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By P. Klossek

It is estimated that China accounts for 94% of the world supply of rare earths (Roskill, 2011). This fact, together with the impact of China?s export policy, poses a substantial risk to the security of the rare earth supply as well as a rare earth price risk. This situation has motivated an increase in the number of rare earth projects under development, i.e., there are currently more than 440 worldwide (Technology Metals Research, 2012). However, economically and environmentally acceptable processing technology to produce tradable products from rare earths (e.g., separated rare earth oxides) is not freely available on the market at the moment. In this respect, a lot of research and development has been initiated on this topic, in academia as well as in industry. Using a proprietary model and scenario-based analysis, we studied the impact that the development of rare earth processing technologies would have on the rare earth market and the economic feasibility of rare earth projects mentioned before. The analysis showed that this impact varies depending on the technology type (e.g., technology can affect project production volume, cost structure or both) and the legal context of the invention (e.g., free or limited by patenting availability of a new technology). The effect of a technology which influences project production volume is not the same as of a technology which changes project cost structure. The impact of a patented processing technology differs from the impact of a processing technology which is freely available on the market. In the case of a new technology which is limited by patenting, its impact depends on the market position (?producing?, ?next-coming?, or ?not producing? project) of the patent holder. The paper contributes to existing research by studying the dependence of the expected micro- and macroeconomic impact of rare earth processing technology developments on the properties of a new technology (e.g., costs, legal framework etc.). By this means, the paper adds to existing knowledge and attempts to make the rare earths market more transparent and predictable from a perspective outside China.

Aug 1, 2013

By N. Waters

"Nickel saprolite ores are normally mined as feed to Fe-Ni smelters or Ni matte smelting operations. The smelting processes typically require high Ni cut-off grades of approximately 1.5 to 2.2% Ni, depending on the operation. These very high cut-off grades result in a significant portion of the saprolite profile being regarded as “waste” and hence having little to no value. The Starved Acid Leach Technology (SALT) was developed to recover nickel and cobalt from nickel saprolites and Caron plant residues. Relatively small amounts of acid are applied to ground saprolites or Caron residues in order to selectively leach nickel and cobalt. The leaching is performed atmospherically under low free acid conditions. Nickel and cobalt may be recovered from the leachate as a mixed hydroxide. The mixed hydroxide may be added directly to a saprolite smelting operation or refined separately. InCoR Technologies is advancing the application of SALT at a number of sites. Bench scale testing has provided a relationship between acid addition and nickel extraction in leaching. Conceptual engineering studies have been completed by SNC Lavalin. The simplicity of the SALT technology provides the benefits of low capital and operating cost and an expected rapid ramp up to full production.INTRODUCTION The recent history of hydrometallurgical nickel laterite treatment plants has demonstrated mixed financial and operational performance. Table 1 summarizes the next generation plants built after the financial and/or technical failure of the Bulong, Cawse and Murrin-Murrin plants in Australia. The Coral Bay plants (Line 1 and 2) stand out (and now Taganito) as relatively low capital cost, simple (no acid plant, production of mixed sulfide product), and modest in scale (10, 12 and 36 kt Ni/a). However, the other plants in the list (Ravensthorpe, Ramu, Goro and Ambatovy) are all characterized by financial and technical challenges. All plants have a very high capital cost ($67,000 to $120,000 USD/annual t of Ni production). Ravensthorpe was sold by BHP Billiton after a poor startup. Ramu has had a steady ramp up but only produces mixed hydroxide for refining by others. Goro has had an extended construction period (since 2001), is high cost and has been very slow to ramp up to design production rates. Ambatovy has had a steady ramp up."

Jan 1, 2017

By D. Tetsuka, H. Okamoto

The amount of impurities to be processed in a copper smelting process has increased for recent years because of an increase in the electronic scrap amount. It has been found that Sb and Ni effect on the operation of our copper electrorefining process. It is found that the current efficiency of the copper electrorefining tended to be decreased as the Ni concentration in the electrolyte increased. The passivation of the process seemed to be more related to SO4 concentration in the electrolyte rather than the Ni concentration in it. The current efficiency decreased when the Sb content in the anode was high. A high Sb content in the anode caused easy passivation by forming a gel-like film in the slime layer. We have developed a method to for see the anode passivation in a short time while generating a slime layer. We confirmed the tendency of passivation through the experiment of changing Pb content in anode. Passivation was easily occur with an increase in Pb content in the anode. The amount of slime increased as the Pb content in the anode increased. This suggests that passivation was facilitated because liquid diffusion near the anode was inhibited. INTRODUCTION The amount of impurities to be processed in copper smelting has been growing in recent years because the amount of electronic scrap has increased. Figure 1 shows that the contents of Sb and Ni in copper anodes have increased since 2007.High Sb and Ni contents in the copper anode decreased the current efficiency of the process and made the quality of copper cathode poor because of the anode passivation and the formation of floating slime in the electrolyte during electrorefining. If these influences of impurities are suppressed, it would be possible to make copper electro-refining current density higher and to process much amount of electronic scrap. We examined the components of our copper electro-refining process like anode composition, slime properties and electrolyte composition, and investigated the mechanism by which Sb and Ni affect passivation and current efficiency. When examining the influence of Ni, we noticed that the SO4 important. The effect of SO42 – was also discussed

Jan 1, 2019

By R Zavadil, S Kuyucak, F Fazeli

Proton exchange membrane (PEM) fuel cells generate electricity by reacting hydrogen and oxygen. A thin, bipolar electrode material provides a medium for electron exchange with the electrolyte, alternately serving as anode at the hydrogen-rich side and cathode at the oxygen-rich side. Stainless steels have sufficient corrosion resistance to qualify as bipolar plate materials. However, the protective chromite layer increases the contact resistance, the battery’s internal resistance; and thus, decreases the electrical efficiency of the fuel cell. A heat-treatment is proposed and investigated via simulation by ThermoCalc / Dictra and experimentally, to generate a sufficient quantity of conducting surface carbides that breach the protective layer. Once carbide growth is arrested, a subsequent heat-treatment is also needed at a higher temperature to restore the corrosion resistance by filling-in the Cr-depleted layer (sensitization) around the carbide particles.

Jan 1, 2014

By C. G. Anderson

As the global demand for copper and gold steadily increases and the need for environmentally sound processing also grows, successful hydrometallurgical treatment of enargite (Cu3AsS4) concentrates has come to the forefront. This type of concentrate contains considerable arsenic so that successful arsenic fixation, for example as scorodite, is of the essence. This paper outlines the successful application of low temperature and low pressure nitrogen species catalyzed (NSC) hydrometallurgical pressure oxidation of enargite concentrates. The successful stabilization of the arsenic as an iron arsenate compound is discussed. Also, the use of experimental design software is highlighted as a process application and optimization tool.

Jan 1, 2006

By M. S. Badollet

Introduction The manufacture of some asbestos products involves the use of asbestos in combination with water, cement and granular fillers. This type of production is often called the wet or semi-wet process and requires the use of either pressure or vacuum to eliminate the excess water in the fibrous blend so that the product may develop the proper strength during the curing stage. Asbestos - cement products available today are numerous and are a valuable contribution to the building industry. Their production in quantity depends upon the type of equipment employed, the speed at which it can be operated, and the factors involving the? blending of asbestos, cement, water, and fillers. Assuming that all mechanical troubles at a plant have been eliminated or are under control it is still advisable to study the basic properties of the raw materials used in the asbestos-cement products. The type of cement used is an important factor, but usually the manufacturer of the cement is willing to work with the asbestos development engineer and recommend the proper type to be used for the product. The source of the water should not be overlooked as a general factor involved in the production cycle. Waters containing a high percentage of contamination such as silts, humus, or soluble salts may adversely affect the setting of the cement or cause a slowing down of the production rate in the factory. Asbestos in combination with cement is an ideal material fo1 building products. It is inorganic, will not deteriorate, and can be handled by mechanical equipment with a minimum reduction of fibre length. The many physical properties peculiar to asbestos fibres should be well understood by the manufacturer. They may be briefly enumerated as follows: fibre strength, fibre composition, sliminess, length, harshness, softness, and filterability or porosity. This last named property is important and it is the purpose of this paper to present some basic studies on filtration as applied to production problems.

Jan 1, 1949

By R. A. Campbell

Pig iron and silicospiegeleisen were produced experimentally from a very low-grade manganiferous iron ore from Steep Rock, Ontario, by a two-stage electric smelting process. The most favourruble operating conditions were determined for each stage. Cement clinker then was made by calcining the slag from the second stage of smelting, with additional limestone and alumina. (This slag would normally be a waste material). The cement clinker produced had the composition of commercial Portland cement, and met the physical test requirements of the Canadian Standards Association Specification A5-1951 for normal Portland cement as well as could be expected for a material produced on .such a small scale.

Jan 1, 1958

By Hiroyuki Sano, Hiroshi Chida, Katsuya Toda, Takafumi Sasaki

Saganoseki Smelter & Refinery is one of the largest copper producers in Japan to produce 450,000 tons of new copper annually. Saganoseki used to operate six PS converters with "4 Hot-2 Blow" scheme, but managed to change its operation to "3 Hot-2 Blow" scheme with four PS converters, while maintaining the same production capacity. To achieve the operational change, the following improvements have been carried out; 1) Extending service life from 220 to 350 batches, 2) Shortening cycle time by increasing the blowing rate and the matte grade, 3) Reducing environmental impact by applying sophisticated fugitive gas collection system and 4) Saving energy by waste heat boiler’s modifications. The operational change has been successfully executed, and results in drastic productivity increase and cost reduction. Currently, Saganoseki is maintaining the efficient and consistent operation with 4 PS converters. This paper describes the above-mentioned improvements for increasing productivity and the recent operational conditions of the PS converters.

Jan 1, 2015

By Muhammad Tawalbeh

The calculated temperature history of a single particle of MgCl2 hydrates when it came in contact with fused salt electrolyte at 650 °C was determined using the measured heat transfer coefficient for the molten salt bath at 650 °C. The calculations revealed that the entire interior of the particle reached the temperature required for the formation of MgOHCI from hydrated MgCl2 in less than 2 seconds. This was much less than the time required for dissolution of the prills as observed in experiments. It is very likely that the formation of MgOHCI during prill dehydration and dissolution is a result of hydrolysis in the interior of the prills.

Jan 1, 2004

By A. Musschoot

"The paper will review general types and designs of vibratory feeders, describing briefly the design features and characteristics that apply to the application of specific types. Control considerations for selecting types will be dis• cussed, such as fixed or adjustable, manual or automatic, individual or multiple bank, and process requirements. Design parameters for hopper openings and installation geometry will be discussed, including consideration of material size distribution, segregation, moisture content and other characteristics, based on practical applications and experience as well as theory. Pan designs and the selection of pan materials will also be discussed with reference to wear, corrosion, impact and practical economic factors."

Jan 1, 1972

By A. E. Cameron

The theory of atomic distribution of the stranger atoms in the space lattice of the solvent metal has been well developed by Rosenhain. It has long been known that the addition of one metal to another to form a solid solution increases the strength and hardness of the solvent metal. This increase is practically proportional to the amount of added substance up to the limit of solid solubility. To account for this increase in hardness and strength, Rosenhain assumes that the stranger atoms occupy positions on the solvent metal space lattice. Atomic attractions about the stranger atoms will not be the same as in the case of the pure metal, and there will thus be a disturbance of the orderly arrangement of the atoms on the space lattice, or a distortion of the lattice. Such a disturbance would interfere with the ease of slip along the planes and would thus tend to promote strength and hardness. Rosenhain notes that not only may there be a local disturbance of the lattice about the stranger atom but there may well be also a measurable change in the dimensions of the lattice as a whole. The relative amounts of local and general distortion of the lattice will depend upon the nature of the lattice itself. As Rosenhain says, "If the lattice is comparatively soft and flexible the distortion is likely to be largely local. In a stiff lattice, however, local distortion will be resisted and there will be a correspondingly increased general distortion."

Jan 1, 1927

By C E. Gordon Brown

Aircraft utilization, weather and cost data are given for three separate projects north of the sixtieth parallel in the Northwest Territories and the Yukon Territory. These operations, carried out by helicopter-equipped geological and prospecting parties, have cost $24 to $30 per square mile, depending principally on the distance from the base. They provide adequate surface exploration of areas with 40 to 50 per cent rock outcrop. A good one-inch-to-one-mile geological map can be made. T HE exploration of the Canadian northland has been given increasing attention by the mining industry during recent years. In many cases, the initial problem is to make an adequate reconnaissance of a large area where existing geological information is meagre. The Geological Survey of Canada pioneered the use of helicopter-equipped geological parties for mapping at a scale of eight miles to the inch.

Jan 1, 1964

By J. K. Shaw

The science of low temperature engineering is well entrenched in mining. Uses for common cryogens, including liquid oxygen (LOX), liquid nitrogen (LN2), and liquefied natural gas (LNG) in the gas and minerals industries are reviewed. Potential future applications are discussed within the scope of mining, particularly in refrigeration and ventilation. The second part of this paper focuses on the Linde cycle, which is at the heart of most liquefaction plants. Steady state equations describing the mass and energy flows are presented. The paper concludes by explaining the concept of a wind powered Linde- Hampson cryogenic cycle and assessing, with scoping calculations, the technological feasibility of producing cryogens with an intermittent source of (renewable) energy.

Aug 1, 2013

By J. P. Thomson

Magnesium alloys are steadily improving their market share as structural components especially in the transportation sector. Therefore, there is a great deal of interest from the automotive and the metal casting industry to develop viable economic casting processes for magnesium-base alloys. This paper summarizes the preliminary results on the continuing projects within CANMET-MTL on casting processes such as gravity and low-pressure casting in sand molds, permanent molds and lost foam.

Jan 1, 2004

By M. Sengupta

International trade in minerals plays a very important role in the economic growth of many nations. Several less developed countries a1•e heavily dependent on their mineral exports for earning foreign exchange, which is needed for industrialization. Mineral exporting nations experience many problems in international mineral markets; the most important are tariff barriers, deteriorating terms of trade, instability in metal prices, etc. The formation of international mineral cartels to raise prices can be successful only to a limited extent and only for a short period of time.

Jan 1, 1976

By D. J. MacKinnon

"The Canadian Copper Company, formed in 1885, began mining the nickel-copper ores of Sudbury in 1887 and producing nickel-copper matte from its smelter in 1888(1). Although it was quickly appreciated that the separation of nickel and copper (i.e. refining) was critical to the production of a marketable nickel product, refined nickel was not produced in Canada until about 1918. From the beginning of the industry, there was considerable political agitation to refine nickel in the Province of Ontario(2). The companies, however, claimed that the existing processes, viz. the sodium sulphide ""tops and bottoms"" process operated by the Orford Copper Company of New Jersey, U.S.A.(1,3,4) and the carbonyl process(5,6) developed by the Mond Company at Clydach, Wales, were too costly to operate in Canada. Nickel was first refined in Ontario about 1918 when the International Nickel Company opened a nickel refinery at Port Colborne, Ontario(6). Initially, however, the refinery at Port Colborne employed the Orford sodium sulphide process, and the first electrorefined nickel in Canada was produced in 1920 by the British America Nickel Corporation whose mine and smelter were located in Sudbury, Ontario, but whose electrorefinery was located at Deschenes, Quebec, near Ottawa, Ontario. The purpose of this article is to outline the early history of nickel electrorefining and to trace the significant developments which led to the first successful commercial electrolytic nickel refinery in Canada. The development of an electrolytic process for refining nickel is due largely to the efforts of four individuals, viz. Carl Hoepfner, Hans A. Frasch, D.H. Browne and ultimately N.V. Hybinette, and the contribution of each is discussed separately below."

Jan 1, 1999

By M. Muinonen, R. Pandher

Royal Nickel Corporation is developing the Dumont Nickel Project, a large nickel sulphide deposit located near the town of Amos, Québec. The nickel occurs as pentlandite, heazlewoodite, and awaruite. The relatively low grade ore can be processed to a very high grade nickel concentrate, containing 29% Ni. The absence of copper and precious metals in the ore renders this concentrate amenable to processing by dead roasting in a fluid-bed roaster and smelting in an electric furnace to produce ferronickel for sale to stainless steel producers. Laboratory test work and conceptual engineering design was completed to demonstrate the amenability of Dumont concentrate to produce ferro-nickel.

Jan 1, 2015

"Real-time, on-stream analysis of the metal content of process slurries is an essential prerequisite for process monitoring and advanced control of mineral processing circuits. On-stream X-Ray Fluorescence (XRF) sensors for base metal applications are available commercially and form the basis of many plant monitoring circuits. To date, these commercial technologies have been insufficiently sensitive to measure precious metals such as gold and platinum group elements, typically present at part-per-million (ppm) and sub ppm levels. CSIRO has developed a novel X-ray based technology, called UltraGold, which enables detection of gold in slurries on a real-time basis with a precision below 100 parts-per-billion. This technology is based on the use of advanced X-ray optics, extensive Monte Carlo computer modelling for analyser design, high accuracy X-ray spectrum fitting where the X-ray intensities are matrix corrected. In this paper, we will introduce this technology and discuss the results of a proof of principle study performed in the laboratory with plant slurries (tailings and concentrate) from an Australian beneficiation plant. Finally, we will discuss further planned improvements. As projected grades in (gold) mining around the world fall and several large-scale mines approach the limits of their economic reserves, this method can enable significantly reduced operating costs by rapid analysis to improve circuit efficiency and hence improve recovery significantly.INTRODUCTION This paper describes a study undertaken to explore the feasibility of applying CSIRO?s UltraGold XRF technology to the on-stream measurement of gold in process slurries. The provision of rapid, accurate information of gold grade in feed, tailings and concentrate streams would facilitate significantly improved process control and early detection of plant upsets, resulting in substantial cost-savings. CSIRO have patented X-ray fluorescence (XRF) techniques for the analysis of key elements in slurries present at part-per-million (ppm) and sub-ppm levels. Conventional, commercially available on-stream XRF instruments generally have detection limits in the tens of ppm range, precluding their use for analysis of elements like gold that are mined and processed at much lower concentrations."

Jan 1, 2017

By P. D. Barrette

This paper deals with the flow of granular materials in bins. A hybrid Lagrangian-Eulerian numerical model is introduced. The model is based on Particle-In-Cell (PIC) advection, and continuum equations describing a Mohr-Coulomb criterion. Experiments were conducted to test and verify the performance of the numerical model. Tests were done using three types of particles. Measurements of material properties and flow rates were carried out. Video records were also obtained and used to examine flow patterns. The results indicate that the numerical simulations produce deformation patterns and flow rates which are in good agreement with the experimental observations.

May 1, 2007

By J. C. White

This paper, after a brief introduction giving the history and geology of the area, deals with mining operations at the Copper Mountain mine of Gaspe Copper Mines, Limited. It discusses development operations, and then goes into the mining methods employed, covering drilling, grade control, blasting practice, loading and hauling, and the road and service machines used.

Jan 1, 1969