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By P. Ashtari

Influence of Sr and Mn single and combined additions on the modification of the Fe-containing intermetallic compounds and mechanical properties of Fe-rich AA319 aluminum alloys have been investigated, The microstructural features e,g, morphology of the Fe compounds and eutectic Si has been correlated to the mechanical properties, It was demonstrated that modification of the Fe compounds from the platelet ß-Al5FeSi to the Chinese script a-Al8Fe2Si compound improves the UTS and elongation of the alloys by 10.3% and 83.9%, respectively. Moreover, the simultaneous modification of the Fe compounds and eutectic Si increases the UTS and elongation of the alloys by 15,3% and 116,1%, respectively.

Jan 1, 2005

By Haipeng Li, Jacob Masliyah, Barun Gorain, Jian Huang, Qingxia Liu, Zhenghe Xu, AuTec Innovative Extractive Solutions Ltd.

"Froth flotation is widely used to selectively separate one or more minerals from an ore over a wide range of particle sizes with high efficiency. Bubble–particle attachment is one of the most critical steps in flotation. The objective of this project is to demonstrate the need for an innovative dual bubble generator to improve flotation efficiency. This dual bubble generator was designed to generate two different sizes (micron size and typical flotation size) bubbles. The micron size bubbles generated on the crevices of particle surfaces in venturi type of cavitation tubes enhanced the attachment of fine particles to the bubbles in conventional flotation systems. They also acted as a secondary collector, which has the potential to reduce operation cost and improve flotation recovery. The dual bubble generator was evaluated for a double refractory gold ore with 3g/t Au, 1.5 wt% TCM (total carbonaceous matter) and 0.7 wt% sulfides. The results were compared with those obtained using a commercial bubble generator. Compared with the commercial bubble generator, the dual bubble generator showed not only a higher gold recovery, but also an improved separation efficiency, demonstrating the potential of dual bubble generator in fine particle flotation.INTRODUCTIONFroth flotation has been widely used in mineral processing and waste water treatment. However, flotation has been proven inefficient for fine particle recovery although it becomes increasingly inevitable to process fine particles with the depletion of easy processing ores. The critical problem of fine particle flotation is the low attachment of fine particles to flotation size bubbles due to their low collision rate. Based on a commonly acceptable flotation model given by R =F*[Pc*Pa*(1-Pd)], the probability of bubble–particle collision (Pc), attachment (Pa) and particles detachment from air bubbles (Pd) collectively determines fine particle recovery (R) (Yoon and Luttrell, 1986). Since Pc = (3Dp/Db) where Dp and Db are diameters of particles and bubbles, respectively, bubble size and particle size impact the bubble-particle collision in opposite directions. It is evident that the probability of bubble–particle collision decreases with decreasing the size of particles, leading to a low recovery of fine particles. In this case, reducing the bubble size and/or increasing the apparent size of particles by fine particle aggregation are clear means to improve fine particle recovery."

Jan 1, 2016

By Reinis Sipols

AGENDA ? Introduction ? Definitions and Key features ? PEA - Preliminary Economic Assessments ? PFS ? Preliminary Fesibility Studies ? FS ? Feasibility Studies ? Costs and Risks ? Cash Flow, Economic Analysis and Reporting ? Recommendations for Improved FS accuracy INTRODUCTION ? The reporting of material information on mineral deposits has been governed by NI 43-101 legislation for almost a decade. ? The investment sector depends on the independent, professional QP to provide objective observations, comments and recommendations through all levels of geological, engineering and financial evaluation until a mine construction decision has been made.

May 1, 2013

By Neville Jordison

Indirect, gravity flow, heat exchangers have become a well established technology in mineral and metallurgical process plants. The technology is a conventional heat exchanger using high efficiency plates, with a free flowing bulk solid on one side of the exchanger and a fluid on the other side. This simple concept leads to many opportunities for achieving greater energy efficiencies in process plants. Indirect heat exchange is much more efficient than direct heat exchange using air such as in a fluid bed or rotary device. When air is used directly, large fans are required, it may also be necessary to chill the air, both high consumers of energy. By contrast, using water as the cooling medium requires only low horsepower pumps, typically only 10% of fan HP. Furthermore there are no stack emissions with the requirement for removal of dust or emissions. Indirect heat exchange also creates the opportunity to recover energy. This can work in two ways: energy can be recovered from a hot bulk solid, to heat pressurized hot water for steam generation or preheat air. Alternatively recovered energy from elsewhere in the plant in the form of hot water, steam, air or thermal oil can be used to preheat a bulk solid.

Jan 1, 2011

By W. K. Chan, R. Lahaie

"The Suncor Oil Sands Mine located north of Fort McMurray, Alberta, produces about 80000 m' per day of tailings waste which must be disposed of economically in an environmentally acceptable manner. To date, this has been accomplished by impounding the high water content tailings wastes behind large dykes, many of which approach 100 m in height .The dykes are constructed using suitable overburden material stripped prior to the mining of the oil sands feed and/ or the coarse sandy fraction of the tailings waste itself. Although the above is common practice at many mining operations, the large volumes handled and the resultant costs require designs to be meticulously fine-tuned toward the optimum. As a result, considerable effort is expended on planning, designing and construction, and performance monitoring. The lack of precedent experience (Suncor pioneered oil sands mining), coupled with the realities of long, harsh winters and a variety of troublesome site conditions and construction materials, has led to some very unique dyke construction.This paper overviews current tailings disposal plans as welt as some of the key issues related to the design, construction and performance of these large dykes."

Jan 1, 1988

By M. G. Stamatakis, C. Zagouroglou, C. Helvaci, J. Kanaris

"Abstract -Borate minerals, such as colemanite, ulexite and borax, have been reported in Tertiary continental basins of West Anatolia, Turkey, and Samos Island, Greece.Tuffaceous rocks interbedded with the borates are rich in authigenic silicate minerals such as zeolites, potassium feldspar and opal-CT, all of which have a genetic association with the borates. Chemical analyses of the tuffaceous rocks show variation in major elements due to the varying percentage of carbonaceous, detrital, and volcanic derived material.The volcanic activity in the vicinity of each particular lacustrine basin created ion-rich fluids from which a series of borates were precipitated under arid climate. Additionally, the saline-alkaline character of these fluids was responsible for the diagenesis of the silicic glass of the tuffaceous rocks, altering them to silicates and silica polymorphs."

Jan 1, 1993

Agenda ?Introduction ?Geology ?Mining ?Metallurgy ?Process, Layout ?Environmental Background ?Kinross Gold Corporation owns the Lobo-Marte gold property, located in Region III of northern Chile. ?The property is close to two other Kinross mines, Maricunga 50kmto the south and La Coipa 60km to the north, plus a regional office in Copiapo and district level operating synergies are expected. ?Lobo and Marte were discovered in the early 1980s and are intrusion-hosted, porphyry-type precious metal deposits, typical of the Maricunga District. ?The Marte open pit heap leach mine was in commercial production in late 1988, but was suspended in February 1992 as it did not meet forecasted production levels and recoveries. ?Kinross plans to recover ore from the Lobo and Marte deposits through an open-pit, heap leach47,000tonne per day operation.

May 1, 2010

By P. Leo

Al-Mg-Si alloys are widely used as medium-strength structural materials; extrusion is the most common processing route. In the present hot deformation investigation of a 6060 alloy, the microstructure of the alloy has been analyzed in the as-cast state, after homogenization heat treatment and after hot deformation by tensile tests in the range 400-490°C and 10-4 to 10-2s-1 on both as cast and homogenized alloys. After deformation the microstructure of the as-cast alloy exhibited cavitation. The flow curves at the lowest test temperature T show a gradual softening after a stress peak, being more evident for the alloy deformed in the homogenized state in association with a high yield stress; at higher T a plateau is attained which is lower as T rises and strain rates decrease. For each fixed T, the ductility decreases as strain rate increases for the homogenized alloy whereas, for the as cast alloy, it rises with strain rate. Constitutive analysis gives Q = 240kJ1mol for the homogenized alloy in agreement with published values; this indicates a more rapid strength decline with rising T than Al, suitable for good hot workability along with the lack of cavitation.

Jan 1, 2011

By W. A. Jankola, M. T. Martin

"The world's first zinc pressure leaching plant at Cominco's Trail operations started production in 1981. Sullivan zinc concentrate is leached at the rate of 190 tpd in a four-compartment autoclave at elevated temperatures and oxygen pressures to produce a zinc sulphate solution and elemental sulphur. Zinc extraction exceeds 98% and sulphide to elemental sulphur conversion exceeds 95%.The sulphur is recovered from the discharged slurry in the underflow of a hydrocyclone, and is upgraded as a flotation concentrate. The concentrate is dewatered, melted and filtered to produce a polished sulphur product of better than 99% purity. An alternative sulphur recovery process employs an unique sulphur separation method that recovers over 90% of the sulphur in the molten state. The remaining sulphur is recovered by flotation following flash discharge of the slurry. The product slurry containing the zinc sulphate solution and the iron-lead residue joins the existing roast-leach zinc plant for purification and zinc electrowinning.IntroductionIn 1981, Cominco Ltd. commissioned the world's first commercial zinc pressure leaching plant at their Trail operations in British Columbia. As part of a $700 million modernization and expansion program for lead and zinc started in 1977, the company installed the first o f two autoclave trains.Prior to pressure leaching, zinc production was closely tied to acid and fertilizer production. Sulphur dioxide produced from roasting the concentrates had to be converted to sulphuric acid. Thus, any expansion of zinc operations with the roast-leach technology would have required extensive modifications to the acid and fertilizer plants as well as to the roasters. Zinc pressure leaching, on the other hand, offered a one-step dissolution of zinc from the concentrates with high extraction, and production of elemental sulphur. The associated dust and sulphur dioxide generated in the roasting process are both eliminated from the working environment of the pressure leach facility. The flexibility allowed by producing elemental sulphur, and the opportunity to break the sulphuric acid link for about 25 per cent of the targeted 272,000 tonnes per year zinc production was very appealing. The process was successfully demonstrated at a pilot plant in 1977(1-6)."

Jan 1, 1985

By H. Sahay

"DISCLAIMER NOTICEThe views and conclusions contained in this presentation are those of the author and should not be interpreted as necessarily representing the official policies or recommendations of the Department of Mines and Energy, Government of Newfoundland and Labrador. ABSTRACTThis paper describes the main testing procedures that should be carried out to evaluate the capacity and capability of the service brakes on the large-size diesel-electric trucks now in common use at open-pit mining operations. Brake testing programs in general are described, and then consideration is given to different techniques of service brake testing, brake performance evaluation, braking energy and typical performance characteristics.IntroductionThe first diesel-electric truck with a capacity of about 85 tons was introduced in 1963 by Unit Rig and Equipment Company of Tulsa in cooperation with General Electric Company, who successfully developed and supplied the most important component- motorized wheels. Since then, its popularity and numbers have continued to grow, and now more than 3700 such units are in operation in mines around the world. In Canada alone, their number is more than 700, including about 150 in the Province of Newfoundland and Labrador. Similarly, their size has also grown from that initial capacity of 85 tons to 350 tons.Although the introduction of the electric trucks proved to be invariably economical, their indiscriminate use was not without severe consequences. Many runaways and even fatalities occurred when the dynamic retarder failed while the truck was travelling loaded down severe grades. The service brakes in such cases proved incapable of stopping runaway trucks, mainly due to their limited capability and the fading caused by excessive heat produced during the act of braking itself. This eventually led the various governments, the open-pit operators and the manufacturers to seriously question the braking capability as well as function of both service brakes and dynamic retarders. Extensive testing"

Jan 1, 1980

By Ron Zevenhoven

In Finland one opportunity for large-scale CO2 capture, utilisation and storage (CCUS) is CO2 mineralisation, i.e. mineral carbonation. A process route under development towards industrial application involves production of magnesium hydroxide or sulphate from serpentinite rock (serpentine = 3MgO·2SiO2·2H2O), followed by conversion either in a pressurised fluidised bed (PFB) reactor, giving magnesium carbonate, or in an aqueous solution process giving magnesium hydro-magnesites. Iron present in the rock is typically obtained FeO(OH). Results obtained with these process routes and progress towards industrial demonstration is addressed, process heat integration and operation on flue gases (without CO2 pre-separation!) being key features for economic viability. A process route utilizing calcium-containing slag by-product from iron- and steelmaking under development towards large-scale application is the so-called slag2pcc concept. It converts an industrial by-product into valuable material, reduces use of natural material and streams to landfills while binding CO2 produced by the process generating the slag. Using ammonium salts, calcium is extracted from steel converter (BOF) slags and subsequently carbonated in a two-stage aqueous process (at ambient temperatures and pressures). Precipitated calcium carbonate (PCC) is produced while regenerating the ammonium salt. Process performance and scale-up while guaranteeing a certain PCC quality are presented.

Jan 1, 2015

By M. C. Ethier, A. L. Laramie

"The Granisle and Bell Copper mines were officially put into production in 1966 and 1972, respectively. The Granisle Mine was purchased in late 1979by Noranda and the two operations were amalgamated as one division. Both mines were closed in 1982after sustaining heavy financial losses during a period of low copper prices beginning in 1981.This paper describes the resumption of operations at the Bell Mine in 1985 after its shutdown period of three years and the dramatic and sustained improvements in productivity and efficiency realized as a result of a commitment by employees and management to the application of Participative Management and Employee Involvement principles. After a general description of the effects of such a philosophy on the operation as a whole, and a comparison to the operation's last full year as a producer, it deals with the practice of this philosophy in the maintenance department at the Bell Mine and the superb results realized.IntroductionThe Bell Copper deposit was discovered in 1963 and came onstream as a 10000 ton s per day open pit mine in the fall of 1972. Identified reserves at that time were 46 million tons of ore containing 0.50% copper. The mine shared facilities of the townsite of Granisle with the nearby Zapata-Granby mine which had established the community six years earlier.Because of easy grinding ore and improvements to milling circuits, Bell's throughput rate was increased to 17 000 tons per day by the late 1970s. In the open pit, improvements resulted in mining of additional reserves with higher stripping ratios. At startup, a half ton o f waste was mined for every ton of ore processed.By the end of 1982, with 48.2 million tons already mined, the Bell Mine had identified additional mineable reserves of 39.4 million tons containing 0.52% Cu.In November 1979 the Granisle Mine was purchased from Zapata-Granby. The two mines, with a total of 700 employees, were operated under common management as the Babine Division until 1982 when low copper price s forced the closure of both for an indefinite period.The outlook for copper prices remained bleak and only 50 people were retained on the payroll to maintain the two plants, most of them working on a part-time schedule.The population of the Village of Granisle dwindled from over 1500 inhabitants to under 500, as people moved away to seek other employment.Prior to the shutdown, the Bell Mine employed 370 people and pit extraction averaged nearly 50000 tons per day of which 16000 tons was mill feed, and the remainder waste. Total cost to produce a pound of copper was C$1.36 in 1982."

Jan 1, 1990

By A. Oja, M. Lahtinen, P. Salonen, B. Saxen

Most of the secondary and low grade zinc raw materials cannot be treated successfully by either conventional roasting - leaching - electrowinning (RLE) process or even by atmospheric direct leaching process. The problems arising especially from high impurity content of these raw materials can be effectively solved by implementation of the solvent extraction process. The utilization of solvent extraction process has been demonstrated by Outotec with raw materials like Waelz oxide, crude zinc oxide and zinc containing concentrator tailings. Based on batch and continuous test work it has been shown that SHG quality zinc can be produced even from the lowest grade raw materials. Impurity control in the solvent extraction process has been examined. The solvent extraction process is the key feature of the whole zinc plant for such raw materials. However, design of the entire zinc process including neutralization and bleed treatment is important for optimization of investment and operation costs of the plant. Very careful evaluation of the zinc process with modern simulation tools is essential. The optimized Outotec zinc process ensures a sustainable and profitable process containing minimal effluent and requiring little residue treatment.

Jan 1, 2014

By Åke C. Rasmuson, Mahmood Alemrajabi, Kerstin M. Forsberg, Kivanc Korkmaz

"In the present study the recovery of a Panasonic Prismatic Module 6.5 Ah NiMH 7.2 V plastic casing hybrid electric vehicle (HEV) battery was investigated, separately processing the anode and cathode electrodes. The composition of the electrode materials was determined by total dissolution and analysis using ICP-OES. Nickel is the dominant metal in the active materials (65% by mass in the anode and 70% by mass in the cathode). Most of the rare earth elements (La, Ce, Nd, Pr and Y) are located in the anode active material, whereas only a small amount of Y is found in the cathode material. The electrode materials were further characterized by SEM-EDS and powder XRD. The electrodes were leached in sulfuric acid and in hydrochloric acid under different conditions. The dissolution was followed by taking out samples and analyzing the concentration of REE, Co, and Ni using ICP-OES. The results indicate that the dissolution of nickel could be limited by slow dissolution kinetics of nickel oxide. Further, it was found that light rare earths are lost through precipitation during sulfuric acid leaching with increasing extent as the temperature and sulfuric acid concentration increases. The separation of REE from the sulfuric acid leach liquor by precipitation as NaREE(SO4)2.H2O and from the hydrochloric acid leach solution as REE2(C2O4)3.xH2O have been studied by performing experiments using battery leach liquors. INTRODUCTIONIt is well known that the Hybrid Electric Vehicle (HEV) is becoming more common due to economic and environmental reasons. Batteries are widely used in HEVs’ such as automobiles or larger trucks for transportation purposes. The most common type of battery in these vehicles is nickel metal hydride (NiMH), largely due to Toyota's decision to use them in their popular Prius. More than two million hybrid cars worldwide are running with NiMH batteries, such as the Prius, Lexus (Toyota), Civic, Insight (Honda), and Fusion (Ford). Panasonic manufactures HEV prismatic NiMH batteries that have been used by Toyota and GM (among others), while Sanyo manufactures HEV cylindrical cell NiMH batteries, which have been used by Honda and Ford."

Jan 1, 2016

By J. V. Thirgood

"Reclamation legislation was introduced in British Columbia in 1969 amidst public concern and controversy. This paper reviews this legislation as it relates to coal mining, and how it is being implemented.Although the principles of land reclamation are reason-ably well understood, reclamation of industrial wasteland has never previously been attempted under such rugged conditions as occur in the Canadian Rockies and a new methodology is being developed.The resolution of the technical and organizational problems involved are discussed and the techniques and experiences described."

Jan 1, 1971

By Robert MacPhail, Louis Racine, Bret G. Cousins

"Sodium Isopropyl Xanthate is employed in a wide variety of sulphide flotation procedures due to the specificity over other xanthates and the cost savings over other sulphide collectors such as thionocarbamates, xanthogen formates and dithiophosphates. An investigation carried out by Tennants Research Technology Applications (TRTA), has produced a chemically enhanced SIPX that has shown all the advantages of normal SIPX along with improved recoveries.Currently, FLEX 31 is manufactured at the Prospec Chemicals xanthate plant in Fort Saskatchewan, Alberta, Canada. Prospec, founded in 1983, produces approximately 4500 tonnes of xanthates per year and is presently undergoing expansion to produce approximately 6000 tonnes. The proprietary process for FLEX 31 is a new addition to plant operations that include the production of xanthates, thionocarbamates and xanthogen formates.This paper will cover the testwork on the zinc flotation circuit at the Louvicourt Mine in Val d'Or, Quebec. This testwork indicated that FLEX 31 could replace SIPX due to the ability of the FLEX to improve zinc flotation kinetics without adversely affecting final concentrate grade. FLEX has presently replaced SIPX in the zinc circuit at Louvicourt.BackgroundThe Louvicourt deposit is hosted by greenschist facies Archean volcanic rocks located in the southeast portion of the Abitibi Greenstone Belt. In the Val d'Or area, the volcanic rocks form an east-west striking, steeply dipping and south-facing sequence composed of thick mafic and ultramafic flows of the Lower Malartic Group.The joint venture has three partners-Aur Louvicourt Inc. (30%), Novicourt Inc. (45%) and Teck Corp (25%). Aur Resources holds 30% interest through Aur Louvicourt, a wholly owned subsidiary and is the operator of the project. Novicourt Inc. is 60.9% held by Noranda.Approximately 75% to 85% of Louvicourt's revenue comes from the sale of copper; 10% from gold (in the copper concentrate); 7% from zinc and 3% from silver (also in the copper concentrate) The copper at Louvicourt is fairly ""fast floating"". About 60% of the copper in the ore can be concentrated in the first flotation cells with feed grades of approximately 4% copper.The initial testwork and pilot trials had indicated that it would be difficult to achieve zinc grades over 52% and recoveries would have to be kept at a level amenable to salable concentrate grades. The actual mill results, with a fine regrind, achieved zinc grades of 55% to 56% at about 75% recovery."

Jan 1, 1996

By Matt Manson

?? Current Exploration and Assessment ?? Overview of Potential Development ?? Infrastructure ?? Opportunities and Challenges ?? Renard? 1-10 kimberlite pipes and ?Lynx-Hibou? kimberlite dyke system within ?Foxtrot? property ?? 50/50 Joint Venture between Ashton (a subsidiary of Stornoway) and SOQUEM ?? Discovered 2001-2003 ?? Québec is routinely assessed as one of the top mining jurisdictions in the world ?? Agnico-Eagle Mines Ltd. Is Stornoway?s largest shareholder and a leading mine developer in Québec

May 1, 2008

By J. O. Marsden

Over the past eight years, Phelps Dodge (a division of Freeport-McMoRan Copper and Gold, Inc.) has developed a suite of proprietary hydrometallurgical processes for the treatment of copper concentrates as an alternative to conventional smelting and refining technology. The technical viability of two processes has been commercially demonstrated in a large scale plant at Bagdad, Arizona, designed to process approximately 52,500 metric tons per year of concentrate containing 30.5% copper. The first process utilizes high temperature (225°C) pressure leaching, followed by countercurrent solid-liquid separation, and then blending of the copper-bearing solution with low grade stockpile leach solution for subsequent treatment by SXlEW for copper recovery. The second process uses super-fine grinding, medium temperature (l60°C) pressure leaching, followed by solid-liquid separation, and treatment of high grade copper-bearing solution by direct electrowinning to recover the bulk of the copper values. The latter process will be utilized at Morenci in a commercial facility designed to treat mixed chalcopyrite-chalcocite-covellite concentrates. This facility is scheduled to start up in 2007. Other flowsheet options have been developed by Phelps Dodge for application to a variety of concentrate materials in specific situations. Examples of various flow sheet options are presented in this paper, and the advantages and disadvantages associated with each are discussed in detail.

Jan 1, 2007

By E. Thomson

This type of microscopic investigation, although still in its infancy, has already found practical applications in several different phases of mining activity. The study of the transparent minerals in rocks, by means of the ordinary petrographic microscope, has for long been a very useful supplement to observations in the field, but the opaque minerals, until recently, have had to rest content with a more or less superficial determination with the hand-lens or the blow-pipe. In a great many cases, particularly where the association of metallics has been somewhat complex, this has been entirely inadequate, and the determination of these opaque minerals under the micro- scope, has opened up a new field of scientific investigation that bids fair to surpass, in practical value at least, the micro-scopic determination of the rock-forming minerals. As the details of this kind of microscopy are possibly not entirely familiar to all mining men, it might be well to outline them very briefly before dealing with the practical directions in which this method may be applied. The ordinary petro-graphic microscope, with but one extra attachment, will serve for this work. A small reflecting device, called a vertical illuminator, is inserted immediately above the objective lens. This reflects the light down to the surface of the specimen and from here the light is directed up the middle of the microscope tube to the eye. As it is desirable that the maximum amount of reflection should be secured from the surface of the section, it is first polished and set in a position perpendicular to the vertical axis of the microscope.

Jan 1, 1924

By D. Rylander

The operation of Quarry and Aggregate sites are similar to factory production, since it contains sequential production processes, tasks and activities to produce the output product. Compared to the plant though, the quarry processes are generally not synchronized and controlled towards the overall throughput of the site in real time. Some quarries control parts of the production but do generally not utilize real-time technologies for the whole site and all its activities. This fact indicates a general improvement potential in increased productivity at quarry sites, but also unsolved challenges for the same reason. The main contribution of this paper is the presentation of a Lean based method for how to describe the processes to identify control improvement potential within a site. The aim of the identified improvements is to increase overall site productivity by optimizing site, fleet and machine utilization towards the overall throughput, and minimizing operational expenses and inventories. Further the paper exemplifies the method?s usability with field studies at operational quarry plants successfully identifying and quantifying potential wastes and improvements. In addition the identified productivity improvements based on increased control and automation indicate challenges and needs in wireless communication and sensing technologies.

Aug 1, 2013