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By Ali Ekrem Aritan

Exposure to hand-arm vibration (HAV) among the labor force in the mining industry can result in permanent vibration diseases such as behavioral disorders, visual impairment, osteoporosis, pain (mostly in the hands, wrists, and shoulders), circulatory system disorders, and malnutrition. In this study, the vibration exposure of excavator operators working regularly in 25 different natural stone quarries was measured. In addition, the relationship between vibration exposure and rock properties was investigated. Gloved and ungloved vibration measurements were performed and revealed that antivibration gloves reduce excavator operators’ vibration exposure by 7.10–25.95%. Samples from each quarry were characterized with rock mechanics tests. The correlations between the hand-arm vibration measurements and the natural stone physical–mechanical properties (uniaxial compressive strength, Shore hardness, Knoop hardness, apparent density and total porosity) were determined to be over 70%. One finding of the study was that the health risk in excavators cannot be reduced sufficiently by the sole use of antivibration gloves. Furthermore, the excavation of any rock with a Knoop hardness above 121 is associated with an 81% risk of HAV. To increase awareness of the danger of vibration exposure for natural stone miners, training programs should be provided, and technical and operational changes should be implemented.

[The development of economically effective and safe methods of mining thick coal seams enables to involve considerable coal reserves into the energy resources in different countries all over the world.]

Jan 1, 1975

By Ravi Sahu

"In the global mining industry, there are those who seem resigned to the fact that the mining industry has always operated according to certain time-tested principles that don’t involve jumping on every new technological trend. Others expect that mines will soon have autonomous electric vehicles running around the clock. The truth lies somewhere in the middle. In business, as in life, that is usually the best path to follow.The instant access to people and information provided by 21st-century technology continues to push businesses in all industries toward greater efficiency and unheard-of levels of modernization. And in the world of mining, the embrace of advanced technology is all about managing risk.However, even in this age of digital information overload, some mine sites still require employees to physically download data from individual trucks to monitor payload data and inspect road conditions using a clipboard. What’s more baffling is that other mine sites still have no way of tracking tons moved at all.This isn’t due to a lack of innovation in the industry. Quite to the contrary, there is an abundance of new technology available that provides real-time monitoring of vehicle movements and tracks road conditions without the intervention of people. So why are owners reluctant to embrace advances in mining tech?Gauging the value of changeSurvey data has traditionally been captured by ground laser scans and LIDAR systems. A mine site surveyor would drive around the pit with a truck-mounted scanner to generate a point cloud. This process would be completed every few days and would take an entire day.The many cons of this method far outweigh the pros. First, it provides no visual data. If an operation has moved beyond the roller wheel and tape measure, visual pit models and LIDAR scans are typically completed once every six to 12 months by an aerial flyover, but such sporadic information gathering isn’t likely to result in the most actionable data. Moreover, given the high cost (in terms of both money and time), the numerous safety and liability issues, and the lack of flexibility in scheduling, manual processes are more trouble than they are worth.Overall, while miners are excellent operators who value innovation, their employers often try to outsource it or acquire innovators instead of investing in existing technology that can improve current operations. It is a never-ending dilemma:"

Jan 5, 2018

By Joseph Corvetti

This paper is of conceptual nature. The authors present their idea of creating an integrated and intelligent excavation design system. Research work has just been started and the results will be addressed during presentation of this paper. The authors are currently engaged in a pilot study and expect to build a feasibility prototype expert system (establishing the numerical-cognitive coupling in excavation design) by the end of this year.

Jan 1, 1996

By Luigi P. Gonano, John C. Sharp

The Drakensberg Pumped Storage Scheme in South Africa with an operating head of 500m is located in sedimentary rocks containing relatively weak argillaceous strata. The paper describes design and construction aspects of the high pressure concrete-lined tunnels, and the associated investigation techniques and construction controls.

Jan 1, 1983

By M. S. Vernon, J. J. Kellar, W. M. Cross, R. M. Winter, F. J. Johnson, A. G. Pommer

Three substrates (MgO crystal, CaF2 crystal and Mg plate) were used to construct thin layers of Mg(OH)2. Various routes were used to modify these substrates, including surface hydration and sol-gel coating. In each case, it was found (by using Fourier transform infrared spectroscopy) that thin layers of Mg(OH)2 could be produced. In the case of hydrated layers, the surface morphology of the Mg(OH)2 resembles the bulk platelet shape of precipitated Mg(OH)2.

Jan 1, 2000

By A. C. T. Bigg, A. F. Colombo, A. R. MacPherson

The step-by-step study of the Stronsay ores follows the testwork through the initial determination of Bond Rod and Ball mill work indices, the MacPherson Autogenous work indices and the production of a preliminary flowsheet. These results are then used to design a pilot plant program to test the effectiveness of fully autogenous primary and secondary grinding and to determine the feasibility of controlling feed rate by the use of variable speed mill drive and/or varying the mill load. A final flowsheet is recommended with mill sizes and power requirements.

Jan 1, 1992

By J. Shibata

Separation of rare earth, especially Nd and Sm, was investigated by batch and column methods with a solvent impregnated resin. The solvent impregnated resin was prepared by impregnation of organo- phosphorous extractant whose trade name was PC-88A into a macro porous resin. The adsorption behavior of rare earth with a solvent impregnated resin in a batch method is the same as that with solvent extraction. In a column method to separate Nd and Sm, the effective separation in both adsorption and elution processes can be attained by setting suitable conditions, such as bed height, flow rate and concentration of eluent. Neodymium which is a lighter rare earth is separated from Sm an adsorption step, while Sm in which is a heavier rare earth is recovered in an elution step. From the integration of breakthrough and elution curves, yield of Nd and Sm is calculated in the condition of 100% purity. It was found from the results of life test of the resin that the solvent impregnated resin can be repeatedly utilized at least 20 times.

Jan 1, 1995

By L. J. Prosser, A. T. Iannacchione

From 1991 through 1995, 44 miners out of a total workforce of less than 2,000 were fatally injured in the stone industry. Of these, 12 occurred at underground mining operations with nine deaths resulting from roof or rib falls. A safer environment can be achieved by evaluating the nature of the hazardous ground and by developing more efficient and effective ground-control strategies. Roof and rib conditions were observed and assessed in 33 underground stone mines in Illinois, Indiana, Kentucky, Maryland, Missouri, Pennsylvania and West Virginia (Fig. 1). Hazard assessment indicated that the ground failures that occurred under moderate to substantial overburden, i.e., >30 m (100 ft), were caused by stress concentrations and geologic structures. Ground failures near the surface are caused by solution (water) processes. Selection of the mining horizon and mine-layout decisions

Jan 1, 1999

By Robert A. Jankowski, Natesa I. Jayaraman, Jay F. Colinet

The U.S. Bureau of Mines evaluated the dust control effectiveness of two-phase flow systems in a full-scale model mine using a mockup of a Joy 14CM continuous mining machine. In a two-phase flow system, air and water flow simultaneously through the nozzle. Air pressure varies from 10 to 60 psi, and water at 30 to 50 psi. Coal dust was introduced at the face, and dust concentrations were monitored at the operator locations and in the return. When compared with a conventional spray system, a symmetrical two-phase flow system reduced dust levels during the box cut by 43 pct at the operator location, and 30 pct in the face return. Dust levels, however, increased at the off-operator position during the slab cut. A directional two-phase flow system reduced dust levels at both operator locations by more than 90 pct in the box cut mode. While the use of two-phase flow systems will reduce respirable dust levels and water usage, it requires an air supply to the miner. Moreover, the ability of the two-phase flow system to redirect the dust cloud makes nozzle orientation a critical factor.

Jan 1, 1991

By David J. Kruse

Accurate field measurements are essential when validating a conveyor design. They are fundamental in determining a conveyor's behavior, its long-term maintenance requirements, and the life expectancy/ condition of the installed equipment. Field measurements are also invaluable in forensic engineering, particularly when vital equipment has failed This paper will discuss a wide variety of data acquisition equipment, field measurement techniques and accuracies achieved State-of-the-art, custom designed monitoring equipment, as well as, ''08-the-shely instruments and sensors, will be discussed.

Jan 1, 2004

By Aleksandar N. Nikoloski, Rorie Gilligan

Brannerite, UTi2O6, is the most common of the refractory uranium minerals and requires leaching under intense conditions to effectively extract the uranium contained within. Brannerite is often found together with apatite in metasomatic uranium deposits. Apatite and other phosphate gangue minerals can inhibit uranium leaching by generating phosphate ions which interfere with the reactions between acidic ferric sulphate and uranium minerals. As part of a detailed fundamental study on the leaching reaction mechanisms for brannerite, tests under a range of selected leach conditions were carried out with the addition of 10 g/L fluorapatite with the goal of identifying conditions where the negative effects of phosphate are reduced. Leaching was carried out for 5 hours with 0.05 mol/L Fe3+ as Fe2(SO4)3 with 0.25–1.00 mol/L H2SO4 and at temperatures between 25 and 96 °C. A single test was performed with 0.05 mol/L Fe3+ as FeCl3 and 1.00 mol/L HCl. In the sulphate system, the effect of phosphate was weakest at the highest acid concentration (1.00 mol/L H2SO4). In the chloride system, phosphate did not suppress uranium extraction, suggesting that HCl leaching could be a viable alternative for the leaching of high-phosphate refractory uranium ores.

Mar 17, 2021

By Lana Alagha, Keitumetse Cathrine Monyake

The abstract discusses the synthesis and investigation of polyacrylamide functionalized chitosan polymers (CS-PAMs) as selective depressants for pyrite in the flotation of galena and chalcopyrite from complex sulfide ore. The study employed response surface methodology (RSM) to model and optimize the flotation process, varying parameters like the degree of deacetylation of chitosan, weight ratio of chitosan to acrylamide, and CS-PAM dosage. The developed RSM models effectively predicted iron and lead grades and recoveries, while optimization showed optimal pyrite separation from galena and chalcopyrite using CS-PAM synthesized from chitosan with a high degree of deacetylation and a specific chitosan:acrylamide weight ratio.

Apr 9, 2022

By Sean Hunter

Artificial Intelligence has a long history but is currently coming strongly into focus with new advancements. This leads to questions many people are asking: what exactly is AI, how can it be used effectively in mining operations, and what foundation is required to make AI implementations successful? In mining, many AI applications exist, from drill pattern optimization to predictive maintenance. However, many implementations struggle due to data integration challenges. Mining operations generate large amounts of data from many sources, such as fleet management systems, drill sensors, process control systems, and laboratory results. Unfortunately, this data often exists in silos where it’s difficult to get it out, making AI applications unable to leverage it. Worse still, tools that use AI don’t always provide their data back to the system, creating even further data silos. All these problems make it hard to take advantage of the data at the mine, slowing down and reducing the effectiveness of AI. This paper presents a comprehensive approach to organizing mining data using an AI-ready knowledge graph system. We will first explore the evolution of AI in mining, from early expert systems to modern machine learning applications. Then, we will detail how a knowledge graph can integrate business context, operational data, and AI models into a cohesive system that enables more effective AI implementations across mining operations. The proposed method has been developed considering both the unique data challenges faced by the mining industry, while also considering best practices learned from the AI field at large. By following this approach, it’s possible to better utilize existing data, getting higher quality and more complete results faster, and in a way that’s reusable and composable.

Feb 1, 2025

By Ewan Wingate, Ranjit Prasad, Yanjun Liu

The phosphorus journey begins with the extraction of primary phosphorus in the form of phosphate in apatite through openpit mining and, in some rare cases, underground mining methods. The ores are processed in beneficiation plants to remove impurities before the phosphate rock concentrate is either sold on the open market or converted into phosphoric acid in downstream chemical production facilities by the wet acid process or thermal phosphorus routes. These can in turn be converted into fertilizers, as well as used in the food and electronic industries. The advent of the EV battery has given rise to a new use for purified phosphoric acid in the production of lithium ferro phosphorus (LFP) cathode material for EV battery cathode assemblies. The production of LFP relies on raw materials such as lithium carbonate, lithium hydroxides, iron salts and purified phosphoric acid.

Feb 1, 2024

By S. Park

In a flotation froth (and foam), air bubbles become larger due to coalescence, causing less hydrophobic particles to drop off. A bubble-coarsening model has been developed by calculating the changes in Plateau border area as a function of the initial bubble size at the base of a foam, liquid fraction, and foam height and then relating the predicted Plateau border area to the critical rupture thickness of lamellae film. The model predicts that bubble coarsens with increasing froth height, decreasing frother dosage, and decreasing aeration rate. The model predictions are in good agreement with actual bubble size measurements.

Feb 23, 2014

By Manoj Kumar, Anil Kumar Singh, Prabal Patra, Ashish Agrawal, Souvik Ghosh, Subhashis Kundu, Kamma Ramakrishna Rao, Manish Kumar Gupta, Anindya Sarkar

The slag measurement systems in the cast house are very important. In the conventional method, the slag is granulated in a slag granulation system, and the slag flow rate is measured by the associated belt scale. However, in places where a slag granulation system is not available, the alternate approach is to deduce a theoretical calculation and develop the measurement because the commissioning of such slag granulation requires huge capital and has inherent geographical limitation. However, the theoretical approach suffers from several drifts and is far from the reality. In the present paper, we have innovatively engineered a sensor by designing the stellite-coated thermocouple that can measure the temperature of the slurry and placed it in such a way that the abrasive slag granules do not obstruct it, but we could measure the temperature of hot water, and further based on the thermodynamic approach, the slag flow rate is determined that can be compared with the theoretical approach. This approach of slag rate measurement is cost-effective and long-lasting.

Oct 2, 2023

By W. S. Sanner

Experiments were conducted to determine the quantity and purity of ultraclean anthracite that could be prepared in the laboratory, using conventional separating techniques. A low-, a medium-, and a high-volatile anthracite were studied. Specific gravity separation followed by grinding, screening, and refloating at lighter specific gravities yielded small quantities of material purified to 1.0 percent ash, as follows: From low-volatile anthracite, 0.7 percent; from medium-volatile coal, 1.0 percent; and from high-volatile coal, 2.3 percent. The reduction in ash had no appreciable effect on the volatile matter or sulfur content of the coal. The limited quantities of material containing 1.0 percent or less ash obtainable indicate that if ultraclean coal is desired, a practical approach should include the processing units as an integral part of a conventional dense-media washing plant.

Jan 1, 1968

By Claudia Castillo, Katja Freitag, Jan Cilliers, Diana Drinkwater, Robert Seitz

The talent gap in mining is not a new challenge. Mining companies continue to seek innovative ways to attract, develop and retain talent, and younger workers are looking for opportunities to develop their professional careers. Training provides a key value proposition for both employees and employers as it helps build a talent pipeline while offering opportunities for learning and growth and value creation. In 2020, Metcelerate launched its 20-month program for early career mineral processing engineers. The program helps develop critical technical skills in the workplace and is a tool to identify motivated engineers and change culture within teams. Learners cap their skills development by executing a technical investigation. This generates immediate value—a win-win outcome for learner and company.

Feb 1, 2025

By Jerry C. Tien

The rare earth elements (REEs) are a group of 17 chemical (metallic) elements which appear in the periodic table. The group consists of 15 lanthanide elements along with yttrium and scandium (Table 1). They share many similar properties, which is why they occur together in geological deposits. Although commonly referred to as rare, they are really quite common; the reason they are perceived as rare is because it is not common to find them in commercially viable concentrations. These metals are critical to advanced technology, ranging from smart phones to global positions system (GPS) receivers, medical devices and jet engines. They are critical in green, high-tech and defense industries (Fig.1 and 2). Although there have been increasing efforts to find alternative supplies, these efforts have been complicated by the pollution that rare earth mining and processing creates. To extract rare earths minerals from mined ore is a complicated and costly process. The ore is first mined through normal mining process, the bastnaesite, which generally contains a number of minerals of little value, is first removed through a floatation process. The bastnaesite containing the REEs is further separated into their respective pure forms in a separation plant using acid and various solvent extraction separation steps. Each element has its own unique extraction steps and chemical processes. At times, these elements, in the form of oxides, will require reprocessing to achieve ideal purity. The last steps would be to further process into metals first, then alloys for various applications. The entire process takes approximately 10 days. The mining and processing of REEs, if not carefully controlled, can create environmental hazards. This is one of the reasons the Mountain Pass Mine in California was closed down in the 1980s.

Dec 1, 2013