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By Alan Bauer

IN RECENT PAST YEARS, the mining industry has expanded rapidly and mining engineers have not been generated in sufficient numbers to sustain this growth. Canada has not been alone with this problem, which has resulted in considerable soul-searching as to what the solution might be. Because of the unfavourable economics of running small departments such as mining, metallurgy, ceramic engineering, etc., one approach in some cases has been to put these departments together to form a department of mineral science which now has a broader base structure. Another solution has been the "conversion kit" program which has been conducted both at universities and in industry. At universities, such programs have consisted of converting graduates of other engineering disciplines into mining engineers. In some of the large mining corporations, extensive training programs have been used with the same aim.

Jan 1, 1972

By M. M. C Jiménez, D. C. Buzzi, D. C. R. Espinosa, J. A. S Ténorio, G. F. R Oliveira

In this work the extractive and selective capacities of solvent extraction synergistic systems to recover nickel and cobalt were evaluated. The liquor used was from the high pressure acid leaching process (HPAL). Initially the industrial liquor, processed from lateritic ores, was analyzed to identify the concentrations of the metals. Experiments of synergistic solvent extraction were performed later. The extraction liquid-liquid was carried out with a mixture of Cyanex 272 (CY) and Ionquest 290 (IQ) extractants. The process was executed with the temperature of 65 ºC, pH of 5.2 and the ratio aqueousorganic 2:1. Systems of 80% kerosene and CY 20%, CY 16% - IQ 4%, CY 12% - IQ 8%, CY 8% - IQ 16%, CY 4% - IQ 16%, IQ 20% were studied during 20 minutes. The results of this paper showed that the mixture of these two extractants doesn’t improve significantly the recovery of nickel and cobalt from liquor.

Jan 1, 2014

By P. J. Dunlop

THE object of this paper is to present a brief survey of the work done and the results obtained in controlling dust at the Hollinger Consolidated Gold Mines milling plant. The plant includes all primary and secondary crushing, grinding, and treatment operations. The major items of equipment are: (1) Underground Crusher Plant 1 48 in. by 60 in. jaw crusher, crushing run-of-mine ore to minus-6-in. Rate: 420 tons per hour (2) Surface Crusher Plant 3 No. 772 gyratory crushers 3 4 ft. by 16 ft. trommel screens 4 No. S gyratory crushers Reducing ore to rninus-172-in. Rate: 420 tons per hour (3) Roll Plant 5 sets of 62 in. bJ: 24 in. rolls 7 5 ft. by 10 ft. v1bratrng screens Delivering a minus-3/16-in. finished product Rate: 420 tons per hour (4) Grinding Plant 4 7 ft. by 15 ft. low discharge grate ball-mills 4 12 ft. reciprocating rake classifiers Rate: 4,800 tons per 24 hours Maximum capacity: S,800 tons per 24 hours

Jan 1, 1939

"The content of production reports has its origins in raw measurements taken in harsh production environments. The ensuing measurement/estimation errors always affect reproducibility such that, regardless of the fact that they are balanced through statistical data reconciliation, reported numbers are simply the most probable values of inferred probability distributions. This has important implications for how metal recoveries should be monitored and reported. Indeed, in a context where many process optimisation activities are based on small improvements in recovery, there should be no doubt that inadequate handling of measurement/estimation errors can easily exaggerate or mask actual changes in process performance. However, estimates of the reproducibility of reported metal recoveries are rarely reported to plant management. This situation persists despite the fact that a code compliant metal accounting system must inform management about business risks related to metal accounting. To this extent, this paper focuses on the continuous management of reproducibility level of metal recoveries in compliance with the best practices. Sensitivity analysis of primary and secondary metal accounting models is performed to show the resulting probability distributions for metal recoveries. Some guidelines are given for designing and managing metal accounting systems capable of achieving and sustaining predefined levels for the reproducibility of metal recoveries.INTRODUCTIONEach and every mineral processing plant produces daily, weekly and monthly production reports in which metal balances for payable and penalty elements are presented. While such production reports are usually consulted in offices, underlying raw measurements are taken in harsh production environments where mechanical vibrations, humidity, corrosion and dust, to name a few, disturb measurement procedures. It is thus no surprise that several authors (Francois-Bongarcon & Gy, 2002; Gaylard, Randolph, & Wortley, 2014; Holmes, 2010; Spangenberg & Minnitt, 2014) have reported pervasive issues related to mass/sampling measurements in the context of mineral processing."

Jan 1, 2016

By A. Hayatdavoudi, D. Chitila, F. Boukadi

"Shale oil and gas have provided a tremendous boost to energy production in the United States even though the characteristics and behavior of shale are yet to be fully understood. Hydraulic fracturing is often applied to horizontal shale wells to stimulate production. This experiment seeks to determine effects of cyclic variable temperature, water vapor and exposure time on shale micro fracture propagation. We used 22 small Pierre shale specimens and subjected them to aforementioned conditions. Fractures developed in 19 specimens. Combination of high temperature and high water vapor generated the largest number of micro fractures on the specimen surfaces.INTRODUCTIONShale oil and gas have contributed immensely to energy independence in the United States. Most if not all shales depending on their total organic content (TOC) and their clay content bear the promise of being a source rock. For example, the Eagle Ford shale play, located in south Texas, is one of the key contributors to the recent rise in oil and gas production in the United States. Data from the U.S. Energy Information Administration (EIA), published in 2014, states that monthly oil production from Eagle Ford wells increased from 340 barrels per day (bbl/d) in January 2009 to nearly 1 million bbl/d in June 2013. Natural gas production has also increased at a similar rate over the same period, from 5.8 million cubic feet per day (MMcf/d) to nearly 4,000 MMcf/d (EIA, 2014).According to the railroad commission of Texas (RRC) 2014 published information, the Eagle Ford shale play is an important play because it produces gas and more oil than other shale plays in the United States. It is an organic-rich play with carbonate shale percentage in the 70% range in south Texas and the shale content increases moving to the northwest. High carbonate proportion renders this play brittle and suitable for hydraulic fracturing treatments."

Jan 1, 2015

By James D. Bittner

Separation Technologies, LLC (ST) has developed a processing system based on triboelectric charging and electrostatic separation that provides the mineral processing industry a means to beneficiate fine materials with an entirely dry technology. The environmentally friendly process can eliminate wet processing and required drying of the final material. The process requires little if any pre-treatment of the material other than grinding and operates at high capacity ? up to 40 tonnes per hour by a compact machine. Energy consumption is low, approximately 1 kWh/tonne of material processed. Since the only potential emission of the process is dust, permitting is typically relatively easy. In contrast to the other available electrostatic separation processes that are typically limited to particles greater than 75 µm in size, the ST belt separator is ideally suited for separation of very fine (<1 µm) to moderately coarse (300 µm) materials with very high throughputs. The triboelectric particle charging is effective for a wide range of materials and only requires particle ? particle contact. The small gap, high electric field, counter current flow, vigorous particle-particle agitation and self-cleaning action of the belt on the electrodes are the critical features of the ST separator. The high efficiency multi-stage separation through charging / recharging and internal recycle results in far superior separations and is effective on fine materials that cannot be separated at all by the conventional electrostatic techniques. Since 1995, this triboelectric process has been extensively used for the beneficiation of coal fly ash with eighteen separators in place and over 130 machine-years of operation at locations in North America and Europe. ST has also installed separators for the beneficiation of industrial minerals in North America and Europe. The technology has been successfully applied to the beneficiation of a variety of minerals including calcium carbonates, talc, barite, and potash.

Aug 1, 2013

By S. Shrestha

Magnesium-based alloys are of growing interest for many industrial applications due to their favourable strength-to-weight ratio and excellent castability. Mass reduction has advantages in many industrial sectors for example, in automotive, a reduction in mass improves fuel economy and can lead to more efficient mechanical systems by reducing the weight of moving parts like wheels, gears, pistons. However, the relatively poor corrosion and wear resistance limits the use of magnesium and its alloys in many potential applications. The patented Keronite® plasma electrolytic oxidation (PEO) process enables manufacturers to overcome such problems and, in its latest generation equipment has been developed to industrial realisation for high volume production. This paper presents microstructural characteristics and corrosion performance of two most widely used high pressure die-cast magnesium alloys AZ91D and AM6OB with a duplex corrosion protection coating system that comprised a thin Keronite pre-treatment followed by a subsequent automotive grade final powder coat.

Jan 1, 2006

By Robert H. Clark

Introduction During the last twenty years, science and industry have been strenuously endeavouring to discover new sources and new kinds of liquid fuels and to work out suitable chemical methods for their production. One of the new possibilities for the production of liquid fuel on a large scale is law-temperature carbonization of various grades of coal. The use of alcohol as motor spirit, in spite of its relatively low calorific value, is being widely investigated. Its production by fermentation of sugars, its recovery from the sulphite liquors of the paper industry, its production directly from wood and also from calcium carbide, have all been considered. At present the most promising line of investigation would appear to be the further development of those technical processes which yield liquid fuels from coal; since science has shown the possibility of preparing all kinds of liquid fuels and even the complete conversion of coal into oils. The present paper will consider briefly: 1. The production of primary tar by low temperature carbonization of coal. 2. The hydrogenation of coal. 3. The synthetic processes of Dr. Franz Fischer.

Jan 1, 1928

By Alan D. Brown

"Diesel-electric trucks are those that have some portion of the convention-al mechanical drive train replaced by electrical components. As larger and more powerful diesel engines appeared, the development of mechanical transmissions and related drive components failed to keep pace, and electrical generators and drive motors therefore came into use as an efficient means of transferring the mechanical energy of the engine to the driving wheels of the vehicle.The Berkeley Pit has been a major testing ground for the evolution of this type of truck. We now operate a haulage fleet consisting of conventional diesel trucks and two different types of diesel-electric trucks. There-fore, we have been able to obtain an interesting comparison of costs and performances between these three types of haulage units.In all phases of operation, the diesel-electric truck commands a favourable advantage over the conventional diesel truck, and represents a more efficient and less costly means of haulage. Nearly all manufacturers of heavy-duty trucks are now building, or have plans to build, such a truck."

Jan 1, 1966

By Lorrie Fava

Two needs in the mining industry, to enable overall process improvements, are open systems and network connectivity in underground mines. The Pando project, a collaboration between Symboticware, Vale and Xstrata Nickel, and supported by CEMI, addresses these issues, and leverages the solution platform to deliver intelligent applications. An open system is one that uses publicly available standards for its key interfaces. Vendor-neutrality and ease of information flow are two main benefits that result from the use of open systems. By facilitating the interoperability of systems, open systems allow information to be available when and where it is needed for decision support. Network connectivity in underground mines is typically limited, with hotspots in strategically chosen areas that are relatively static. Mobile equipment moving through a mining work cycle experiences intermittent connectivity; in this situation, seamless remote equipment monitoring is impossible. The Pando project establishes an open technology platform, adhering to the IREDES and OPC UA standards. It enables the collection and integration of information generated by mobile equipment? seamlessly while there is a network connection, and as a store-and-forward gateway to manage intermittent connectivity. The platform capabilities are leveraged to support embedded intelligent applications. This open platform, the SymBot, is a rugged hardware and software device. The platform complies with open standards for industrial automation and systems interoperability. The SymBot platform is capable of providing advanced real-time decision support at the device level, and is designed to be remotely configurable. Applications being developed through the Pando project include engine monitoring, a dynamic load weighing system, machine location monitoring and automated activity monitoring including production and maintenance reporting.

Oct 1, 2010

By K. S. Raja, B. Pesic, S. Kshetri

"We investigated the electrochemical corrosion behavior of commercial permanent magnetic material (NdFeB alloy) in 0.1 M NaH2PO4 solution (pH:4.75) containing 0 – 1000 ppm of chloride at room temperature (298 K). The material was evaluated in magnetized and demagnetized condition with different surface preparations such as: Ni-Cu-Ni coated, uncoated (bare), and anodized (in fluoride containing ethylene glycol at 60 V for 15 minutes to form a thick nanoporous oxide surface). The nickel coated magnetic sample showed reasonable pitting corrosion resistance up to 100 ppm chloride addition. The uncoated samples showed passivity in chloride free phosphate solution. Chloride additions caused pitting and the pitting protection potential was equal to the corrosion potential with 100 ppm chloride addition. Demagnetization did not alter the electrochemical polarization. However, the passive film formed on the magnetic sample showed higher charge carrier density than the film formed on the demagnetized sample. INTRODUCTIONSintered NdFeB permanent magnets exhibit excellent magnetic properties such as large energy product [(BH)max > 450 kJ/m3], high saturation magnetization (1.6 Tesla), and high coercivity (1.2 – 2.08 x 106 A/m) (Sugimoto, 2011). However, the NdFeB magnets are prone to corrosion attack because of the presence of Nd-rich intermetallic phases, such as Nd4Fe (Jurczyk & Jakubowicz, 2000). Nd-rich and B-rich intermetallic phases are distributed in a matrix of Nd2Fe14B tetragonal ferromagnetic compound in a permanent magnet. Generally, several types of Nd-rich phases are present in the magnet with Fe:Nd ratios ranging from 1:1.2 to 1:7. The volume fractions of Nd-rich and B-rich (Nd1+xFe4B4 type) phases are about 10% and 7% respectively (Li, Ma, Li, & Wang, 2011) . Among these intermetallic phases, Nd-rich phase has the most active electrochemical potential. Therefore, dissolution of this phase occurs in preference to other phases by galvanic corrosion when exposed to moisture. Since Nd-rich phases are present at the grain boundaries of the Nd2Fe14B matrix, corrosion leads to disintegration of the magnet."

Jan 1, 2012

By N. R. Thornton

This paper discusses the rapid growth in the application of instrumentation for metallurgical process control. It covers such methods as ultrasonics, pulp density measurements, on-stream X-ray analysis and reagent control, as well as the expanding use of computer control and data acquisition.

Jan 1, 1971

By G. M. Mason

History Due to its strong affinity for oxygen, aluminium as an element was isolated only after many other rarer metals had been prepared and studied. It was just over one hundred years ago that two scientists, Hans Christian Oersted and Friedrich Wohler, produced the first few pellets of aluminium and determined its physical properties. These early investigators used metallic potassium as a reducing agent. Later, St. Claire Deville, by using sodium instead of potassium, improved the yield in the reduction and produced some pounds of aluminium. From a figure of about $110 per pound in 1855, the price had fallen to about $4 per pound by 1886. In that year, a very important discovery was made independently by Charles Martin Hall in Oberlin , Ohio, and Paul . Heroult in France. Stated in its simplest terms, the discovery of Hall and Heroult was that aluminium could be produced by electrolyzing a solution of the oxide in molten cryolite. The application of the Hall-Heroult process made the metal immediately available in commercial quantities and, by 1900, the price had fallen to 23 cents per pound. The growth of the industry in the past fifty years is well known, and is outside the scope of this paper. It is, perhaps, not generally known that aluminium was first produced in Canada at Shawinigan Falls in 1901. Since that time, production has been continuous at one or more smelters in the Province of Quebec. The largest of these smelters, which is also the largest aluminium smelter in the world, is at Arvida, Quebec, on the Saguenay river. A large power potential and access to ocean shipping were the two principal reasons for the establishment of aluminium production facilities in the Saguenay district. It is interesting to note that the aluminium industry, as a large user of power, took an active part in the early industrial development at Niagara Falls and Shawinigan Falls, and is now repeating the process in the Saguenay valley.

Jan 1, 1949

By Vishal Shukla, Prateek Singh, D. P. Chakraborty

"Continuous thickening by an operation called sedimentation is the separation of suspended solid particles from a liquid stream by gravity settling. The primary purpose of thickening is to increase the solids concentration of the feed stream. High rate thickeners are designed specifically to maximise the flocculation efficiency. A detailed investigation has been carried out to understand the influence of ore type and operating parameters such as bed level, bed mass, rake arm torque and flocculent concentration on thickening operation. Tata steel’s Noamundi plant data shows that variation in ore type, and operating parameters are major contributors to fluctuation in thickener performance. A lot of research has been done earlier on thickening operation but effect of ore type and operating variables by using plant data was never touched before.In this context, the performance of thickener was evaluated by daily data to study the influence of ore type and operating variables on thickener operation. Investigation shows that friable ore % in feed mix is proportional to slime density because friable ore is porous & brittle in nature. As a result, friable ore generates more fines/ultrafine during communition process in wash plant. Increase in flocculant concentration and bed mass is showing a positive change on high rate thickener performance Investigation shows that optimum bed mass and flocculant concentration is required to achieve desired pulp density in thickener underflow at different feed pulp density (g/cc).INTRODUCTIONOver the years, Iron Ore Beneficiation at Tata Steel, Noamundi has seen varied changes. Depletion of high grade iron and with increasing iron ore throughputs coupled with lowering of the hard ore a subsequent increase in slime generation, slime management and clear water requirement for wet Plant has thrown up myriad challenges. To overcome these challenges, many improvements initiatives were taken by Tata Steel in last decade. One of the major changes is the recent High Rate Thickener commissioning at Tata Steel Noamundi to cater the high iron ore throughput requirement. Slime reporting to Thickener has increased from 1.4 MTPA 2.5 MTPA over the last few decades. The above changes further aggravate the poor settling and dewatering characteristics of the slurry which is being feed to HRT. Considering the above mentioned constraints and stringent environmental implication proper water management has become a major challenge to reckon with. The thickener is used to increase the concentration of the suspension by sedimentation, accompanied by the formation of a clear liquid. In most cases the concentration of the suspension is high and hindered settling takes place."

Jan 1, 2016

By Ernest A. Hodgson

WHEN excavations are made, at depth, in hard brittle rock structures, as in certain mines in India, in South Africa, and in Ontario, the pressure due to overburden, together perhaps with inherent geologic strain, tends to become concentrated in the walls of some of these openings and the rock bursts, often closing the adjacent drifts and scopes and presenting a serious menace to the miners. Where the rock is much fractured and faulted, the danger is greater, since the pressures tend to shift without warning from point to point, sometimes within a few hours. Attempts have been repeatedly made to find some physical property of the rock which will change with pressure, which can be measured for rock &apos;in place&apos; in the mine, and which will give an indication of the state of strain, thus warning of an approach to bursting conditions. Some of the properties tested have been the speed of propagation of elastic waves in the suspect rock, variations in temperature due to pressure changes, rate of closure of openings or shifts along fault planes, strain gauge measures, and others. Each of these has proved unsatisfactory for the purpose. The most promising method so far proposed has been the study of the very faint, sub-audible snaps (microseismims) which are produced in rocks under pressure. Such a study has been in progress at Lake Shore Mines since May, 1942. Instruments designed to pick up, amplify, and record the microseismims were perfected and a programme of observing, using the microseismic method, has been carried through with persistent diligence and at considerable expense. In 1943, experience with the method in a pillar section on the west side of the Lake Shore mine gave much promise of predicting bursts. A very heavy burst on January 29th of that year occurred in the exact section of the mine covered by the instruments, and the records indicated a measure of prediction. In response to repeated requests for information, a number of reports were given out, among others a radio talk by the writer over CJKL (Kirkland Lake), which was reported in full in the Northern News . Also, a detailed account of the occurrence was given in an illustrated paper by the writer (l).

Jan 1, 1945

By J. F. Magee

THERE is nothing new about drag-line dredging for placer gold. The use of the separate unit for excavating preceded the large barge with bucket-line excavator mounted upon it, which has developed to a high state of perfection through use in every part of the world. But at present there is a vogue for a small, inexpensive plant to work economically the shallower gold gravel deposits that the bucket-line dredges do not work. The dragline dredge consists of the drag-line excavator, on caterpillar mounting on the edge of the dredging pond, which feeds the gravel to the washing plant, mounted on a floating barge in the pond. There have been more than twenty-five such plants built and operated in central and northern California and an unknown number in other States. There have been variations in details of design but the essentials are similar in all. I wish to describe the operation of a typical drag-line dredging plant, that of the Wyandotte Gold Dredging Company on the Farnan Ranch in the Oroville district. This organization of six active partners built their first plant on Wyandotte creek in the autumn of 1933. The operation was successful due to wise management, which was based upon good plant design and proper principles of operation. The partners elected one of their number, H. F. England, as manager with full control and responsibility. This plant and operation furnished the pattern for many subsequent ones.

Jan 1, 1937

By J. W. McCammon

CRANGES in construction ideas and the continually rising costs of labour and conventional building materials, particularly since World War II, have prompted widespread investigations into the development and adaptation of new materials to meet the new requirements and to help reduce costs. Lightweight aggregates have been prominent in these investigations. The lightweight aggregates most commonly used today are foamed slag, cinders, pumice, diatomite, exfoliated vermiculite, expanded perlite, and bloated clay or shah. Lightweight aggregates contribute to the building industry in several ways: ( 1) in large structures the reduction in deadweight effected by the use of lightweight materials reduces the amount of reinforcing and structural steel necessary to support the structure; ( 2) the decrease in weight of lightweight blocks makes handling easier and faster; (3) pre-fabricated floor and roof slabs and tilt-up walls of lightweight concrete have become feasible and popular; ( 4) lightweight aggregate concrete has good nailability and is easily channelled; (5) concrete and plaster made with lightweight aggregate have good heat and sound insulation properties.

Jan 1, 1957

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 R. C. Reed, L. T. Wu, H. C. Harada, K. Kawagish, R. T. Wu

Oxidation of pure metals is a chemical reaction in which the metal loses one or more electrons, such that the atom of the metal changes from the neutral state to a positively charge ion and reacts with oxygen to form an oxide of the metal. The oxide can form as a protective and adherent scale that slows down further oxidation, or may spall off repeatedly, exposing fresh metal surface to react with oxygen. In multi-component alloy systems such as typical high temperature NiCrAlY bond coats, more than one oxidation mechanism may take place at once and thus, complicates the study of oxidation. To better understand the competition between formations of oxides of different compositions, a thermodynamic assessment is carried out to study the oxidation mechanism of a Ni-27Cr-9Al (at %) ternary alloy. Based on the assessment, it is demonstrated that the layering of different oxides can be determined, with the most stable oxide (alumina) existing directly above the metal-oxide interface and the least stable oxide (nickel oxide) locating on the outer most layer. A comparison between the calculated results and previously published experimental observations shows excellent agreement.

Jan 1, 2010

By M. Potesser

Higher prices for natural gas or oil have motivated the copper industry to reexamine the modes of oxygen and oxy-fuel burner usage at operating plants. With rising energy costs and the growing importance of environmental protection, burner usage and burner operations have become the focus of several investigations and optimization efforts. One possible approach to lower energy usage is through combustion using tonnage oxygen. When such oxygen is used, the flame temperature increases and operational efficiency is improved. As well, with the correct technology, due to the presence of lower levels of harmful substances such as NOx in the off gas, there is improved environmental performance. As regards copper production, furnaces are employed for both concentrate smelting or for melting and casting operations. The use of tonnage oxygen in concentrate burners for smelting provides for a higher thermal efficiency. For furnaces employed for melting, air-operated burners may in fact have an initial advantage because a long radiant flame is typically generated, thus providing for a higher degree of heat transmission. This paper describes the new experimental burner chamber of Messer Austria GmbH which provides for testing of the combustion of natural gas with oxygen or oxygen-enriched air and the use of special water cooling ducts that simulates a metal charge during melting, The operational effectiveness of the burner is determined from temperature and off-gas analysis data. The paper also discusses future trends in burner technologies including a new patented burner. Cu2007 - Volume III (Book 2) The Carlos Diaz Symposium ou Pyrometallurgy Edited by A.E.M. Warner, C.J. Newman, A. Vahed, D.B. George, P.J. Mackey, A. Warczok Toronto, Canada,

Jan 1, 2007