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By P. J. Finnis

This paper describes the use of wire rope on open-pit mining equipment, giving specifications and examples of the performance achieved. Installation methods are also discussed, making the paper of considerable practical use to mine operators.

Jan 1, 1973

By Fathi Habashi, Ahmet Deniz Bas

"The mechanism of leaching of semiconducting minerals such as PbS, ZnS, UO2, etc., has been the subject of intensive speculation by hydrometallurgy researchers in the early 1950s who assumed the formation of intermediate surface complexes that could be neither separated nor identified by physicochemical techniques. The electrochemical theory of leaching introduced in the late 1960s resolved this problem by comparing the leaching process to a corrosion phenomenon similar to the corrosion of metals. Few years later, experimental evidence showed that anodic and cathodic zones are formed on the dissolving mineral although no electric current is imposed on the mineral during dissolution. A discussion of these findings is outlined.INTRODUCTIONIn the early 1950s researchers realized that kinetic studies for leaching ores are as important as thermodynamic calculations. It was also during this period that the concept of species adsorption on mineral surfaces has dominated the interpretation of the mechanisms of most reactions. This may have been due to the fact that many researchers of this period came from the mineral dressing sector and were influenced by flotation theories. However, when the knowledge of lattice defects and the semiconductivity of minerals became known and their importance in extractive metallurgy was realized, there was a need to explain the leaching reactions in light of these modern theories (Habashi, 1969, 1970). Semiconducting minerals of importance in metallurgy are two categories: the sulfides such as those of copper, lead, zinc, and the oxides such as those of uranium."

Jan 1, 2016

By S. C. Livanou, S. P. Tampouris, E. N. Zevgolis

In ferronickel (Fe-Ni) production from oxidized nickeliferous ores, mechanical losses of ferronickel in the slag are reduced by magnetic separation. Slag from the electric furnaces (E/Fs) contains 0.16% Ni. Its magnetic separation gave a pre-concentrate with 0.76% Ni, weighing approximately 6.5% of the feed. Nickel recovery was 29.7%. This pre-concentrate was then treated in a second (concentration) plant. Concentration treatment involves screening, crushing and magnetic separation. A pre-concentrate with 0.76% Ni gave a magnetic concentrate with 2.58% Ni and a non¬magnetic part with 0.35% Ni. Smelting of the non-magnetic part without the addition of a reduction agent in a laboratory electric arc furnace, gave a ferronickel alloy with approximately 20% Ni and a slag with 0.16% Ni.

Jan 1, 2005

By M. A. Vos

"Aggregates are the low-cost mineral raw material of building construction. Large volumes of aggregate are consumed each year. The availability of aggregates in southern Ontario is discussed in the context of the geological formations in which they occur. Sand and gravel are abundant in glacial deposits and in recent sediments. A knowledge of the glacial history is important for their discovery. Bedrock formations provide a variety of aggregates in Ontario. Knowledge of the rock types involved and of the depth of overburden are important for evaluation of the aggregate potential of bedrock resources in an area. Utilization of available resources intensifies as the population increases. Urban development makes it progressively more difficult to satisfy the demands of the construction industry. The effects of urban development on the aggregate resource base of an area are illustrated by developments and consumption statistics in the Toronto- centred region. There is an obvious need for a comprehensive survey of available resources in urban areas to serve as a guide in land-use planning. To fill this need, staff members of the Industrial Minerals Section, Geological Branch, Ontario Department of Mines and Northern Affairs, are engaged in mapping projects and mineral resource studies in southern Ontario as well as in some urban areas of northern Ontario."

Jan 1, 1972

By J. Mirza, E. Nicol, J. Lipkowski

Gold passivation in thiosulfate leaching media is a major barrier to its implementation. Addition of Cu (II) into the leaching solution has shown to aid in gold dissolution, but the mechanism by which it acts, and its role in the passive layer, remains unknown. Surface Enhanced Raman Spectroscopy (SERS), in tandem with linear sweep voltammetry, were employed to determine the dependence of leaching currents on mass transport and for fingerprint identification of sulfur species on the surface of gold. SERS leaching experiments were performed using gold nanorod electrodes that showed increased stability compared to other SERS active surfaces.

Jan 1, 2011

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 Wei Wei

Mining induced ground movement and/or stress redistribution could cause ground instability issues. This is particularly true when the extraction of large stopes is done with one or two large production blasts. Often enough, it is the nearby mine development like haulage drifts and cross cuts that are influenced the most by production blasts. Proper and timely mitigation of ground control issues due to stress redistribution is required. This is usually done by drift rehabilitation involving the installation of secondary support system in the affected areas of the mine development which include; slashing, wire mesh, and in some cases the use of shotcrete liners. It is imperative that such rehabilitation be implemented to the mine infrastructure in a timely manner in order to avoid aggravated ground control problems and production delays. If the real time performance of the support system is captured, it would be possible to determine the timing for rehabilitation job. Birchtree Mine in Thompson, at the Vale Manitoba Operation, has begun mining the 84 Deep Orebody. One of the identified risks is the stability of the crusher room under mining induced stress redistribution. It is proposed to use the U-Cell technology to monitor the primary support system performance (rebar bolts and extension bolts) and monitor the real time performances of the bolt axial loads. The U-Cell technology is a 7-inch long, coupler load cell that is screwed onto the threaded portion of a rock bolt prior to installation. Rehabilitation in the vicinity of the crusher area where U-Cells are installed is recommended when the bolts have reached 70% of their yielding capacity. Catastrophic ground failure can be avoided by adding secondary support in a timely fashion. This paper presents a case study at Birchtree Mine in Thompson Manitoba, where the performance of primary ground support system is monitored and recorded during production.

Jun 1, 2012

By Robert B. Parsons

"Canada doesn't really have a tax system for mining - it has eleven separate tax systems! The consequent maze adds some undefinable margin of difficulty to making investment decisions in Canada. But, this 11U1Ze is not likely to be simplified. Solution: learn it and sell it! Intricate Network of Winding PathwaysWebster's New World Dictionary defines the word ""maze"" as follows: ""a confusing, intricate network of winding pathways; labyrinth ... a state of confusion or bewilderment"". Webster's does not go on to give an example of a maze, but the dictionary could easily have referred to the taxation of a Canadian mining operation. The uninitiated would almost certainly look upon such taxation as a maze of the most perplexing sort.Twenty years ago, Canada's tax system was really quite simple. It is true that Canadian mining profits were subject to three levels of taxation (federal income tax, provincial income tax, and provincial mining tax), but this didn't pose a problem. Prior to 1974, at least the provincial income tax systems were somewhat the same in terms of rules .and rates, and even the provincial mining tax systems resembled one another. Mining profits were subject to pretty much the same rules, no matter what province or territory hosted the mine. Those were the “good old days” one could even dare to generalize about tax rates without fear of being labelled an imbecile!"

Jan 1, 1994

By Brien A. Perry, Art Wiebert

"Many organizations which have implemented Total Quality Management (TQM) are finding that the process has either stalled or is not working so well as originally envisioned. This can be particularly evident in an engineering environment where the uniqueness of engineers and their particular culture has not been adequately considered. Winning the commitment of a highly educated group ojprojemnnJJ1s to the TQM concepts, which are often initially 5W2 as too simplistic poses special challenges.Successful TQM implementations are found among technical groups where employees have significant input into creating the new work culture, feel empowered to make changes and are well trained in teamwork. A coach who is knowledgeable in implementation problems can, when working closely with the technical teams, help them circumvent obstacles and guide them successfully through the difficult early phases. The remaining key ingredient for success is supportive management which leads the change and is both informed and appreciative of the accomplishment being made.This Paper is based on first-hand experience with common problems and results encountered in implementing TQM in an engineering environment. Described in the paper are ways of avoiding these problems through awareness of the unique nature of engineering groups, implementation planning, just-in-time training and coaching people in the TQM process. The paper concludes with a focus on the opportunities and results from a successful implementation. These opportunities and results include the benefits each engineer can realize through process thinking, empowerment and teamwork."

Jan 1, 1995

By A. Alfantazi, L. Choudhary

Gold leaching in thiosulfate solution has attracted widespread research interest through the last two decades primarily due to its perceived environmental benefits in comparison to the conventional gold cyanidation technique. However, the data on the corrosion and/or corrosion-induced failures of plant infrastructure materials in the solutions relevant to thiosulfate gold leaching are very limited. Accordingly, this study aims to characterize the electrochemical corrosion behavior of stainless steel 316L in the thiosulfate gold leaching solutions. Electrochemical corrosion response was investigated using potentiodynamic polarization and electrochemical impedance spectroscopy. The morphology of corroded specimens was analyzed using scanning electron microscopy.

Jan 1, 2014

By Z. Zhang, D. Bouchard, H. Blanchette, A. Lemieux

This paper describes quality control methodologies for the production of semisolid A356 aluminum slugs with the SEED process. A methodology based on destructive tests carried out with an apparatus measuring the force to slice the slugs is presented. The force measurements were correlated with the solid phase morphologies of the slugs and were validated against a non destructive methodology that consisted in monitoring the temperature evolution of crucibles to produce the slugs and the drained metal. Results from the destructive and non destructive methodologies are compared and discussed.

Jan 1, 2006

By K. C. Sole

In most copper solvent-extraction operations, an important consideration in choice of extractant is the requirement for high selectivity of copper over iron. Ester-modified aldoxime extractants presently offer the best Cu:Fe selectivity. In some plants, however, the process feed liquors contain significant amounts of manganese but little iron. Although manganese is not chemically extracted by oximes, trace amounts are carried over to the electrowinning circuit by physical entrainment. This may result in anodic oxidation of manganese which, in turn, can cause oxidative degradation of the organic phase when returned to the solvent-extraction circuit in the spent electrolyte. Many of these operations prefer to operate with higher levels of iron reporting to the advance electrolyte, as appropriate control of the Fe(II)/Fe(III) couple will ensure that manganese remains in the benign Mn(II) form. A new reagent, LS 4202, designed by Cytec, now offers the possibility of tailoring the iron co-extraction, so that appropriate Cu:Fe selectivity can be achieved in the solvent-extraction operation to maintain an electrolyte Fe:Mn mass ratio of >10:1, while retaining the other benefits offered by ester-modified aldoximes. The results of an integrated solvent extraction-electrowinning pilot-plant trial are presented, in which the performances of the conventional extractants ACORGA® M.5774 and LIX® 984N are compared with LS 4202. The Cu:Fe selectivity is demonstrated, along with results on the transfer of other impurities to the advance electrolyte.

Jan 1, 2007

By G. Guiglionda, A. Deschamps, F. De Geuser, M. Langille, B. J. Diak

"Increased demand for light-weighting in passenger vehicles has created a need for strong, light, ductile materials to be used in body-in-white applications. The AA6xxx-series of aluminum alloys are suitable candidates meeting most requirements but can fall short of the formability demands of designers, necessitating an understanding of what controls the formability in this alloy series. This work examines the effect of copper alloying in AA6xxx on the pre-ageing and natural ageing responses of the microstructure and mechanical properties. The changes in microstructure observed by differential scanning calorimetry and hardness testing are related to the work-hardening and strain-rate sensitivity parameters for these alloys measured by tensile testing. An observed asymmetry in the measured strain-rate sensitivity associated with increasing versus decreasing strain rate changes suggests that a different mechanism operates for the two conditions. It is postulated how this asymmetry in strain-rate sensitivity will impact the necking and ductility behaviour of these alloys.INTRODUCTION The widespread use of AA6xxx series alloys in the form of sheets has provided the need for a more thorough understanding of the complex interactions between composition, processing, resulting microstructure and ultimately, the mechanical properties of the alloys. Conventional industrial practices involve the production of rolled AA6xxx sheet (typically 1 mm thick) to be used for body-in-white (BIW) applications for auto body panels (Hirsch, 2004, 2014). The final metallurgical step prior to the shipment of these panels to manufacturers involves a solution heat treatment (SHT) reverting the ageing products of the alloys into solid solution and the product is then shipped to the customer. During this shipping time and while sheets are waiting to be used, the natural ageing (NA) process occurs whereby the strength of the alloys increases resulting in reduced formability. This can result in a product that is unable to meet the formability demands of the automotive manufacturer. As a result, industry has moved towards performing pre-ageing (PA) treatments to prolong the “shelf-life” of the material prior to it having insufficient formability. Once formed into BIW panels, the parts are then painted and subsequently undergo the paint curing heat treatment which consists of a short period of time at medium temperature, typically 20 minutes at 170–190°C. This short artificial ageing (AA) treatment, known as the paint bake (PB), provides additional strength and improved dent resistance for the material, but reduced formability. The PB result is strongly dependent on the PA treatment performed prior to the forming operation. Furthermore, the addition of copper (Cu) to a base Al-Mg-Si composition is known to increase the alloy’s strength. The goal of this work is to study the effect of Cu on strength, strain hardening, and strain-rate sensitivity (SRS) of these alloys, to understand the strength-formability compromise, for two separate heat treatment schedules; one including and one excluding the PA treatment, both followed by NA."

Jan 1, 2018

By M. Oliazadeh, A. Vazirizadeh

"The inclusion of small amounts of silicon, phosphorus and sulphur in iron ores or concentrates can have a profound effect on the steel making process and thus on the final iron and steel products. In nature however, it is inevitable that iron deposits contain unwanted elements. Each element has its own distinct effect on the final steel product. The effect of high silicon is the formation of gray iron. Phosphorus mainly increases hardness and strength, lowers solidus temperature and increases fluidity and cold shortness. Finally sulphur contamination causes cracks in the iron texture when smelting and forms white iron when casting. Overall, the acceptable level of phosphorus, sulphur and silica in the iron concentrate should be less than 0.04%, 0.15 % and 1.5 % respectively.Scarcity of high grade iron ores necessitates using lower grade ores with higher amounts of impurities. The purpose of iron concentrators is to increase iron grades to an appropriate level suitable for steel making as well as removing impurities. Although many impurities can be traced in the ore, the most predominant impurities are limited to one or two elements. In this paper the beneficiation methods for removing SiO2, P and S are presented, including flotation, and the parameters that need to be considered in the design of beneficiation plants are discussed. Finally industrial cases are discussed along with their metallurgical performance.INTRODUCTIONIn metal sector, value of iron ores and concentrates is determined by iron percentage as well ascontent of:• Useful elements (Mn, Ni, Cr, V, Ti): natural alloying elements in steel• Deleterious impurities (S, P, As, Zn, Pb, K, Na): impair metal properties or complicate operational process in blast furnace• Fluxing components (Si, Ca, Mg,, Al)Sulphur and copper result in red-short, phosphorus is the cause of cold brittleness and arsenic and copper decrease welding characteristics. Sulphur should not exceed 0.15 in commercial ore. Acceptable sulphur content in ores and concentrates for producing sinter and pellets is 0.6%max, as sintering and heat hardening of pellets remove sulphur 60-90%. Phosphorous content in ores, sinter and pellets is limited to 0.07%-0.15%. 0.00.1% As max, 0.1-0.2% Zn max and up to 0.2% Cu are allowed in iron-ore part of the blast furnace burden for the production of standard conversion pig iron. Slag-forming components are divided into basic oxides (Ca, Mg) and acidic (Si, Al). Higher ratios of basic to acidic oxides are preferred since this reduces raw fluxing material."

Jan 1, 2016

By J. W. Reynolds

Use of crushed waste rock recovered by sink-float separation from normal ore production for backfill is an established procedure at Commco's Sulhvan mme, Kimberley, British Columbia. Need for a safe method of placement in voids which were difficult to reach by gravity methods led to a co-operative venture with Radmark Engineering Ltd. in the development of a workable pneumatic transportation system for rock material. This paper reviews work done to date in a current program, and includes comments on the nature of the fill so placed, options for cementing such fill, implications for other aspects of mining and references to other applications of the system by other organizations who exchanged experiences with the Sullivan mine staff during the five-year period reviewed.

Jan 1, 1972

By William C. Browning

An economic drilling programme is one which costs the !east in chemicals, equipment, and time. The basis for such a programme with rotary drilling techniques is a drilling fluid in which bentonites do not swell. This is recognized in the growing trend toward gyp and other inhibited mud systems. Therefore, even though the mechanism of thinner action is a subject of applied colloid ,chemistry, the understanding of this mechanism is of economic importance in controlling the flow properties of inhibited muds. In phosphate, or sodium tannate, conditioned muds that are relative-!y free of contaminating-electrolytes, the thinner, or dispersing agent, is adsor.bed, ?creating an electrical double layer about the clay particles. The mutual repulsion of these charged particles effects colloidal stabilization, or deflocculation of the suspended clays, as discussed by Norton and others. In inhibited muds, however, the electrolyte concentration in the filtrate is sufficient to collapse the double layer and flocculation of the mud solids occurs, as evidenced by increased viscosity and gel values. Chemicals to control the flow properties of inhibited muds, therefore, are vital to the successful use of these systems as it is not always economical to adjust flow properties by watering back. Flocculation of suspended particles, as indicated in the work of Vervey, Overbeek, and others, is due primarily to gravity-like, long-range Van der Waals forces. Prevention of flocculation may, therefore, be secured by the interposition of any barrier between the particles, the thickness of which approximates the extension of the Van der Waals at-traction. Organic polyelectrolytes, such as Kembreak, Rayf!o, and Q-Broxin, may act to increase the double layer charge when used in small amounts in fresh-water muds. More important, however, is the fact that in inhibited muds an increase in concentration of the polyelecholyte permits the formation of a condensed film adsorption layer of the polyelectrolyte about the clay particle. When this occurs, the extremely viscous condensed adsorption layer creates a mechanical. barrier that prevents flocculation of clays, even in the presence of inhibiting concentrations of elecholytes. Rheological evaluation of the degree of deflocculation, or colloidal stability, may be made by utilizing the known effects of particle inter-action and volume concentration on the flow properties of suspensions. Rheological evaluation should be supplemented by direct microscopic or ultra-microscopic observation.

Jan 1, 1958

By G. Gauvin

Life span of aluminum smelting electrolysis cells can reach up to 3000 days. During this period, cathode blocks go under various physical and chemical changes that could result in an increase of electrical resistivity. The increase may be due to carbon migration from the cast iron to the steel bars, gap evolution between the cathode block and the cast iron, cathode cracking, etc. This paper focuses however only on the collector steel bar electrical resistivity evolution. To reveal the main phenomena responsible for the electrical resistivity increase, chemical analysis, metallographic and electrical resistivity tests were conducted on two steels bars picked from two Hall-Héroult cells after autopsies. Cathode voltage drop and temperature were measured using electrically insulated internal probes and thermocouples on 16 samples from each steel bar. Electrical resistivity can reach up to 1.21µO-m for a steel bar aged 2505 days compare to 0.142µO-m for steel AISI 1008 at room temperature.

Jan 1, 2011

By Frank D. Shepherd

THE Gunnar Gold Mines property is on the west shore of Beresford lake, in the Rice Lake mining division, southeastern Manitoba. Gold was first discovered in place in the Rice-Beresford Lakes area in 1911 on the Gabrielle claim, now included in the San Antonio Mines property at Rice lake. Following an eastward trend of favourable prospecting ground, promising showings were next staked in the vicinity of Long lake during the years 1915 and 1916. At that time, William Walton and associates, among them Gilbert LaBine, staked the Eldorado vein, north of Long lake, and Eldorado Gold Mines, Limited, was formed to develop the property a Company that, later, was to become widely known through successful operation of its radium-silver mine at Great Bear lake, Northwest Territories. Continuing eastward from Long lake, Walton and his partners, Gunnar Berg, Leo Seaberg, and Wm. Quesnel, staked claims during the years 1920-24 in the vicinity of Beresford lake which, later, were to become incorporated into the Gunnar Gold Mines property. The presence of gold-bearing quartz on these claims had been known from the time they were staked, but an opportunity to consolidate them into a group was not forth-coming until early in the year 1933. Although promising gold showings had been disclosed during the performance of assessment work on individual claims, no continuous mineralization having mine-making possibilities was discovered until after the consolidation of the entire group. From this stage onward, progress was rapid. Active exploration was begun on August 1st, 1933, and late in October James Houston reported favourably on the property. On October 27th, Gunnar Gold Mines, Limited, was incorporated in the Province of Ontario to develop and operate the property. The Company is also registered in Manitoba. The authorized capitalization is 3,000,000 shares of $1.00 par value. Gilbert LaBine was appointed president of the Company, with James Houston as mine manager. Following completion of a diamond-drilling programme, planned in 1933, it was decided to install a mine plant capable of carrying development to a depth of 1,000 feet. A transmission line, 5 miles in length, was built to the Great Falls-Central Manitoba line of the Manitoba Power Company, Limited.

Jan 1, 1939

By M. Takebayashi, M. Shingu, H. Nagai, T. Nakai, S. Asano

The Toyo Smelter and Refinery, owned by Sumitomo Metal Mining Co., Ltd. (SMM) is located in the coastal zone of Saijo City and Niihama City, Ehime Prefecture, Japan. The refinery has been producing copper, sulfuric acid, and precious metals such as gold, silver, and PGMs. Previously, the process of precious metals recovery was a combination of pyrometallurgy and an electro-refining process with the conventional cupellation for around 400 years. However, this process had some major problems such as non-efficient recovery of valuable metals, high environmental risk by pyrometallurgy, high cost for maintenance of equipment and so on. In order to solve these problems, a thorough hydrometallurgical process for precious metals refining using chlorine leaching technology was originated and developed by Sumitomo and thereafter commercialized in 2004 at Toyo Copper Smelter and Refinery. This new process enabled shorter-term recovery of gold and manpower saving, and occupational safety and working conditions have also been improved. Superiority over the existing hydrometallurgical processes was also confirmed, for example by the achievement of 99.99% pure silver production without an electro-refining process. This paper summarizes the hydrometallurgical technologies for precious metals recovery such as chlorine leaching of copper anode slime for silver recovery, solvent extraction (SX) for gold recovery, and ion exchange (IX) for PGMs recovery. It also presents a unique silver purification process. INTRODUCTION Sumitomo Metal Mining Co., Ltd. (SMM) produces copper, precious metals and rare metals as by-products at the Toyo Copper Smelter and Refinery, and nickel and cobalt at the Niihama Nickel Refinery. Precious metals contained in nickel ore are also separated and refined at the Toyo Refinery after concentration. SMM has been refining precious metals using the pyrometallurgical method. In recent years, we have revamped the separation and refining process of precious metals dramatically by making use of advanced hydrometallurgical and engineering technology developed in the company. In this paper, we introduce the history of development and techniques of this process, and also introduce in detail the technologies of gold refining, PGMs recovery, selenium recovery, and silver refining which have been particularly difficult to achieve.

Jan 1, 2019

By I. P. Swainson, A. Ilbagi, H. Henein

Powders of Al-50wt%Ni, Al-40wt%Ni and Al-36wt%Ni were produced using the Impulse Atomization technique, a rapid solidification technique. The molten droplets were cooled in-flight by the stagnant helium or nitrogen in the atomizing chamber. The resulting powders were sieved into different size ranges. X-Ray diffraction and neutron diffraction were used in order to quantify the phase fractions in the samples. The computer software GSAS was used to calculate the weight fraction of the existing phases, namely Al3Ni2, Al3Ni and Al, by profile refinement method. The effect of processing parameters, alloy composition and particle size will be discussed in this paper. In brief, no AlNi was found in any of the samples analyzed. Higher cooling rates resulted in the reduction of the ratio of Al3Ni/Al3Ni2. Also, at high cooling rates, Scheil closely predicted the ratio of Al3Ni/Al3Ni2. Some metastable phases were found in Al- 36wt%Ni.

Jan 1, 2010