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By Jos. Kalbhenn

PART of the plan of re-allocation evolved by the engineers of the Dominion Steel and Coal Corporation in 1932 to retard the rapid advance of the submarine workings seawards was the opening of Dominion No. 20 Colliery, in the Harbour seam, by a pair of cross-measure tunnels from the workings of an older mine working the Phelan seam, which lies 430 feet below the Harbour seam. The tunnels, 8 ft. by 13 ft. in size, were started away from the old workings of Dominion No. 2 at a point 1.5 miles beyond the shore line and were driven on a rising grade of 1 per cent for a distance of 5,335 feet, tapping the Harbour seam at a point 2 ¼ miles off-shore. For transportation and ventilation, shafts and roadways already existing in the Phelan seam were made use of during the stages of development and up to the present time. One of the two tunnels served as a main haulage road and an intake airway, and the other as a return airway and travelling road. However, as the workings of this new colliery expanded, the need for additional airways arose as was anticipated when the plans for the development were formulated. To meet this need, work was started on October 1st, 1942, to establish a new opening between Nos. 2 and 20 Collieries in the form of a vertical shaft to provide a passageway for the ventilating air current of some 250,000 cubic feet per minute on its return to the upcast shafts in No. 2 Colliery, thus making both tunnels available for intake airways. In the interest of safety, speed, and economy, the shaft was raised from the Phelan to the Harbour seam. It is 20 ft. by 12 ft. in size and, with the exception of three timbered compartments across the narrow end, is untimbered. One of the three timbered compartments housed the ventilating tubing and pipe lines, the centre one served as a cage-way for hoisting men and material during the operation of raising, and the third one contained a ladder way. The rest of the shaft was filled with debris during the period of shaft raising.

Jan 1, 1944

By C Roche, G M. Mudd

The Morobe Province of central Papua New Guinea (PNG) has been mined for gold for nearly a century, although it is only in the past decade that large-scale modern mining commenced. The Hidden Valley gold-silver project began construction in mid-2006 and production by August 2009, and is located in the mountains above Wau in the headwaters of the Watut River. The mine is owned and operated by the Morobe Mining Joint Venture (MMJV), which also owns the Wafi-Golpu project, comprising the Wafi gold deposit and Golpu copper-gold deposit, situated in the Watut River Valley. Together they represent a potential mine of the scale of Ok Tedi or Bougainville or bigger. The MMJV is owned in equal shares by Newcrest Mining from Australia and Harmony Gold from South Africa. Although Hidden Valley was the first large-scale mine in PNG to engineer and build a tailings storage facility, poor environmental management during construction and early operations led to significant erosion of waste rock and sedimentation impacts throughout the ~200 km length of the Watut River. Since then, substantial efforts have been made to improve environmental management, especially waste rock placement and storage and water quality management. While the impacts from the Hidden Valley project appear to be reducing, the saga has heightened concerns by many along the Watut River and across PNG about ongoing impacts from mining.This paper presents the results of an ongoing project in the Morobe Province conducted by the Mineral Policy Institute examining the historical, current and future impacts of mining, including community views, social and environmental impacts and the monitoring and regulation of mining. Overall, there is a clear need to more fully integrate social and environmental issues into life-of-mine planning and go above and beyond regulatory requirements. In this way, some of the lessons learnt – by the community, MMJV and government – can be incorporated before, during and long after mining.CITATION:Mudd, G M and Roche, C, ?2014. Mining in Morobe, Papua New Guinea – impacts, assurance and self-determination, in Proceedings Life-of-Mine 2014 , pp 313–336 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By R. H. Pemberton

"THE Mattagami district of Quebec has, during the past few years, experienced intense exploration by virtually every mining company operating in Canada. As a result of this activity, a number of well-mineralized zinc-copper bearing bodies have been found, some of which will almost certainly go into production. Much of the area has undergone what is now termed ""Saturation Prospecting"" or intense and detailed geological and geophysical surveying, followed by the drilling of nearly all possible bets. Considering only the airborne geophysical surveying, some blocks of ground have been flown by virtually every geophysical instrument which has to date been installed in an aircraft. A list of these different geophysical instruments would include: l. Fluxgate-type total field magnetometers 2. Vertical field magnetometer ,3. Nuclear-precession magnetometers 4. Single-frequency out-of-phase electromagnetometers 5. Dual-frequency out-of-phase electromagnetometers 6. Horizontal component measuring electromagnetometers 7. In-phase and out-of-phase electromagnetometers8. Dip-angle measuring electromagnetometers."

Jan 1, 1961

By AIME AIME

It is with the deepest personal sorrow, and with the regrets of the Steel Company of Canada, that I report to you the death of one of our most valued associates, the late Frank B. McKune, superintendent of the Open-Hearth Department of our company. Many of you will remember Mr. McKune for his long attendance at these meetings, for the intelligent interest he took ill them, as well as for his innovations in steel-production practices.

Jan 1, 1940

By A. Fawcett, B. C. Dyer

Abstract - The basis of the tomographic velocity imaging technique is briefly described and an application of the method to detect and image a cross-section through a chromite pod is presented. Using the chromite application as an example, the relative costs of tomographic data acquisition and processing are compared with those of diamond drilling to obtain similar resolution. A number of different tomographic survey configurations and the potential role of the method in surface and underground exploration are discussed.

Jan 1, 1994

By M. J. Collins

"Autoclaves were first used in the metallurgical industry in 1893 to recover alumina from bauxite. In the 1940s and 1950s, several high temperature and pressure processes were invented in the laboratory of Professor Frank Forward at The University of British Columbia, in parallel with advances in equipment and processes by the Chemical Construction Corporation. Sherritt Gordon Mines Limited enlisted these groups to help develop the nickel sulfide ammonia leach process that was commercialized in 1954. Autoclave processes that have since been commercialized include high-pressure acid leaching of laterites, zinc pressure leaching, and pressure oxidation of refractory gold feedstocks. RÉSUMÉ En 1893, l’industrie métallurgique est la première à utiliser les autoclaves pour l’extraction de l’alumine dans la bauxite. Dans les années 1940 et 1950, plusieurs procédés à haute température et à haute pression sont inventés dans le laboratoire du Pr Frank Forward de l’université de la Colombie-Britannique (UBC) ; parallèlement, la Chemical Construction Corporation fait de grands progrès en matière d’équipement et de procédés. Sherritt Gordon Mines Limited fait appel à ces groupes pour qu’ils aident la société à développer le procédé de lixiviation du sulfure de nickel dans de l’ammoniaque, commercialisé en 1954. Les procédés de lixiviation en autoclave commercialisés depuis incluent notamment la lixiviation acide à haute pression de latérites, la lixiviation sous pression du zinc et l’oxydation sous pression des matières premières de l’or réfractaire.INTRODUCTION Autoclaves are chemical reactors that are built to contain processes taking place at elevated pressure. They are used in metallurgical refineries throughout the world to take advantage of the increased reaction kinetics and different reaction products that can be obtained in aqueous systems above the boiling temperature at atmospheric pressure. The word autoclave comes from the French “auto” and the Latin “clavis” and literally means self-locking—that is, the core distinguishing feature of an autoclave is that it includes a means for pressure regulation (e.g., a pressure relief valve). Denis Papin (Figure 1a), one of the inventors of the steam engine, was the first to make use of a safety valve to control steam pressure. He is credited with inventing the autoclave in 1679. Papin’s “digester” (Figure 1b) was a type of pressure cooker that was originally used to liquefy bones. Most commercial autoclaves are horizontal, multicompartment vessels with mechanical agitation, as shown in Figure 2a; however, the steam-agitated Pachuca vessels used to leach laterite ore in Moa, Cuba (Figure 2b), are also classified as autoclaves according to the self-locking definition provided above."

Jan 1, 2018

By C. A. Pickles, D. K. Xia

"In the last few decades, microwave energy has been widely employed in food processing, rubber and plastics curing, and in ceramic sintering. Recently, the application of micro waves as an energy source in extractive metallurgy has received considerable attention from a number of researchers. During the period from the mid-1960s to about 1988, the majority of the research was focussed on the behaviour of materials in microwave radiation. These research activities will continue to be important, since fundamental data on the interaction of microwaves with materials are vital for the successful application of the technology. Since1990, a number of potential applications of microwave processing have been investigated.These include: pretreatment of ores and concentrates, leaching, reduction, preheating of refractories, heating of slags and waste treatment. In this paper, the interaction of micro -waves with materials of interest in extractive metallurgy are reviewed and potential applications are discussed.IntroductionMicrowaves were first used in 1946 for the heating of materials, shortly after radar equipment was invented during the second world war. It was evident that microwaves were very effective for heating water and the technology was quickly adopted for drying and cooking. Since the introduction of the first microwave oven by Raytheon in 1952, many millions of domestic microwave ovens have been sold annually (National Research Council,1994; Atomic Energy of Canada and Voss Associates Engineering, 1990).In extractive metallurgy, microwaves are in the early stages of development (National Research Council, 1994; Atomic Energy of Canada and Voss Associates, 1990; McGill and Walkiewicz, 1987; Bradhurst and Worner, 1990;Peng et al., 1993). However, there are several reasons for the growing interest in the use of this technology in the field of metals extraction. These include the following potential advantages of microwaves: (1) rapid and selective heating of materials; (2) reactions can be catalyzed because the heating occurs on a molecular or atomic level; (3) clean and controllable energy source; (4) the gas volume is reduced and the atmosphere can be controlled as there are no gaseous combustion products; (5) the material is heated internally in comparison to external heating with conventional methods; (6)the temperature of the refractory can be minimized; and (7) the working environment is improved."

Jan 1, 1997

The National Economic Viewpoint? Any substantial project undertaken by private enterprise would normally be subjected to a Discounted Cash Flow analysis of its commercial viability, and would proceed only if the rate of return was judged satisfactory. A 'national viewpoint' analysis attempts to do the same but from the viewpoint of the community as a whole. The objective is to ensure that those projects are undertaken which yield the best return, economic and social, to the nation as a whole.

Jan 1, 1984

By K. Leutwyler, H. L. Bigelow

Jan 1, 1966

This: symposium was sponsored by the Bureau of Mines, U.S. Department of the lnterior, in order to critically examine the state-of-the-art of sulfide flotation chemistry and to define current and emerging problems that should be emphasized in future fundamental research. The topics covered through invited papers include both reviews and recent research results in the areas of thermodynamics of reagent-mineral interactions; collector adsorption processes; the effects of solid-state point defects on flotation; activation and deactivation phenomena; the electrochemical role of oxygen in sulfide flotation; environmental problems in flotation; and selective flocculation of fines. Papers riving perspectives on flotation research in relationship to our national mineral requirements and the relationships between industrial flotation research and academics are also presented. An edited summary of the symposium follows the papers.

Jan 1, 1980

By Dan Preston, Shane Yanagisawa, Robert Marshall, Don Deere

Geotechnical Baseline Reports often estimate the number of cobbles that will be encountered in terms of volume or weight. These estimates are practically impossible to verify in the field. ClaroVia Holdings in conjunction with Frontier Kemper Constructors Inc. developed Digital Geologist 2.0 to classify and count cobbles discharged from an EPB TBM at the RSC7 project in Burbank, CA. The system worked by using two stereoscopic laser sensors with a global shutter to scan and count cobbles at 12 frames per second. Results of the effort are revealed along with lessons learned and paths for improvement.

Jun 13, 2023

1. Domestic Production and Use: Twelve companies operated 31 primary aluminum reduction plants, three firms accounting for 66% of production. Washington, Oregon, and Montana accounted for 32% of the total production; Gulf Coast States, 25%; Northern States, 29%; and other Southern States, 14%. Output of primary metal in 1973 was valued at $2.2 billion. About 80% of the secondary recovery was from new aluminum base scrap and 20% was from old scrap. Aluminum consumption by 25,000 firms was centered in the East Central United States. Of aluminum consuming industries in 1972, building accounted for 28%; transportation 19%; electrical, 13%; packaging, 16%; and consumer durab1es, 10%.

Jan 1, 1974

By Arne M. Myrvang

Rock stress measurements have been carried out by the Mining Department, the Norw. Institute of Technology (NTH) since 1964. Before that time rock stress measurements were carried out at a few locations by the Swedish professor Hast as early as 1958. From the very beginning the NTH engagement in the rock stress measuring field has been very practically aimed, and we have all the time enjoyed a very good cooperation with the Norwegian mining industry. At a very early stage the industry realized that proper measurements with proper equipment could be a very valuable practical tool. Hence the industry also was willing to grant considerable funds for the education of experts and development of measuring techniques. Since 1964 measurements have been carried out in the great majority of Norwegian mines. During the last years a large number of measurements have also been carried out in connection with hydro-electric power plants, road tunnels etc.

Jan 1, 1981

By Dennis Ofiara, Michael Lewis

An experimental 1.75 meter Shaft Boring Machine was designed and manufactured by The Robbins Company. The drill was used by contractor Drillcon Raise AB to drill test shafts at an SKB underground test facility. SKB is the Swedish authority responsible for safe management of nuclear waste materials. This “SBM1.8” Shaft Boring Machine was used to drill shallow test shafts ingranitic rock at SKB’s Aspo underground laboratory. The drill used a unique vacuum mucking system. The bored shafts were held to very strict tolerances for bore diameter, straightness, and verticality. This drill was launched and operated from a mobile launcher. Headroom and working space were limited. The SBM1.8 drill produced acceptable test holes. SKB will carry out several studies to determine the suitability of this geology, and of this technique, for safe nuclear disposal. In addition to future use at SKB, many applications are foreseen, particularly in the civil construction industry.

Jan 1, 2005

By B. Haimson

A new loading apparatus was fabricated and used to conduct true-triaxial compression tests on KTB amphibolite, a crystalline basement rock. Tests in dry jacketed samples reveal that the intermediate principal stress has a significant effect on the onset of dilatancy and on rock strength, contrary to the implicit assumption made by Mohr-type failure criteria. Failure is induced through a shear fracture that dips steeply in the direction of the least principal stress. Experimental results lead to a new generalized strength criterion in terms of all three principal stresses. Unjacketed KTB amphibolite specimens, exposed to confining fluid, are considerably weaker than the jacketed ones, despite the negligible porosity and permeability. Failure is facilitated by several closely spaced subparallel tensile cracks normal to the least stress direction. SEM analysis suggests that microcracks developed upon dilatancy onset are penetrated and extended by the confining fluid, bringing about the unexpected rock failure mechanism at reduced stress levels. Un nouveau dispositif à chargement fut fabriqué et utilisé afin de réaliser un vrai essai de compression tri-axial sur KTB amphibolite, une roche cristalline du sous-sol. Les essais effectués sur échantillons enveloppés et secs révèlent que les contraintes principales intermédiaires affectent considérablement le début de la dilatance et la résistance de la roche, contrairement à la supposition fondée sur le critère de rupture de Mohr. La rupture est produite grâce à une cassure de cisaillement très incliner en direction où la contrainte principale est moindre. Ces résultats expérimentaux indiquent un nouveau critère de rupture général en fonction des trois contraintes principales. Les échantillons de KTB amphibolites sans enveloppe, exposés à un liquide confiné, sont considérablement plus faibles que ceux enveloppés, malgré la porosité et la perméabilité négligeable. La rupture est facilitée par plusieurs fissures de traction adjacentes et sub-parallèles, normales à la plus petite contrainte principale. L’analyse SEM suggère que les micro-fissures développent suivant le début de la dilatance, elles sont pénétrées et agrandies par le liquide confiné, produisant un mécanisme de rupture de roche inattendu, ceci à un niveau de contrainte réduit. Ein neuer Ladungsapparat wurde hergestellt um real - triaxiale Druckfestigkeitsversuche in KTB Amphibolit, einem kristallinen Grundgebirgsgestein, durchzuführen. Messungen in trockenen, bedeckten Proben zeigen that die mittlere Hauptspannung eine bedeutende Wirkung auf das Einsetzen von Dilatanz und auf die Stärke des Gesteins hat, im Gegensatz zu der impliciten Annahme auf Grund von Mohr-ähnlichen Versagungskriterien. Versagen ist induziert durch eine Scherfraktur die sich steil in die Richtung der geringsten Haupspannung nach unten senkt. Messergebnisse führen zu einem neuen, verallgemeinerten Stärke Kriterium dass auf alle drei Hauptspannungen basiert ist. Unbedeckte KTB Amphibolit Proben, die unmittelbar den umgebenden Fluiden ausgesetzt sind, sind wesentlich schwächer als bedeckte, trotz geringfügiger Permeabilität und Porosität. Versagen wird gefördert durch mehrere, nebeneinander liegende, sub-parallele Spannungsbrüche, normal zu der geringsten Spannungsrichtung. SEM Analyse lässt vermuten dass Mikrobrüche, die sich beim Überschreiten der Dilatanzschwelle entwickeln, durch die umgebenden Fluiden fortgepflanzt und weiter verbreitet werden, und unerwartet, auf Grund der reduzierten Spannungswerte, den Versagungsmechanismus des Gesteins einleiten

Jan 1, 2003

By J C. Volkwein, A D. A Hansen, E Sarver, C Barrett

Ensuring that diesel particulate matter (DPM) levels in underground metal and non-metal mines are maintained below statutory limits is an essential requirement of mine ventilation systems. However, despite the cost of providing ventilation, air ventilation rates are usually based upon models, assumptions, or measurements integrated over long durations rather than actual need. Real-time measurement of DPM, interpreted in terms of mine activity schedules, can offer better ventilation management to keep DPM within regulated levels while controlling costs. This work presents data from three demonstration sites with in-mine applications of an environmental particulate sensor that measured black carbon (BC) as a surrogate for DPM.Aethalometers are a class of environmental monitors that measure the light absorbance of aerosol particles at several optical wavelengths. A model AE33 Aethalometer was operated in three separate mines for periods of two weeks, three months, and seven-plus months, and the data was reported in real time as a concentration of BC. Concentration of aromatic organic compounds, which can indicate other forms of combustion, was also reported. The data was used to:- measure the relative efficiency of a new scale-model DPM air scrubber- determine if ventilation could be reduced in a shotcrete loading facility without compromising air quality- evaluate diurnal and weekly DPM levels in a large-entry stone mine. Instrument data were displayed locally and stored for later downloading in all cases. In one mine, the instrument was connected to a local controller, and in another it was connected to the mine’s underground network so that DPM data was presented in real time to a display in the mine ventilation engineering office on the surface.The results showed that the air scrubber removes from 82 per cent to 95 per cent of the DPM; that DPM produced during shotcrete loading is only a minor part of overall DPM levels; and that wide variations in DPM levels exist in the limestone operation. The DPM monitor operated continuously for extended periods in these underground environments. The only maintenance required was the routine replacement of filter tape, typically on a two-week schedule. A sample diluter, which is currently being tested, could extend the intervals between filter changes. The real-time data output of the Aethalometer is appropriate for direct integration into ventilation-on-demand control systems.CITATION:Volkwein, J C, Barrett, C, Sarver, E and Hansen, A D A, 2017. Application of an environmental ‘black carbon’ particulate sensor for continuous measurement of DPM in three underground mines, in Proceedings Australian Mine Vent Conference 2017, pp 143–150 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 28, 2017

By Frederic Dewey

(New York Meeting, February, 1913) This old and well-known method of determining, silver is, in bullion work, so far superior to the furnace-assay that it is looked upon with reverential awe by many, if not by most, users, and its-ease of execution, with proper equipment, commends it highly where much commercial bullion work on silver is required. The method is so thoroughly well known that a, description of it here may seem to be unnecessary, but many thousands of determinations are annually made by it in the U. S. Mint Service and its practice is there reduced to an art. This is necessary both for the sake of economy of time, acid because high-grade work with it requires constant practice. It is useless for a person who uses it only occasionally to expect to attain high accuracy with it, without spending more time upon a determination than is warranted in a busy commercial laboratory. It is always employed in the Mint service whenever possible, but its chief field is in the determination of silver in standard silver (ingots and coin), which is 900 fine in silver and 100 fine in copper, and I shall first briefly outline its use on this metal and then take up various points in detail, especially as related to the accuracy of the results obtained.

Jan 4, 1913

By A. Lucian Walker

SILVER is not only of paramount importance to millions of people as a medium of savings and to other millions as a medium of exchange, but it is also valuable and useful in industry. Mexico continues to be the largest producer of this metal, followed by the United States, Canada, and Peru. The largest consumers are China and India, which normally absorb about two-thirds of the world's mine production, hoarding it as savings. The imports by these countries exert a powerful influence upon the price, yet neither country is on the silver standard. China having abandoned it in 1935 and India in 1893, when the rupee was definitely linked to the pound sterling. Other nations such as Persia, Ethiopia, Mexico, and many of the South American countries either have been on the silver standard or have used silver as their chief circulating medium, and most large nations use it for subsidiary coins, this use accounting for 20 to 30 million ounces annually. The arts and industries have consumed 35 to 40 million ounces each year.

Jan 1, 1937

By Kenneth L. Cook

From March 1944 to July 1945 the Division of Geophysical Exploration of the Federal Bureau of Mines made magnetometer surveys of some of the principal iron ore deposits of the Iron Springs district, Iron County, Utah. The district comprises a belt about 23 miles long and 3 miles wide. Most of the large ore bodies are found as pods of replacement ore within a favorable limestone bed lying at the margins of three separate igneous intrusions in the district The magnetic surveys were confined chiefly to this geologically favorable zone at the margins. The iron ore is a mixture of magnetite and hematite. The magnetite content of the ore ranges from 14 to 58 percent. Magnetic anomalies of 1,250 gammas or more were usually found over the near-surface ore bodies. About 62,000 magnetometer stations were taken over a total traverse distance of about 300 miles. Outcropping ore bodies were surveyed to determine, insofar as was possible from the magnetic data, their probable length, width, depth, extent, strike, dip, and tonnage. Geologically favorable areas where no ore is exposed were explored in an endeavor to find new ore bodies. Favorable locations were determined for exploratory diamond drilling, both in areas of exposed ore bodies and in areas of newly discovered magnetic anomalies. Forty-five separate magnetic anomalies that indicate the possible existence of ore bodies were observed. Of these, 13 anomalies are caused by outcropping ore bodies of proved commercial size. Five are caused by non-outcropping ore bodies of proved commercial size which were discovered, in whole or in part, as a result of the geophysical surveys. Of the remaining anomalies, which lie in virtually un-tested areas where few or no ore bodies are exposed, six probably are caused by large, unexposed replacement ore bodies, nine are possibly caused by large, unexposed replacement ore bodies, and six are probably caused by unexposed magnetite veins of some small commercial importance,

Jan 1, 1949

This paper presents the near-field rock damage owing to production blasting in limestone quarry in the western region of Japan. The study's purpose is to learn the mechanism of crack development due to blast vibration. In this study, blast vibration's magnitude was expressed with peak particle velocity (PPV) which was obtained based on seismographs recorded database. In attempt to pursue a research's purpose of this study, there were two considerable interests: near-field blast vibration propagation and prediction, and crack observed and prediction. Furthermore, with regards to considerable interest of the study, there were three essential aspects which were challenged, such as: monitoring and interpretation of seismic wave propagation in a rock mass near large explosive charge of production blast scale, measurement of blast rock damage in adjacent to blasthole, and determine critical value of PPV which may produce significant rock damage. In order to determine precision critical PPV, understanding correlation between rock damage with vibration level is firstly important to be done. This paper also discusses how to measure, detect and quantify near-field blast vibration and blast rock damage in adjacent to blasthole.

Dec 6, 2010