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Exploration of new resources and development of new equipment and designs are an ever changing facet of mining. New equipment to handle specialized operations is being developed and new techniques for its use explored. One such system is reviewed. Another is a potential system for handling the thinner stray coal seams between the more profitable thick seams. The availability of federal coal leases in the West is reviewed and current planning discussed. Gulf Coast lignites have been of much interest in recent months and are overviewed.

Jan 1, 1979

By Mirko Martini, Marcelo Benaglia, Andrea Codalli

Riachuelo Lot 3 forms part of a sanitation programme being implemented in Argentina to relieve the Riachuelo river basin from its current contamination. The programme, by far the most important in its kind in the country during the last decades, will expand the sewage capacity of Buenos Aires and will benefit an area of 4.3 millions inhabitants by intercepting a number of waste water discharges and conveying them to a new treatment plant prior to final discharge into the Rio de la Plata. The project foresees amongst other works the construction of an onshore 48 m deep shaft at the outlet of the treatment plant plus a 4,3 m inner diameter outfall tunnel of 12 km length. The last 1.5 km of the alignment is fitted with 34 vertical risers jacked from inside the tunnel to allow the discharge and dilution of the treated effluent into the Rio de la Plata. This paper describes the peculiarities and challenges, both in terms of design and in terms of construction, of the outfall tunnel, which was entirely bored under the Rio de la Plata using a 5.2 m cut diameter Tunnel Boring Machine (TBM). On one hand, the tunnel segmental lining was designed to work in tension during the system flow rate peaks while on the other the tunnel excavation faced a variety of complex conditions, such as crossing water bearing permeable soft ground formations and advancing at face pressures in excess of 3,5 bars for the entire route.

Jun 13, 2021

By William L. Husk

Stockpiles have always been a necessary part of coal mining except, perhaps, when a person was mining only for the needs of his family from a seam on his home place or coal mined for the use of a small hamlet and carried to each man's house as it was mined. Then it may have been stockpiled at each man's place for several days or on the village common. Mining with this limited production required waste stockpiling. Stockpiling of the products of coal mining, both coal and waste material, has always been a necessity. Very little coal has ever been moved directly or immediately from the working face to the point of consumption and burned. It has always been expedient to stockpile the coal some- where and store the waste.

Jan 1, 1981

By William Gleason

"Caterpillar is the largest manufacturer of mining equipment in the world. In hundreds of surface mines around the globe, Caterpillar’s flagship 793 haul trucks can be found moving material for copper, coal, gold, iron ore and other mines. Likewise, its iconic yellow bulldozers are at mine sites the world over — the company recently announced the sale of its 40,000th large dozer. And since its acquisition of Bucyrus in 2011, Caterpillar has positioned itself to become a worldwide leader in the underground mining sector as well.But don’t think that the company is resting on its reputation. As evidence of its commitment to the global mining sector, as well as its confidence in the future of mining, Caterpillar invited mining trade press, including Mining Engineering, to its Tinaja Hills Training Center near Tucson, AZ in November to introduce the latest editions to its mining portfolio. The two-day event focused mostly on the newest electric drive haul trucks, the Cat 796 AC, which will operate in the 326-t (360-st) class, and the 798 AC in the 360 t (400 st) weight class.Caterpillar representatives also spoke about new offerings in the underground space as well as the newest version of the D11 large dozer.“It has been 10 years since we launched the F Series,” Jean Savage, Caterpillar’s vice president, surface mining and technology said. “Since then, we have been on a journey to serve our mining customers and we wanted to have trucks in every application. Today, we are launching two new trucks that will allow us to fill out our portfolio.”While Caterpillar previously offered the broadest range of off-highway haul trucks to the mining industry, it was noticeably absent from the 326-t (360- st) and 360-t (400-st) weight classes."

Dec 1, 2018

By Phil Shelton

What exactly does clean coal mean? Mining coal creates dust and releases methane gas. And burning coal liberates CO2 and emits particulates, including SO2 and NOx. Coal creates wastes that are often stored in unsightly and potentially dangerous slag heaps and lagoons. When clean coal technology is discussed, it sometimes seems that creating modern or ?ultra super critical? coal-fired power stations is presented as the main or even the only answer. However, there may be a more holistic approach. Using the energy potential of coal is always going to have environmental impacts. Some of these will be negative. But the need to secure future energy resources demands that society tackle these negative issues and find ways to minimize and offset them.

Jan 1, 2010

By William Gleason

"Modern society demands much more from the mining industry than just the raw materials it produces. In addition to providing copper, gold, coal and other minerals that make society function, the industry must conduct its operations in a safe and environmentally sustainable manner. This includes the equipment used and the engines that power the machines.In the United States, Tier 4 diesel engine standards that were set by the U.S. Environmental Protection Agency (EPA) are the strictest emissions requirement for off-highway diesel engines. This requirement regulates the amount of particulate matter (PM) and nitrogen oxides (NOx) that can be emitted from an off-highway diesel engine. In Europe, the Euro V standards are driving technology advancement in the sector.The European Euro V standards are required for new equipment manufactured beginning in January 2019. U.S. Tier 4 standards for heavy-duty off-road engines came into effect with model-year 2014 vehicles and equipment. China 6 standards come into effect in July 2020. India’s Bharat Stage VI standards will take full effect in 2020, and the phase-in of BSVIcompliant clean fuels began in April 2018.Caterpillar, Cummins and MTU are three of the leading manufacturers of engines for the mining sector. Each company is working toward creating efficient engines that can function in the often harsh environments found at openpit and underground mines around the world. In short, society is placing demands that are challenging engine manufacturers to deliver a product that can do more work while consuming less fuel and emitting fewer emissions.Technologies range from selective catalytic reduction (SCR) and diesel particulate filters (DPFs) to other engine strategies and emissions control technologies, which deliver near-zero black carbon and nitrogen oxide emissions, and lower greenhouse gas emissions. Caterpillar’s investmentCaterpillar, the world’s largest producer of mining equipment and mining engines, has been at the forefront of the changing demands placed on the industry and has remained on the cutting edge of engine development over the years, thanks to its investments in the sector.“Caterpillar made the choice to fund major engine and machine development work — even during a deep trough in the mining industry — so that Cat machines would meet Tier 4/EU Stage 5 mandated compliance dates of Jan. 1, 2018 / Jan. 1, 2019, respectively. For Caterpillar, these efforts enabled our mining trucks to provide improved engine component life to help our customers’ total cost of ownership (TCO) and produce a neutral TCO compared to our Tier 2 products,” said Jeff Castleman, new product introduction manager, large mining trucks for Caterpillar."

Aug 1, 2019

By Daniel M. Flanagan

"Editor’s note: Each year, Mining Engineering features an industrial minerals review. Several people put in a fair amount of time in developing the material for this issue, all the while doing their own jobs. Thank you to the industrial minerals annual review editor, to the Industrial Minerals & Aggregates Division technical committee chair and vice chairs, and to the authors of the individual commodity profiles. Jim Norman, member SME, of Tetra Tech, is the industrial minerals annual review editor.Joe Garska, member SME, of Imerys, is chair of the Industrial Minerals &Aggregates Division’s Technical Committee.The technical committee vice chairs include:• Hyunjung Kim, member SME, of Chonbuk National University, agricultural materials.• Xihui Lin, member SME, of Kemira, ceramics and refractory materials.• Nikhil Gupta, member SME, of Virginia Tech, chemical raw materials.• Adam Rodriquez, member SME, of Penn State, construction aggregates.• LeDeana Roberts, member SME, of Imerys, fillers and pigments.• Harsha Kolla, member SME, of ChemEOR, sorbents, filters and process aids.• Edgar Blanco, member SME, of FLSmidth, specialty minerals.Their help makes possible this July industrial minerals issue. On behalf of ME readers, the editors thank them.During the past 25 years, U.S. ball clay production (the quantity sold or used by domestic producers) increased from 788 kt (869,000 st) in 1990 to an alltime high of 1.31 Mt (1.44 million st) in 2003 (Fig. 1). Housing construction within the United States, a leading market for ball clay-based ceramics and sanitaryware, began to decline in 2005, which resulted in a considerable decrease in sales of ball clay that continued through the 2008-2009 economic recession. After bottoming out at 831 kt (916,000 st) in 2009, ball clay production steadily increased through 2015 (Fig. 1). Estimated sales in 2015 were 36 percent higher than those in 1990 and 18 percent lower than those in 2003.Four companies (H.C. Spinks Clay Co., Imerys S.A., Old Hickory Clay Co., and Unimin Corp.), mined ball clay in five states during 2015. An estimated 1.7 Mt (1.18 million st) of ball clay valued at an estimated $47.5 million was sold or used by U.S. producers, a 4-percent increase from 1.03 Mt (1.14 million st) valued at $45.2 million in 2014. Approximately 65 percent of total ball clay production was air-float, 25 percent was crude or shredded and 10 percent was water-slurried"

Jul 1, 2016

"With millions of dollars and thousands of lives at stake, the Iron Ore Company of Canada (IOC) turned to a private wireless network for help.IOC needed a network that possessed the ability to adapt to changes in a nanosecond and to function seamlessly in the most rugged of environments.Canada’s largest iron ore producer required a private wireless network powerful enough to support all mine applications and deliver all data to one central point — without any existing cellular/3G/Wi-Fi coverage.Operations at IOC, a leading global supplier of iron pellets, involved dispatch, drill management and equipment monitoring, pump control and remote video that must service three distinct pits. Due to its setup, the facility does not offer a great deal of flexibility for transmitting signals.IOC serves a robust customer base made up of North American, European and Asian steel producers. It also employs nearly 1,900 people. Catastrophic death and destruction are two very real potential consequences of system communication failure.Technology for tough terrainKinetic mesh technology was born in the wake of the 9/11 terrorist attacks on the United States, one of the most high-stakes emergency situations in U.S. history. The failure of the communications infrastructure on a massive scale that day underscored the need for networking technologies that could provide service even in the most chaotic of conditions.Kinetic mesh networks allow organizations to deploy networks at sites where communications infrastructure has been compromised, as well as quickly establish networks in places where they did not previously exist. Kinetic mesh networks have also demonstrated a better ability to adapt to network changes on-the-fly versus other types of networking technologies."

Jan 1, 2015

By D. R. McConnell

The seafloor in the US Pacific OCS and EEZ is enriched to varying degrees in critical and economically important minerals such as nickel, manganese, cobalt, copper, zinc, REY (rare earth elements plus yttrium), titanium, vanadium, antimony, gold, and silver. These mineral deposits take the form of polymetallic nodules on the seabed, cobalt rich ferromanganese crusts on seamounts and ridges swept clean of sediment accumulation, and seafloor massive sulfides formed by hydrothermal systems at geologic plate spreading centers and volcanic margins. Each of these mineral deposits form on or near the deep ocean seafloor where water depths are typically 4000 m to 5500 m and on the seamounts and volcanic arcs that rise from these depths. Commercial interest in deep sea mineral deposits and the potential for collecting or mining them began in earnest in the 1970s but has been heightened in the last 20 years as the international framework for developing these minerals in International Waters has matured that has coincided with forecasted rapid rising demand for minerals to supply energy and manufacturing needs for the green economy. Compilation reports published by academia, government, and private companies are reviewed to assemble data and assess the prospects for deep sea marine minerals in the US Pacific OCS and EEZ. Key compilations were made by the Circum-Pacific Council and USGS in the 1980s and 1990s. These, together with recent (2023) efforts by USGS to compile geochemical data from USGS affiliated marine research sampling cruises from the 1980s and 1990s, historical data maintained by NOAA National Centers for Environmental Information (NCEI), and recent publicly disclosed results from ISA contractors are used to inform the known occurrence and prospectivity for polymetallic nodules, cobalt-rich ferromanganese crusts, and seafloor massive sulfides in the US Pacific OCS and EEZ.

Feb 22, 2026

By Steven W. Hunt, Glen R. Frank

Assessment of abrasivity and cutter life are necessary to properly manage risks when tunneling in mixed face ground which includes ground with cobbles and boulders. Maximizing cutter life requires: (1) abrasivity and strength parameters for soil matrix and rock clasts, (2) methods of combining both, (3) proper selection of cutters and (4) modified TBM operation including use of boulder detection methods from the TBM to help make operation decisions. This paper presents approaches for addressing these factors sufficiently to improve tunneling success in mixed-face and cobbly-bouldery ground. Current laboratory abrasivity testing will be assessed along with equivalent quartz content correlations to soil matrix and rock clast abrasivity. New approaches to combining abrasivity testing of both the soil matrix and rock clasts for various cobble and boulder volume ratios will be suggested to estimate cutter life and intervention intervals. Methods for detecting boulders and using detection data to modify TBM operations to minimize boulder impacts are provided.

Jun 13, 2021

By E. Lee Bray

"Editor’s note: The editors thank those who make this annual issue possible. A special thank you goes out to the Industrial Minerals Annual Review editor, to the Industrial Minerals & Aggregates Division Technical Committee chair and vice chairs, and to the authors of the individual commodity profiles.Jim Norman, member SME, of Tetra Tech Geo, is the industrial minerals annual review editor. Edgar Blanco, member SME, of Freeport- McMoRan, is chair of the Industrial Minerals &Aggregates Division’s Technical Committee.The technical committee vice chairs include:• NickTushar Gupta and Sallie Gaillard, of the USGS, members SME, agricultural materials.• Abhishek Choudhuryand Xihui Yin, members SME, of Montana Tech and Kemira, repectively, ceramic and refractory materials.• Bobbi Strange and Riddhika Jain, members SME, of Outotec, Martin Marietta and Outotec, respectively, chemical raw materials.• Snehamoy Chatterjee, Alyssa Kendir and Alind Chandra, members SME, of BMT, Universityof Kentucky and Michigan Tech, respectively,construction aggregates.• Subham Verma, Gauran Soni and Freddy Sime, members SME, fillers and pigments.• Kaiwu Huang, Thomas Hilderbrand and Ricardo Santander members SME, of Virginia Tech, Thiele Kaolin and Carbo Ceramics, respectively, sorbents, filters and process aids.• Rhaghay Dubey and William Rapier, members SME, of Outotec and a consultant, respectively, specialty minerals.On behalf of ME readers, the editors thankTwo U.S. alumina refineries produced an estimated 1.5 Mt (1.65 million st) of alumina from imported bauxite in the United States in 2018. The 500-kt/a (550,000-stpy) refinery in Burnside, LA, owned by Almatis Inc. produced specialty alumina used in the abrasives, ceramics, chemical and refractory industries. The 1.2-Mt/a (1.32 million-stpy) refinery in Gramercy, LA, owned by Noranda Alumina LLC produced alumina mostly for use in aluminum smelters but also produced specialty alumina. An upgrade project at the Gramercy refinery to convert 200 kt/a (220,000 stpy) of capacity to produce more profitable specialty alumina was completed in the first half of 2018, and another project to increase capacity was started but a completion schedule was not available. The amount of new capacity was not disclosed, but it would be used to produce nonmetallurgical grade alumina. The 2.3-Mt/a (2.5 million-stpy) refinery in Point Comfort, TX, which was temporarily shut down in March 2016, remained closed throughout the year."

Jul 1, 2019

By Eric Jacobs

"Building and operating tunnels has been a highstakes endeavor in terms of costs, complexity, safety and impact on contractors, owners and the public for a long time. There are many variables that need to be closely monitored and managed to construct a tunnel on-time, on-budget and safely. Once built, there are also many elements that need to be monitored and managed to operate a tunnel safely and efficiently.Fundamentally, the risks to the safe and efficient construction and operation of a tunnel are a function of the degree of harm and the likelihood of the harm occurring. From a cyber security perspective, risk assessments used to inform decision makers and support risk responses are typically based on identification of relevant threats; internal and external vulnerabilities; the impact that may occur given the potential for threats to exploit vulnerabilities and the likelihood that harm will occur. This article focuses on creating awareness of vulnerabilities associated with technology used in tunnel construction and operation and some of the challenges associated with remediation of these vulnerabilities. As we all know, technology has been evolving at an accelerating pace and infiltrating every aspect of our lives in new and often exciting ways. In the world of tunneling, sensors and systems that provide position and time have become accurate, rugged and cost-effective enough to come out of the research labs and into the equipment and systems used every day. There are many opportunities to employ connected computing devices and sensors to costeffectively capture, integrate and analyze key data with minimal latency to manage risk better, improve safety and avoid surprises."

Jun 1, 2019

By Earl Parker

The mining/mineral processing industry constantly faces the challenges of handling tons of material in a variety of processes such as crushing, milling, drying, belt transfer and loadout. These processes result in the production of high volumes of dust. A variety of dust detection and collection equipment is needed to properly manage these emissions to remain compliant with stringent air quality and safety requirements. Dust monitoring and bag leak detection can provide ways to reduce air pollutants, make work environments safer and remain compliant with requirements from the U.S. Environmental Protection Agency (EPA), U.S. Mine Safety and Health Administration (MSHA) and U.S. Occupational Safety and Health Administration (OSHA). There are several approaches to monitoring particulate emissions from dust collection equipment. These can include visual inspections, differential pressure gauges or bag leak detection systems. Bag leak detection and monitoring systems can be optical, light based or electrostatic/triboelectric. Recent developments have advanced the efficiency and reliability of electrostatic/triboelectric style monitors. New technological improvements have been developed that are based upon the principal of unifying dc (impaction) and ac (induction) signals and incorporating other proprietary circuit innovations. This higher signal resolution technology results in a more robust and stable measurement for detecting the presence of particulate in a dust collector emission duct or a flow process pipe.

One of the critical challenges facing the mining industry ? and not just in the United States ? is the looming labor shortage. A significant percentage of the industry?s professional workforce is, well, getting old, and many will be retiring in the next 10 years or so. This is not a new issue to the industry. It has been discussed at various industry meetings and conferences for many years. How does mining, with its largely negative public image, attract young people to mining schools? And, equally important, who is going to teach them? Mining schools, what?s left of them in the United States, are beginning to lose qualified faculty to retirements, and no one is available to replace them. SME addressed this issue during the keynote session at its annual meeting in February in Denver, CO. This year?s theme was ?Mining: It?s About the People.? Despite a blizzard that blanketed the city on the day most attendees were to have arrived, the meeting still attracted a record 7,202 people. And the accompanying exhibit sold 822 booths, also a record. The U.S. Department of Energy?s National Energy Technology Laboratory contracted with the National Academies? National Research Council to complete a study concerning the availability of skilled workers to meet the energy and mineral security requirements for the United States. The National Research Council, in turn, asked SME to collect and analyze workforce trends in these industries. The result of SME?s analysis is the report ?Emerging Workforce Trends in the U.S. Energy and Minerals Industries.? It is available on the SME website, www.smenet.org. Click on Government Affairs. While the report did not paint a completely dismal picture, there were some disturbing results. It concluded that within 20 years there will not be a sufficient number of skilled professionals to satisfy the labor demand. That said, the report said that most of those positions would likely be filled. However, the U.S. mining will go through a period of time when the workforce will be made up of very young and senior workers.

Jun 1, 2013

It had been more than a decade since this many booths were occupied at an SME Annual Meeting, but at the 2010 meeting in Phoenix, AZ 630 booths were sold to 470 vendors from the entire spectrum of the mining and minerals industry. Exhibitors such as Metso, FLSmidth, West-Tech, ABB, NIOSH, Eriez and Resource West took their usual prominent places on the exhibit floor and were joined by newcomers such as tunnel boring machine manufacturer Herrenknecht AG, Frontier Kemper, the International Society of Explosive Engineers and more than 100 other first-time exhibitors. On the floor, one could find everything from a new pair of boots to a new career in the recruitment pavilion where some of the biggest companies in mining (Barrick Gold, Freeport-McMoRan, Newmont Mining, etc..) set up shop. The following is a look at some of the companies and products that were on display at the 2010 meeting. For information about displaying at the 2011 annual meeting in Denver, CO, Feb. 27 to March 2, contact exhibits@smenet.org.

May 1, 2010

By Trevor R. Ellis

Minerals appraisers/valuers often find great difficulty in attempting to employ the sales comparison approach to the market value appraisal of development and operating stage mineral properties. An important factor generally overlooked is a comparison of net operating income (NOI) margins on a per-unit-of-production basis between mineral properties, whether these be demonstrated or forecast margins. NOI margins can vary greatly between mines or quarries that are producing similar products. Ultimately, the expected NOI margin determines what a buyer is willing to pay for an income-producing property. Here, common criticisms of the sales comparison approach by mineral appraisers are introduced. These are counterbalanced by raising some issues in the way the inputs for the income approach are usually derived by minerals appraisers and by review of some conspicuous examples of the much-too-common misuse or abuse of the income approach in market value mineral appraisals. Example transaction analyses and sales comparison analyses are used to demonstrate the author?s methodology for adjusting units of resource in his transaction adjustment tables. The examples are used as the basis for a discussion of ways to employ adjustments for operating economics and many other factors, while warning against the potential for double counting. The conclusions include a recommendation that minerals appraisers attempt to apply at least two of the three valuation approaches when appraising the market or fair value of development and operating stage mineral properties, the two being the sales comparison and income approaches.

Jan 1, 2011

By Russell G. Shomperlen

Grinding mills in excess of 5 meter diameter and 3500 kilowatts per mesh are putting new demands on big gears. This paper returns to the basics of ring gear design beginning with the fundamental power formulas specified by AGMA. Specific emphasis is given to those elements in the rating equations which require closer attention as gear diameters and transmitted power increase. Strict process control in the manufacture of the gear blank is also stressed. Finally, the writer offers a guide to proper installation, lubrication and maintenance.

Jan 1, 1981

By Erik Sundström, Magnus Nygren

Having seen significant improvements to accident rates in the last 40 years, companies in the Swedish mining industry now show a greater focus on the development of safety cultures throughout their organisations and workplaces. However, there is a lack of research examining the different safety initiatives and strategies practiced in the industry today. This study explores the potential influence and consequences such initiatives may have on the development of safety cultures in the Swedish mining industry. Twelve interviews with experts on safety initiatives from four different Swedish mining organisations were conducted and analysed in a process based on qualitative thematic analysis to identify notable connections to safety culture development. The results of these interviews highlight proclivities in the implementation and use of safety initiatives such as subjects of focus, methods and desired effects. This enables the interpretation of the conceptualisation and methods for the development of safety culture in these organisations based on their approaches to safety development. We believe the results of this study can serve as support for discussions on safety culture development in the Swedish mining industry, and be of interest for international mining industries, in addition to approaches to research in this field. However, we also believe it is important to emphasise the opportunities to approach safety culture in mining from different perspectives than those common today.

Jul 19, 2023

By Alan K. Burton

Massive increases in the productive capability of open pit nines after World. War II were in a large part made possible by the introduction of ever larger trucks and the supply of a seemingly bottomless ocean of inexpensive and readily accessible oil. Over a period of about 25 years, a variety of technological developments permitted a tenfold truck payload increase, from about 32 tonnes (35 tons) to 320 tonnes (350 tons). There is no, doubt that this was a remarkable achievement resulting in impressive benefits of scale as well as the ability to control what would otherwise have become an intolerable traffic congestion problem in today's large open pit mines. It became fashionable and economically possible during this time to mine large quantities of low grade material and to tolerate very high stripping ratios. As tine has gone by and as easier to get at and higher grade deposits have been depleted, ore grades have tended to decline while stripping ratios have increased. The alternative to reduced revenues has been an ever increasing demand to step up production which in turn has led to a continuing demand for ever larger and larger trucks. While a larger truck has had the effect of reducing the cost of the operator per unit of material moved and of reducing traffic congestion, it has not specifically addressed the subject of fuel cost.

Jan 1, 1981

By Bruce Bryant

Silver ore was discovered at Aspen in 1879, but the district did not reach full production until 1888 after lawsuits were settled and railroads furnished less expensive transportation to the outside world. The boom years were 1888-92; production declined thereafter. From the middle 1920's until 1950, the Midnight mine in the Richmond Hill district furnished most of the output in the Aspen quadrangle. Since 1950, little mining has been done at Aspen. The metals produced were silver, lead and zinc. Native silver dissolved from the sulfide ores was redeposited by waters circulating as deep as 300 m below the land surface, resulting in great secondary enrichment of many of the deposits. Over 100 million ounces of silver were produced in the Aspen quadrangle. Low-grade lead-zinc deposits remain between the old workings locally, and data available suggest that primary ore below levels mined is also of low grade. The ore occurs in the Mississippian Leadville Limestone and the lower part of the Pennsylvanian Belden Formation in sites that were made favorable for deposition by a number of stratigraphic and structural factors.

Jan 1, 1982