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By B. K. Mishra, Avijit Biswal, B. C. Tripathy, Abhijeet Singh, K. Sanjay, T. Subbaiah

We studied theeffect of anode substrates such as pure lead (Pb), lead antimony (Pb-Sb), and lead-silver (Pb-Ag) on the structural and electrochemical properties of electrolytic manganese dioxide (EMD). X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), and chemical analyses were used to determine the structural and chemical characteristics of the EMD samples. The charge-discharge profile was studied in 9 M KOH using a galvanostatic charge-discharge unit. In all the substrates the current efficiencies were more than 99% except with Pb-Sb where it was 90%. Results revealed the nature of the substrate strongly affected the morphology of the deposited material which in turn affected the electrochemical properties of the EMD samples. XRD analyses revealed that the nature of the anode did not affect the crystal structure of the deposited EMD and all the samples were predominantly ?-MnO2, which is electrochemically active for energy storage applications. The EMD deposited on lead substrate showed superior discharge capacity of 245 mAhg-1 when compared with other substrates.

Jan 1, 2014

By P. G. Thornhill

EARLY in 1951, Falconbridge undertook a research program aimed at the development of a sulphate roasting process for the recovery of the non-ferrous rnetals from the nickeliferous pyrrhotite fraction of Falconbridge ore, in order to reduce the tonnage of iron entering the srnelter. Such a method, it was hoped, would permit a high recovery of the nickel from pyrrhotite otherwise entering the smelter feed, thus not only raising the grade of the latter and reducing its iron content, but also providing an iron oxide residue useful as a source of by-product iron ore. At an early stage in the exploratory laboratory test work it was found that the degree to which the nickel could be solubilized by the sulphating roasting treatment was limited by particle size and the ex-tent to which the pyrrhotite concentrates were freed of the nickel occurring as physically separable pentlandite, a mineral relatively difficult to roast. ( 1) Thus the program

Jan 1, 1961

By J. Fujioka, Y. F. Gu, C. Cui, D. Ping, A. Sato, H. Harada

"A new kind of cast & wrought (C&W) Ni-Co base superalloys named as ""TMW alloys"" are developed recently for compressor or turbine disks of gas turbine engines in High Temperature Materials 21 Project at National Institute for Materials Science (NIMS) in Japan. These Ni-Co base superalloys combine the characters of two kinds of y- y' two-phase alloys (Ni-base and Co-18at%Ti alloys) and have higher tensile strength and creep resistance than C&W UNDIMET 720Li superalloy."

Jan 1, 2006

By M. B. Mansur, A. S. Guimarães, A. J. M. Santanilla, D. C. R. Espinosa, J. A. S. Tenório, R. A. Pini

The separation of Ni and Co from sulphate medium containing Mn, Mg, Cu and Ca was carried out by solvent extraction. The object of this study was to investigate the synergistic effect using phosphinic acid (Cyanex 272) and carboxylic acid (Versatic 10) and their mixtures in kerosene. The extraction percent of each metal ion was found to increase with increasing pH and extractant concentration. Co was preferentially extracted over Ni under the same extraction conditions. The separation factors of Ni/Co increased with the use of the synergistic systems investigated.

Jan 1, 2014

By Mark Sherman, M. Dennis, Raj Rajamani

"The two Alumbrera 36ft (10.97m)dia. SAG mills were sized, using the FDW ""Grindpower 'I program, to treat an average of 1852 tph each. This paper describes how modelling of the shell lifter design, using the Millsoft program, identified milling inefficiencies caused by poor charge motion. This explained the ""as built"" circuit's inability to achieve the throughput rates predcted by the circuit's designer. Use of the Millsoft program to design a new, dramatically different lifter configuration, in conjunction with a different approach to variable speed drive utilization, has resulted in an improved charge motion and a 30% increase in hard ore milling rates. The new lifter design has allowed the designer's predicted average throughput rates to be achieved.IntroductionThe Alumbrera project grinding circuit consists of two 36ft dia. X 17ft EGL, 13 500 kW, variable speed, gearless drive SAG mills coupled to four 20ft dia. X 30ft EGL, 6 000 kW fixed speed, gear driven, ball mills. The circuit is configured as two identical grinding aisles, each consisting of one SAG mill and two ball mills. No pebble crushing circuit was installed due to the expected absence of a critical size fraction in the first years of production. However, the grinding circuit layout does incorporate space for a pebble crushing retrofit. At present, only about 5% - 10% of the new mill feed reports as trommel oversize and is recycled back to each SAG mill using a water cannon.The circuit was designed to be ball mill limited and to treat the four major Alumbrera ore types at rates varying between 68 000 tpd, and 89 750 tpd, depending on ore hardness. Average throughput rate, and hence nominal design rate, for the grinding circuit was 80 000 tpd (1 852tph per line at 90% availability)."

Jan 1, 1999

By C. A. Sosa-Blanco

Minera Sabinas in central Mexico treats a complex sulfide ore containing galena, chalcopyrite, sphalerite and argentite as valuable minerals, and in some cases important amounts of non-magnetic pyrrhotite. For high pyrrhotite ores, results obtained by selective flotation showed good grades and recoveries in the lead-copper circuit, but a commercial zinc concentrate could not be produced due to the high floatability of pyrrhotite. When this is the case, an alternative method was proposed to produce a bulk concentrate by flotation which is then leached to recover copper and zinc from liquor in a SX-EW circuit. Leaching was conducted in an autoclave in order to study the effect of temperature and pressure, but bioleaching tests were also conducted. Leaching lead-silver residues were treated by cyanidation in order to recover silver values. The results obtained by selective flotation and by bulk flotation with leaching of the bulk concentrate showed that the latter alternative increased zinc recovery by 30 % with similar recoveries of the other metals.

Jan 1, 2007

By M. A. Cristovici

"In the last few years CANMET has taken the initiative by investigating the possibility of reactivating abandoned old tailings dumps (for gold production) which would be of potential economic interest across Canada.Nova Scotia was one location where numerous gold processing plants were in operation in the early days. A survey of the old tailing dumps was conducted and some areas of interest were selected. Among them were the sites identified as Lake Charlotte and Forest Hill.Ore samples collected from those tailing ponds were examined for their chemico-mineralogical composition and investigated for gold extraction. Three technological concepts were tested: flotation, direct cyanidation and flotation followed by cyanidation of the flotation concentrate. The combined flotation- cyanidation variant, yielding a gold recovery in the range of 90%, was recommended for processing the tailing ore.Pilot-plant runs carried out by a commercial testing firm (data not included in this paper) confirmed the conditions and results of CANMET's technology.As a result a consulting-engineering firm designed the processing plant which is expected to begin operation in the near future.IntroductionIn the last few years CANMET initiated a research program to locate in Canada, abandoned gold-silver tailing dumps of potential economic interest and to explore the possibility of recovering the precious metals from these old deposits by modern techniques.A literature search revealed that the first production of gold in Canada was recorded in British Columbia in 1858 and that, production prior to 1900 was essentially restricted to the Yukon, British Columbia Nova Scotia and Quebec. During the early 1900s, Ontario, Manitoba and the North West Territories joined the ranks of the gold producers.Early milling and recovery methods were mainly restricted to sluice boxes, gravity stamps and amalgamation. Froth flotation and cyanidation were introduced at about the turn of the century.Recovery of gold at plants using flotation and cyanidation was very good, therefore the tailing ponds resulting from those operations would, very likely be of little or no economic importance. However, the gold recovery at the amalgamation and gravity concentration plants appeared to be lower, indicating the possibility that significant amounts of recoverable gold would have been carried with the tailings to the dump sites."

Jan 1, 1986

By J. C. Rudolph

"THE TOPIC on which I am speaking this afternoon is ""The Future of the Canadian Oil Industry.'' At the time of C + 100, we should take a searching look at ourselves, an honest appraisal of our achievements and a forthright accounting of our shortcomings as well as the uniquely Canadian aspects of this industry. I would like to put before you some of my views on the direction we are taking in the exploration field and in the production field. I would also like to speak briefly on some of our problems and the role of the various segments of our industry in solving these problems.First of all, let us look at the exploration picture. We are in the midst of an exploration boom. There were 133 seismic crews active in Western Canada this winter, the highest since 1957, land prices are appreciating rapidly, Canadian oil reserves increased + 16 per cent during 1966, there is a great demand for technical personnel of every kind and the whole industry, except the drilling segment, seems to be prospering. This surge of activity has its roots in two major occurrences. The first of these was the change in the pro-ration system in Alberta, the major producing province, accompanied by the change in spacing pat-terns. The proration change was designed primarily to encourage in-creased exploration and it has certainly had this effect. It has also had the unforeseen effect of put-ting everyone into what we, in the oil business, call ""elephant hunting."" In other words, the days of the development of barely economic, marginal fields are over. Oil companies today are only interested in high-reserve, high-productivity, high-quality reservoirs."

Jan 1, 1968

By A. Djebara

Today, indoor air quality, especially in manufacturing industries, is of great interest due to the use of new processes and advanced materials such as those containing nanoparticles. Manufacturing processes generate aerosols (dry or wet) which can be detrimental to occupational health and safety and to the environment. Controlling metallic particle emissions during machining processes should limit their formation at the source, and thus minimize the risk of exposure; this at-source reduction requires the characterization of the particle emitted (size, nature, concentration, etc). The metrics normally used in characterizing fine and ultrafine particles include the mass concentration, the specific surface and the number concentration. Most of these metrics are affected by the size, the geometry and the density of the measured particles. Information about the form and the real size of the particles is thus very important. A procedure for collecting and characterizing fine and ultrafine metallic particles was developed and applied to the study of particles emission during the machining of aluminum alloys. It was found that metallic particles emitted during the machining of aluminum alloys are of various shapes and sizes, and this information must be taken into account when characterizing these particles.

Jan 1, 2011

By C. R. Ross

"The purpose of this paper is to review the activities of international organizations concerned with the problem of dust hazards in mines and to indicate the extent of Canadian participation in these activities. The work of the International Labour Office in sponsoring conferences and reports on the appraisal and control of dust hazards and in the development of standard radio-logical classifications is considered in some detail. Also discussed are the role of technical societies, such as the American Conference of Government Industrial Hygienists, in the development of proposed standards for dust exposure and the functions of international committees concerned with particular hazards, such as the U.I.C.C. (Inter-national Union Against Cancer) Committee on Asbestos and Cancer."

Jan 1, 1969

By Keith Spence

"The notion of ""value"" has always been a subjective and contentious issue. Indeed, Value is in the eye of the beholder. There are varied methods and practices for valuing property, as there are industries in which they are applied. For example, there are ""replacement value"", ""insurance value, ""salvage value"", ""appraised value"", ""book value"" and ""fair market value"", to name a few, although in the mining industry, valuations usually refer to fair market value.In the Canadian mining industry, at present, there are no comprehensive regulations or guidelines that specify which approaches or methods are appropriate for use in the valuation of mineral projects. In January 1999, The Mining Standards Task Force of the Toronto Stock Exchange and the Ontario Securities Commission recommended that the Canadian Institute of Mining, Metallurgy and Petroleum establish a committee to review and advise on approaches and methodologies for the valuation of mineral properties. Among the approaches to be considered, are included the following: the Discounted Cash Flow Approach, the Cost Approach, the Option Pricing Approach and Market Comparables Approach. In addition, methodologies differ depending on whether the project is at the exploration stage or the producing stage.The CIMVal committee expects that its final report will form the basis for a standard Canadian Code for the valuation of mineral properties."

Jan 1, 2003

By Andrukaitis. E.

The increasing use of electronic equipment by the Canadian Forces has increased the importance of electric power. A power source that is packed with energy and yet light, small and durable is the common request of military users. However, this needs to be achieved while also addressing the requirements of safety, reliability and low temperature performance. The potential use of fuel cells in a military environment has become a possibility in several areas in the 21st century. Some examples of power source requirements and the materials related R&D required to give better, higher energy power systems in the future will be discussed.

Jan 1, 2005

By K. J. G Hedges

"Once a health based guidance limits for exposure to diesel exhaust have been established, and as part of a multi-disciplinary team, the program for exposure reduction should incorporate the plan-do-check-adjust cycle. Setting a suitably protective (health based) occupational exposure limit (OEL) for diesel particulate matter (DPM) and nitrogen dioxide is a key driver to reduce exposure. It is important to go beyond regulations and reduce exposure to diesel exhaust, DPM, as low as reasonably achievable (ALARA) such as that prescribed under the Australia, Queensland Mining and Quarrying Safety and Health Regulation 2017 where under section 135 Limiting workers exposure, the workers exposure must not exceed the exposure limit applying to the worker for the hazard; and is ALARA. It appears that previously acceptable OELs are no longer safe. Therefore it is important that the internal responsibility system be implemented and the precautionary principle approach be followed, especially as it may be some time before a suitably protective OEL specifically for DPM is in place. One leading multi-national mining company BHP Billiton has acknowledged a significant lag that exists between regulatory action and the level of science that informs health risk. This company is managing exposure to diesel exhaust to as low as technically feasible. This same company that has set an interim target for managing diesel exhaust to 0.03 mg/m3 is achieving these levels which paves the way for other mining companies and general industry including construction. The Occupational Cancer Research Centre 2017 recommends reducing personal exposure to within 0.02 mg/m3 (EC) for underground mining and 0.005 mg/m3 for other workplaces. Controlling DPM is important to prevent cancer however it is also important that that nitrogen dioxide (NO2) be reduced (ALARA) and that careful selection of control technology be considered such as the proper selection of a diesel oxidation catalyst so that the level of NO2 does not in fact increase. The example from BHP Billiton provides a leading practice including using a multi-disciplinary approach and the importance of controlling emission at source and having an auditable diesel emissions based monitoring program in place."

Jan 1, 2019

By C. Holmes, T. Holmes

Engineered-in material handling problems are responsible for significant unrealized value in mineral processing plants. At the root, is a lack of awareness and understanding of bulk material handling science and how important it is, especially in early design stages. Mineral processes add value to mined raw feedstock through physical and chemical transformations in unit operations, but only if the material can flow through them. Essentially, each unit operation receives a unique feedstock and produces a unique product to be collected, transported, and fed into the next unit operation. Such material-handling systems can only be expected to achieve design throughput if the system equipment is designed to the materials’ characteristics, over their full range of conditions. This requires quantification of flow properties to support the necessary customized equipment designs. Too often, assumptions or “library values” of a material’s properties are used as the basis for flow modelling and conceptual, and sometimes even detailed, design. This is especially true for hazardous materials like uranium ore, for which the additional precautions, costs, and time necessary for safe handling are often used to rationalize postponing or even bypassing testing. The surprises that often transpire in the wake of insufficient material handling consideration can have acute and costly effects. Fortunately, there is a better way.

Jan 1, 2020

By M. Abumiya, N. Onodera

Stabilization of arsenic via the precipitation of large-sized scorodite (FeAsO4·2H2O) particles usually involves the use of expensive autoclave systems operated under high temperature and pressure conditions. Alternatively, DOWA developed a novel scorodite synthesis process (DMSP®) wherein the Fe(II) ions in solution containing As(V) ions were oxidized by O2 gas under atmospheric pressure. In this process, crystalline scorodite particles were formed via the formation of a gel-like precursor containing Fe(II). Based on this concept, in this study, we have demonstrated the synthesis of scorodite particles by the addition of Fe(III)-containing solution to the experimental solution containing Fe(II) and As(V) ions, without the O2 gas oxidation process. Ferric sulfate (Fe2(SO4)3) was used as the source of Fe(III) ions. Results indicate the precipitation of scorodite particles, comparable to that of the O2 gas oxidation method.

Jan 1, 2014

By Rita Aiello, Stan Mack, Peter Werth, Joseph McCarney, Jozef Stachulak

"Johnson Matthey has developed the first diesel particulate filter (DPF) for underground mining that controls particulate matter (PM) at the same time as maintaining emissions of NO2 at or below engine baseline levels. DPF technology is critical for controlling PM which is classified as a carcinogen, but passively regenerating systems rely on the use of oxidation catalysts that can potentially increase NO2 emissions. This paper reviews the development of low-NO2 PM control technology and the results from testing this technology underground on diesel mining equipment. KEYWORDS Decomposition catalyst, Diesel particulate filter (DPF), Diesel particulate matter, Mining Continuously Regenerating Trap (CRT®), NO2, SCR INTRODUCTION The introduction of diesel particulate filter (DPF) technology on heavy duty diesel (HDD) engines has been an important step towards addressing the clean air and health concerns for mining companies. Control of diesel particulate matter (PM) emitted from diesel engines is already being implemented for on- and off-road vehicles, and similar legislation is being prepared for mining equipment. In addition to PM, the diesel emission control strategies (DECS) also reduce carbon monoxide (CO) and hydrocarbons (HC). Some DECS control oxides of nitrogen, or NOx, which is composed of NO and NO2. Johnson Matthey has led the development of emission control technologies for diesel engines for almost 30 years. Over the last ten years alone JM has supplied over 3 million Continuously Regenerating Trap (CRT®) DPF systems for on-road vehicles, and over 200,000 systems for off-road vehicles. The patented CRT technology combines a diesel oxidation catalyst (DOC) with a DPF to effectively trap harmful PM from diesel exhaust, while removing CO and HC. The DOC converts part of the engine NOx to NO2, which reacts with the trapped soot to regenerate the filter. As engines become more fuel efficient, less waste heat enters the exhaust. This can be a disadvantage for after-treatment systems as it leads to lower catalyst operating temperatures. The CRT system regenerates passively, without addition of heat, at temperatures that are typical of diesel engine exhaust. JM recently launched the Mining CRT system which integrates CRT technology with NO2 abatement to reduce PM and tailpipe NO2 from underground diesel mining equipment. This is the first technology proven to control both PM and NO2 emissions for a cleaner, healthier working environment. The Mining CRT is also cost-effective compared to other technologies."

Jan 1, 2019

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

By R. R. Bassermann

THE property of Howey Gold Mines, Limited is situated at Red Lake, Ontario, one hundred and seventy-five miles east of Winnipeg and eighty miles north of the Canadian National Railway line. The mine has been a continuous producer since April, 1930, and at present is hoisting 1,350 tons of ore per day. The shaft consists of three compartments (see Figure 1, sketch B). Hoisting is done by two skips in balance, one of which is interchangeable with a cage. Sinking had been carried out at three different periods. From the surface to the 550-foot level, the sets had been spaced at seven-foot intervals, from the 550-to the 1,060-foot level at six feet, and from the 1,060-to the 1,500-foot level at five feet. During the five years of operation, the shaft had become so badly worn, due to spill from the tipples and, to a certain extent, from the loading pockets, that re-timbering was considered necessary. It should be explained that no crushing is done underground because of the ad verse effect this would have on the efficiency of the sorting. The grizzly rail clearance above the ore pockets is fourteen inches and consequently the ore hoisted is extremely coarse. More than average spill from the loading pockets and tipples under such conditions is inevitable, and it is debatable whether underground crushing with consequent increased sorting costs would not be justified. The cost of complete re-timbering according to standard practice would have been prohibitive both directly and indirectly: A lengthy shut-down of the shaft, with the consequent disorganization of the staff and workmen, could not be considered. Accordingly, it became necessary to devise some method of repair that could be carried to completion in a very limited period of time. The shaft timber for the first 250 feet was not in need of repair. From the 250-foot to the 1,060-foot level the wall plates, posts, and blocking were in good condition. These had been protected by a one-inch plank lining put in at various periods during the past three years without interfering with hoisting operations. The end plates and dividers, however, could not be protected in this manner because of the lack of skip clearance. It was decided that, if the dividers in this section could be replaced, the shaft would be as satisfactory as if completely re-timbered. Several factors had to be taken into consideration in deciding on a suit-able method of repair. In the first place, the tipple plates had to be re-designed. To complete the job in a reasonable time, not only had work to be done on the tipple, but simultaneously from several points in the shaft itself. Since all power cables, pipe lines, etc., were in the manway compartment of the shaft, this compartment had to be left undisturbed.

Jan 1, 1935

By M. Pearson, L. Zunti

Pressure vessels in hydrometallurgy and many chemical process industries throughout the world require the use of specific lining systems to protect the parent vessel materials from corrosion and/or abrasion. Typically, these lining systems are required for processes that are corrosive and operate at elevated temperatures. Two basic lining system types arc: 1) refractory linings in conjunction with an impervious corrosion resistant membrane, and 2) metal-clad vessels consisting of titanium or other corrosion resistant metal bonded to a carbon steel shell. Operating conditions play a key role in selecting the type of lining system to be utilized for a specific application. Lining systems in turn have an impact on the process vessel size, which ultimately affects the capital cost of the vessel. The capital costs for each type of lining system must be considered for each application, as well as maintenance concerns, quality control, and delivery. It is clear that operating conditions play a key role in the final selection of lining systems utilized for specific projects based on initial capital cost, life-cycle maintenance costs, and overall service life. This paper will examine the fundamentals of each lining system, their inherent technical strengths and weaknesses, and present relative cost comparisons for each lining system as they apply to specific operating conditions and vessel sizes.

Jan 1, 2004

By George J. Simandl, Donald F. Gunning

At the beginning of the 20 century, British Columbia produced a wide variety of quality dimension stone products for both domestic and foreign markets. The industry flourished until the 1930s when most of the producing quarries closed as a result of the Depression. During the 1990s, British Columbia experienced the resurgent North American dimensional stone production trend. The industry benefited from increased prospecting activity and from substantial new investment in processing equipment, particularly in the granite sector. These activities resulted in new quarry developments, the reopening of abandoned quarries such as on Granite and Fox Islands <www.quadrastone.com>, and a renaissance in downstream value-added activities. British Columbia has reestablished itself as an important, reliable and innovative source of high-quality stone products.

Jan 1, 2001