspect of the evaluation except how much the project was worth. Agreement was reached on reserves, grad~, recovery, capital costs, operating costs, taxes, and, by combining these components, even on the fmal cash flow values. The only difference in opinion concerned the discount rate to be used in the calculation of the net present value. Depending on the life of the project, such differences of opinion can cause a variation of more than 50% in the value placed on a project! This is illustrated in Figure 1."

Jan 1, 2003

By E. Swartzman

This paper presents a general re-view of the various methods of briquetting coals, with and without the aid of a binder, with special reference to the production of a suitable briquette from Nova Scotia 'fines' for re-blending with industrial coal. From the economic and technical viewpoints, either small stoker-sized briquettes made with about 4 per cent asphalt in standard low-pressure double-roll presses, or briquettes made without binder in high-pressure double-roll presses, appear to be the most reasonable solution at present.

Jan 1, 1959

By J. C. Gibson, C. H. Stockwell

"The San Antonio gold mine is at Bissett, Manitoba, on the north shore of Rice lake, 100 miles northeast of Winnipeg. Gold was discovered on the property in 1911, but intensive exploration was not undertaken until 1926. Milling commenced on May 1st, 1932. Total amount of ore milled from that time until the end of 1946 was 1,766,670 tons, having a value of $18,378,317.GENERAL GEOLOGYThe rocks in the vicinity of the mine are Precambrian and include three groups, namely, the Rice Lake series of volcanic and sedimentary rocks, basic and acidic intrusions, and a younger formation of sediments known as the San Antonio formation (Fig. 1). The lower part of the Rice Lake series, consisting of flows of rhyolite, trachyte, and andesite with interstratified beds of agglomerate, occupies an area extending southward from Rice lake. The lake itself and the country to both east and west of its northern end is underlain by the next succeeding beds of the series, which are chiefly tuffs, arkose, and conglomerate, but include a thin band of basalt. Northward from the lake, these are succeeded by the upper beds of the series, first a thin band of basalt and, overlying this, porphyritic andesite flows interlayered with beds of volcanic breccia or agglomerate.The Rice Lake series has been invaded on the east side of the lake by a body of basic rock ranging in composition from gabbro to diorite and quartz diorite, now much altered. This is cut by younger sills and dykes of basic rock, probably diabase, the original texture of which is largely destroyed by alteration. Numerous dykes of feldspar porphyry, quartzfeldspar porphyry, and a few of a rhyolite-like rock, occur south of the lake, but are uncommon to the north. They cut the diabase and older rocks.Extending westward from Rice lake and lying with marked angular unconformity against all of these rocks is the San Antonio formation, consisting of cross-bedded, arkosic quartzite."

Jan 1, 1954

By F. L. Casey

"Part 1 – Published Papers Baria, G., and Boshkov, S., ""Insights into Undercuttingin Block Caving"", Proc. 5th Rock Mech. Symp.,Mines Br. - Information Canada, 41-58, 1970.Barron, K., Coates, D. F., and Gyenge, M., ""ArtificialSupport of Rock Slopes'', Mines Branch ResearchReport R228, July, 1970.Barron, K., ""Criteria for Brittle Fracture Initiation inand Ultimate Failure of Rocks and Their Applicationto Fracture Zone Prediction"", Proc. 2ndCongr. Int. Soc. Rock Mech., Belgrade, 1970, 3-37.Bauer, A., and Calder, P. N., ""Projectile Penetration inRock"", Proc. 5th Rocle Mech. Symp., Mines Br. -Information Canada, 157-170, 1970.Bauer, A. M., ""Site Development and Rehabilitation ofPits and Quarries"", Canadian Mining Journal,Vol. 91, No. 7, 77, July, 1970."

Jan 1, 1971

By B. Yu, Y. O. Oyediran, M. Robart

"This paper presents the latest flotation development testwork conducted in 2015 on the ‘B Zone’ samples from the Strange Lake Alkalic Complex (SLAC). Since the discovery by Iron Ore Company of Canada (IOC), metallurgical development has been under taken by a number of mining companies targeting various value metals, including yttrium, zirconium, niobium, and rare earths.Most recent, Quest Rare Minerals Ltd. (Quest) completed a Pre-Feasibility Study (PFS) in 2013 where the flowsheet was relatively complex and led Quest to explore alternative options. In 2014, the PFS flowsheet was simplified and one of the features introduced was pre-concentration by rougher flotation. The combined rougher flotation concentrate and slimes successfully recovered >90% TREE in 60% mass thus reducing capital cost and technical risks of the downstream hydrometallurgical processes. The latest flotation development testwork focused on achieving a pre-concentrate in which >80% TREE are recovered in 20% mass. Two separate reagent schemes, based on an ester phosphate collector (Clariant 1682) and a benzoylhydroxamic acid collector (Florrea 7510), were developed. Parameters evaluated in the development testwork included desliming, secondary yttrium and zircon collectors, depressants, temperature, conditioning temperature, time, and density, pH, sodium silicate type, cleaning, and flowsheet configuration. Both developed reagent schemes achieved the targeted metallurgy.INTRODUCTIONThe Strange Lake Alkalic Complex (SLAC) was discovered after geological survey and mapping studies by Geological Survey of Canada and Newfoundland and Labrador Department of Natural Resources between 1967 and 1980. Subsequent exploratory drilling programs by Iron Ore Company (IOC) in the 1980s found that the REE and high field strength element (HFSE) mineralization were within the central region of the SLAC which was named A Zone by IOC and later renamed Main Zone by Quest Rare Minerals Ltd. (Quest). Additional exploratory drilling outside the Main Zone by IOC and later by Quest, led to the discovery of B Zone, which was recognized as the most significant deposit of rare earth elements, yttrium, and zirconium in the SLAC. The B Zone Indicated Resources are estimated at 278.13 Mt at 0.93% total rare earth oxide (TREO) and Inferred Mineral Resources are estimated at 214.35 Mt at 0.85% TREO (Oyediran et al., 2014)."

Jan 1, 2016

By C. L. Popp

The scope is to address issues confronted by parties in the mining industry such as: Mine planners, survey and engineering departments, field teams and subcontractors. Describing approaches and best practices for assembling a project team to identify and create modeling requirements and to implement beneficial results. 3D Machine Control and Guidance tools continue to reduce project risk and attract quality resources with skill sets new to the earthmoving industry. These tools increase production, reduce rework and help with government permitting.

May 1, 2013

By Reis. E., P. Pino Véliz

"Along the process of defining the fundamentals of a ferronickel project, several questions require proper answers from the very beginning such as the size and characteristics of the laterite deposit (oxide or silicate), the mineralogical variability, and the selection of the most valuable process route. In general, these elements will be defined along the progress of the exploration and feasibility studies, and definitive engineering. Also, from the very preliminary estimates, three questions are very common: what should be the plant capacity (annual tonnes of contained nickel), what will be the probable capital required (CAPEX), and what will be the estimated timeline (schedule) between the initial stage, say the feasibility study and the plant start-up and ramp-up to designed capacity. The accuracy of the capital cost estimates also progresses along the different stages of development from ±50% at the Preliminary Economic Assessment (PEA) stage down to ±5% for the Detailed Engineering and Construction stage. These accuracies of estimates have been, in some ways, accepted by the mining community and investors. The industry accepted benchmark for ferronickel projects in terms of CAPEX are then in the order of US$50,000 per tonne of nickel contained in the FeNi product. In this paper, the authors analyze in some details three ferronickel projects for lateritic ores that have selected the Rotary Kiln - Electric Furnace (RKEF) as the suitable technological route and have started production in the period 2006–2016. Some key aspects of the ferronickel projects are examined: 1) size and type of deposit; 2) flowsheet selection; 3) evolution of capital cost as a function of capacity from the feasibility stage to construction; 4) comparison between planned production scale and actual ramp up; 5) estimated capital expenditure (CAPEX) compared with actual figures; 6) nickel price evolution and timing of the approval for the project to proceed to construction and production start-up. The objective of this paper is to identify key elements that should be addressed in future projects and that are proposed as benchmark figures for similar projects."

Jan 1, 2017

By W. P. Campbell

In the course of the development of the Red Coulee field, northwest of Coutts, Alberta, a considerable amount of information has been gathered by the Department of the Interior regarding the chemical character of waters encountered in the drilling of wells in this area. The writer, in this paper, has undertaken to assemble the available material with the idea of deducing what relations, if any, may exist between the different waters from the same well, and also how these compare with waters encountered in similar horizons in other wells. From no other district, with which the Department of the Interior has had to do, have there been received so many samples of water, and yet not all the waters logged in the drilling reports were sent in for analysis. The information, therefore, herein contained is not as complete as the writer would have desired, but sufficient evidence has been accumulated to indicate some very definite tendencies in the chemical nature of the waters of this field. The drilling of Red Coulee wells has been carried out exclusively by percussive tools. These permit 'dry' drilling, and, consequently, water-sands are recognized when encountered. Had rotary tools been used, information regarding water-sands would have been very meagre, if not entirely lacking, since, in the mudding-off process, water-sands would have been overlooked, with the result that, should water break through into a completed well, its source would not be known and remedial efforts would be greatly handicapped, if not entirely defeated.

Jan 1, 1931

By Patrick Wong, Gareth Hatch, M. A. Halim, V. I. Lakshmanan, Darcy Tait

"This paper describes development of an integrated chloride process for separation and purification of REEs. The process includes atmospheric leaching of ore/concentrate with mixed chloride lixiviant containing HCl and MgCl2 followed by bulk recovery of REEs, dissolution of the bulk intermediate product, and separation of individual REEs by solvent extraction (SX) process steps. Mixed chloride leaching technology provides the opportunity to regenerate the lixiviant, while the addition of MgCl2 in HCl enhances the hydrogen ion activity by orders of magnitude increasing REE extraction efficiency at a lower concentration of HCl. An individual REE separation process developed by Innovation Metals Corp. is being piloted at a state-of-the-art facility at Process Research ORTECH Inc. in Mississauga, Ontario, Canada. The SX process includes the separation of light REEs (La – Nd), medium REEs (Sm – Gd) and heavy REEs (Tb – Lu plus Y) from leach liquor followed by individual REE separation. Each SX circuit proceeds by multistage extraction followed by scrubbing and stripping. The process is chloride based and reagents are recycled, reducing waste generation and optimizing water usage to reduce environmental impact.INTRODUCTIONRare earth elements (La to Lu plus Y) exhibit a range of unique magnetic, electronic, catalytic and optical properties. Due to these special properties, the application of REEs is increasing and they are found in components for wind power generation, hybrid electric cars, catalytic converters, and many electronic devices.Rare earth elements (REEs) are commonly divided in two groups: light rare earth elements (LREEs) and heavy rare earth elements (HREEs). Light rare earth elements include elements from lanthanum (La) to neodymium (Nd). Although promethium (Pm) is considered an LREE it is unstable and scarcely occurs in nature and is generally excluded. Heavy rare earth elements include elements from samarium (Sm) to lutetium (Lu) plus yttrium. Although rare earth elements are not rare and the rare earth oxides are scattered around the globe, over 95% of REEs+Y are currently produced in China (Pitts, 2011). On one hand the Chinese government is restricting the export of rare earth elements and on the other hand the demand for REEs+Y is increasing in the rest of the world. This has created an imbalance in the supply and demand of rare earth elements and has led to a rush for developing new rare earth projects."

Jan 1, 2016

By S Grönstrand, C. Perez, A. B. Yañez, F. Coddou, P. Morales, H. Elgueta

"The TankCell® 300 forced air flotation cell designed and built by Outotec, with active volume of over 300 m3, was installed at Codelco’s Chuquicamata concentrator in September 2008. After that, a program was conducted, where the new cell was tested against the plant’s existing flotation cells of type TankCell® 160, with an active volume of over 160 cubic meters.Testing program was exhaustive and detailed. Grade-recovery curves for each setup were reported, along with recoveries by particle size. Secondly, operational characteristics like air feed and froth height setpoints, and power consumption are compared side-by-side. As the third topic, gas dispersion characterization included velocity mapping, holdup, bubble size and bubble surface area flux operating range. The fourth area of interest was the retention time distribution (RTD) of the 300 and 160 m3 cells in comparison. A detailed campaign using radioactive tracer tests was conducted to clarify this.All of the investigations mentioned above are reported in separate papers for more detail. The aim of this paper is to collect the key findings, and present them in real terms, always referring to operability and metallurgy of the cells. It is destined for people designing new plants and to those improving and expanding existing ones. The most frequently heard question is: will the new large cells operate at same efficiency as the smaller ones. In short, the answer is: NO. They operate at improved efficiency!INTRODUCTIONIn the last two decades of minerals processing, there have been three dominant trends of development in the flotation technology: equipment scale-up, cell characterization and circuit modeling. Equipment scale-up has been rapid in the past two decades. In the year 1990, the largest flotation cell in use was 50 cubic meters of size. This year, 300 cubic meters is the largest installed cell. Characterization of flotation equipment and circuits is a very popular subject nowadays and has helped many operations to improve their recoveries through better control strategies, for example by using optimized air feed and level control profiles (Gorain, 2005), (Doucet, Gomez, Finch, 2006), or through better maintenance (Coleman, Urtubia, Alexander, 2006). Characterization work is closely linked to circuit modeling. The aim is to produce sufficient amount of data to allow reliable model building. These models are then used to design new circuits and to improve existing ones. So in summary, these three lines of development have slightly different aims – from capital and operational cost to performance optimization. Ultimately, they converge in the same end result – maximizing the profitability of the operation. Following chapters will summarize the extensive test work and scientific studies at Codelco Chuquicamata. The aim was to compare a TankCell® 300 cell, with nominal volume of 300 m3, against two TankCell® 160 machines, with 160 m3 volume in each. The work should yield answers to questions: does the larger cell produce similar results – is the scale-up successful?"

Jan 1, 2010