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By Stuart Lister

"When MacLean Engineering chairman and founder Don MacLean got the first question from a minesite about the possibility of addressing ventilation limits through incremental fleet electrification, he was intrigued. It was back in 2015, and the MacLean scissor bolter was already diesel-electric (jumbo trailing cable), so it made sense to him that if they could engineer a battery drive system for the unit’s tramming cycle, they would have the inaugural electric vehicle (EV) MacLean unit.At that time, there were not any entirely diesel-free hard rock mines in existence on the planet, and that remains the case to this day — although the Borden project in northern Ontario is progressing toward that goal (see page 33). This meant there was essentially zero market demand for battery electric vehicles as well as a complete lack of battery technology to address the battery electrification of heavy haulage. Heavy haulage is the part of a typical mine’s mobile fleet with the largest footprint when it comes to diesel particulate emissions, greenhouse gases and wasted energy in the form of heat.Three years later — the wave of battery electrification that is currently picking up speed across the mining industry promises to hit full swing by the early 2020s when a slew of new build, diesel-free mines will start construction. But this movement toward emissions-free mobile fleets is not a completely new phenomenon. Instead, it is an updating of mining technology from a previous generation. What is going on now is the re-electrification of mining. Up until the 1960s, early generations of battery technology (lead acid) and electric locomotive systems were the norm for material and ore haulage in Canada and elsewhere.The thought of a coming paradigm change in mining was particularly pertinent to Don MacLean back in 2015, as he had been part of the era that ushered in the first generation of rubber-tire diesel equipment, when he was a divisional foreman with Inco in Sudbury in the 1970s. He was part of the operating team that was tasked to build a rail loop on one extraction level of the mine. At that time, events on the ground overtook the project, as diesel-powered mobile equipment became a viable option. Once the first diesel scoop was introduced at Creighton #3 shaft, it was clear what the power, haulage capacity and mobility could do for operations and that era of electric rail haulage underground was effectively over."

Jan 10, 2018

By P. Blonde

Recent analysis has suggested that a balanced recovery profile can improve flotation bank performance. Test work was conducted to test the balanced profile concept at the Penhorwood talc mine near Timmins, Ontario, Canada. Plant trials were devised to determine how to control the recovery profile and the resultant impact on grade and recovery in a rougher bank of four cells. Accompanying gas dispersion measurements revealed a maintenance issue with one cell that was corrected. By manipulating air and frother addition it was possible to bring the bank closer to a balanced recovery profile and the down-the-bank grade/recovery improved. Plant production showed an increased talc grade at similar yield with the balanced profile. The results provide justification for a long term plant trial.

Aug 1, 2013

By Cynthia Belt

"Energy management is critical to aluminum processing given the high energy requirements of melting and processing aluminum. Energy costs have always been a high percentage of the total production costs within this industry. Energy management at many plants relied on better technology that many times required high capital. As carbon management has grown in importance and project payback becomes more critical, a larger view of a plant's process is required. This paper looks at the energy requirement due to current typical practices in overall product recovery, metal loss, utilization, and technology to understand potential methods of reducing overall energy within a plant and within the aluminum processing industry.IntroductionFor many companies that process aluminum, energy is a major portion of their costs that can surpass the cost oflabor. Aluminum processing can include secondary processing of scrap and prime aluminum into sows and/or molten aluminum or casting aluminum by various methods such as direct chill, continuous casting, low or high pressure casting, mold casting, and extrusions. In the case of this paper, we are considering only plants that include the melting process as a portion of their process. The process of melting aluminum takes energy. In most cases, the aluminum must then be heat treated one or more times. Post processing of the aluminum includes rolling mills used for making sheet, extrusion lines, and machining such as saw cuts, drilling, or surface finishes that all take additional energy.While these high energy costs directly affect the profits of the company, energy management within the metals industry is still not widespread. A co=on misconception is that the solution to high energy costs is high cost capital equipment. While state-of-the-art equipment can certainly improve energy efficiency, it is not the only solution. To obtain a truly energy efficient plant, several directions needs to be addressed through an energy management thought process with a wider scope. Impact on potential savings is possible through: product recovery, metal loss, utilization, and new technologies. An understanding of the potential costs and savings from these means is important. Several of these methods provide low cost approaches to saving energy.The background data used in this paper is not a random sample within aluminum processing but yearly averages from various plants in different aluminum processing industries. As is normal in this industry, the plants have been under different corporate management over the years with different strategies for energy management. This data is not meant to be accurate for the entire industry but to suggest areas for energy efficiency work."

Jan 1, 2012

By G. X. Du

Improving reaction effectiveness of asbestos tailings and acid is main means to increase the productivity of magnesium hydroxide and amorphous silica and to reduce production costs. In this paper, the process optimization of acid-leaching reaction process of asbestos tailings is reported. Through the orthogonal experiments of four influence factors, such as acid consumption, reaction temperature, reaction time and initial acid concentration in the leaching reaction. The experiment results indicated that the optimal process parameters were as follows: reaction temperature was 95?, reaction time was 1.5h, acid consumption was 218.9g hydrochloric acid(37%) per 100g asbestos tailings and initial acid concentration was about 25%. The influence significance sequence of the four factors was as follows: reaction temperature > reaction time > mass concentration of hydrochloric acid > hydrochloric acid consumption. Under the optimum process conditions, the leaching rate of MgO was 97.3%, total iron 98.15% and Al2O3 57.9%.

Jan 1, 2014

"In addition to outstanding technical sessions and networking opportunities, the SME Annual Conference and Expo offers attendees a chance to see the latest and greatest technology that the industry has to offer. The 2017 SME Annual Conference and Expo was no exception as 575 companies filled 756 booths from Feb. 19-22 in Denver, CO. The following is a look at some of the vendors that were on hand.AIL MiningThe Edge, featured by AIL Mining at the 2017 SME exhibit, is a four-flange structural liner designed to be an alternative to structural plate’s traditional lapped seams and to help mine operators build more efficiently and safely. It is ideal for creating underground structures, such as mine shafts, ventilation raises and escape ways. The Edge is available on SuperCor structural steel plate — 10 times stiffer and five times stronger than traditional steel liner plate. It facilitates curved structures, both horizontal and vertical, and eliminates the need for ring beams. It is ideal for remote sites. For added safety, structures can be assembled from the inside, and the leak-resistant structures can be dismantled and removed easily. Brackets can be attached to mine shafts or vent raises to support Alimak rails or climbers. Similarly, brackets or hangers can be attached to drifts or tunnels to support mine air, water or electrical utility services.ArcadisMining companies spent nearly $12 billion on water infrastructure worldwide in 2014, reflecting the industry’s heightened concern about environmental issues and social, regulatory and political risks.So, with an increasing focus on water reuse and recycling, mining companies must have effective water management plans that include sustainable solutions. Also, many water quality issues fall under both state and federal regulatory jurisdictions. To solve these problems, Arcadis provides comprehensive ground- and surfacewater technical support in a complex hydrogeologic setting. It can characterize the nature and extent of mine-related constituents in ground water and surface water, as well as the complex interactions between the two waters, and prepare the operational permits needed by mine and tailings facilities. As an example, Arcadis constructed a hydrogeologic and geochemical conceptual site model that improved site understanding for a molybdenum mine in the western United States that spanned several watersheds. It also provided technical support for permitting and compliance issues, allowing the mine to return to active production."

Jan 5, 2017

By P. F. Mataich

When the subject of plant computers is brought up most people visualize the computer's controlling the entire plant with very little operator intervention. Actually, this picture is true today in only a limited number of cases and will certainly not be true in the minerals industries for many years to come. There are several ways in which a plant computer can significantly contribute to improving plant operation and closed loop control is only one of these. First of all, what are the basic ingredients for good plant control? For good plant control, two requirements must be met. First, the operator must get good information feedback from the process and then he must know what action to take in response to this information. Control information can be obtained through instruments, laboratory analyses, or through simple visual observation. If it is timely and accurate and the operator knows how to use it, then we have the makings of a good plant control system. The computer can be of help in both these areas by getting good data back to the operator and in helping to develop a good control scheme for the plant.

Jan 1, 1966

By K. L. Kayler

The Bardon Trimount, Inc. stone quarry in Ashland, Massachusetts was the recent subject of a quarry closure review report. The quarry produces aggregate using standard drilling and blasting techniques. Stone is processed at an on-site plant. Noise monitoring data collected during the closure review indicate that the quarry generally operates within the quiet range. There is a decrease in noise while the quarry is not operating. Levels of dust associated with the quarry are low. Unpaved roadways are the greatest contributors of fugitive dust associated with the mining operation. The quarry cannot be seen from any homes within the town of Ashland, except during the winter months. The visual impact of the quarry on surrounding properties is minimal. Further quarry development is likely to reduce visibility of the quarry from some areas.

Jan 1, 1995

By H. -Peter Sattler

The laser sorting technique for replacing the handpicking of the non-ferrous metal scrap from auto shredders was first introduced 1990, The process is based on the use of atomic emission spectroscopy induced by lasers to identify the scrap particles and sort them with adequate systems into main fractions of Al-, Zn-and Cu-alloys, stainless steel and lead, In the meantime the handling technique for the scrap, i.e. the singling and sorting technique as well as the analytical detector were further developed for more efficiency and higher reliability, i,e. less maintenance, minor sorting errors etc. These developments were mainly based, on and initiated by operational experiences from the startup phase of a first production plant. Part of the on going research work was the development of an ,aluminium detector which makes it the first time possible to sort mixed aluminium scrap automatically into specific alloy fractions.

Jan 1, 1995

By Terry J. Close

The Welcome Creek Wilderness has small, dispersed gold placers. Pockets in the 25.5 million yd3 (19.5 million m3) of alluvium along Welcome and Rock Creeks have as much as $5.61 gold/yd3 ($7.34/m3) at $500/troy oz ($16.08/g). All the alluvium averages 20.1 cents gold/yd3 (26.3 cents/m3). Because of the low average gold content large-scale placer mining would not be economically feasible. Small-scale selective pocket mining, however, may be profitable. The alluvium along the streams in the Wilderness has little apparent potential for production of sand, gravel, or stone because alternate sources are closer to markets. The four lode prospects known within the Wilderness appear to have low mineral potential. No oil, gas, uranium, or geothermal energy sources are known to be present.

Jan 1, 1982

By W. R. Phibbs

THE Columbia Steel Corporation, organized in 1922, and taken over by the United States Steel Corporation on Feb. l, 1930, is operating one blast furnace at Ironton, Utah, which was started on April 30, 1924, and is producing approximately 14,000 tons of pig iron per month. Half of the pig iron produced is basic iron and is used in its own plants at Pittsburg and Torrance, Cal. The ore for the blast furnace is shipped from Desert Mound, Utah, near Cedar City, in the southern part of the' State, approximately 231 miles from Iroaton. The ore is a hematite, disseminated with magnetite, the chemical analysis showing approximately 12 to 20 per cent magnetite, and under the micro- scope the ore has the appearance of a magnetite.

Jan 1, 1930

By Marco Castenetto

Some of the most significant Danieli innovations in the field of long products are the: i) The EWR® system, through automatic continuous head-to-tail flash welding of billets at reheating furnace exit side, enables uninterrupted production of the mill for endless rolling of straight bars, wire rod and bar in coils. The process is particularly beneficial to wire rod and bar-in-coil mills as it enables production of “customized-size coils” (any coil weight according to specific Customer request) and with extra-high final coil weight, even starting from low-weight billets; ii) The Spooler process is based on twistfree winding of hot-rolled rebars into highly-compact/ultra-heavy coils featuring a unique cobble-free un-coiling capability. This enables high-speed feeding of the downstream cold-processing lines with hot-rolled spooled coils coming directly from the rolling mill without the need of any traditional off-line operation (such as de-coiling, stretching & re-winding). The system results highly beneficial both to bar-in-coil producers and to the downstream lines operators. The latest step forward is the combined application of these two systems that has made it possible for endless rolling of spooled bar in coils, enabling to cumulate the benefits of the two processes, particularly as far as transformation costs are concerned.

Aug 16, 2017

By I R. Souza

At the mining industry, there are several uncertainties that may affect the mobile mining equipment fleet sizing and usage, such as commodity supply and demand, which impacts the mineral price, environmental licenses to allow operations and strategic decisions made by the own mining company. Due to that, it may happen to acquire a mobile mining equipment for a specific site and before it finishes the entire forecasted life cycle, the machine gets idle on that operation and a decision must be made regarding this matter. On large mining companies with several sites, equipment transfer provides a good solution to solve this issue and at the same time it provides operational flexibility and allows to use the equipment until the initially planned working hours. This article presents a method to compare technically and financially whether it’s more feasible to transfer a used equipment or to buy a new one. In other words, we will compare a brand-new machine versus a used one in terms of safety, net present value (NPV) considering both capital expenditures (CAPEX) and operational expenditures (OPEX), technological obsolescence, risks, equipment maintenance reliability and lead times. Although it’s not the main purpose of the paper, it will also be briefly discussed the importance of having a considerable amount of backup equipment to handle low likelihood and high consequence risks that may materialise. This backup equipment portfolio is particularly important to avoid loss of sales and profits in case the production plan changes and it demands further equipment than initially planned to cope with the forecasted production.

Nov 8, 2021

By Francois Mignard

With a limited global steel production growth, automotive application market shows interesting volumes and trends especially in emerging countries. The recent period has again enabled Siemens VAI to confirm a position amongst leading suppliers of new plants serving high-end steel production in particular for unexposed and exposed automotive material. With a series of recent plant references in operation and under construction, relevant answers to such sustained level of performances are highlighted along the downstream processes. Designed for a wide range of applications, Siemens VAI processing lines includes advanced technological and state-of–the art equipment, among them, Solid state laser welder, Pickling Tunnel tanks, Skin pass mill and Tension leveller, Side trimmer with dynamic width adjustment, and new generation of Automatic surface inspection systems. With a continuous aim of driving improvements, Siemens VAI has also developed Global Quality Monitoring solutions notably through advanced software which provide just-in-time warnings and assist steel makers in the daily operation of their lines. As lifecycle partner, Siemens VAI offers solutions and services in metallurgical expertise from metallurgical modelling, through physical simulation on rolling, annealing and galvanizing processes, and enables Siemens to accompany our customers along with their project definition till fulfilment of highest market requirements.

Jul 30, 2018

Mr. Tays (communication to the Secretary): Mr. Wynne's criticism of my paper* brings forward a few points which are really important, and might properly have been considered in the original paper. By calling attention to them he has rendered me a service. It is quite true, as Mr. Wynne says, that, in the tests reported by me, the Bryan mill was always working at a relative disadvantage, and my comparison of the work of this mill with that of the stamp-battery should be interpreted, therefore, so much the more favorably to the mill. Of course, wire screens can be used to advantage on the Bryan mill, if they are not of smaller size than 30-mesh; but

Jan 1, 1902

By Donald R. Simon

Money... not many subjects are as personal or as emotional. Hessiod said it well in 700 B.C. "Money is life to us wretched mortals". Are you getting paid enough? Does your company reward its top people? Does coal or copper pay more? Production or engineering? How is the synfuels industry going to influence mining salaries? Do high salaries attract and retain the best people? Do modern compensation systems ensure fairness or destroy entrepreneurial spirit? With our tax system and high standard of living why are we so salary conscious? Salary is not only important for what it can purchase but it is also a yardstick, measuring how well we are doing. We all need money to pay the bills and maintain our standard-of-living, but once we reach a certain point the psychological ramifications become more important than the purely practical side. Even necessary payments like the mortgage and the car are a function of our egos. Are our choices of cars and homes based on simple transportation and shelter?

Jan 1, 1980

By E. R. Hughes

Introduction Situated 182 miles east of Vancouver, on the Kettle Valley branch of the Canadian Pacific railway, the Princeton coal field is readily accessible to the Coast markets. The area covers approximately forty square miles and present indications are that the deposits should contain at least 300,000,000 tons of coal. Comparatively little development has yet taken place in this coal field. Since the commencement of recorded output, the collieries operating in this area have produced 1,640,518 tons of coal. The coal field proper includes only the Tertiary deposits adjacent to the town of Princeton and does not include the Coalmont or Nicola deposits. Production has never been on a large scale. The largest annual output from any property was 81, 780 long tons mined at the Granby colliery in 1940. Coal output was first recorded in 1909 and since that time fifteen properties are reported to have either mined coal or to have done prospecting or development work; of these, only two are presently active. However, none of the properties now inactive were closed because their coal resources were exhausted. The accompanying key map shows the extent of the Princeton coal field, and the location of the coal mines and prospects in this field General Geology The Princeton field is underlain by rocks of Oligocene age and is one of the series of more or less isolated Tertiary lake basins in which coal, or lignite, has been found in the interior of British Columbia. Resting on the Nicola group rocks of Triassic age, the Princeton sedimentaries consist of sandstones, conglomerates, shales, bentonite, bentonitic clays, and several seams of coal. Tertiary volcanics occur both above and below the stratified rocks and in places they have been thrust through the overlying measures. In some areas, the coal has been burned to a red ash as the result of vulcanism, while in other parts some of the moisture has been driven from the coal, thus improving the grade. The field can best be described by dividing it into two areas: the Southern area, lying to the south of the town of Princeton, where most of the mining has been done; and the Northern area, to the north of Princeton, where very little development has taken place.

Jan 1, 1947

By C. Zhou, B. Whisner, J. Carr

Proximity Detection Systems (PDSs) are used in the mining industry for protecting mine workers from striking, pinning, and crushing injuries when they work in close proximity to heavy machines such as continuous mining machines (CMMs). Currently all Mine Safety and Health Administration (MSHA) approved PDSs are magnetic field based systems which can be influenced by the presence of wire mesh that is commonly used for supporting roof and ribs in underground coal m ines. In this paper, researchers at the National Institute for Occupational Safety and Health (NIOSH) characterize the influence of the mesh on the performance of magnetic PDSs by measuring the magnetic field difference around a CMM caused by the presence of the mesh. The results show that the magnetic fields are generally enhanced by the mesh which causes the PDS detection zones to be increased correspondingly. It was discovered that the fields around the joints of two mesh sections have the greatest enhancement and thus deserve more attention. In addition, it is found that the presence of mesh can also cause a variation in the generator current. The influence of mesh is characterized by the change in the generator current with respect to the distance between the generator and the mesh. It was found that the generator current change caused by the mesh can be significant (on the order of ten) when the mesh is extremely close to the generator (e.g, less than 1 cm) and is negligible when mesh is relatively far (greater than 0.15 m). The findings in this paper can be used to develop guidelines and best practices to mitigate the influence of mesh on PDSs. INTRODUCTION The Mine Safety and Health Administration (MSHA) requires operators of underground coal mines to equip place-changing continuous mining machines (CMMs) with proximity detection systems (PDSs) to protect mine workers from striking, pinning and crushing injuries when they work around these heavy machines. Although a variety of technologies can be implemented for proximity detection, the magnetic-field-based PDS that was originally developed at the National Institute for Occupational Safety and Health (NIOSH) has shown great effectiveness in challenging mining environments and currently all MSHA-approved PDSs are magnetic-field-based systems. As shown in Figure 1, a magnetic PDS typically includes two major components----the magnetic field generator and the Miner Wearable Component (MWC). Magnetic fields are generated by injecting a high electric current into a ferrite-rod antenna sealed in the generator. The magnetic field strength detected by an MWC varies with the distance between the MWC and the generator. In a typical PDS, multiple generators are mounted on different locations of the machine. The relative location/zone of an MWC is determined based on the field strengths from different generators picked by the MWC. Ideally, for a PDS to work properly in the underground, the magnetic fields generated by the different generators should be stable and not vary with the environment, as the system would interpret any variation of the magnetic field as a result of the distance change between the machine and the miner wearing the MWC. In reality, however, this is not always the case since magnetic fields can be altered by a number of environmental factors such as the presence of steel wire mesh that has been widely used in underground coal mines for supporting roof and ribs In this paper, the influence of mesh on the PDS performance is investigated and the magnetic field change caused by the mesh is measured.

Jan 1, 2019

Laboratory testwork was carried out on an overall orebody composite, of 2.9 per cent Cu and 4.2 per cent Zn, prepared from drill core taken from the Currawong fine-grained, copper-zinc massive sulphide deposit near Benambra in Victoria. While 90 per cent of the copper was readily recovered in a concentrate of 20 per cent Cu, after grinding to 95 per cent passing 38 microns, zinc responded poorly to conventional flowsheet/reagent regimes. Experience elsewhere with the use of reverse cleaning, to separate pyrite from sphalerite, led to a series of tests in which better (but still modest)metallurgical results were obtained. The best result was a zinc recovery of 55 per cent in a concentrate of 50.5 per cent Zn. The major loss of zinc occurred in the reverse cleaning stage where the unit recovery of zinc was similar to pilot plant results achieved at Mount Isa Mines on similar feedstock. Diagnostic mineralogy suggested that an overall zinc recovery of 70 per cent was probably the practical upper limit, at a 50 per cent Zn grade.

Jan 1, 1999

By Z. T. Bieniawski

Geomechanics signifies the science and engineering of soil and rock materials and of rock masses. It is a field of professional practice and research that draws heavily on the elements of soil and rock mechanics. Geomechanics contributes to a number of disciplines: mining engineering, civil engineering, geological engineering, petroleum and natural gas engineering, and engineering geology (including the elements of geohydrology and geophysics). These disciplines are involved in the design and construction of such projects as mines, tunnels, foundations for structures, excavated rock slopes, dams, shafts, boreholes, oil reservoir wells, underground storage facilities for oil and gas, and hazardous waste repositories. Geomechanics allows us to improve both our environment and our quality of life. In the context of this Handbook, the scope of geomechanics is discussed mainly from the point of view of applications to mining engineering. However, the coverage of the subject mate¬rial is so comprehensive that it is relevant to other disciplines as well. Section 10 covers the field of geomechanics in a structured fashion, beginning with the fundamental principles and leading into practical applications in mining engineering. Throughout the treatment of the subject, knowledge of geologic conditions is assumed since this is discussed in other sections of the Handbook. An important feature of this section is a series of practical examples illustrating the various aspects of geomechanics. Since geomechanics is concerned with both soil and rock mechanics, Chapter 10.1 introduces the fundamentals of soil

Jan 1, 2008

By D. Harrington

The record of fatalities from mine explosions in the United States during the fiscal years 1934 to 1937 wars the best in the history of the mining industry; that for the fiscal year 1939, however, is not so favorable, since nearly as many men (170) were killed by explosions in 1938 as were killed during all of the previous 4 years (182). In spite of the large increase in fatalities from explosions during 1938, the average for the past 5 year period (70.4) is less than one-half the average (13) of the preceding 5 year period. The reasons for the large increase in the number of explosion fatalities during the 7 past year as compared with the previous 4 year are not entirely clear; it is: evident, however, that in some instances there has been laxity in the enforcement of State minim laws, and also that come of our coal-mining people, including workers and operating officials, have failed to carry out tine known precautionary measures to prevent explosions.

Jan 1, 1939