Search Documents

By M. A. Georgiana

The Emerald Mine No. 1, located in southwestern Pennsylvania is presently owned and operated by Cyprus Minerals of Englewood, Colorado. High volatile bituminous coal is produced from the Pittsburgh No. 8 seam by both longwall and continuous mining methods. The coal is then mechanically cleaned on site utilizing a combination of heavy media separation and froth flotation methods prior to shipment to both the metallurgical and steam coal markets. The Emerald Mine is presently producing 2.8 million raw tons per year, while liberating approximately 6.5 million ft per day of methane. In light of the methane liberation rate, ventilation requirements have been significant and have always received utmost priority and consideration. Figure 1 shows the locations of the current and proposed shafts. Emerald utilizes two Joy (Model M120-58-880) axial vane fans on shafts No. 1, No. 2R, No. 3R. (one operational, one stand-by) The use of computer simulation of various ventilation networks was initially employed during the design stages (1975-1977) and has been utilized through the present. Obviously, the initial planning, under the ownership of Lykes Resources, was strictly theoretical. All the quantities were proposed and the resistances were based on prior simulations of other mines and mathematical formulas. However, once the mine was moderately developed, actual values were recorded and utilized. This procedure consists of: a) layout pressure and quantity points b) measure all air quantities where an air course splits

Jan 1, 1986

"A carefully planned laboratory test program is the foundation for the successful development of a sulfide flotation process. In this paper, the development of a copper-molybdenum flotation process is described. However, the concepts discussed can be applied to most sulfide flotation systems and to many industrial minerals projects as well. Each step is examined, beginning with sample procurement and covering sample preparation, flotation test preparation grinding, scoping flotation tests for reagent scheme selection, rougher flotation parameter evaluation and cleaner circuit evaluation, through to locked-cycle testing and pilot plant design and operation. Ore variability and modeling to determine the response of various ore types to the optimum conditions established is also examined.IntroductionA carefully planned laboratory test program is essential for the successful development of any sulfide flotation process. These programs usually begin with a series of batch tests on several ore type composites to evaluate appropriate reagent schemes and delineate optimum rougher flotation conditions, such as primary grind size, flotation pulp density, flotation pulp pH and retention time. Cleaner parameters such as regrind size requirements, cleaner pH, pulp density and number of stages are then defined. Semicontinuous locked-cycle tests are performed using the parameters established in the batch tests to determine the effect of middling streams recirculation on flotation performance. The data generated and the experience gained in the locked-cycle tests may be used to design and operate a continuous pilot plant if relatively large amounts of concentrate are required for further process development, such as optimization of byproduct molybdenum production from bulk copper-molybdenum concentrate.A comprehensive ore variability program is undertaken to determine the response of various ore types to the optimum conditions established. These ore variability programs often test hundreds of samples in standardized batch rougher and cleaner tests to ensure that the orebody is well understood.This article describes the development of a copper-molybdenum flotation process, but the concepts discussed can be applied to most sulfide flotation systems and many industrial minerals projects. The block flow diagram in Fig. 1 provides an overview of the development process."

Jan 1, 2016

By Milka Madahana, John Ekoru

For efficient management of operations, mining companies are required to be able to predict potential scenarios for main market factors. Competitive advantage and value creation are established through managing the value chain well. The mining value chain is usually faced with challenges from various shifts in commodity markets as well as ongoing uncertainties. Therefore, there is a need for accurate analysis of data from the markets, for the prediction of commodities, for instance, Precious Group Metals (PGM). The main objective of this research work is to apply machine learning methodologies with the aim to identify patterns and trends in the Precious Group Metals, and thereafter analyze and predict the future trends of these markets. Numerous machine learning models are applied to a dataset consisting of 15 years of daily price for eight precious metals namely Platinum, Palladium, Rhodium, Ruthenium, Osmium, Indium, Silver, and Gold. The results reveal the patterns and trends within the data sets and that different machine learning methods could be suited for the prediction of market prices for each of the PGMs. The application of an amalgamation of various machine learning methods may result in more accurate predictions of the PGM markets. Accurate prediction of market prices for PGMs will possibly result in unlocking untapped sources of value in the mining industry.

Jun 25, 2023

By M. Xing, S. Usman, K. Awuah-Offei

"While mines generally focus on achieving operational efficiency, creating shared value for all stakeholders is also a management goal. This includes taking a holistic view of their supply chains and increasing local participation. This paper examines the role of supply chain management in mine management; in particular the effect of a strong local supply chain on regional economic impacts. Using input-output analysis, the impact of a local supply chain on a mining sector’s regional economic impact is examined by increasing local sourcing (increasing local purchase percentage -- LPP) for 10 key commodities. An approach, based on multipliers and excess local capacity is used to identify key commodities. The impacts examined are sales, employment, labor income, and value added. The work is illustrated with stone mining and quarrying in Missouri. Ten percent increases in LPP of the key commodities, in this example, result in $4.1 million additional impact on the Missouri economy. This work can provide insight on how to better create shared value for all stakeholders. INTRODUCTION Little research has been published on improving mine supply chain management (SCM) to enhance regional economic impacts. Although some extensive academic research has explored the importance of an industries’ supply chain, not much is known about how a locally-based supply chain increases shared value in the resource sector. Across industries, traditional SCM is getting more and more complex. This is true of the mining sector as well. However, this increased sophistication is not directed towards increasing shared value for all stakeholders, particularly, the local communities. Further research is required to develop new SCM strategies that enhance local participation. One major point of difference between this work and traditional supply chain management is the inclusion of stakeholders’ shared value as a goal in SCM. Creating shared value has become a business goal in recent years (Porter and Kramer, 2011). The authors use input-output analysis (Leeuw, 2012) to evaluate the regional economic impacts of supply chain decisions, which is not part of traditional SCM. Although input-output analysis has been applied to SCM for decades, most of the research uses input-output analysis as a tool to advance an industries’ own operational efficiency (Accenture, 2014)."

Jan 1, 2015

By Virginia T. McLemore, Devlon R. Shaver

Clinkers are the result of a seam of coal catching fire and burning the surrounding rocks. The fires caused the surrounding rocks to be baked at high temperatures, removing organic material and partially forming glass. These rocks become hard, orange, and brick like, forming clinker. The purpose of the study is to determine their potential to contain economic levels of critical minerals, including Rare Earth Elements. Some clinkers contain over 200 ppm total REE.

Feb 1, 2024

By E. A. Devuyst

Metallurgical processes involving the use of cyanide such as gold cyanidation, metal plating and flotation, generate effluents containing cyanide and cyanide in complex combinations with heavy metals in quantities exceeding those regarded as being safe for discharge into streams. A new process for destruction of free and complexed cyanide and related-species in wastewaters has been developed at the Inco research laboratories using sulfur dioxide, air and lime. High reaction rates are obtained in the presence of a small amount of copper which acts as a catalyst. Cyanide species can be reduced to as low as 0.1 mg/L in a very short treatment time. Examples of treatment of gold mill effluents and barren slurries, plating rinse waters and flotation liquors or tailing slurries are given.

Jan 1, 1982

By Steve Axen

In situ mining is now considered an alternative mining method for some ore bodies. The in situ operation consists of a well field designed from reservoir properties and geological information; the wells for such a field are then drilled, cased, and cemented, using good designs and practices to eliminate future problems. Injection and production (recovery) systems are required to be corrosion resistant. Hand in hand with the mining operation is the metal extraction plant, the entire operation offering an environmentally acceptable method for metal recovery. Great opportunity exists in this field for mineral engineers; presently, they must borrow knowledge from other fields, since the schools have not yet addressed this specialty.

Jan 1, 1979

By Jaeheon Lee, Junmo Ahn, Jae-Yeon Kim, Yoo-Jin Kim, Jiajia Wu, Eun-Woo Kim, Jai-Won Byeon, Jun-Jae Lee

The surge in demand for battery materials, coupled with environmental challenges linked to battery disposal, underscores the need to recycle spent lithium-ion batteries (LIBs). Green recycling approaches, in particular, have garnered attention for battery recycling. In this study, a hydrometallurgical method using a synergetic organic lixiviant combining methanesulfonic acid (MSA) and citric acid (CA) as an alternative to inorganic mineral acids was introduced as a green approach to recycle cathode materials of LIBs. The conditions for leaching and recovery processes were optimized. Cathode materials were regenerated using the recovered materials. Moreover, the leaching performance and economic feasibility of this leaching system were compared with those of various other organic acids.

Feb 1, 2024

By Atta Ur Rehman, Kwame Awuah-Offei

This paper examines the effect of bucket geometry (cutting-blade profile, floor profile and blade thickness), speed, motor power output and muckpile particle sizes on bucket penetration and draft for rubber tire loaders. The work uses a 1:16 scale model of a load-haul-dump (LHD) in full-factorial experiments to examine the effect of the variables on penetration and maximum draft. The results show that speed and motor output are positively correlated with penetration and draft, and muckpile particle size is positively correlated with penetration and negatively correlated with draft (p < 0.0014).

By George M. Hamilton

The gas producer actually dates back far beyond the period from which we first find recorded data. A partial production of producer gas can take place in any type of solid fuel grate equipment, such as a boiler, or even a fireplace if a sufficiently deep fuel bed is provided. Those of us who have watched a coal fire burning in the hearth, have no doubt noticed at times, the gases liberated by the heat burning on or near the surface of the fuel bed. So far as we know, the first gas producer was built by Bischof in Germany in 1839, followed by Ebelman in France in 1840, and Ekman of Sweden in 1845. The first large industrial development in the use of gas producers was When the two Siemens brothers of Germany patented their first combined gas producer and regenerative furnace in 1861, thus opening up the field for the use of raw, crude producer gas in heavy furnace work. In the years 1879-1881 J, E, Dowson, of England developed a producer gas cooling and cleaning plant, which extended the scope of application of producer gas to make possible its use in small furnaces and gas engines.

Jan 1, 1961

By Norm Greenwald

The Environmental Protection Agency ("EPA") has been attempting to develop a federal regulatory program for mine waste under Subtitle D of the Resource Conservation and Recovery Act since 1986. Recent regulatory and legislative events are now bringing this goal closer to reality. This paper discusses the mining industry&apos;s perspective on a number of the issues currently being addressed at EPA&apos;s Policy Dialogue Committee and in Congressionally-sponsored negotiating sessions.

Jan 1, 1992

By Michelle Pienaar, Musa S. D. Manzi, Thabang Kgarume, Glen T. Nwaila, Raymond J. Durrheim, Abrie Oberholster, Hennie Grobler

The South African Mining, Extraction, Research, Development and Innovation (SAMERDI) strategy was launched in 2019 with the goal of modernizing the mining industry. It comprises three major research initiatives: improvement in the efficiency of extraction and health and safety in current mining operations, development of fully mechanized systems to mine narrow tabular ore bodies in hard rock, and development of extraction systems to break rock without using explosives. The crosscutting Advanced Orebody Knowledge (AOK) program seeks to develop and implement drilling and geophysical technologies that can characterize the rock mass ahead of mining and identify potentially hazardous geological features. This knowledge will be integrated with information derived from seismic monitoring. Mining methods, layouts and rock support systems will be adjusted accordingly to mitigate the risk of rockbursts. Boreholes are routinely drilled ahead of mine workings using diamond-impregnated bits. The drill core is logged to identify lithology and geological structures (especially dykes and faults that may be seismogenic), sample the ore body for grade control, and detect areas that may contain water and/or flammable gas. Methods and technology to improve the efficiency of drilling and maximize the information obtained from the drilling process, borehole core, and the borehole itself are being investigated. A range of geophysical technologies are being developed to map the rock mass from the skin of the excavation to a distance of several tens of meters. Light Detection and Ranging (LiDAR) is used to map the geometry of the excavation, including prominent joint, vein and fracture sets and the presence and performance of rock support elements and systems. Ground Penetrating Radar (GPR) is used to penetrate deeper into the rock mass and image joints, fractures bedding planes that influence the stability of the hanging and side walls. Image processing techniques known as ‘seismic attributes’ are being applied to the radargrams to improve interpretation. Electrical Resistivity Tomography (ERT) and various active and passive seismic techniques (e.g. Tunnel Seismic Profiling (TSP), ambient noise tomography) achieve even greater penetration into the rock mass. Finally, machine learning is used to improve the processing and interpretation of seismic and radar data.

Apr 26, 2022

Tables

Jan 1, 1973

By S. L. Barua

An industrial engineering and computer simulation study was conducted on reclamation operations to evaluate the possibility of integrating mining and reclamation operations, and to evaluate the factors which influence the production potential of scrapers. The study was done in a southern Illinois strip coal mine producing approximately 2.27 M metric tons (2.5 million short tons) of clean coal annually. The main outcomes of this study are (a) it is possible to reduce reclamation cost about 20-25 percent by integrating reclamation and mining operations, (b) haul distance has the most significant effect on scraper production, (c) push-pull is the best mode of operation for wheel scrapers for topsoil/subsoil removal, and (d) historical data obtained from the mine for one year show that average dozer productivity in rock grading is about 60 percent lower than the expected production; similar data for scraper is about 25 percent less.

Jan 1, 1981

By T. Y. Yan

The various ion exchange reactions occurring during the restoration of formations contaminated with ammonia during in situ uranium leaching are reviewed. Data are presented on the restoration of a previously leached laboratory packed column using line saturated brine. Although this restoration fluid selectively and effectively removed the ammonia, 24.5 pore volumes are required to reduce the ammonia concentration from 500 to 3 ppm. The presence of NaCl in the restoration fluid is beneficial in + improving the selectivity of the system for NH removal and reducing ca++ ion consumption.

Jan 1, 1982

By Yi Luo, FENGLIANG WU

Mine gob has long been a safety concern in the coal industry due to the air flowing through the gob area. Therefore, knowledge of the airflow distribution and locations of hazard zones in longwall gob is important to prevent and control these hazards. Due to the inaccessibility of mine gob, many numerical studies have been performed to simulate gob air leakage using computational fluid dynamics (CFD) programs, but most of the studies isolated the gob from the mine ventilation network (MVN) with only predefined pressure boundary conditions. The MVN is, in fact, not static in a dynamic longwall mining process, and it consequently changes the boundary conditions and the gob flow field (GFF). Therefore, the MVN should be incorporated in the CFD model to prescribe the transient boundaries. However, it is very challenging to couple the 1D MVN and the 2D/3D GFF to make the mine ventilation simulation realistic. This research uses a proposed novel finite tube method (FTM) to couple the MVN and GFF. In the FTM, the GFF is discretized into a finite number of flow tubes, each of which is formed by two adjacent streamlines. These tubes connect the MVN into a new coupling network. Based on the FTM, a model for gas migration in gob is established for delineating the hazard zones of explosive methane concentration and spontaneous combustion.

By Siddhartha Roy, Hemant Agrawal, Ram Madhab Bhattacharjee, Devi Prasad Mishra

The paper addresses heat stress in underground coal mines, which poses significant threats to miners’ health, safety, and productivity. It involves a comprehensive ventilation survey in three deep and mechanized underground coal mines in India. Using VentSim software, 3D simulation models were developed to predict heat stress conditions and explore the application of auxiliary ventilation and spot coolers to reduce heat stress.

Oct 1, 2023

By R. Bruce Sheibach

The Picher Mining District, located principally in north-eastern Oklahoma, was one of the world&apos;s largest lead-zinc mining areas during its 55 year life. The field covers an area of approximately 72 square miles (186 km.-); an estimated 1.6 x [103 yds3 of material (1.22 x 103m3)] worth in excess of one billion dollars, has been mined. Mining activities were typified by surface exploratory drilling identifying ore distribution and extension of underground workings to the lead and zinc deposits outlined. Exploration holes were either left unplugged or plugged at the surface with a section of a telephone pole. Low grade ore and waste rock were discarded in mined out portions of drifts. These waste piles containing pyrite and marquisette were left underground and oxidized during the many years of active mining. Upon cessation of mining activities in the mid-1960&apos;s, the drifts and shafts of the abandoned workings began to flood as the cone of depression filled in, leading to the dissolution of the oxidized sulfides and the formation of large volumes of acid mine water in the mined out openings. The resulting poor quality water, with high concentrations of cadmium, iron, lead and zinc, began discharging at the surface in 1979. Contamination of the underlying aquifer supplying local residents was first detected on a localized scale in 1980. The present surface water and ground water contamination have lead to the area being classified as one of the top ten hazardous waste sites in the U.S. by the EPA under the superfund program.

Jan 1, 1982

By Richard Klimpel

The influence of selective chemical dispersants on the hydrocycloning of a copper ore slurry is illustrated. In the % solids and slurry feed rate ranges associated with industrial practice, desirable changes in both d50 and Sharpness Index values of classification were measured with the use of chemical as compared to tests with no chemical usage.

Jan 1, 1981

By T. A. Oberhellmann

The Wobbler Feeder is a comparatively new materials handling and separating device. It is essentially a materials separating or scalping machine, particularly adaptable to separation of oversize particles from mine-run ore and to the separation of oversize materials from overburden, where the removal of oversize materials is necessary, as is the case in conveyor stripping. In construction, the Wobbler Feeder is simply a set of transverse bars of manganese steel, or other wear-resisting alloy steel, each having an elliptical cross-section with the major axes of adjacent bars displaced by ninety degrees so when rotating in unison, the pre-determined space between the bars remains constant.

Jan 1, 1959