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By J. Hindman, E. Moeller

Vermiculite is currently mined from shallow (less than 25 m or 80 ft) surface deposits throughout the world. The largest producers are Palabora Mining of Phalabowra, South Africa (ore stock is a phlogopitemica), Xinjiang Yuli Xinlong Vermiculite of Korla, China, and W.R. Grace of Enoree, SC (ore stock is a biotite mica). Smaller operations are in Australia, Brazil, Russia and Zimbabwe. They also produce vermiculite on a continuous basis but do not export any significant amounts of product to North America. Intermittent and poorly documented production on a minor scale is reported from Argentina, Egypt, India and Uganda. Worldwide vermiculite production in 2004 increased1.7 percent to 432.8 kt (477,000 st). North American production declined, while African and Chinese production continued to increase.

Jan 1, 2005

By H. W. C. Prommel

While Utah remains an unimportant factor in oil production, exploratory drilling was carried on in six widely separated areas, extending from the southwest to the northeast corner of the state. One new gas field, the Last Chance or Starvation Creek anticline in Emery County, and two new gas horizons in the Clay Basin field of Daggett County, were thereby discovered during 1934. Exploratory Drilling South Central Utah Emery County—Last Chance Anticline.—The test of the Ramsey Petroleum Corporation in sec. 18, T.26S., R.7E., on the apex of this anticline (vert. closure 700 ft.; area within closing contour line, as mapped by U.S. Geological Survey, 26,000 acres) encountered gas in the Moenkopi formation of lower Triassic age at depths ranging from 2530 to 2863 ft. The total thickness of sandstone, sandy shale and -limestone beds in which gas was encountered is approximately 50 ft. The well was tested at a depth of 2755 ft., gaging 21,000,000 cu. ft. of gas, R.P. 410 lb. The well is being plugged back to the lowest gas horizon at 2771 ft. from a total depth of 3168 ft. Gas from this well probably will be used for the drilling of a second well structurally lower, to test the oil possibilities of the Moenkopi formation as well as of the upper and lower Pennsylvania formations, of which the latter so far remains untested in South Central Utah. The well was not drilled deep enough to determine more definitely the western margin of the petroliferous Paradox Basin of lower Pennsyl-vanian age of southeastern Utah. Woodside Anticline.—This field, lying immediately northeast of the San Rafael swell, contains, according to maps of the U.S. Geological Survey, 8380 acres within its lowest closing contour line 700 ft. below the apex. A well was drilled by Utah Oil Refining Co. at the apex in sec. 12, T.l9S., R.l3E., during 1924. Gas was encountered in the Moenkopi and Kaibab formations of Triassic and Carboniferous (Permian) age respectively. The flow is estimated at 21,000,000 cu. ft., R.P. 900 lb.,

Jan 1, 1935

Mine pit slopes in the Pacific Rim are a geotechnical challenge because of the complex geology in which they are developed. Mines are currently being fast-tracked to meet the increase in commodity prices, often resulting in some reduction in ground studies and short-cutting of design procedures. In addition, the resources boom means that skilled personnel are in relatively short supply. At a time when mine pits are getting bigger and deeper, and the engineering is getting more demanding, there is an increased demand on managers to effectively implement the work.   Experience both in New Zealand and the Philippines, display the complex range of geological environments in which pits are being excavated. Working in these conditions has shown that successful geotechnical design requires a strong geotechnical model based on sound geology. An appropriate level of investigation and analyses results in a certain level of understanding for the mine design. There is a point where additional expenditure (on investigation and analyses) is not warranted based on the expected minimal impact on decreasing the level of perceived risk on the project. For most projects in our experience the analytical methods and complexity of geotechnical assessment changes increases as the level of knowledge grows.

Jan 1, 2006

By M. Sandin

According to the world bank1, the mining industry consumes up to 11 percent of global energy use. In comparison, 70 percent of mining projects from the six largest mining companies operate in water-stressed regions. To steer the direction of the process industries toward more sustainable practices, more than 40 governments have adopted a price on carbon. This measure includes additional taxes on the use of fossil fuels, trade programs, new standards for renewable energy, energy efficiency mandates, more stringent emissions regulation, carbon offsets, etc. This emphasis is also supported by investors shifting their priorities to reduce risk by focusing on long-term plans, including environmentally friendly operations. The metals and mining industry is at the core of the green energy mix and electrification of vehicles. This new trend creates an astronomical increase in demand for minerals. Under a 2-degree scenario, according to the latest analysis from the world bank, as new energy technologies continue to grow, it is expected that all minerals to double in demand, and the distribution of these materials will depend on their application. • Solar panels, will account for 87% of the aluminum demand, and more than 95% of silver • Wind turbines and geothermal plants will require 98% zinc and 64% titanium. • Solar and wind energy alone will demand more than 74% of the global supply of copper, and this is without considering wiring or other infrastructure to connect the grid • Battery storage accounts for 100% of the graphite and lithium demand. (Hund, 2020) • Other materials, such as nickel and steel, are also projected to more than double in demand as they are cross-technology minerals. These materials require a manufacturing process that is accountable for the emissions proper of the transformation process. It requires that these processes move from a hindsight mode focused on reporting to a forecasting mode based on run-time measurement of GHG emissions. This is a critical first step in companies realizing an economic return for doing the right thing for the environment and their communities.

Feb 1, 2023

By Jane Applegate

This report documents efforts to design, develop and test a training approach which would assist front-end loader operators in the acquisition of skills and awareness to reduce the probability of their involvement in accidents in the mining environment. The goal of this project was to prepare and use (on a trial basis) a training method and materials which would be generally applicable to any loader and surface mining operation while at the same time, be adjustable by mine personnel to meet the specific needs of each mining operation. This effort resulted in the Front-End Loader Training System, a structured, performance-based training approach with diverse instructional aids and classroom and on-machine training experiences. Validation of the System at a large western mine demonstrated the utility and flexibility of the training approach and materials.

Jan 1, 1983

Mineral Processing Education in China

Sep 13, 2010

By C. M. G. Wortley, N. Randolph, I. Ralston, R. D. Beck

The ?AMIRA Metal Accounting Project? had its origin in a workshop held in Cape Town on 1 August 2001, with the title ?Challenges in Metal Accounting and Information Management?, which was organised by the Western Cape Branch of the South African Institute of Mining and Metallurgy. This workshop identified the lack of an accepted set of standard procedures for metallurgical accounting as an industry-wide problem. Discussions which followed this workshop led to the initiation of the AMIRA Project P754, ?Improving Metal Accounting?, in 2003. The primary objective of the project was to provide tools for improving the auditability and transparency of metal accounting from mine to product and to facilitate good corporate governance. The planned deliverables of the project were a series of research projects into aspects of metal balancing in different types of metallurgical operations, a Code of Practice on Metal Accounting, and a textbook on the subject which could serve as a guide for metal accounting practitioners and students studying the topic. An additional planned deliverable was the provision of a new variety of professional experts in metal accounting, through successful completion of the research projects. Researchers were engaged at the Universities of Cape Town, Queensland and Stellenbosch and the project was sponsored by five mining companies, including three of the largest global mining groups. Research Program Eight research projects were undertaken as part of the P754 project and these are described briefly here to indicate the scope of the project. University of Cape Town ?Development of a methodology for measurement network design for metallurgical accounting at Namakwa Sands?. This project was based on the Namakwa Sands Separation Plant, with a data rich environment, and involved the investigation of measurement network design through the use of heuristics and the analysis of complex processing circuits. An industry-wide survey of current practice to facilitate the development of an expert system for plant accounting measurements was carried out. ?Metallurgical accounting design at the Waterval UG-2 Concentrator?. The objective of this project is to develop a model for predicting metal recoveries from the different components of a blended ore feed to a plant. ?Optimal measurement network design for metallurgical accounting at Zincor?. This project provided a hydrometallurgical test case for the design and evaluation of a semi-automated optimal measurement network. University of Queensland ?Quantifying the relationship between mine and mill?. This project involved a case study at North Parkes Mine, in which copper and gold ore is tracked from the pit source to the product, as well as a stockpile modelling study. University of Stellenbosch

Jan 1, 2007

By Lana Alagha, Fardis Nakhaei, Jose L. Corchado-Albelo, Noelia Munoz-Garcia, Michèle Heitz

Sulfide tailings from past and present mining activities are important hosts of critical elements and precious metals. This review paper presented a literature survey on the recovery practices of some critical minerals containing Te from sulfide tailings with a special focus on the physical beneficiation and hydrometallurgical separation methods. Finally, a conceptual framework and possible processing flowsheets were proposed. The findings of this review will be useful for the researchers in the field of geochemistry, mineral processing, and metallurgy to evaluate the separation processes for reprocessing of mine tailings for the recovery of critical minerals.

Feb 1, 2024

By John J. Baz-Dresch

Catalyzed diesel particulate filters (CDPF's) reduce the concentration of diesel particulate matter (DPM) and may reduce the emissions of carbon monoxide (CO) and hydrocarbons (HC) in diesel exhaust. Asamera Minerals' Cannon Mine first installed CDPF's in 1987, and currently has 12 diesel-powered vehicles equipped with CDPF's. The Cannon Mine and the U.S. Bureau of Mines collaborated to evaluate the durability and performance of a CDPF. One of the CDPF's used at the mine was periodically evaluated in the USBM's diesel emissions laboratory after 839, 1,584, and 2,881 h of in-mine service. The objectives of this report are to present results from the USBM's evaluation of this CDPF, to describe the Cannon Mine's experience and cost analysis of using CDPF's, and to make recommendations for the future use of CDPF's. CDPF's improve air quality at the Cannon Mine, but they frequently become plugged and are subject to excessive mechanical shocks and stress, shortening their useful life. Mine records indicate that CDPF's account for 0.8 to 4.9 pct of the vehicles' operating cost at the lVine. CDPF life to date has ranged from 1,671 h to more than 5,992 h. Laboratory tests of the CDPF determined that DPM removal efficiency decreased and regeneration temperature increased over time.

Jan 1, 2010

By J. F. Childs

Montana consists of an Archean crystalline basement overlain by Proterozoic through Cenozoic sedimentary rocks. Igneous rocks range in age from Archean to Pleistocene; the most voluminous magmatism and volcanism occurred during the Late Cretaceous and early Tertiary. The state can be divided into three tectonic provinces whose deformational styles are a function of different bedrock responses to Late Cretaceous-early Eocene compressional tectonism. Several long-lived structural zones have been periodically reactivated since the Precambrian, and were the sites of recurrent magmatism. Regional gold distributions are strongly influenced by the tectonic provinces and structural zones. Lode gold systems in Montana occur in diverse geologic settings resulting from a complex interaction between structure, magmatism, and sedimentary depositional processes. Reserves or resources are known for 19 significant lode gold systems, and additional unannounced discoveries have been made recently. Mineralization ranges in age from Archean to Tertiary. The influence of long-lived structures is apparent at both the regional and deposit scale, and in some cases multiple mineralizing events have been superimposed upon one another. Most Montana gold systems have a direct spatial and genetic association with Late Cretaceous through Oligocene igneous rocks. However, the importance of sedimentary rocks and associated depositional processes should not be underestimated.

Jan 1, 1993

By Antonio Marinucci, Robin Mao

The new Hangzhou West Railway Station, which is currently in the early stages of construction, will be located in the city of Hangzhou, China. To accomplish the ambitious goals of the project, the construction work and station building was divided into three project areas. The original design utilizes 1,580 drilled shafts with diameters of either 800 mm or 1000 mm (32 or 40 inch) to support the new Station and its various ancillary structures. The drilled shafts will be tipped into the moderately weathered argillaceous siltstone a distance between 5 and 15 m (16.5 and 49 ft), resulting in an effective pile length ranging from 35 to 43 m (115 to 141 ft), respectively. For the first phase, approximately 550 production drilled shafts will be installed. Eight (8) sacrificial drilled shafts each with a diameter of 1000 mm (40 inch) were installed to a depth ranging from 50 to 57 m (164 to 187 ft), and were tested to confirm the design parameters used for the first phase, to evaluate the contractor’s installation means-and-methods, and to provide guidance whether redesign is warranted for the subsequent two phases. Bi-directional static load testing was performed using a donut-shaped Super Cell to apply unidirectional axial loads up to 13,200 kN (2,970 kip). This paper will describe the bi-directional testing and select results obtained therefrom. The axial compressive and uplift resistances determined from the testing verified that the available axial resistance of a single drilled shaft exceeded the minimum design requirements.

THE de-silverizing of base bullion at the Port Pirie works is carried out in accordance with the principles of the well-known Parkes process. The base bullion produced by the blast furnace department carries (apart from silver values) impurities, the chief of which are copper, antimony, and arsenic. In order to more clearly indicate the grade of the base bullion, the following analysis, representative of a half-year's production of base bullion, is submitted...Before proceeding with the actual operation of de-silverizing, it is necessary that the impurities, copper, antimony, and arsenic, should be eliminated. This is accomplished in the following steps :- (1) Removal of Coppel - Copper is largely present in the base bullion as dissolved sulphide, and this is removed by liquation in a reverberatory type furnace, of which the following are the essential details :-Working temperature 7500 to 8500 C.Coal consumption per 24 hours 2 tons.The hearth of the furnace is encased in a steel tank 22 ft. 4 in. long by 13 ft. 4 in. wide by 2 ft. 10 in. deep; the bottom of the tank is covered by a depth of composition conforming to the invert :-Cement 39 cwt.Brick dust 8.4 tons.Fireclay 0.6 tons.Sand 0.6 tons...

Jan 1, 1922

By Marcel M. Djivre

The paper will outline the destructive test methods and test procedures including the evaluation criteria currently used at the Materials Testing Laboratory (MTL), Sudbury, Ontario, Canada, a laboratory approved by the Ontario Minister of Labour for the purpose of testing or examining mine shaft ropes or other hoisting appliances. For the evaluation of the mechanical properties of rope samples used in "ultra-deep" single-lift shafts, additional discard criteria used in Ontario, Quebec and South Africa shall be presented. Most of the methods and test procedures currently used at MTL can also be found in the current CSA G4-00 Standard, Steel Wire Rope for General Purpose and for Mine Hoisting and Mine Haulage, published in November 2000. In this latest or sixth edition of CSA Standard G4-00, a new Clause 14 has been added outlining the requirements for in-service destructive testing of steel wire ropes for mine hoisting applications. The CSA G4-00 Standard is also intended for the manufacturing of new ropes, and includes requirements for raw materials and construction features for round strand and flattened strand rope, and locked coil rope in bright and galvanized finish. To-date the Ontario Mining Regulations require only that destructive test of new ropes be performed in accordance with CSA Standard G4-00, but does not require conformity to the Standard, and on the other hand the inservice wire ropes are required to be tested in accordance with CSA G4 and thus require conformity. The author recommends that the Ontario Mining Regulations (and regulations of other mining jurisdictions) be improved in order to ensure quality control in the manufacturing of wire ropes destined for mines in Ontario (and Canada). Also, the author recommends the revision of the CSA G4-00 Standard by the technical committee in order to address manufacturer?s concerns with respect to compliance, and harmonize the Standard with Internationally recognized Standards.

Apr 1, 2005

By G. Deschênes

In the last 4 years, the high price of silver attracted more interest for improving its extraction. Metallic silver and silver minerals require a high concentration of cyanide and show slow leaching rates and poor extraction. This investigation determined the effects of dissolved oxygen, lead nitrate and a pretreatment on silver leaching from slurry containing quartz mixed with metallic silver and high purity acanthite. Stephanite, pyrargyrite and polybasite were also used in the study. The silver minerals were characterized by chemical assay, X-ray diffraction analysis (XRD), image analysis (MP-SEM-IPS) and electron microprobe analysis (EMPA). Increased dissolved oxygen of the slurry produced the fastest silver leaching kinetics. The leaching of silver from high purity acanthite was determined under various conditions and compared to a new process called ?CANMET Enhanced Leaching Process (CELP). For a slurry containing acanthite, a 23% improvement (from 76% to 99%) in silver extraction was obtained with the CELP. In presence of pyrargyrite and polybasite, silver extraction increased from 75% to 90% and 86% to 99% respectively using the CELP. No improvement was obtained for the slurry with stephanite (99% extraction in 72 hours). However, the sliver leaching rate was much faster with the CELP. XPS analysis of individual silver mineral particles showed that CELP leached surfaces were considerably more oxidized relative to the conventional cyanidation leached surfaces. Leaching of two gold/silver ores indicated that the efficiency of the CELP increased with the refractoriness of the sample. Gold extractions were comparable for the two technologies while silver extraction improved up to 5% (70g/t) for the CELP. The final leach solutions contained lower concentrations of copper, which consequently reduces the effluent treatment costs.

Jan 1, 2014

By S. P. Sandoval

Previous research by the U.S. Bureau of Mines demonstrated that nonionic surfactants increased the leaching rate of copper in the flask leaching of chalcopyrite with ferric sulfate if sufficient ferric sulfate was present. This research was continued by the Bureau in Part 2 to further explore the application of nonionic surfactants to the dump leaching of chalcopyrite. A polyoxyethylene lauryl ether was selected as the superior nonionic surfactant tested at 25° and 50° C. The addition of the surfactant increased copper leaching by 116 pct at 25° C and 1.0 pct solids and by 61 pct at 50° C and 0.5 pct solids at Fe 3+ concentrations greater than 1 g/L. At 0.1.0 g/L Fe 3+ and below, the addition of the surfactant produced as much as a 35 pct decrease in leaching. Each of the nonionic surfactants studied was found to be heavily adsorbed by a typical chalcopyrite ore, which poses a serious barrier to the application of nonionic surfactants in an actual chalcopyrite dump.

Jan 1, 2010

By K. M. Connor, O&apos

Variations in overburden geology must be considered in applying subsidence prediction methodologies developed by the U.S. Bureau of Mines (USBM). To characterize rock mass overlying high-extraction coal mines, the USBM utilizes a computer spreadsheet program and modified Rock Mass Rating (RMR) system. The spreadsheet calculates an RMR based on a bed's engineering properties determined from core logs and laboratory tests. An in situ deformation modulus and a bending stiffness are computed for each bed. Stiffness-versus-depth plots identify groups of beds with similar stiffness. Large variations in stiffness between adjacent beds are considered significant horizontal discontinuities where slip is likely. Time domain reflectometry (TDR) is used to verify this hypothesis by measuring shear displacement along such discontinuities. A model of the overburden is built by assuming that a near-surface laminated beam exists above a transition zone in which large plastic slip occurs along horizontal discontinuities. Increasingly thicker groups of beds are modeled to determine the most probable beam thickness based on a comparison with measured deflection profiles. The inverse of maximum beam deflection is an index parameter known as "bridging potential," a single value that incorporates both overburden geology and mine geometry.

Jan 1, 2010

By C. J. Greet

Grinding with an electrochemically inert grinding media (i.e., high chrome white iron) shifts the pulp potentials to more oxidising conditions, increases the dissolved oxygen content and reduces the EDTA extractable iron concentration when compared with milling with electrochemically active grinding media (forged steel). These changes in pulp chemistry produce cleaner particle surfaces, reduce reagent consumption, and increase concentrate grades and recoveries. This paper presents a robust laboratory test program that not only demonstrates the changes in the pulp chemistry, but also provide an indication of the magnitude of the metallurgical improvements that are possible. While laboratory studies are interesting, the proof is in the pudding! So, the paper provides an overview of plant trials conducted at several porphyry copper operations around the world: Newmont’s Cadia and Red Chris Operations, as well as Evolution Mining’s Northparkes Operation. These successful plant trials clearly demonstrate that selection of the right grinding media alloy will yield savings in grinding media consumption and reagent consumption as well as increases in revenue through improved copper and gold recoveries. However, many of the porphyry copper mines on the Eastern Pacific are copper-molybdenum deposits. The paper presents laboratory test results for typical copper-molybdenum operations and extrapolate these numbers to what might be expected should a plant trial occur.

Feb 1, 2025

By Edwin M. Chance

EDWIN M. CHANCE, Wilkes-Barre, Pa. (communication to the Secretary*).-I have read with great interest Mr.. Liebermann's paper reporting dynamometer tests of mine cars and wish to express my appreciation of this investigation. The coal-mining industry needs just such precise study of the problems with which it is confronted.

Jan 10, 1916

By Z. Zhang, M. S. Gonzalez, M. de P. Bueno, P. Holopainen, S. Luukkanen

In an extremely competitive mining industry, onsite experience is a big advantage. Mining education at the universities is mostly focused on theoretical studies without a possibility of practical training in mining sites. Hence, experimental mines suitable for practical education are needed to provide a platform for systematic research and education in industrial scale and for training in real mining conditions. Yet, this kind of mine sites is rare worldwide. Thus, a new educational research project, namely MINETRAIN is introduced in this paper evaluating the transition of the Pyhäsalmi mine in Central Finland from an active base metal mine to a research, educational and training underground facility. The uniqueness of MINETRAIN compared to other test mine programs is that the existing state‐of‐art infrastructure in Pyhäsalmi enables research and training facilities among all disciplines related to the overall mine value chain. Though all the above sound interesting in the context of research and education purposes, in practice Pyhäsalmi will have to become an experimental mine that can be sustainable in the future. Accordingly, a prefeasibility study is being conducted and some preliminary results are presented in this paper. INTRODUCTION Despite being a field of studies that requires practical knowledge and experience, mining engineering education follows the same pattern in most mining universities around the world; consisting of theoretical courses and laboratory-based practical modules (Mischo, 2015). The possibility of having practical training in real mining conditions on actual mine sites or processing plants is limited to none, while the only contact that undergraduate students have with mining operations during their time of studies is usually through short-time internships or visits in the context of educational trips. Yet, real integration between universities and the mining industry may be scarce, which does not help students to observe the actual processes, and thus understand the whole picture of mining operations. Indirect practical training is also possible nowadays that technology is shifting from mechanical to digital, and the use of virtual reality -in the context of Mining 4.0- can provide additional experience to the learning process. However, virtual reality is limited to the visual impression and is also limited in actions (Binder et al, 2018). In any case, when there is not a proper pragmatic view of how the different disciplines link to each other and especially if there is a lack of communication, unfortunately the results could be seen at a later stage in the mines as a poor performance of professionals and workers. Another major challenge for educating specialists in the mining sector is that experimental mines suitable for practical education, where the skills and know-how could be developed and/or enhanced are rare worldwide. Such research and educational (R&E) facilities are practically former metal ore mines that have been transformed into experimental sites. Besides being limited in number, not all facilities of this kind serve both a research and educational purpose.

Jan 1, 2019

By J Seccatore, F Golin, E Munaretti, M Cardu, J C. Koppe, J Bettencourt

Contour blasting is commonly performed by employing linear charges decoupled from the boreholes. This method is common in surface and underground excavations, either for civil or mining purposes. To achieve the best results in terms of rock breakage and respect of the excavation profile, blasting theory suggests that charges should be inserted coaxial to the holes to grant uniform distribution of the explosive energy, therefore obtaining a uniform radius of damage. Nonetheless, due to readiness of operations or lack of availability of specific products on the market, non-coaxial charges are often employed in blasting practice. Non-coaxial charging methods include the employ of high-power detonating cord (40 to 100 g/m), low-power detonating cord connecting small-diameter cartridges (commonly 10 g/m detonating cord priming 1” cartridges) or string loading (a thin layer of bulk emulsion pumped with controlled flow and controlled extraction of the injecting rod). This research focuses on evaluating the effects of the first two charging methods on the quality of final walls in open pit and underground operations. Different drilling geometries and charging configurations were applied to both quarrying and tunnelling blasts. The half-cast factor, the overbreak and the underbreak were evaluated as control indicators. Rock quality designation and rock mass rating were used to classify the rock mass. The research was aimed to push contour blasts to their limits, observing for which geometry and charge configuration the blast lost its design threshold with respect to the final wall for every given rock mass. Results show the operational limits of non-coaxial charges encountered in the rock masses object of this study. In good-quality rock, smooth blasting with decoupled linear charge of 40 g/m can be extended to a spacing S = 22Øf with little or no detectable drawbacks in terms of final wall quality, in contrast with theoretical formulae for the determination of the radius of damage. On the other hand, when the rock is poor, any quality of the final wall is hardly achieved at all, in spite of any care in the details of execution of smooth blasting. It is concluded that any design criterion and theoretical approach modelling the effects of contour blasting cannot ignore the features of the rock mass.CITATION:Seccatore, J, Golin, F, Cardu, M, Munaretti, E, Bettencourt, J and Koppe, J C, 2015. Evaluating the effects of non-coaxial charges for contour blasting, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 267–278 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015