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By William R. Hardwick

Present information indicates that a copper deposit can be safely fractured with a nuclear explosive and the copper successfully recovered by the in-situ leaching method. The process is not yet at the stage where it can be presented t ) the mining industry as a technique proven in all its aspects, but it is a method with high success potential. Unknown factors must be evaluated by a full-scale test before the economics or the extent of the use of the method by the mining industry can be predicted. Preliminary calculations indicate that the cost of fracturing a copper deposit nuclear explosives may range from l.8 to 55.2 cents per ton or in some case: less than a cent per pound of recoverable copper. Copper may be recovered at less cost than by conventional methods. Deposits with 4 pounds of recoverable copper may be economic and production from a deposit may begin in less than half the time required for conventional methods.

Jan 1, 1967

By E. H. Boyle

The Bureau of Mines has evaluated the potential availability of silver from 436 mines and deposits in 41 market economy countries (MEC?s) comprising five major economic categories of deposits: predominantly silver deposits and predominantly zinc, lead, copper, and gold deposits. This study evaluated the long-term cost and availability of primary silver production from 53 producing and 13 nonproducing predominantly silver properties in 11 MEC's and estimated the total recoverable silver from 370 properties as a coproduct or byproduct of zinc, lead, copper, or gold production. This study resulted in estimates of a demonstrated resource of 5.99 billion tr oz of recoverable silver as of January 1984. Of this total, 23.5 pet is in the 66 mines and deposits classified as predominantly silver properties. The largest quantity of recoverable silver, 43.9 pct, lies in the 121 properties classified as predominantly zinc, with 26.5 pct in 120 properties classified as predominantly copper, 4.1 pet in 21 predominantly lead properties, and 2.0 pct in 108 predominantly gold properties. At current silver prices, the economics of silver production favor silver that is a byproduct or coproduct of zinc, lead, copper, or gold, and much of the silver production in the United States from the predominantly silver mines is at an economic disadvantage in comparison with silver production in other countries.

Jan 1, 1986

By J. S. Hansen

To advance technology that can conserve critical materials, the Bureau of Mines investigated a cast-on hard-surfacing that wear resistance and confines alloy additions to wear-prone surfaces. Wear-resistant material in form is on a polystyrene , the is embedded in a mold of unbonded s and the wear-resistant material is transferred to a cas surface at the time of For low-stress abrasion, derived from high-carbon ferro-chrome had higher wear resistance than did commercially available weld-hard. The microstructure of the was typi-white iron carbides. Free carbon added to the ferrochrome powder produced more M7C3 carbides than did material contained in surfacings made from ferrochrome alone, and improved the wear resistance. Several white iron powders with greatly reduced chromium contents also white iron contain-M7C3 carbides. One derived from white iron powder had wear resistance to that of weld-deposited hard facings. Among the parameters investigated, surfacing thickness was found to have a or influence on diffusion of elements out of the , microstructure, and wear resistance. The results of field tests on bucket-wheel excavator teeth and plowshares with cast-on hard surfacing are given.

Jan 1, 1985

By S. Fletcher, C. Calle, K. Constanti-Carey, R. Ruzbacky, M. D. Horne

Laboratory test-work has established that two classes of redox catalysts based on anthraquinone and bipyridinium derivatives are effective in accelerating the rate of removal of metallic iron from reduced ilmenite (RI) in the aeration step of the Becher process. Two water-soluble anthraquinone derivatives are efficient: 9,10-anthraquinone-2,6-disulfonicacid, disodium salt (catalyst AQ-2,6) and 9,10-anthraquinone-2-sulfonic acid, monosodium salt(catalyst AQ-2). When 0.2 per cent w/v of either was added during aeration the rate of metalliciron removal was accelerated by two to three times. Furthermore, the addition of either compound resulted in magnetite (Fe3O4), the iron oxide phase preferred in commercial practice, being formed. However, both AQ-2,6 and AQ-2 were rapidly lost from solution during aeration although their catalytic activities persisted even when their concentrations in solution were low(<0.05 per cent w/v). The negatively charged anthraquinones were lost from solution most probably by adsorption onto the magnetite that has a net positive charge at the pH values encountered during aeration. To address this problem, the catalytic activities of positively charged bipryridinium derivatives were tested. Two water-soluble bipyridinium compounds, paraquat (1,1’-dimethyl-4,4’-bipyridinium dichloride) and diquat (6,7 dihydrodipyrido [1,2-a:2’,1’-c] pyrazinediiumdibromide), were found to significantly accelerate the rate of removal of metallic iron from reduced ilmenite, and both gave magnetite as the oxide product in the laboratory tests. Moreover, recycle tests showed they were not lost from solution as quickly as were the anthraquinone derivatives. Results in larger scale plant laboratory reactors also showed a significant increase in aerationrates when diquat was added and magnetite was again the oxide formed. However, the oxygensupply to the reactors was insufficient to achieve the maximum effect of the catalysts on theaeration rates. The limited supply of oxygen in a full scale aerator may prevent the application ofthe catalysts in a commercial Becher operation. Keywords: Becher process, aeration, anthraquinone, bipyridinium, redox catalyst, reduced ilmenite

Jan 1, 2003

Major producers posted 25¢-per-pound increases on cadmium, raising their domestic quotes to $2.75 per pound. COBALT: Cobalt consumption in February, exclusive of salts and driers, increased by 21 percent compared with consumption in January. Significant increases in consumption occurred in cutting and wear resistant materials, welding and alloy hard-facing rods and materials, magnetic alloys, and other alloys. The major sales agency for cobalt in New York reportedly announced price increases, effective April 15, 1976, for cobalt metal, powders, and oxide. The new price for 250 kilo (551 lb.) drums of cobalt metal (granules or electrolytic cathodes), f.o.b. Port of New York, was quoted at $4.40 per pound. This is the first cobalt price increase since January 23, 1975, and is the result of a price increase by Sozacom, the official Zairian sales agent. Other cobalt producers are expected to raise their prices in line with the new quote.

Jan 1, 1976

By Jack E. Brockway

As tunnel boring machine technology has expanded, so has its range of application. Tunneling machines (TBM&apos;s) are tackling tasks today that fifteen years ago were considered "inappropriate". A case in point is incline/decline TBM boring. An incline or decline bore presents peculiar design considerations that differentiate it from a horizontal bore. This paper reviews those design considerations as they apply to TBM&apos;s, backup, muck handling and other tunneling subsystems. In addition, several abbreviated case studies are presented. By the review of real life tunneling techniques as well as design considerations, the "appropriateness" of TBM incline/ decline boring today becomes apparent. INCLINE Introduction In contemplating the impact of incline versus horizontal tunnel boring system design, the obvious consideration is gravity. Up-hill boring can be quite different than horizontal boring. Muck, water and machine weight all tend to slide down the incline. In addition, hydraulic and lubrication systems if unaltered, will find their fluids pooled in the lower corners contentedly ignoring such higher elevation items as gears and bearings. In order to address this inherent gravity problem, a review of

Jan 1, 1983

By Charles F. Coleman

Kinetics studies and other rate measurements are reviewed in the amine extraction of uranium and of some other related and associated metal ions. Equilibration&apos; is relatively fast in the uranium sulfate systems most important to uranium-hydrometallurgy. Significantly slow; equilibration-has &apos; been encountered&apos; in some other systems. Most of the recorded rate information, both qualitative and quantitative; has come from exploratory and, process-development development work, while some kinetics studies have been directed specifically toward elucidation of, extraction mechanisms. In contrast to some other extraction systems, relatively little attention has been given to the kinetics of uranium extraction by amines. This is because investigators have not been troubled by slow extractions. Instead, when rate limitations have been of concern in amine extraction (Amex) process developments, they have been mainly from slow phase disengagement rather than from slow equilibration. Nevertheless, taking uranium together with several other elements that are closely related to it or associated with it in typical processes, a considerable body of rate information has been recorded.

Jan 1, 1979

The number of railroad coal cars (open top hoppers), dominated rail car orders and deliveries in 1975 according to announcements made February 11, by the Association of American Railroads and the American Railway Car Institute. Acting to keep ahead of increased coal production, the railroads installed 21,748 new coal cars in 1975, the most since 1957. The 1975 installation resulted in a net increase of 6,560 coal cars and an overall gain of 4.5 percent in the total capacity of the hopper car fleet. With most of the new coal cars going into unit train service --where car utilization is greatest --the railroads actual coal-carrying capacity was increased far more than 4.5 percent. The AAR estimated that unit train operations now move 50 percent of all rail-hauled coal compared to only 42 percent 2 years ago. COBALT - The Societe Miniere de Tenke Fungurume (SMTF) copper-cobalt project in Zaire reportedly was suspended in January for an indefenite length of time. According to officials, the deferment resulted from a number of adverse factors, one of which was exceptional increases in capital costs. The project was scheduled for completion in early 1978, with an eventual production of 14.3 million pounds of cobalt per year. Reserves of cobalt were reported to be 505 million pounds. SMTF is a consortium and includes American, British, French, Japanese, and Zairian interests.

Jan 1, 1976

By Harvey T. Gracely, Mark J. Woodhull

DURING the past few years a marked refinement has taken place in the design of electric power shovels for the mining industry, increasing their digging ability and speed of operation without adding to their total weight. The increase in pay load has been accomplished by a more rigid engineering analysis of shovel design, involving the adoption of new special alloy steels, new sections, and new welding methods. Emphasis has been placed on lightness with increased strength, which is most clearly shown in the front-end equipment where dipper, handle and boom are new in design, material, and construction.

Jan 1, 1938

By Peter K. Kaiser

Planning and design of deep underground mines involves a process of complex three-dimensional data integration utilizing information from exploration (geology, rock mass characteristics), engineering (mining method, excavation geometry, stress) and operations (time, in the form of sequencing). As new logging and monitoring technologies are being developed, the amount and data complexity becomes overwhelming and decisions are often made based on only a small part of the available data. Recently, Laurentian University opened a state-of-the-art Virtual Reality Laboratory (VRL), a Mining Exploratorium that is unique in the world of mining and offers an exceptional data interpretation environment for mine planning and design. The Mining Exploratorium combines a large format spherical stereoscopic projection system, equipped with high definition projection providing the highest resolution of active stereo in the world today, with advanced features of earth modeling software. Combined, this creates the first virtual reality facility geared specifically to the interpretation of mine geometry, geology, geochemistry, microseismicity, geomechanics and mining data sets. This paper demonstrates how value can be added to the mine planning and design process by utilizing this unique tool in the mining decision-making process via better comprehension of spatial relationships of data and by interpreting the data in a collaborative immersive virtual reality environment.

May 1, 2002

By R. W. Brigstocke

History The birth of the mining industry of Canada took place about 1670. According to Salone (Salone E., La Colonisation de la Nouvelle France, page 205) the first discovery of ore in the country was made by an iron-master, Monsieur de la Potardiere, near Trois Rivieres, Quebec. Under French rule some prospecting was done; but at this time no one seemed to consider the working of mines practicable. It was not until the time that Begon became Intendant, when the Marquis of Vaudreuil was Governor, that mining was attempted. Begon was a patron of industrial arts and did his best to promote home manufactures. The mining industry was developed under his regime and discoveries of copper and lead ores were made in 1730. About this time the St. Maurice Forges were erected to treat bog-iron ore, and they were in operation for many years. Prior to 1747, iron pans to the value of £21,000 were manufactured, together with bar-iron and plough-shares. About 1769, that is, ten years after the conquest by Wolfe, stoves and other articles, and, later, potash kettles, appeared. What is still more interesting to us-or was, at least, to General Wolfe-is that cannon balls made at the St. Maurice Forges delayed his operations. A map dated 1744, a copy of which appears in the report of the Ontario Bureau of Mines for 1913 (Vol. XIX), indicates the extensiveness of the wanderings of the French and also shows the location of the lead mine on the east shore of Lake Timiskaming. Bog-iron ore was turned into metal, with charcoal for fuel, at Norman-dale, Norfolk county, Ontario, in 1813, and at Clementsport, Nova Scotia, in 1825. In a volume published in 1672, reference is made to the occurrence of coal on the Atlantic seaboard, and in 1677 Monsieur Duchesneau, the Intendant, levied a royalty of twenty sous per ton on all coal taken from Cape Breton.

Jan 1, 1932

By Willie M. NeSmith, W. Morgan NeSmith, Alan Roach

"In 2013, Augered Cast-in-Place (ACIP) piles are a mature foundation technology throughout the United States. General guidelines for the design and construction of ACIP piles are available along with numerous references for design in specific North American geologies. In fact, the current generation of contractors and geotechnical practitioners might view ACIP piles as just another deep foundation option to be considered, along with driven piles, drilled shafts and others. This acceptance has developed, however, over a 60-plus year period.The term, Augered Pressure-Grouted (APG) pile is often used when referring to ACIP piles because the piles emerged out of construction processes at the Intrusion-Prepakt firm in the late 1940s. The company’s specialty was pressure grouting and preplaced aggregate concrete. The grouting was typically accomplished by driving a pipe to a target level and then injecting grout under pressure. In some soil conditions, it was necessary to use an auger to reach the desired grouting depth. In these circumstances, the grout pipe was driven beside the auger and grout was pumped as the auger was withdrawn. The grout pipe was then withdrawn as well. This was the genesis of the APG, or ACIP pile, and many piles were installed using this technique. The patent application, “Method for Forming Piles” was filed by Raymond Patterson of Intrusion-Prepakt in 1951, and the patent was granted in 1956. The process was eventually modified when a suitable hollow-stem auger was developed. Licenses were granted to the Lee Turzillo Contracting Company and Berkel & Company Contractors, Inc. in the late 1950s. Each of the three companies Patent, LicensesThe patent application, “Method for Forming Piles” was filed by Raymond Patterson of Intrusion-Prepakt in 1951, and the patent was granted in 1956. The process was eventually modified when a suitable hollow-stem auger was developed. Licenses were granted to the Lee Turzillo Contracting Company and Berkel & Company Contractors, Inc. in the late 1950s. Each of the three companies coined their own terms for the piling process: “Pakt-In-Place” for Intrusion-Prepakt, “Auger Pressure-Grouted” for Berkel and “Augercast” for Turzillo. Over time, “Augercast” was frequently used as a generic term for the system. The installation of these piles was, and still is, a highly nuanced process; “contractor dependent” is a term often seen today. Intrusion-Prepakt, Berkel and Turzillo all had personnel who were part of the original group that developed the system and who appreciated the craftsmanship involved in forming sound piles."

Jan 1, 2013

The placer gold industry has experienced a roller-coaster history incorporating four major boom eras. The first, &apos;hand-methods&apos; boom arose in the mid-19th Century from application of an old idea in new places around the globe. The subsequent hydraulic mining, bucket dredging, and &apos;hydraulic excavator-portable plant&apos; booms each arose from application of new ideas in old places around the globe, ie in places where gold had been found during earlier booms. The new ideas that heralded the second, third and fourth booms were all significant advances in excavation technology. These enabled the industry to target the known deposits that were too deep, too wet, too small, or too low-grade for recovery by earlier boom methods. Relatively few new deposits or new deposit styles arose from the &apos;history book&apos; exploration approach, so the number of known deposits to which each of the boom methods were applicable was limited. Consequently, the first three booms were each followed by significant periods of industry decline, and the fourth boom is currently waning inNew Zealand. Further decline is not inevitable and can be avoided by changing to a knowledge-based exploration approach similar to that adopted by the hard rock gold industry in the 1970s. Such an approach could easily herald the next placer gold boom. &nbsp; Most of the relatively coarse, easily won alluvial gold in proximal and medial reaches of the active placer systems is gone. However, a substantial alluvial gold resource remains in the distal reaches of active systems, and in ancient placers formed onshore and on the continental shelf during previous sedimentary cycles. The resource in these deposits probably exceeds the total New Zealand placer production to date. Successful development of these placers requires application of robust geologic models for the formation and distribution of the placers through time, and advanced exploration technology that has not been used before in New Zealand. Nevertheless, the knowledge and technology required to explore and mine these deposits is available now. Many of these deposits contain a large proportion of problematic gold types that are difficult to recover with the commonly used gravity technology without sustaining significant losses. Despite advances in recovery technology in last few years, too much emphasis is placed on the incorrect assumption that gold size is the primary control on recovery efficiency. Other gold particle parameters, especially particle shape, exert a much greater control on whether gold will be saved or lost to the tails, and must be considered in the design of recovery technology and configuration of recovery circuits.

Jan 1, 2003

By Nicholas J. Grant

It is the purpose of this paper to examine a number of the recent developments in powder metallurgy, being most concerned with those which are yet to prove themselves rather than those which have achieved commercial maturity. Such developments include the production of very much coarser and very much finer powders, down to the near-micron size range. Also considered are activated sintering, direct powder rolling and extrusion (both hot and cold), brazing and welding, hydrides of reactive metals, oxide dispersion strengthened alloys and theoretical evaluations. Introduction T HERE surely can&apos;t be very much argument with the fact that powder metallurgy has made large advances on many fronts during the past ten or more years (1). These advances have taken place in raw materials, in processing, in product development and in a better understanding of many of the phenomena which occur in the various steps involved in powder metallurgy. It should be clear, in view of such growth, that it will not be possible to highlight all of the new developments in the present paper. Many of these developments,

Jan 1, 1965

By Xinhua Wang, Qiangqiang Wang, Yubin Li, Shusen Li, Lifeng Zhang

"Numerical simulation on the fluid flow in a Flow-Control Mold (FC-Mold) were performed. The motion of inclusions were calculated. With FC-Mold, the flow pattern and surface velocity become more symmetrical, and at higher casting speed the velocity of liquid steel in the top region of the mold was largely reduced with the highest velocity of the meniscus reducing from 0.65 mis to 0.4 mis, and the meniscus shape became flatter. With FC-Mold, more inclusions approached to the surface of the slab and the amount of inclusion in the center of mold became fewer. Larger inclusions were easier to remove, however, the EM filed of the FC-Mold could hardly improve the removal of inclusions from the molten steel.IntroductionElectromagnetic brake technology is an effective method to control the flow pattern within continuous casting mold, together with other casting parameters, nozzle design and mold geometry [1-5]. Due to the interaction between the applied magnetic flux and the conductive molten steel inside the mold cavity, a force is generated in the direction opposite to the jet flow, which can decelerate the high speed steel jet from the SEN ports. The potential benefits include fewer surface and internal defects, fewer inclusion especially at higher casting speed. However if used imperfectly, electromagnetic forces can have opposite effect [6]. Numerical models are the best tool to optimize electromagnetic flow control. In the current study, numerical simulation was performed to investigate the flow field in a continuous casting FC-Mold, and the effect of different operation parameters on the flow, surface level and velocity in FC-Mold were discussed."

Jan 1, 2013

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&apos;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 S Dunham

A cross-discipline approach combining geology, metallurgy and mine planning, geometallurgy is seen as the next logical advance in improving the design and operation of mining businesses. This rapidly evolving field is focused on realising the value that has often been lost in the chasms between the aforementioned technical silos. When successful, the geometallurgical approach promises the ability to tailor mining and mineral processing development and operational options more closely to the characteristics of the resource with resulting lower costs (both capital and operating), improved recoveries and fewer project failures.As with any technological (or managerial) change, there will be side effects from the success of the geometallurgical approach that will impact areas beyond obvious linkages between geology and processing. Some of these effects have the potential to be beneficial to the resource industry and society in general. Beyond the basic geometallurgical promise of closer alignment between processing design/strategy and the multivariate 3D spatial characteristics of the mineralisation, this paper discusses the broader implications and ramifications of the emergent geometallurgical approach: enhancing exploration and discovery; improving project development success; achieving sustainability in an industry working with non-renewable resources; in a world of increasingly hard won license to operate, improving the management of potentially harmful by-products and waste materials (with knock on effects for proactive management of closure issues); smarter approaches to energy management and thus optimisation of projects with respect to carbon footprint; and potential to re-value assets and thus realise a strategic advantage in the area of acquisitions, divestments, mergers and take overs. The authors strongly believe that companies that actively engage with the above issues (and ensure that technical efforts in the area of geometallurgy are not isolated from the larger value chain activities of the firm) will be able to exploit the opportunities that consequentially arise. These early adopters will gain first mover advantages. Firms taking the broad view of geometallurgy will have an opportunity to maximise stakeholder value and win greater success than their less insightful competitors.

Sep 5, 2011

By Heber E. Peterson, Sill. Claude W.

"INTRODUCTION In the usual volumetric determination of uranium, the solution containing uranium is reduced in a Jones reductor, yielding a mixture of trivalent and tetravalent uranium; the trivalent uranium is oxidized to the tetravalent state by bubbling a stream of air through the solution. The resulting solution of tetravalent uranium is titrated with a standard oxidant, generally sulfatoceric acid, dichromate, or permanganate. It seemed likely that the same general procedure could be used in determining semimicro quantities pf uranium if the conditions affecting the variables involved were understood more clearly than at present. In the method described below, the use of ferric sulfate to oxidize tetravalent uranium allows the titration to be made at room temperature in an essentially colorless solution with sulfatoceric acid. The latter oxidant in turn permits the use of the very stable indicator, ferroin; with its sharp color change and exactly reproducible blanks.Solutions of uranyl sulfate were prepared by diluting a stock solution that had been standardized gravimetrically according to the method of Lundell and Knowles (8).3/ Solutions of sulfatoceric acid were prepared according to the directions of G. F. Smith (12) and were standardized against arsenic trioxide in the presence of osmic acid according to the directions of Glen (5). The cerium solutions were stored in 18-liter carboys fitted with siphon arrangements so that the bottles did not need to be opened and protected from light in a dark cupboard. Under these conditions, even the 0.01 N solution changed by less than 1 part per thousand over a period of about 6 months."

Jun 1, 1952

By Ana Chiquini, Clayton V. Deutsch

The most common approach used in the mining industry for mineral resources modeling is to estimate the grades using ordinary kriging and report the recoverable resources based on this deterministic estimated model. Mineral resources calculated with kriging are a smooth representation of the actual distribution of grades and do not provide an assessment of uncertainty. Unlike kriging, simulation reproduces the variability of the grades in the mineral deposit and provides an assessment of uncertainty. Reporting mineral resources directly on high-resolution simulation results would assume perfect knowledge of the grade at the time of mining and selectivity at the scale of the data. There will always be uncertainty left at the time of mining, so assuming perfect knowledge of the grade in the future is incorrect. There are two concerns when geostatistical simulation is used for resources modeling: the information and the mining selectivity effects. A new framework for resource estimation is proposed with two separate modules to address those concerns. The information effect is accounted for by anticipating the additional production data that will be available at the time mining to guide the destination for the mined material. The mining selectivity effect is addressed by mimicking the grade control procedure to get mineable dig limits at a chosen selectivity, represented by a minimum mineable unit size. In addition to a prediction of recoverable resources that will be closer to the material mined in the future, the framework proposed provides an assessment of local and global uncertainty for risk management.

May 26, 2020

By L. H. Harrison

In coal mines equipped with electrically driven mechanical mining equipment, the problem of protection for electrical circuits and machinery important, because the hazards of fires and explosions resulting from electrical failures is greater than in most other industries. There is need for better methods and improved protective devices for this service. Studies and tests designed to determine possible value of the short-circuiting contactor as an electrical device for coal mine service were investigated. Preliminary made to determine the operating characteristics of the device, after which tests were made under actual service in three coal mines. Ordinarily, electrical protection in coal mines is divided into three classes, as follows: 1. Overload protection that is intended to protect against damage from overheating and excessive mechanical strain due to overloading. 2. Short-circuit protection that provides a means of de-energizing the equipment instantly when an accidental short circuit occurs in the equipment or on the power system. Short cm protection tends to damage from fires and, explosions resulting in the dissipation of large amounts of electrical energy in a short circuit. 3. Ground fault protection that, in its various forms, is intended, to maintain the frames of electrical equipment at or near the same potential surfaces in contact with the earth for the purpose of safe-guarding human life.

Jan 1, 1951