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By Erik Marsh, Frederick C. Harris Jr., Javad Sattarvand, Joshua Dahl, Alireza Kamran Pishhesari

Based on the mine safety and health administration (MSHA)reports, mining truck accidents are among the significant causes of fatalities in the mining industry. The major causes of haulage accidents can be divided into non-driving and driving factors, such as truck-related sudden failures and operator performance. Numerous parameters affect trucks' safe operation, but situational awareness plays a significant role. Due to the distinct structure of mining trucks, making them efficient for mining purposes, the operator has a very limited field of view (FOV), making them prone to accidents resulting in losing lives. The cabin's position blocks the truck's right and rear sides, creating several blind points around it. Aiming to test/train the operator's awareness of the surrounding, a proximity detection system is developed through a multiplayer virtual reality (VR) application to investigate the human factor in equipment collisions. The operators were examined and monitored when asked to conduct what exactly happened in the Marigold mine truck accident without being aware of the scenario. After receiving sound, vibration, and visual alarm warnings, their reaction and performance were analyzed. The platform is developed using the Unity game engine for HTC VIVE virtual reality goggles. An Omni-direction treadmill and a motion simulator platform are utilized for the player and dump truck operators. Fifteen students were monitored when driving the dump truck receiving/not receiving proximity detection alarms. None of them repeated the accident when receiving proximity alarms. Also, they found the visual alarm the most comfortable while driving the truck.

Jun 25, 2023

By W. D. Elston, A. E. McLaughlin, G. B. Hampton, W. L. Barham, J. F. Murphy, W. H. Cundiff, J. W. Mulloy, R. G. Breuer, J. W. Shaffer

Introduction Alumina (aluminum oxide) is the material from which all the world's aluminum is produced. In the Western World, all the alumina is made from bauxite by the Bayer process. In the nearly 150 years since aluminum was first isolated by Oersted, the metal has grown from a laboratory curiosity to a position of major importance in the world's commerce. In terms of annual production rates aluminum is first among nonferrous metals. Oersted's discovery-reduction of aluminum chloride with potas¬sium amalgam-was improved on by Ste. Claire Deville, whose so¬dium amalgam reduction of aluminum chloride led to the commercial production of aluminum in France in 1855. Ste. Claire Deville's method prevailed until 1886 when Charles Martin Hall and Paul T. Heroult each invented a process for the production of aluminum by the electrolysis of alumina dissolved in molten cryolite. The inven¬tion by Karl Josef Bayer in 1888 of an economical process for making very pure aluminum oxide (alumina) from bauxite established the necessary link between known ores and the Hall-Heroult reduction process. Bayer's work completed the scientific base-the ore bauxite refined to alumina by the Bayer process (U.S. Patent No. 515,895), the alumina reduced to aluminum in the Hall-Heroult cell (U.S. Patent No. 400,766--upon which today's aluminum industry is founded. Small-scale production of aluminum in the U.S. began in 1888 utilizing the Hall cell. By 1903, bauxite properties and a Bayer process refining step had been incorporated into the production activities. On this base the aluminum industry in the U.S. has grown at an annual compounded rate of 15%. Since 1946 the annual growth rate has been 10%.1 The rapid growth of the industry is the result of many factors among which are the existence of widespread bauxite ore deposits; a sound and economic production technology; and the properties of the metal-lightness, strength, ductility, good electrical and heat con¬ductivity, and pleasing appearance, which lead to ever greater de¬mands for aluminum in an industrializing society. At the inception of the industry, the only market that could be found for aluminum was in the production of cooking utensils. How¬ ever, the rapidly accelerating industrial and technological development of the Western World soon created new needs for aluminum, and today aluminum is marketed in a broad range of industrial, commer¬cial, and consumer applications. The principal uses for aluminum are:' building and construction, 22%; transportation, 18%; electrical, 13%; packaging, 11%; consumer durables, 10%; machinery and equipment, 7%; other, 19%. The 1974 production of primary alumi¬num in the world was 14.5 million short tons, which at an approximate ingot price of 40¢ per lb puts a value of $11.6 billion on the industry product prior to fabrication. While aluminum is widely distributed in the earth's crust and is a major constituent of many rocks and soils, to date no method of extraction of aluminum from such nonbauxite material has been brought to commercial practice in the Western World. In the USSR alumina is produced by the complex processing of nepheline syenite, but elsewhere all commercial production of alumina is from bauxite. A brief discussion of recent developments and other processes for alumina is included in the subsection "Other Processes for Alumina," page 19-15. In early 1973, a major U.S. aluminum producer announced the successful development of processes for the production of aluminum from aluminum chloride. This achievement promises to exert a major influence on the future of the aluminum industry. In the initial com¬mercial application of this new technology, Bayer alumina will be chlorinated, and the aluminum chloride then reduced by electrolysis. Important claims for the new processes are lower energy requirements (one-third less than obtainable in Hall cells) and reduced labor costs. Capital costs are said to be no greater than for conventional plants. While the announced intention is to produce the aluminum chlo¬ride from Bayer process alumina, the new chloride reduction process will eliminate the other raw materials, carbon and fluorides, required by the conventional Hall cells. The electrodes in the chloride cell will not be consumed on the reduction process and the electrolyte will have, as the name indicates, a chloride rather than a fluoride base. 2. Bauxite Definition and Origin. Bauxite is a naturally occurring raw material composed principally of a mixture of one or more of the hy¬drated aluminum oxide minerals gibbsite (Al2O2 3H2O), boehmite (Al2O3 H2O), and diaspore (Al2O, - H2O), and impurities of silica, iron oxide, titania, and other various elements in trace amounts. It is an end or near-end product of chemical weathering. Depending on the amount of iron impurities, the color of bauxite varies from dark red and brown to pink to white. Some bauxite is finely divided, free digging earthy material, while other forms are dense and rocky, requiring explosives in mining. Many gradational forms exist. It is one of the most variable of mineral raw materials in chemical composition and physical appearance. It is generally believed that bauxite deposits resulted from intense chemical weathering of aluminum-bearing rocks or formations under tropical or subtropical conditions with alternating wet and dry sea¬sons. Topographic conditions were favorable for drainage and the in-situ accumulation of aluminum, iron, and titanium oxides. There was low to moderate topographic relief with a minimum of erosion during long quiet periods in earth history.2 The occurrence of bauxite is widespread and it has been found on all continents except Antarctica. Production was reported from 27 countries in 1974, at which time total world production was over 79 million metric tons. Of this production 76% was from seven coun¬tries-Australia, Jamaica, Surinam, Guinea, USSR, Guyana, and Greece-which ranked in that order of production. In Table 1 are shown typical compositions of bauxite from some

Jan 1, 1985

By J. F. Stenebråten, W. P. Johnson

Carbonaceous material (CM) from the Barrick Goldstrike Mines, NV, was characterized with respect to its gold sorption (preg-robbing) and gold recovery behavior. The breadth of graphite peaks measured by X-ray diffraction were used to calculate crystallite dimensions (002) of the CM. The (002) dimension was found to vary inversely with preg-robbing activity and directly with gold-recovery behavior, indicating that the degree of graphitization (maturation) experienced by the carbonaceous material is correlated with gold-loss during ore processing. The inverse correlation of preg-robbing activity was improved when percent preg-robbing was regressed against (002) crystallite size and carbon content. The (101) crystallite dimensions of all samples were calculated from laser Raman analysis, and were not found to correlate with preg-robbing behavior of the CM. BET surface area and micropore size distribution results were affected by grinding history, negating comparison of these characteristics between samples.

Jan 1, 2000

By R. S. C. Rogers

The present study examines the use of two vs. one stage of hydrocyclones in a pilot scale ball mill circuit. The approach used for doing this is based on computer simulation with mathematical models that explicitly account for the grinding mill/classification system interaction. Parameters for the ball mill model are obtained using a short-lived radioactive tracer method in open circuit tests of the study mill. The hydrocyclone model, based on the size selectivity concept, is developed and validated in standalone testing of the study hydrocyclones. Simulation procedures are validated through actual tests of the closed circuit grinding configurations of interest. Results of the evaluation indicate that two stages of hydrocyclones in the study circuit would improve classification, increase productivity and lead to more closely sized circuit products when compared to the conventional one stage hydrocyclone circuit. A computer simulation approach for comparing these circuit configurations in larger scale grinding circuits is also suggested.

Jan 1, 1981

The Longwall Strata Control and Maintenance System (LoSCoMS) is designed to monitor shield pressures in real-time from longwall faces and to provide on-line information related to underground strata behavior and longwall mining operation. The information includes shield pressure data with statistical analysis of setting, developing and final pressures, prediction of shield pressures for the following shift or day, etc. and maintenance data on the shields. The LoSCoMS has been installed and tested at Shoal Creek Mine operated by Drummond Company, Inc. The system is providing valuable information to mine operators for better understanding of underground behaviors. As a result, it has become an effective tool for minimizing ground control hazards and reducing out of seam material.

Jan 1, 1997

By R. O. Harma

Wet autogenous grinding is utilized in three iron ore concentrating plants operated by The Cleveland-Cliffs Iron Company (CCI). This paper will trace some of the development in converting from the use of metal grinding mill liners to the use of rubber and will update the current performance of rubber liners in these applications. The Cleveland-Cliffs Iron Company is a natural resources firm with major interests in iron ore mining and processing and oil and gas contract drilling. The company also has interests in oil shale, uranium, forest products, and Great Lakes shipping.

Jan 1, 1982

By Peter Schmäh

Pipe-jacked tunnels are considered for a large variety of applications from water and sewage, cable ducts to challenging pipeline crossings or landfall construction. In most cases, Slurry MTBMs are used to carry out these projects. Continuous further development of technological features for pipe jacking plays a key role to overcome feasibility limits and to meet increased project requirements. As tightened safety regulations in terms of accessibility and escape routes increasingly limit the options of small segment lining tunnels in the diameter range below 4 m, 13 feet, pipe jacking has partially taken over. During the last decades, a growing number of large-diameter and long-distance pipe jacking projects have been completed. Experienced contractors successfully use the technological capacity of the MTBM equipment. The machine and cutting wheel have to be designed according to the ground conditions. Bentonite lubrication and interjacking stations are key factors to keep push forces moderate. For long pipe jacking drives, a so-called push module can be installed in the machine can, to be able to switch from pipe jacking to segment lining in case the machine gets stuck. The overall aim is to provide clients and the tunnel construction industry with safe and economical solu- tions for successful project execution. This presentation will present international milestone projects and will also discuss the latest developments in automation, related opportunities and limitations, and the future of digitization and artificial intelligence in pipe jacking.

Jun 23, 2024

By Aurel Goodwin

I chose the title "Let's Clear the Air" for this afternoon's presentation because it has two meanings, the literal and the figurative. Most of you know what MSHA is. Most of you know what MSHA does. And, for the most part, most of you know why. What I hope to accomplish today is to "clear the air" around our health standards, to clarify for you how MSHA views its congressional mandate under Title I Section 101(a)(6), (7), and (9) of the Mine Safety and Health Act. Asbestos, silica, radiation, noise, welding fumes, carbon monoxide, lead, hydrogen sulfide, nitrogen dioxide - the list of physical and chemical hazards encountered in the metal and nonmetal mining industry is as diversified as the industry itself, possibly even more so. In addition, miners are often exposed to several of these health hazards simultaneously.

Jan 1, 1980

By Carrie Smith

This fall, the Society for Mining, Metallurgy & Exploration (SME) will begin a new chapter by welcoming its new executive director and chief executive officer (CEO). Melissa Russell, a successful nonprofit executive with more than 30 years of experience in global association management, officially stepped into the role on Sept. 29, 2025. She succeeds longtime CEO Dave Kanagy, CAE, who is retiring in March 2026 after more than two decades of transformative leadership. “I am honored to begin this new chapter with SME and inspired by the vital role this community plays in shaping our world,” said Russell. “I look forward to listening, learning and working alongside this remarkable group of professionals to advance innovation, champion sustainability and create a brilliant future together.” Russell brings a deep portfolio of leadership experience in technical and industrial associations to SME. Most recently, she served as executive director of the Institute of Electrical and Electronics Engineers (IEEE) Computer Society, the largest of the IEEE’s 39 societies, with more than 50,000 members across 150 countries. During her tenure, she strengthened global engagement, advanced financial sustainability and launched strategic humanitarian initiatives.

Oct 1, 2025

By Ron Robinson, Trevor Harrison

The planning, installation and commissioning of the first scheme of controlled recirculation of air flow in a section of coal mine in Great Britain is described, together with the proposals for a second installation. The work updates a previous paper (Robinson and Harrison, l986) on the subject. The special problems of ventilating the increasingly distant faces of the undersea mines in the North East Area of the British Coal Corporation are discussed and the alternative solutions stated. The advantages of using a system of controlled recirculation of air are proposed together with the safety features considered necessary. Design and installation details of the recirculation fans and a new booster fan are described.

Jan 1, 1987

By A. M. Marabini

Flotation of rutile with N-benzoyl-N-phenyl-hydroxylamine (N-BPHA) has been investigated. Initially, floatability tests were performed in a Hallimond tube. The results indicated that rutile was floatable in the pH range from 2 to 4 at N-BPHA concentration between 2x10-3 M and 2x10-2 M. Selectivity against hematite was recognized when operating at pH values below 2. Following the hypothesis of the formation of a surface chelate between N-BPHA and titanium ion, this compound was precipitated from a solution of Ti(SO4) to which N-BPHA was added. I.R. spectrometry oft the rutile before and after treatment with N-BPHA solution confirmed the presence on the rutile surface of the same compound. The absorption isotherm and kinetics were determined by analyzing N-BPHA in solution with an U.V. technique. A hypothesis for the mechanism of adsorption of N-BPHA on rutile is suggested.

Jan 1, 1982

By Whitmell J. Smithwick

Lime is one of the most extensively used chemicals in industry. Other than sulfuric acid, it is used in greater quantities than any other man-made industrial chemical. In 1974 there were 20,368,000 tons of lime used in the United States, which amounts to approximately 190 pounds for each man, woman and child in our nation. Lime also is perhaps the most diversely used of any industrial chemical. It is used in such areas as pharmaceutical, chemical, steel making, glass making, production of copper and aluminum, sugar refining, agriculture, construction, ecological endeavors, potable water treatment and sanitation. Figure I lists the major uses of lime for 1974, which is the latest year for which this data is available. The impact of the use of lime for ecological reasons did not show up to any appreciable extent in 1974, but we expect this to be a significant factor within the next few years. Fortunately, in the United States and also in most of the world, there are many deposits of high quality limestone available for the production of hood quality lime. For this discussion, we will assure that a limestone of a suitable quality and size consist will be available in a storage bin or stockpile near the kiln. Quality requirements for the lime product will be covered. We also will give a brief description of the three most popular types of lime calcining systems, how they function, and expected lime product quality from each of these. Commercial fuels and major accessory equipment will be discussed briefly.

Jan 1, 1976

By M. A. Rodrigues da Silva Enríquez

One of the rare consensual points among different resource-based economic analytical approaches refers to the strategic role of rent from mineral extraction, as a decisive tool to ensure that the temporary wealth generated in the present can turn into permanent income in the future. For this reason, evaluation, distribution and use of mining rent plays a central role in the sustainable development of mining cities. Brazilian legislation provides for this at the municipal level by means of participation in the financial results of mineral extraction accomplished in these municipalities, with the Financial Compensation for Mineral Exploration (CFEM). CFEM is a type of ad valorem royalty, which charges taxes of up to 3% of the net revenue of mineral production. However, legislation does not establish how these resources should be used. Therefore, there is wide variation in the use of CFEM income among Brazilian mining cities. A study from a sample of the 15 largest mining cities in eight Brazilian states made possible identification of two main patterns with regards to the use of CFEM which were labeled "sustained use" and " the pitfall of the single treasury." In that regard, this article discusses the pressuring factors that contribute to these patterns, as well as the institutional arrangements which may be more favorable to inducing more sustained use of CFEM.

Jan 1, 2011

By Karoly (Charles) Kocsis, Jeff Johnson, Felipe Calizaya, Tulio Dias, Natanna Nunes

Two pressure balancing chambers were constructed at a Colorado coal mine to reduce the risk of spontaneous combustion. Each chamber was established by installing a Kennedy stopping at about 10 ft (3 m) in front of an isolation seal, and equipped with two safety doors, a nitrogen injection system, and a set of environmental monitors. Several pressure balancing tests for different ventilation conditions were conducted in these chambers. During each test, pressurized nitrogen was injected into the chamber and the pressure differentials across the stoppings and seals monitored. This study presents a summary of the results achieved, lessons learned, and the basic requirements to operate a pressure chamber effectively.

Feb 1, 2024

By E. L. Montgomery

Salar basins in the Andean Highlands of Northern Chile contain ground-water resources which could be used to satisfy requirements for the mineral industry in the region. Salars occur in arid zones; average precipitation is about 200 millimeters per year at altitudes of about 4,000 meters, and average annual evaporation is two meters or more. The salar basins are hydrogeologic sinks where water flows from recharge areas at the margins of the basins to discharge areas at the salt encrusted salar at the lowest point of the basin floor. Groundwater circulation occurs principally in the alluvial and fractured bedrock aquifers. Results of pumping tests for exploration and production water wells indicate a range in maximum sustained pumping yield of 62 to 126 liters per second, and where abundantly fractured, ignimbrite comprises the most prolific aquifer. Chemical quality of groundwater is good. Long-term pumping from properly located production wells in the salar basins would result in lowering of groundwater levels and salvage of water in areas where groundwater is lost via evaporation.

Jan 1, 1986

By Staff

GENERAL DESCRIPTION The Lucky Friday mine is located in Mullan, Sho-¬shone County, Idaho. The mining method is horizontal slice cut-and-fill (with timbering for support or un¬timbered) using hydraulic sand. Cemented sand fill at a 1:17 ratio is used in sill pours and at a 1:7 ratio for the final 152 mm (6 in.) capping in successive stope floor pours. Annual production with 100% cut-and-fill mining is 167 829 t (185,000 st). The average depth of mining is 1296 m (4250 ft) and the average travel time to the stope is 45 min. GENERAL ORE BODY REQUIREMENTS AND LIMITATIONS Size The ore body is 396 to 488 m (1300 to 1600 ft) long on strike, 1421 m (4660 ft) on dip, with an average width of 2.3 m (7.5 ft). Dip varies from vertical to1.2 rad (70°) Ground Conditions, Ore Value, and Production Requirements The ore body contains quite strong argentiferous galena and quartz. The hanging wall and footwall are strongly sheared and fractured. Ore value is $211/t ($192/st).

Jan 1, 1982

By David R. Klug, Chris Gause, Troy L. Page

The Inter-Island Tunnel is one of two undersea tunnels which are part of the Boston Harbor Clean-Up Program. The tunnel is 7.7 km (25,160 ft) long, bored to a 4.3 m (14 ft) diameter in the Cambridge Argillite Formation and was finished to a 3.5 m (11.5 ft) diameter final concrete lining. The owner is the Massachusetts Water Resources Authority (MWRA) who is a regional authority responsible for overall design and construction. The tunnel's primary purpose is the transport of untreated effluent from Nut Island facility in Quincy, MA to the new treatment plant at Deer Island. Two sludge lines are installed for the transport of sludge from Deer Island to Nut Island. During construction the contractor encountered fault zones, fractured strata, and soft ground tunnel sections which liberated more ground water than was originally anticipated by the project designer. Ground water was controlled during mining and the placing of the final lining. The final lining of cast-in-place concrete had to be backfill grouted to cut off water inflows and provide contact for equal tunnel loading which is critical in long-term design. This paper deals with an engineered backfill grouting system which was the first of its type to be used in North America. It discusses the geological conditions encountered, the design criteria used in the evaluation process, and an indepth review of the various system components. It demonstrates how contractors can use knowledgeable and professional industry suppliers to solve difficult construction problems.

Jan 1, 1999

By Rui Xiang Yang, Cong Li, Jia Zeng, Rong Liang Zhang, Wei Zhang, Chao Fan Tang

This research took the roasted products obtained by leaching copper (Cu) refining slag using waste acids and roasting leaching residues with calcium oxide (CaO) as raw materials and used oxidative leaching to extract Cu from roasted products using waste acids. Influences of the leaching temperature, liquid–solid ratio, and sulfuric acid ( H2SO4) concentration in waste acids on the leaching rate of Cu in the oxidative leaching process of roasted products using waste acids were investigated. The unreacted-core shrinking model of heterogeneous reactions was adopted to reveal the leaching kinetics of Cu in the oxidative leaching process of roasted products using waste acids. Results show that the leaching rate of Cu reaches 91.68% when the leaching temperature, liquid–solid ratio, H2SO4 concentration in waste acids, and injected airflow are 80 ℃, 8:1, 1.5 mol/L, and 200 mL/min, respectively. If the leaching temperature is below 80 ℃, the leaching process of Cu is controlled by the solid-film diffusion, and the apparent activation energy Ea is 11.0835 kJ/mol; at a leaching temperature above 80 ℃, the leaching process of Cu is governed by the interfacial chemical reaction, with an apparent activation energy Ea of 42.3183 kJ/mol. The liquid–solid ratio can positively influence the reaction rate constant. The apparent order of the leaching reaction of Cu is 0.632.

Jan 11, 2023

By D. W. Park

Longwall mining is considered the most efficient underground coal mining technique in terms of coal extraction ratio, production rate, and safety standards. Due to the increasing demand for higher coal production, wider panel and faster face movement have become the recent trends. Thus, longwall mining can create unexpected threats such as roof falls, excessive face convergence, shield damage and numerous maintenance problems causing sudden interruption of coal production and serious safety hazards. A recent study at the University of Alabama is dedicated to develop LoSCoMS (Longwall Strata Control and Maintenance System) which integrates real-time shield monitoring, data presentation, analysis, forecasting, and warning modules. The main objectives of this system is to provide the stability and maintenance information, at every minute, such as high load, low setting pressure, leg leakage, etc., analysis of various mining and geological parameters to determine past and present roof characteristics and forecasting of loading patterns for the following mining cycles, next periodic weighting, etc. Using this unique system, mine operating personnel are well aware of past, present and future roof loading patterns at the longwall face, and thus, proper safety measures can be taken ahead of time.

Jan 1, 1997

By R. N. Torbin

The degree to which automation, remote control and robotics have been used in the mining industry is far less compared to general industry. Reasons include the adverse working environment, the difficult work operations and the generally lower incentive for capital investments in new mining equipment. The author and his employer has been involved in the development of advanced mining and underground construction equipment. This equipment is designed to he remotely operated, to improve both productivity and worker safety. Many of these machines employ advanced electronics and robotic features. The types of machines that will be discussed include remote shaft lining and placement, remote excavation and mining operations, and automated conveyor systems.

Jan 1, 1991