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By Charles V. Riley

While the late 1960's are known as the years of the public recognition of impending environmental crises, the 1970's will be known as the decade of public concern for improving the quality of that environment. One of the present major environmental concerns is the temporary disturbance resulting from coal surface or open cast mining. To realize that this concern will continue in the future, one need only observe the daily news media. Increasing energy demands in the U.S., a doubling of electrical power consumption each decade during the present century, and the projected needs for the remainder of the century are indica¬tions that coal surface mining as a major extractive industry will continue. Coal and lignite, prime energy resources and extremely abundant in these United States, in the face of seemingly limited gas, oil and uranium reserves, are both destined for expanded future use. Presently some extremely serious techno-logical and environmental problems are associated with the develop¬ment and use of nuclear power. It is true that the extraction and use of coal as an energy fuel poses disruptive problems for the environment, but the solutions to many of the problems are known or can be solved within a reasonable time framework. Certainly our national well-being and continued survival, as a free nation within the world community, automatically dictate the continued use of the coal resource for energy. Concurrently, those engaged in coal surface mining, with the temporary disturbance of the land and water resources, must also realistically conclude that public concern for maintaining and improving the quality of the environment will not diminish. Although as ecological, economic, social and aesthetic elements

Jan 1, 1972

By Tania Schmid, Marco Portal Valdivia, Sandra Nowosad

Today’s mining industry faces rapid transformation driven by automation, climate responsibility, and ESG demands, requiring more than technical expertise. Future mining engineers must blend engineering excellence with key human skills such as communication, leadership, resilience, empathy, adaptation to change, curiosity and lifelong learning. Based on two recent surveys, one to senior leaders with over ten years of experience in the mining industry and a second, focused on understanding the perceptions of young professionals, this paper explores which skills become core competencies by 2030 for navigating complexity, leading responsibly, and enabling sustainable transformation. Furthermore, it also examines how educational institutions can adopt strategies to foster the development of these critical skills, preparing future mining talent for evolving challenges.

Feb 22, 2026

By Alexander N. Winchell

"THE MICHIGAN COPPER DISTRICT.Location. The copper mines of Michigan are all in the north¬ern part of that state on the Keweenaw Peninsula, which extends from the (Michigan) mainland for about seventy miles northeast¬erly toward the middle of Lake Superior. The mines occur in a belt or zone occupying the central portion of the peninsula from end to end.. The most productive mines for many years past have been those located not far from the city of Houghton in' the central part of the zone, in a section extending about ten miles southwest of Houghton and fifteen miles northeast. The most important mines in order of.location, from the northeast to south¬west, are the following: Mohawk, Ahmeek, Allouez, North Kearsarge, Wolverine, South Kearsarge, Centennial, Calumet. and Hecla, Osceola, Franklin, Quincy, Hancock, Isle Royale, Superior, Baltic, Trimountain, and Champion. The first three named are in Keweenaw county and all of the others are in Houghton county. Still farther to the southwest are the Lake, Mass, Adventure, Michigan, Victoria, and White Pine mines. These are in Ontonagon county.History. The exploitation of these copper mines extends back into prehistoric times. There is little evidence that the American Indians carried on mining operations in this region in the period shortly before the advent of white men, but there is abundant evidence that the ancestors of the Indians, •or some earlier inhabitants of the region, carried on primitive mining operations. For example, Mr. S. O. Knapp, Agent of the Minne¬sota Mining Company, in the winter of 1847-48, made the first discovery of prehistoric mining. This event is described as fol ,lows by Foster and Whitney : Location: As shown on the accompanying map, the Mar-quette district extends from the region of Marquette on Lake Superior westward for about forty miles. The main basin of the district is only about three to six miles wide, but outlying areas which are commonly regarded as belonging to the same mining unit, make the north and south dimension of the district about twenty miles. The most productive portion of the area is in the vicinity of Negaunee and Ishpeming, .about ten miles from Mar¬quette, but important mines are found also all along the range as far west as Michigamme and also to the south in the fold known as the Republic Trough. Comparatively recent developments indicate that important ore bodies have been developed in the outlying Swanzy district about eighteen Miles nearly due south of Marquette.The Marquette Iron District.History: The first discovery of iron ore in the Lake Supe¬rior region was probably that made in 1844 near the site of Ne-gaunee by the government surveying party in charge of William A. Burt, sent out under the direction of Douglass Houghton. This surveying party was using a solar compass, invented by Mr. Burt, and noticed variations in the direction of the magnetic needle at various times and places, but. on the 19th of September, while running the east line of Township 47 North, Range 27 West, the needle varied from its normal position until it stood nearly at right angles thereto."

Jan 1, 1920

By T. C. Murray

An automatic control system was recently installed to insure the continuity of operation between the ship docking and ore handling facilities and the computerized conveyor-fed sintering plants and blast furnaces. Although the basic concept for material handling has not changed, many innovations including computer control have been implemented.

Jan 1, 1978

By Yuting Xue, Brijes Mishra

The relaxation test on sandstone specimens showed typical behavior in pre-failure region and stepwise behavior in the postfailure region. Overall, more significant stress relaxation occurred within the failed specimens than the intact ones. Numerical simulations were conducted with pre-defined failure plane and with Voronoi tessellation to visualize the relaxation behavior. The model with pre-defined failure plane showed the key role of failure plane and asperity in simulating the step-wise post-failure relaxation behavior. The inhomogeneous stress distribution within failed specimen and the viscous deformation of intact rocks induced high stress concentration at the asperities. The observed step-wise relaxation initiated from the failure of asperity. Furthermore, the simulations with Voronoi tessellation showed time-dependent fracture development during relaxation in post-failure region. The presence of fractures completely changed the stress distribution. Stress concentration occurred at the front area of fractures and at the interacting areas between fractures. During relaxation, fractures still developed with time and the sudden significant increase in the “damage” coincided with the acceleration of stress relaxation leading to step-wise relaxation. Finally, the results showed the possibility of using residual strength as the long-term strength of failed rock.

Jun 25, 2020

By W. M. Husslage

The permeability in the blast furnace shaft is adversely affected by low temperature reduction degradation of sinters. The fundamental cause is an expansion of the iron oxide phase resulting from reduction of hematite to magnetite. The present study showed that expansion behavior during the hematite / magnetite reduction step and the resulting microstructure are strongly influenced by the reduction temperature (viz. partial oxygen pressure), the reducing agent and the nature of the hematite. The reduction rate is of minor importance. A reduction mechanism is proposed, explaining the dilation behavior and the magnetite microstructure. The results can provide better insight into reduction degradation behavior.

Jan 1, 1998

By Y. Luo

Cuando se diseña y operan minas de carbón subterráneas con el método de cámaras y pilares, es siempre difícil obtener un buen equilibrio entre la prevención de subsidencia de la superficie y la obtención de un alto coeficiente de recuperación. En este trabajo se propone una metodología de diseño aplicando la teoría de arco de presión y se detallan los principios y modelos matemáticos involucrados. Se desarrolló un programa de computadora a fin de realizar el proceso de optimización del diseño y fue aplicado a la examinación de un caso documentado en el que había sucedido una falla masiva de un pilar en cascada sobre un área grande en una mina de carbón poco profunda. Los resultados indican que el método de diseño propuesto puede ser aplicado para prevenir la subsidencia y a la vez obtener un alto coeficiente de recuperación para operaciones mineras de cámara y pilares.

Jan 1, 2014

By M. Scaggs, L. R. Mendoza

"On January 9, 2014, a large chemical spill occurred on the bank of the Elk River near Charleston, WV. Within hours, the potable water supply for more than 300,000 people was contaminated, and the incident captured national headlines for weeks. Although the primary chemical, crude 4-methylcyclohexanemethanol, or MCHM, is deemed nonhazardous, the impacts of the spill are significant – with all stakeholders, including the public, members of industry, and relevant government agencies experiencing losses. This case highlights the need for a more proactive approach to environmental management, shifting from crisis control and remediation to crisis prevention and risk management. INTRODUCTION On the morning of January 9, 2014, approximately 10,000 gallons of crude 4-methylcyclohexanemethanol (MCHM) leaked from a 48,000-gallon storage tank sitting on the bank of the Elk River near Charleston, West Virginia (WVDEP, 2014; CSB, 2014). MCHM is a chemical commonly used in preparation of fine coal, and is deemed nonhazardous in terms of transportation and storage regulations and also toxicity (CDC, 2014a). Freedom Industries, Inc., a producer and vendor of specialty chemical products, had acquired the storage facility where the spill occurred from Etowah River Terminal, LLC just a few weeks prior in December 2013 (WVDEP, 2014; Freedom, 2005). The direct cause of the spill was ultimately determined to be two small holes in the base of the 76-year-old tank, which were created due to corrosion damage (Bauerlein & McWhirter, 2014). The spill site was located just over a mile upstream from the intake of a municipal water treatment facility operated by West Virginia American Water (WVAW), which serves a population of 300,000 across nine counties in central West Virginia (CDC, 2014a). In a matter of hours, the leaked MCHM made its way through the treatment facility and into the water of nearby homes and businesses, where its strong smell was noticed almost immediately. On the evening of the spill, WVAW concluded that its conventional treatment processes, which include carbon filters to remove a variety of contaminants from water, were not capable of fully removing the MCHM and a “Do Not Use” order was issued for all customers (WVAW, 2014a). With little information readily available regarding the potential human health effects of MCHM, the US Centers for Disease Control and Prevention (CDC) quickly issued an advisory ruling that set a maximum screening level of 1 ppm for safe drinking water (CDC, 2014a). Based on this recommendation, the “Do Not Use” order remained in effect for a total of eight days, until January 17, when the WVAW distribution water was confirmed to have MCHM concentrations below this level (WVAW, 2014a). However, due to the pungent odor of the chemical, its presence was still recognizable in the WVAW facility and in consumers’ tap water after the order was lifted (Manuel, 2014). Recent studies have shown that the chemical can be detected in water at concentrations as low as 0.55 ppb by individuals experienced in odor identification (Rosen et al., 2014); and even individuals with no such training can detect pure MCHM at just 7 ppb (WVTAP, 2014). The fact that this chemical can be sensed at such low levels – indeed far below those considered safe – undoubtedly added to growing public concern. In response to numerous complaints and demands, WVAW continued flushing the treatment facility and pipes until February 25 when MCHM levels were measured below 2 ppb (WVAWb, 2014), and eventually replaced the affected filter media (WVAWc, 2014)."

Jan 1, 2015

By E. A. Barrett, L. L. Rethi

Throughout all segments of the United States mining industry, 163 independent contractor employees were fatally injured between 1990 and 1997. Factors that contributed to these injuries were identified after reviewing descriptive information contained in Mine Safety and Health Administration fatality reports for each of the incidents. Thirty-three unique contributing factors were identified and multiple factors were noted for each fatality. Those most frequently discerned were "failure to follow `standard operating procedures"', (35% of the fatalities), "poor positioning of employee" (26% of the fatalities) and "failure to maintain equipment" (23% of the fatalities). Contributing factors were then associated with the accident and job classifications of the victims. Factors having the highest frequencies in the top five accident classifications where most fatalities occurred were as follows: powered haulage - "failure to maintain equipment"; machinery - "poor positioning of employee"; slip/fall of person - "inadequate fall protection" and "failure to wear safety line"; electrical - "equipment contact with power line"; and falling/rolling/sliding rock - "poor positioning of employee. " Among the job classifications in which most fatalities occurred, leading contributing factors were as follows: truck driver - "failure to follow standard operating procedures" and "poor positioning of employee"; laborer/utility man/pumper - "poor positioning of employee"; mechanic/ repairman and welder - "failure to follow standard operating procedures." Recommendations for utilizing contributing factor information as a basis for safety training are proposed. Training programs may be developed that inform independent contractor employees of factors which, in the past, have contributed to fatal injuries in their job classifications. Then, by combining this information with contributing factors identified in "related" accident classifications, a truly focused training intervention that addresses very specific workplace hazards may he developed.

Jan 1, 2002

By Zhongran Dai, Nan Hu, Jianhong Ma, Hui Zhang, Zhihua Zhong, Han Zhou, Feng Li, Yonggen Qiu, Yang Ding, Yingchun Yang, Dexin Ding

In the traditional chlorination roasting-water leaching-solvent extraction process for the extraction of rubidium-bearing ore, Rb leaching from the ore and calcium removing from the leachate are conducted separately, and this results in the complicated process and high energy consumption. In order to integrate the Rb leaching and calcium removing processes, Rb-bearing polymetallic ore was firstly treated by chlorination roasting, it was then leached in a micro-reactor with raffinate, and the calcium ions in the leachate were removed in the reactor as carbonate precipitates by passing CO2 at certain pressure into the reactor. The effects of raffinate alkalinity, CO2 pressure, and CO2 reaction time on Rb leaching rate and calcium removing rate were investigated. The experimental results show that when Rb-bearing polymetallic ore was leached for 90 min by stirring with raffinate with 1.125-mol/L alkalinity, and the pulp was made to react with CO2 at 0.8 MPa for 15 min, the Rb leaching rate and calcium removing rate amounted to 92% and 98.2%, respectively. This integrated process including Rb leaching from Rb-bearing polymetallic ore and calcium removing from leachate could simplify the process for the extraction of Rb-bearing ore and increase its economic benefits.

Sep 27, 2023

By Harrison R. Cooper

Approximately 40 concentrators throughout the world have successfully adopted computer control for flotation circuit operation since 1969. Successful use of flotation control, gaining up to 2% efficiencies, has largely derived from effective employment of on-stream slurry analyzers and integration of key measurement data through digital processors. Requirements for reliable measurement have also led to improved functional reliability in magnetic flow meters, pH, reagent feed, and other key elements. Methods used in computer control of flotation will be reviewed and variations in operating philosophies will be described with reference to the approaches taken to flotation automation.

Jan 1, 1979

By Ronald B. DeDiemar

It is generally held that cone crusher application technology is strictly an art and thus subject to the vagaries of emphirical and/or trial and error judgments. While this is basically true, certain factors have been identified which, when properly defined, can significantly reduce the element of chance. This paper will bring out these factors as well as pointing out other technologies available to predict and/or analyze cone crusher performance.

Jan 1, 1977

By Hossein Ghaedi, Hadi Fattahi

Despite the significant role of coal in the economic progress of nations, the occupational and health risks associated with its mining pose a major concern for industry stakeholders. The occurrence of roof collapses in coal mines remains a critical factor leading to substantial loss of life and financial damages for miners. Therefore, accurately predicting the roof fall rate (RFR) holds paramount importance. However, the uncertainty surrounding rock parameters in mines hinders the application of conventional methods to assess roof collapse rates in coal mines. To tackle the challenges associated with predicting roof fall rates in underground coal mines, this study proposes a novel solution by leveraging the Rock Engineering System (RES) method. The investigation is grounded in a dataset comprising 109 data points, encompassing crucial input parameters like depth of cover (DOF), primary roof support (PRSUP), intersection diagonal span (IS), mining height (MH), and coal mine roof rating (CMRR). In the model construction phase, 80% of the data (87 points) were utilized to build the RES model. A critical aspect of this study involves the evaluation of the RES model’s performance against alternative regression techniques, namely linear, power, exponential, polynomial, and logarithmic regression. This comparison was executed using the remaining 24 data points (20% of the dataset) for rigorous evaluation. Employing key statistical metrics such as mean square error (MSE), root mean square error (RMSE), and squared correlation coefficient (R2), the study systematically demonstrated the superior accuracy of the RES-based method compared to other approaches. In conclusion, the outcomes strongly support the efficacy of the RES method in predicting roof fall rates, not only in the specific case studied but also indicating promise for its application in other underground coal projects. This underscores the potential of the RES method as a reliable and versatile tool for forecasting roof fall rates in the complex and critical context of underground coal mining.

Mar 19, 2024

By A. M. Gaudin

A new method of measuring the viscosity of unstable suspensions has been developed, using a Heinz viscometer. The technique was applied to kaolin-water suspensions. Spreads in viscosity with lime additive were measured.

Jan 1, 1962

By Stanley N. Watowich

Recently the petroleum market has made us aware that we are indeed global natural resource consumers, and as such, we have become captive to fundamental global resource economics and their attendant vagaries. Global resource supply problems are as old as civilization and mineral exploration one of its important catalysts. On the basis of natural resources empires have been expanded and new frontiers have been developed. Global consumption and production might even be viewed idealistically as a system dedicated to optimizing distribution to the consumer. However, this is not the case. Political instability and increased government polarization make dependency on a global market somewhat insecure. The U.S. must evaluate its domestic mineral re- sources on the basis that all metals are critical and that dependency on even the common and base metals may ultimately weaken our domestic economy and our potential international relationships and could cause critical weaknesses as demonstrated by the petroleum problem. This paper evaluates specifically the Duluth Gabbro Complex, of Northeastern Minnesota, (figure l), as a potential resource of critical and strategic metals. First, a chronology of some of the early exploration, will be followed by more recent intensive company studies and preliminary evaluations of economic feasibility. Lastly, metallurgical data, on some optimum conceptual mining plans will allow metal production data to be compared with an estimate of U.S. domestic needs in 1990. The purpose of this paper is to put into focus the difficulty of converting resources into vitally needed reserves.

Jan 1, 1981

By S. S. Pathak, S. Mishra, M. H. Tyeb, A. K. Majumder

Roping in hydrocyclones is a well-known phenomenon in mining and mineral industries which put serious restrictions on their continuous and maintenance free operation. Roping is mostly observed in association with high underflow solid concentrations which can be attributed to higher fraction of solids reporting to the underflow or the feed solid concentration itself being higher. This paper proposes a newly designed spigot with a truncated conical geometry which can allow for a rope-free discharge at higher feed solid concentrations. The experimental observations revealed that in the operation of a 50.8-mm-diameter hydrocyclone, roping ensued at 10% to 12.5% (wt%) feed solid concentration depending on feed inlet pressure for the cylindrical spigot, whereas with the modified spigot, rope free discharge was attained even at 25% (wt%) feed solid concentration.

Jan 8, 2022

By B. Ballard

Engineers at a West Virginia coal preparation plant owned by one of the nation's largest coal producers sought a fire suppression system for the plant's MCC and cable spreading rooms. Officials considered the traditional options of water-based sprinklers, dry chemical, and clean agent systems; however, each of those options presented challenges. Sprinklers can damage electrical equipment, proper delivery of the agent and adequate coverage/protection can be an issue with dry chemical systems, and clean agent systems require room integrity. An alternative to traditional systems was discovered in the Victaulic Vortex Fire Suppression System. The first hybrid inert gas/water mist system (FM 5580), Vortex adequately addressed these concerns. The system, which deploys a high-velocity, low-pressure mixture of water and nitrogen, is not damaging to electrical equipment and extinguishes fires in open, ventilated areas. This is one of the first installations of the Vortex system in a prep plant, and is a compelling example of how new technology can overcome the challenges of traditional technologies. The paper will detail plant specs, situation, and system evaluation, selection, and configuration.

Feb 23, 2014

By Francis Martino

Just as coal producing mines are faced with various handicaps which control the quantity of coal produced and sold, the subsequent user of that product is faced with parameters that impact the optimum utilization of coal. Traditionally, the industry focused on the quantity of mineable coal in a reserve. The mine planning development was primarily concerned with two important criteria: (1) safety and (2) the productive efficiency in a quest to produce the lowest cost coal.

Jan 1, 1982

By B. A. Ashley

Rosebud Mining Co. (RMC) is based in Kittanning, PA. As of October 2013, it operated 24 active underground mines in Pennsylvania and Ohio. RMC?s Tracy Lynne Mine is located approximately 5 km (3 miles) east of Apollo, PA, (approximately 48 km or 30 miles northeast of Pittsburgh, PA) and mines the Lower Kittanning coal seam. The coal seam averages approximately 1.1 m (45 in.) thick and is of steam coal market quality. The mine is a single unit operation. Coal is mined using a continuous mining machine and is transported from the face to the conveyor belt using a continuous haulage system. Typical ventilation in the mine consists of an exhausting fan that draws air through isolated intake, belt and return air courses (Fig. 1).

By Irina Chernyshova, Erik Larsen, Hanumantha Rao Kota, Vladislav Slabov, Garima Jain

The mining industry faces pressure to provide metals for the green digital shift using sustainable technologies. This study evaluates biosurfactants as collectors for ultrafine and coarser particles of hematite and malachite, aiming to improve the flotation of ultrafine particles.

Jun 1, 2023