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By J. P. Mogan, E. D. Dainty, A. Lawson

"The toxicity reduction of emissions from two diesel engines by the emulsification of water into fuel oil was investigated to determine the applicability of such systems to underground mining machinery. . The engines studied were: 1) the Deut; F6L7J4, four-stroke, air-cooled, 6-cylinder, V-configuration, indirect-injection (IDl) engine, and 2) the Detroit Deisel Allison Division 8V7JN, two-stroke, water-cooled, 8-cylinder, V-configuration, direct-injection (Dl) engine.The application of emulsified fuel treatment to the two-stroke engine did not prove to be practicable. In the case of the Deutz engine, however, substantial benefit resulted. For a modest J5 per cent water content in the fuel and an injection timing of24° BTDC, approximate reductions of40 per cent in the concentrations of both particulate matter and nitric oxide (NO) were produced. These reductions were accompanied by insignificant changes in other toxic constituents. The net result was an approximate 30 per cent reduction in the over-all exhaust toxicity for typical LHD operation as assessed by the Health Effects Index criterion. This toxicity reduction represents a significant advance from the points of view of an improved underground environment and/or reduced ventilation costs."

Jan 1, 1981

Apr. 9, AIME, Chicago Section, Chicago Bar Assn., 29 S. La Salle St., Chicago. Apr. 11-12, Geological Society of America, Cordilleran Section, annual meeting, University of Arizona, Tucson. Apr. 15, AIME, Morenci Subsection, Longfellow Inn, Morenci, Ariz. Apr. 15-17, AIME, South West district meeting, Jefferson Hotel, St. Louis, Mo. Apr. 17, AIME, Utah Section, New House Hotel; Salt Lake City. Apr. 21-22, American Zinc Institute, annual meeting, Hotel Statler, St. Louis. , Apr. 21-23, Chemical, Metallurgical, and Mining Society, and Diamond Drilling Research Laboratory, symposium on diamond drilling, Johannesburg, South Africa. Apr. 22, Assn. of Consulting Chemists & Chemical Engineers, Inc., general symposium, Hotel Belmont Plaza, New York. Apr. 25-26, AIME, New England Regional Conference, Kenmore Hotel, Boston. Apr. 26-May 11, Liege International Fair, Liege, Belgium. May 4-8, Electrochemical Society, Inc., Spring meeting, Benjamin Franklin Hotel, Philadelphia.

Jan 1, 1952

By P. R. Dugan

Sulfur removal from high sulfur coal has several objectives including: a) reduction of the atmospheric load that contributes to the problem of acid precipitation; b) reduction of ash, which contributes to decreased energy transfer in boilers, as well as ash disposal; and c) alleviation of the social and economic dislocations related to uneven geographical distribution of sulfur in coal reserves. Cost in relation to the value of refined coal will govern the development of an emerging coal refining industry. Estimation of the premium paid by power companies for coal with a low sulfur content is a good estimate of the value that will be added as the result of refining. Estimates of premiums paid in 1984 are $28.65/t ($26 per st) for reduction of total sulfur from 370 to 1% S and greater than $28.65/t ($26 per st) for removal below 170 sulfur.

Jan 1, 1988

By H. H. Schrenk

The purpose of respiratory protective equipment is to prevent the inhalation of harmful or objectionable atmospheres. Although constituents or contaminants that may render an atmosphere irrespirable or objectionable are numerous, they may be classified broadly as follows: I. Gaseous substance: n. A. Toxic. B. Inert (oxygen deficiency). II. Particulate matter (dispersoids). A. Solid. a. Dust (formed by disintegration). b. Pure (formed by condensation). B. Liquid. a. Mist (formed by disintegration). b. Fog (former by condensation).

Jan 1, 1940

By A. Philipp, A. S. Middleton, G. A. Harron, A. B. Durham

"Basal till sampling techniques were used to search for gold mineralization in the Timmins, Ontario area. During 1978 and 1979, approximately 90 overburden sampling drill holes were completed in Murphy and Hoyle Townships to test specific geophysically defined target areas. A conventional tricone dual tube drill system, and a unique retractable tricone/rock coring system were used to various advantages.First pass till sampling at 800 to 1200 ft intervals perpendicular to ice transport direction yielded anomalous gold values in till and carbonatized quartz pyrite-rich bedrock chips, and lateritic soil. Subsequent induced polarization-resistivity surveys defined the areal extent of a pyritic carbonate alteration zone. A second pass till sampling/limited rock coring program evaluated the gold mineralization potential of the alteration zone. Diamond drilling has substantiated the till and bedrock gold anomalies. Further evaluation of this mineralization is currently in progress. IntroductionThis paper describes an integrated geochemical/geophysical gold mineralization discovery case history in Hoyle Township. This discovery is on a property jointly owned (I983) by Canamax Resources Inc. and Du Pont of Canada Exploration Limited. Exploration of the property began in 1978 by Rosario Resources Canada Ltd. and in 1979 a joint venture agreement was signed with Du Pont of Canada Exploration Limited. Rosario Resources Canada Ltd. was taken over by Amax Minerals Exploration in 1981, which became Canamax Resources Inc. in 1982.The work described in this paper deals with a gold mineralization discovery located three-quarters of a mile northwest of the gold deposit currently being readied for underground exploration and development. Further drilling is required to investigate the economic potential of the gold mineralization herein described."

Jan 1, 1987

By S. Y. Tshipeng, A. T. Kaniki

"RÉSUMÉ La lixiviation acide d’un minerai oxydé cupro-cobaltifère en milieu non réducteur et en milieu réducteur en utilisant le Fe2+ et le métabisulfite de sodium (SMBS) a été étudiée et les résultats ont été comparés. Les tests de lixiviation ont été effectués à température ambiante, dans une pulpe à 30 % solide, avec une vitesse d’agitation de 600 tr/min, un potentiel redox de 350 mV pour les tests en milieu réducteur, et un pH de 1,8. Les tests de lixiviation avec usage du SMBS comme réducteur ont donné la meilleure cinétique de lixiviation du cuivre. Pour le cobalt, c’est l’usage du Fe2+ qui a donné la meilleure cinétique de lixiviation. L’augmentation de la dose du fer dans la solution au-delà de 5 g/L a influencé négativement les rendements de lixiviation du cuivre et du cobalt. ABSTRACT Acid leaching of a copper-cobaltiferous oxide ore in a non-reducing environment and in a reducing environment using Fe2+ and sodium metabisulfite (SMBS) was studied and the results compa¬red. The leaching tests were performed at room temperature, in a 30% solids pulp, with a shaking speed of 600 rpm, a redox potential of 350 mV for the tests performed in the reducing environment, and a pH of 1.8. The leaching tests using the SMBS as a reducing agent produced the best copper leaching kinetics. As for cobalt, the best leaching kinetics was achieved using Fe2+. An increase in the amount of iron in the solution above 5 g/L negatively influenced copper and cobalt leaching yields. INTRODUCTION La République Démocratique du Congo (RDC) est un pays reconnu dans le monde pour son sous-sol qui regorge d’énormes quantités de cuivre et de cobalt (USGS, 2014; Palisade Research, 2016). La technique qui semble être la plus recommandée pour extraire à la fois le cuivre et le cobalt des minerais oxydés cupro-cobaltifères est la lixivia-tion acide en milieu réducteur. Cette technique est appliquée par la majorité des sociétés minières qui exploitent ces minerais dans l’ex-province du Katanga en RDC, à savoir: Tenke Fungurume Mining, Mutanda Mining, Kamoto Cop¬per Company, Sicomines, Gécamines, Boss Mining, Chemaf, Ruashi Mining et Somika. L’usage d’un agent réducteur est indispensable pour l’obtention d’un bon rendement de lixiviation du cobalt. En effet, plusieurs chercheurs s’accordent sur le fait que le cobalt trivalent de l’hétérogénite (CoO·2Co2O3·6H2O) est insoluble à l’action de l’acide seul; il ne devient soluble qu’après réduction en cobalt bivalent (Mwema, Mpoyo, & Kafumbila, 2002; Mulaba-Bafubiandi, Ndalamo, & Mamba, 2007; Ferron, 2008; Seo, Choi, Kim, & Tran, 2013; Stuurnam, Ndlovu, & Sibanda, 2014)."

Jan 1, 2018

By S. L. Weber, D. E. Banks

"Silicosis was first reported by the ancient Greeks and is apparently as old as human history. The prevalence of this illness peaked in the last half of the 19th century and the early part of this century, when mechanized industry was developing and the relationship between dust exposure and disease was less well understood. Yet, even today in devel-oped countries, sporadic outbreaks of silicosis occur when workers are consistently exposed to silica particles of respir-able size (0.5 to 5.0 µm in diameter) at levels exceeding those recognized to be safe.Silicon dioxide or silica. is the earth's most abundant mineral. Silica is considered to be either free (i.e.. unbound to other minerals) or combined. Minerals with high amounts of free silica include quartz (including granite) flint. Chert, opal, chalcedony, and diatomite. Combined forms of silica are called silicates and include, among others, asbestos talc and kaolin.In the crystalline form, silica exists as quartz, cristobalite, and tridymite (Fig. 28). Of these quartz is ubiquitous in the environment and occurs as sand and as a part of many rocks. Cristobalite and tridymite occur naturally in lava and can be formed by the heating of quartz or amorphous silica. Cristo-balite is more tibrogenic than quartz. Amorphous silica is noncrystalline and, therefore, is relatively nontoxic and does not cause silicosis. It occurs as diatomite (skeletons of pre-historic marine organisms) or as vitreous silica (glass), the result of carefully melting and then quickly cooling free crystalline silica. Heating diatomite with or without alkali (a process known as calcining), forms cristobalite and adds the respiratory toxicity of free crystalline silica.There are many opportunities for occupational exposure to respirable crystalline free silica. Some of the commonly en-countered occupations in which the risk of silicosis exists are reported in Table 20.Silicosis. the pulmonary disease caused by the inhalation of silica particles of respirable size, is most commonly cate-gorized by findings on the chest radiograph. The most typical presentations simple silicosis and progressive massive fibrosis appear different radiologically but are grouped under the category of classic silicosis because they are a part of the radiographic spectrum of this illness. Radiographically, simple silicosis appears as small (less than 10 mm in diameter), rounded opacities, typically predominant in the upper lung zones. Progressive massive fibrosis is the result of the coalescence of these small nodular opacities and appears as larger opacities (more than 10 mm in diameter), again typicallydistributed in the upper lung zones."

Dec 1, 1995

By Allen G. Gray

It's not news to you that the United States is highly vulnerable to potential problems in supply of critical and strategic metals, and that these metals - chromium, for example - are employed in important bearing alloys. It's also not news to you that there is a significant challenge to improve durability and life of bearing systems which contribute to conservation as well as productivity. The objectives of this workshop are to identify available technologies and opportunities for new technologies in conservation, substitution, and displacement of critical and strategic metals in bearing systems. These considerations are among the most viable options for reducing vulnerability to a cutoff of chromium and other critical metals and action should be taken to identify and develop those technologies now rather than after a crisis is upon us.

Jan 1, 1984

By Gregg Davidson, Lonnie Jacobs, Brett Zernich, Alan Howard, Robert Pintabona

All Rights Reserved. Printed in the United States of America. Information contained in this work has been obtained by SME, Inc. from sources believed to be reliable. However, neither SME nor its authors guarantee the accuracy or completeness of any information published herein, and neither SME nor its authors shall be responsible for any errors, omissions, or damages arising out of use of this information. This work is published with the understanding that SME and its authors are supplying information but are not attempting to render engineering or other professional services. If such services are required, the assistance of an appropriate professional should be sought. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Any statement or views presented here are those of the authors and are not necessarily those of SME. The mention of trade names for commercial products does not imply the approval or endorsement of SME.

Dec 1, 2014

By S. M. Javad Koleini

Processing of phosphate ore sample was investigated for increasing phosphate content and reduction of its gangue minerals such as carbonates and silicates. Experimental designs were per-formed using Taguchi method. Different flotation methods were investigated for Moundon phosphate ore sample and three methods were used as follow: direct cellophane flotation, reverse calcite flotation and reverse quartz flotation. Because of the sensitivity of cellophane flotation to slime content, prior desliming was carried out before the experiments. Direct flotation experiments carried out and a concentrate contained 23.80% P2O5, 6.88% SiO2 and 72.33% recovery were produced. The achieved P2O5 content in the produced concentrate from reverse flotation of calcite was 26.44% and the recovery was 82.56%. The concentrate products obtained at optimum conditions by direct flotation of phosphate and indirect flotation of calcite were subjected to indirect flotation of calcite and direct flotation of appetite and final concentrates with P2O5 grade of the order of 24.19% and 26.96% were obtained, respectively. It was concluded that one stage direct flotation is unavoidable to achieve a product with low SiO2 content.

Jan 1, 2014

By Corby G. Anderson

Antimony has been utilized by mankind for thousands of years. However, due to recent environmental concerns, antimony is often considered to be an impurity element, Since antimnoy is commonly found in precious metal refractory ore bodies, extraction is essential. The Sunshine Mine in Kellogg, Idaho has recovered antimony from its precious metal tetrahedrite deposits since the 1940's. A plant was initially constructed as a primary antimony source during World War II. This facility also decreased the downstream smelting penalty for the silver copper-lead concentrate and provided an industrial commodity from a potential environmental nuisance.' This paper describes the Sunshine antimony processing- facility. Specifically, the relevant process chemistries involved in concentrate leaching, metal electrowinning, and sodium antimonate production will be discussed. In addition, ongoing areas of research to improve unit operations and treatments implemented to meet environmental' discharge requirements will be covered.

Jan 1, 1992

This consolidated index covers all publications of the Institute for the years 1926 through 1935. The following list indicates subjects of volumes and gives numbers or abbreviations used to designate them. TRANSACTIONS VOLUME *G26. Petroleum Development and Technology in 1925 (Published in 1926). *G26. Petroleum Development and Technology in 1926. *E27. Institute of Metals Proceedings. 73. Nonferrous Metallurgy, Milling and Concentration, Nonmetallic Minerals, Institute of Metals and Iron and Steel. [ ]

Jan 1, 1936

By R. W. Bruhn

The objective of the study is to examine the apparent influence of soil and near surface rock strata on the severity of damage experienced by surface structures subjected to mine subsidence. The report discusses: 1) modes of ground movement that might complicate or be confused with mine subsidence; 2) prevailing concepts concerning mine subsidence in the Northern Appalachian Coal Field and Illinois Basin; 3) apparent influences of soil and near surface rock strata on the character of subsidence-related ground movements; 4) classifications and criteria for characterizing damage due to ground movements; and 5) types of subsidence damage experienced by homes above active mines in western Pennsylvania. Presented is a damage classification system incorporating a severity index for characterizing subsidence damage to homes with basements above active mines. A series of case histories illustrate subsidence damage to structures above active and abandoned mines.

Jan 1, 1983

At the Prospectors and Developers Annual Convention (PDAC) in Toronto, Canada mining and exploration companies of all sizes were on hand to discuss the year that was and those that will be. The following is a look at some of the companies with Canadian operations that were on hand for PDAC 2009. Iamgold Corporation is a leading mid-tier gold mining company producing approximately 31 t (1 million oz) of gold from seven mines on three continents. With record revenues of $870 million ? up 28 percent when compared to 2007 ? the company is focused on growth with a target to reach 56 t (1.8 million oz) gold production by 2012. During 2008, the company acquired the Essakane project in West Africa. The project is fully permitted, under construction and will contribute more than 9.3 t (300,000 oz) of lower cost production by late 2008. Iamgold increased its reserves by 55 percent, to 385 t (12.4 million oz) and its resources in-creased by 16 percent to 821 t (26.4 million oz) in 2008. Going forward, Iamgold has three areas of focus ? West Africa, Guyana Shield and Quebec ? with seven gold operations, five advanced projects and the Niobec niobium mine included. The Rosebel Mine in Suriname is Iamgold?s fl agship property. With measured and indicated resources of 300 t (9.6 million oz), it accounts for 30 percent of Iamgold?s production. Production there was up 20 percent compared with 2007 and further production increases are expected in 2009 and 2010. Mill expansion and optimization increased throughput from 8.9 Mt/a (9.8 million st) to 10 Mt/a (11 million stpy). In West Africa, Iamgold has joint ventures at Sadiola in Mali; Tarkwa in Ghana; Yatela in Mali and Daman in Ghana. Iamgold also has 100 percent ownership of the Mupane gold mine in Botswana and the Doyon gold mine in Quebec, Canada. Also in Quebec, Iamgold has 100 per-cent ownership of the Niobec niobium mine in Quebec. Niobium is used in high strength specialty steels.

Jan 1, 2009

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 Patterson B. G

The small party of mining men who formed the original Mount Morgan Syndicate in 1882, commenced operations on the top of the mountain with what were practically nothing more than small hillside quarries, It was not until 1891 that underground stoping began, and open-cut mining therefore commenced with the commencement of operations. This hillside quarrying, however, seems to have been quite haphazard and unsystematic ; there is no trace or sign of any properly devised mining scheme. This can be seen plainly enough from an examination of old mine plans; for in less than five years after stoping was; adopted, the open-cut was down into the stoped-out ground. The following table, prepared from these old plans, shows the downward trend of the excavation in the past fiftyseven years:-

Jan 1, 1939

By Basil B. Zavoico

The production of all Russian fields incressed from approsimatctly 74,000,000 bbl. during 1926-27, to approximately 83,000,000 bbl. during 1927-28. Of this amount Baku was responsible for 54,.500,000 bbl., Grozny for 25,800,000 bbl., and Emba for 1,200,000 bbl. Accordingly, the proportional importance of the Grozny oil field has been considerably increased, the present production being twice that of 1913. The most notable factor of production during 1927-28 was the importance of gushers; 40.8 per cent. of the total was thus obtained. In the Baku fields 26 per cent. of the total, and in Grozny 74.2 percent'. of the total were produced by naturally flowing wells. This may be explained by the reduction in authorizations for drilling by the central authorities, and, accordingly, the local trusts increased the production to the planned figures at the expense of the proved prolific reserves. In Baku region, the Surnkany oil field produced 36.1 per cent. of the total Baku production, or an equivalent of 53,800 bbl. per clay, the largest percentage coining from the fifth horizon. Nest year's plans call for continual development of that horizon as well as of the sixteenth horizon in the Bibi-Eibat field, which was opened lately. In the Grozny fields the New Area (Bellik) WAS responsible for 79.4 per cent. of the total production. The authorized plan for 1928-29 production calls for 92,200,000 bid., and a reasonably accurate estimate for 1932--33 production is placed at. 156,000,000 bbl., with Baku contributing 101,800,000 bbl., Grozny 44,100,000 bbl., Emba 6,200,000 bbl., Kuban 2,100,000 bbl., Saghalien Island 1,400,000 bbl., and Russian Turkestan 400,000 bbl. In connection with recent discoverices in the Baku area these figures art. quite conservative. The average production per well per day in the Baku oil fields was 49.2 bbl., in Grozny 175 bbl.; in detail, Surakany oil field averaged 250 bbl., and the New Area in Grozny 514 bbl. per day. New completions in all Baku fields averaged 264 bbl. per day, and in Grozny 970 bbl. pel. day. These figures show a considerable progress in the technical developnlent of all fields, compared even with the prerevolution figures, since all the mprovements are noted in the fields that arc over 30 years old.

Jan 1, 1929

By Oliver Bowles

In 1940 the Bureau of Mines issued a report describing all the cement plants of Latin America, their design, capacity, and output, and the cement imports, exports, and requirements of the several countries. Since that time there has been such great activity in cement plant construction that a revision of the paper is highly desirable. The present compilation comprises the essential data in the previous report together with descriptions of all cement plants completed, under construction, or planned since that date and an overall picture of the supply and requirement situation of each country. Before World War I, Latin America was one of the world's largest export markets for cement. Its dependence on outside sources created no special problems of supply until the shortage of shipping and abnormally high prices of the First World War stimulated a movement toward greater self-sufficiency. Under this incentive many cement plants were constructed, and several countries were able by 1939 to manufacture enough cement for their modest needs. Substantial imports were still required for many important areas, and as the volume of demand was rapidly increasing the Latin American countries as a whole were far from self-sufficient in cement when tine Second. World War began. South and Central America depended to a large extent on European countries, chiefly Germany arid Belgium and to a smaller degree Scandinavia, United Kingdom, France, and Italy, to Supply their cement shortages. The cost of manufacture in these European countries was much lower than in the United States, and transportation expense had been kept at a particularly low level because of the two-way trade that had been developed. Ships destined for Latin American ports for coffee, tropical woods; fruits, and other native products could carry cargoes of cement on their westward voyages at very low cost In some instanced cement was taken in exchange for South American -products because cash was not available. Great Britain had withdrawn from this market to quite an extent because of low prices and because trade with its own Empire had been increasingly fostered. United States trade in cement with Latin America had been confined principally to white and other special varieties. In few places could ordinary portland cement made in the United States compete in price with the European products; although in general it was of better quality and cool d be delivered more promptly.

Jan 1, 1946

By E. C. Demsky

This paper describes the large diameter caisson foundation for the upstream guidewall at the Lock and Dam No. 26 (Replacement) Project. The guidewall is supported on two rows of 1.8-m diameter concrete filled caissons. The 28.8 m long caissons are embedded 15.5 m into the foundation material and have an unsupported length of 12.2 m. This paper describes the philosophy and design decisions leading to this unique caisson design. The construction success and problems for the load test caisson will be discussed. The full scale 13,350-kN caisson load test and the associated lateral load tests will be described and the test results presented.

Jan 1, 1989

By P. D. Rao, D. E. Walsh

Chemical and physical properties of typical low-rank coal (LRC) ash are significantly different than bituminous coal ash. With the exception of extraneous ash, which is incorporated during mining or is due to ash partings within or between coal seams, LRC ash consists primarily of inherent ash that is bonded into the coal's organic matrix or finely disseminated mineral matter. This paper reviews the nature of LRC ash, both inherit and extraneous, and how this impacts the prospects of washing and utilizing LRCs. A literature review, as well as washability data, proximate and ultimate analyses and ash analysis of 25 Alaskan LRC seams are used as a basis for this discussion. The authors' remit research into the nature and distribution of phosphorous in an Alaskan LRC is also discussed

Feb 24, 1997