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New York Meets first Wednesday after first Tuesday of each month. J. E. JOHNSON, Jr., Chairman EDGAR RICKARD; Vice-Chairman D. M LIDDELL, Secretary, 7 Wall St., New York, N. Y. C. A. BORN, Treasurer JOHN V. N. DORR - LEWIS W. FRANCIS Boston Meets first Monday of each winter month. R. L. AGASSIZ, Chairman JAMES G. CARLETON, Vice-Chairman E. E. BUGBEE Secretary-Treasurer, -Mass. Inst. of Technology. Cambridge, Mass. W. E. C. EUSTIS G. A. PACKARD Columbia Holds four sessions during year. Annual meeting in September or October. W. H. LINNEY, Chairman OSCAR LACHMUND. Vice-Chairman LYNDON K. ARMSTRONG, Secretary-Treasurer, P. 0. Drawer 2154, Spokane, Wash. STANLY A. EASTON S. SHEDD

Jan 1, 1918

By J. R. Thoenen

[Before 1914 Germany held virtual monopoly on the world supply of potash for fertilizer purposes. During the world War, potash shipments to the United States ceased, and recourse was had to domestic supplies. High war-time prices stimulated interest n various sources, and domestic production increased rapidly. At the close of the war, resumption of shipments from Germany and other sources reduced prices to below pre-war levels, and, as a result, most of the domestic producers ceased operational.]

Jan 1, 1941

By I. Zemanek, A. Rozsypal

Mrazovka tunnel was excavated under one building whose subsurface space was not possible to reinforce against additional settlements induced by digging. In the presented contribution the risk analysis, warning levels and results of deformation measurements are described. Lespace souterrain d‘un des bâtiments sous lequel le tunnel Mrazovka a été creusé n‘a pu être renforcée contre l‘affaissement supplémentaire provoqué par l‘emplacement du tunnel. Le matériel présenté décrit l‘analyse des risques, le niveau des limites et les résultats des mesures des déformations. Der Untergrund eines der Gebäude, unter dem der Tunnel "Mrazovka" ausgeschachtet wurde, war es nicht möglich, gegen nachträgliches Setzen zu versteifen, hervorgerufen durch die Untertunnelung. Im vorliegenden Beitrag sind Gefahrenanalyse, Grenzwerte und Ergebnisse von Deformationsmessungen beschrieben.

Jan 1, 2003

By J. R. Thoenen

[Before 1914 Germany held a virtual monopoly on the world supply of potash for fertilizer purposes. During the World War, potash shipments to the United States ceased, and recourse was had to domestic supplies. High war-tine prisms stimulated interest in various sources, and domestic production increased rapidly. At the close of the war, resumption of shipments from Germany mad other sources reduced prices to below pre-war levels, and, as a result, most of the domestic procedures ceased operations. This experience demonstrated that a domestic source of potash was necessary but that it must be of such a nature that it could compete in price with foreign sources. As a direct result the potash content of thick]

Jan 1, 1941

By D Lalor, N Goodman

The increasing demand for batteries is resulting in the development of large-scale projects for the production of key battery metals such as nickel and vanadium. Several of these projects plan to extract the battery metals from the ore via chemical roasting, leaving large volumes of waste iron oxides after fuming and/or leaching of the battery metals. These iron oxide wastes can be smelted in a HIsmelt furnace using biochar as the reductant, to produce clean, green pig iron with net zero carbon emissions. This green pig iron can then be added to basic oxygen or electric arc steelmaking furnaces to produce green, net zero carbon, steel. This paper describes the flow sheets and the economics for potential projects producing green pig iron via HIsmelt using waste iron oxides from nickel and vanadium production plants.

Sep 18, 2023

By Paolo Cavalcoli, Marco Ziller

"ABSTRACT: In the year 2010 the State of Denmark together with the Municipality of Copenhagen, launched a very important and complex Project : the complete construction of a new double Subway Line :the CITYRINGEN.Copenhagen is the capital with a metropolitan population of 1,9 million.This line is like a ring placed in the very town center which includes all the most historical and monumental buildings and churches, with a total length of 17 km, and the presence of 17 stations plus 4 service shafts.The buildings have been built in the last centuries in an area where the groundwater is near to the surface and there are lakes and channels: the techniques adopted were advanced for those times, but limited as far as regards settlements and resistance to horizontal movements.The soil consists in 2 main groups.1.Upper sediments of the glacial ages : thickness total = 5-20 m composed by clay- silt-sand-gravelcobbles- granite boulders and flint in blocs and in layers : frequency and size of these obstacles wherenot determined.2.Limestone layers : 2a. upper limestone : highly fractured ,highly permeable2b.Itermediate limestone : less fractured, medium permeability.2c. Lower limestone : almost not fractured, low permeability.2d Bryozoan limestone : composed by fossils with microscopic dimensionsIn all the limestone formations there are important layers of flint , having thickness variable up to 3 m and important extensions. Water : in a part of the areas of the Cityringen the water is drinkable and utilized in the public waternet.Pollution: there are polluted zones due to previous industrial activities. Benzene areas have been identified, and for those areas special protections against pollution have been implemented.METROSELSKABET ,the public owner of the Cityringen,has set as priority to operate for the construction of the Cityringen the full protection of the environment and the respect of all the stakeholders :Very strong limits for the exhausted gas emissions have been introduced, by far stronger than those applied from the State of Denmark, very strong limits for the acceptable noise emission. And last but not least very important safety measures and procedure to avoid any accident on site."

Jan 1, 2014

By T. Leißner

This contribution deals with the mineral processing of Li-silicate greisen-type ores comprising of quartz, topaz and zinnwaldite (lithium-rich mica). The origin of the greisen-type ores processed is the Ore Mountains(Germany) where it is explored as a potential resource for the production of lithium carbonate. The goal is to develop a process chain for the enrichment of zinnwaldite using dry techniques only. As basis for the investigation the process chain, which historically was used to process the greisen focused on cassiterite and wolframite, is taken and modified towards the zinnwaldite. Starting with crushed material with particle sizes smaller than 35 millimeters, investigations on different approaches to grinding to liberate mica from gangue are carried out. Concentrates of zinnwaldite are then produced by magnetic separation of size fractions. To assess the success of grinding, classification and separation, mineral liberation analysis and atomic absorption spectroscopy are used. The amount of lithium measured in the sample with atomic absorption spectroscopy was used to calculate the content of zinnwaldite based on its known mineral chemistry. Combined with the particle size distributions, product qualities are determined. Altogether, this allows the thorough evaluation of the success of comminution with focus on following steps of concentration. Keywords: lithium, zinnwaldite, magnetic separation, mineral liberation analysis

Sep 1, 2012

By F. H. Rhines

Page Foreword. By F. N. Rhines............................525 Design Factors for the Metal Forms with Which Powder Metallurgy May Compete. By Fred P. Peters...................... ......527 Discussion..................................530 Powder Metallargy as Applied to Machine Parts. By A. J. LanghamMer........531 Discussion......................... . Pole Pieces for Electric Motors from Iron Powder. By F. V. Lenel...........535 Discussion....................... . Bearings from Metal Powders. By W. R. Toeplitz.................542 Discussion.........................'.........549 Brushes and Allied Powder-metal Parts. By R. R. Hoffman . .............'550 Electrical Contacts Manufactured from Metal Powders. By E. I. Larsen........554 Sintered Magnets. By C. B. Fulton........................557 Friction Articles from Metal Powders. By C. T. Cox..................565 Discussion..................................567 Certain Characteristics of Silver-base Powder Metallurgical Products. By I?. R. Hensel and E. I. Larsen........................ ....569 Discussion............................... . . . . 579 Some Properties of Sintered and Hot-pressed Copper-tin Powder Compacts. By C. G. Goetzel..................................580 Discussion..................................593 The Sintering of Metal Powders—Copper. By C. J. Bier and J. F. O'Keefe......596 Some Experiments on the Effect of Pressure on Metal-powder Compacts. By Jerome F. Kuzmick..................................612 Discussion.................................. 630

Jan 1, 1945

By Gilles Cachia, Foteini Vasilikou, Seth Pollak, Hannes Lagger

"INTRODUCTION The Shatin to Central Link (SCL) is a new rail line being constructed by the MTR Corporation for the Government of Hong Kong to cater for the growing passenger demand between the North-East New Territories and the urban areas of the city. Contract 1103, which will provide the 4 km of running tunnels between the new Hin Keng and Diamond Hill Stations, was tendered in a design-build framework and awarded to Vinci Construction Grands Projets (VCGP) in October 2012, with Arup as Vinci’s lead designer. One of the most challenging pieces of work on the contract involved the construction of 133m of SEM mined tunnel on the northern end of the project. The Northern Mined Section (NMS) is an undrained, twin-track, single bore profile, broken out through the southern pipe pile wall of the Hin Keng Station cut-and-cover box, Figure 1. The tunnel has maximum excavated dimensions of 14.5m span x 12m height, with track spacing of 6.175m. The general excavation sequence consisted of 3 stages; a 6m high top heading (73.1m2), followed by bench (27.3m2), and invert (26.7m2). A risk-based approach to the design was taken given the large variation in rock level, cover, and an active stream course above tunnel crown. Ultimately, six different temporary support types were utilized in order to optimize the construction process through continually changing ground while maintaining a safe and stable excavation. Three main support types were developed during the initial design phase, along with a “contingency” case, which utilized a partial heading excavation sequence and enhanced face support. The purpose of the contingency support type was to have a robust, engineered design available for immediate implementation should unexpected ground behavior develop, leading to the breaching of instrumentation trigger levels. This support type was never implemented on site. Drill- and-blast tunneling commenced once 6m of rock cover was verified through forward probing. A robust instrumentation and monitoring scheme provided valuable data throughout excavation and the means to carry out a geotechnical back-analysis of the ground behavior and support performance."

Jan 1, 2016

By Arthur L. Murray

"INTRODUCTION In compliance with those provisions of the organic act establishing the Bureau. of Mines which relate to improvement of health conditions of persons engaged in the mining, preparation, or treatment of mineral substances, sanitary surveys have been made of towns and villages housing the coal miners, metal miners, and mill and smelter employees of Utah.The purpose of the surveys is to afford studies of conditions prevailing in the various mining and smelter towns so far as concerns housing, water supplies, sewage disposal, refuse disposal the handling of foodstuffs, general sanitation, wash and. change houses, and the control of preventable diseases, all of which directly or indirectly have a bearing on the health and efficiency of employees and their families. Certain other factors have been added to the general sanitary surveys such as school and recreational facilities, which have a decided influence on contentment and efficiency. Through comparisons of favorable and unfavorable conditions and practices, and the dissemination of such information, improvements can be effected which will benefit both the employees and the employers.ACKNOWLEGMENTSAcknowledgment is made of the many courtesies shown by the officials of companies and towns visited. In some instances the towns were entirely under the control of officials of mining companies, being on company property whereas, in other instances, the towns wars incorporated not under company management. Particular acknowledgment is made of the assistance given by the Utah State Board of Health through Health Commissioner Dr. T. B. Beatty."

Oct 1, 1932

By Pablo dos Santos Pina

O alto custo do coque na produção de zinco no Forno Waelz da Votorantim Metais Zinco, em Juiz de Fora, ensejou a realização de testes em parceria com o SENAI CIMATEC para utilização de combustíveis alternativos na Planta Piloto, com o objetivo de mapear a viabilidade técnica e financeira para utilização na Planta Industrial. Ao longo dos testes foram utilizados: cavaco de eucalipto, chip de pneu e moinha de carvão vegetal. Os testes foram realizados com sucesso, apresentando oportunidades de substituição do coque usado atualmente por combustíveis alternativos, com potencial de ganho financeiro para VMZ JF. Este potencial precisa ser validado em testes em escala industrial.

Aug 17, 2017

By Frank T. Sisco

SHORTAGES of metals and minerals and substitution of less critical materials for those in which a virtual famine exists received detailed and frank discussion at a recent conference in Washington called by Robert E. McConnell, director of the Conservation Section, Office of Production Management. Representatives of the large engineering societies in the United States and O.P.M. department heads participated in the discussion. To open the session Mr. McConnell called upon Zay Jeffries, chairman of the O.P.M. Advisory Committee on Metal Conservation and Substitution, to summarize the present situation. Dr. Jeffries touched briefly on the status of metal shortages, which has already received considerable attention in the popular press, and said that much of the present difficulty was caused by the too-hasty substitution-without sufficient con¬sideration of the immediate conse¬quences-of metals having ordinarily a small yearly consumption, for those having a much larger annual consumption. As a result, all the alloying metals used in alloy-steel manufacture have become scarce, with the exception of molybdenum; further¬more, despite a reserve of 11,000 tons of molybdenum in this country and despite a normal consumption of only about 3500 tons and a prospective annual production rate of 21,000 tons by October, a shortage of molybdenum is possible before this war is over.

Jan 1, 1941

By H. G. Moulton

H G. MOULTON should not be confused with the famous economist of the same name. Our H. G. stands for Herbert George, whereas the chief of the Brookings Institution is Harold Glenn. Like most so- called New York members of the Institute's hoard, Mr. Moulton came from the West, in this case from Idaho where he was born, and Oregon, where he was educated at the University of Oregon. His early work included such jobs as mucker, assayer, smelter, chemist, mine surveyor, draftsman, engineer on surveys and construction, and assistant on mine examinations. In 1909 he was engaged as mining engineer by the firm of Eugene Meyer, Jr. S' Co., continuing with them for the next eight years.

Jan 1, 1937

By L Avalos, F Melo Miranda, J Misle, M Ingwersen

"Los Pelambres, majority owned by the Chilean company Antofagasta Minerals, is one of the leading producers of copper and molybdenum in the country. It is located high in Andes Mountains, over 3000 metres above sea level, 316 km from the nation's capital, Santiago.The maintenance service supplied to Los Pelambres over the past 13 years has evolved to the point that FLSmidth now provides an integrated service crucial to the management of their customer's assets. The contract initially involved specialty mechanical, electrical and instrumentation maintenance and has developed to encompass maintenance planning and plant control systems.The integrated partnership has delivered excellent results in the areas of improved availability, reliability and return on investment. The operation is now amongst the industry leaders in plant availability.The integrated maintenance service has delivered: An increase in plant availability from 93%, in the first year, to 96.5% today, generating approximately $50 million additional income per year, Quality work procedures, Process and equipment improvements, Major shutdown planning involving more than 700 personnel, 6000 parts and over 2 000 discrete activities.The ongoing success of the partnership requires a high level of understanding between both companies. A commitment to maintain a long term sustainable relationship, based on a ""win - win"" culture, is the key to this success. In this regard Los Pelambres has been a pioneer in establishing and developing such relationships.This case study will share the lessons learnt, the measures taken to improve performance and the best practices adopted during the 13 year evolution of the maintenance service partnership.CITATION:Misle, J, Melo Miranda, F, Avalos, L and Ingwersen, M, 2013. Integrated maintenance services at the Los Pelambres Mine in Chile - The lessons learnt and best practices developed from a long-term sustainable relationship, in Proceedings MetPlant 2013 , pp 296-331 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Jul 15, 2013

Most of the world' s continental' shelves are .primarily . esozoic-Tertiary phexicmena. Those ,of south,eap- ern Australia are' no exception, although cam-plicated by possible TTmelon-seed" type block upthrusts in the region of the Bass Strait (e.g. King Island, Wilson's Promontory etc.) These terraces represent the progressive infilling and seaward. outgrowth of enormous volumes of tern g_enous sediments into the marine environment. Asa consequence they constitute the preferred habitats, of, petroleum.The Gambier ,sub-basin forms part of the southern Australian-continental terrace where it opposes the (3000 fathom), Jeffrey deep. The'purpose of'this paper is to discuss its nature, structure,_ and developmental history in re-lation to its oil prospects.

Jan 1, 1962

Mineral deposits of the central New Guinea region (Gunung Bijih, Ok Tedi, Mount Kare, Porgera, Frieda River) and of southeastern New Guinea (Wau-Edie Creek, Wafi, Hamata, Hidden Valley, Tolukuma, Misima) are associated with hot, forceful intrusions of magma of mantle origin that penetrated thick Precambrian and Palaeozoic continental crust. The interaction of high- temperature melt with continental crust, and the differentiation of melt while in transit through thick crust, may be factors in generating ore. Mineralised intrusives in central New Guinea are a result of Neogene- Quaternary magmatism and were emplaced in a foreland thrust belt environment, a setting similar to the (mineralised) Laramide intrusions of southwestern USA. In both cases, central New Guinea and the Laramide, magmatism is not obviously subduction- related. Mineralised intrusives in south- eastern New Guinea (Wau-Edie Creek, etc.), also, are in a thrust belt setting, and are not obviously subduction-related. The association of. gold in southeastern New Guinea with a second (Pliocene) phase of igneous activity, rather than with earlier (Miocene) activity suggests that re-working by successive intrusions may be a factor in localising ore. This is seen, also, in the Bismarck-Solomon islands region where the richer deposits are associated with later (Pliocene) intrusives rather than with earlier (Eocene-Oligocene) intrusives. Unlike the mainland mineral deposits, those of the Bismarck-Solomon islands are clearly subduction-related.

Jan 1, 1991

By Bulters J, Sheppard I

Two blasthole density logging programmes have been conducted on the Mt Whaleback iron ore mine to evaluate the use of this type of logging as an aid to blast pattern design. The first programme also involved the setting up of a Density Test facility with which to calibrate the density probe. The programmes indicated that about 22-23 blastholes can be consistently logged per day at a cost of $1.30 per metre. Even though this is only half the rate required to log the average number of blastholes drilled daily on Mt Whaleback, testwork indicated that no significant loss of accuracy results if only half the holes in a pattern are logged. The major results of the programmes were: 1. The density range for black pyritic Shale is 2.2-2,9 g/cc. 2. The density range for soft to medium hard BIF is 2.1-3.0 g/cc. 3. The density range for hard BIF is 3.0-3.6 g/cc. 4. The front row blastholes show consistently lower densities than the main body holes due to blast damage. 5. A low density zone extending to a maximum depth of 6 m occurs at the top of most blastholes and results from blast damage from the bench above. These density results have been used to implement savings in drilling and blasting via pattern expansion and charge optimisation of blastholes. Eight ore

Jan 1, 1986

By C. Alvarez del Villar

"El presente trabajo describe algunos estudios realizados sobre las condiciones ambientales en operaciones de subsuelo, en 30 minas peruanas. Dichos estudios comprenden un período de 10 años (1949-1958) donde se evaluaron los riesgos de contraer silicosis en las zonas mineras, así como aquellos análisis relacionados con las operaciones de subsuelo. La gran mayoría de minas evaluadas están ubicadas en la región de la Sierra (Junin, Pasco, Huancavelica, Cajamarca), mientras que la minoría en Arequipa, Puno, La libertad y Lima, cuyas alturas oscilan entre 1000 y 4800 m.s.n.m. Los resultados de la concentración de monóxido de carbono señalan que de las 20 minas examinadas, solo 8 dieron un 100% de detecciones por debajo del límite permisible. Mientras que del 12 restante, la concentración del gas permanecía luego de un tiempo de dos horas. Por ende, existe una mayoría de centros mineros donde no se concientiza el riesgo de salud sobre estos niveles de monóxido, y tampoco se ejecuta los principios de ventilación por dilución como el mejor medio de evitarlos. Bajo estas circunstancias nace la silicosis, enfermedad producida por la producción de partículas de sílice libre depositada en los pulmones. En 1935, Cummings propuso como primer criterio de riesgo, la relación de la exposición del polvo con la cantidad de sílice libre y a partir de allí, se adoptaron medidas basadas en este primer criterio de ""exposición-respuesta"", encontrándose que el valor máximo del sílice libre está en los minerales de cuarzo, incluso cinco años antes de su exposición. Mientas que la relación alternativa de ""dosis-respuesta"" es más factible en los tres estadíos de la silicosis, tanto en el sentido de sus concentraciones, como en el número de años de exposición."

Jul 20, 1959

New York Meets first Wednesday after first Tuesday of each month. J. E. JOHNSON, JR., Chairman EDGAR RICKARD, Vice-Chairman D. M. LIDDELL, Secretary, 7 Wall St., New York, N. Y. JOHN V. N. DORR C. A. BOHN, Treasurer LEWIS W. FRANCIS Boston Meets first Monday of each winter month. R. L. AGASSIZ, Chairman JAMES G. CARLETON, Vice-Chairman E. E. BUGBEE Secretary-Treasurer, Mass. Inst. of Technology, Cambridge, Mass. W. E. C. EUSTIS G. A. PACKARD Columbia Holds four sessions during year. Annual meeting in September or October. W. H. LINNEY, Chairman OSCAR LACHMUND, Vice-Chairman LYNDON K. ARMSTRONG, Secretary-Treasurer, P. O. Drawer 2154, Spokane, Wash. STANLY A. EASTON S. SHEDD

Jan 9, 1917

By G de Jong, W Sunyoto, K Sari, P Silalahi

"An EXTENDED ABSTRACT is available for download. A full-length paper was not prepared for this presentation. The Big Gossan mine is operated by PT Freeport Indonesia and is one of the largest stope-and-fill mining systems in the world. The Big Gossan deposit is a ~200 m wide, 1200 m long and 500 m high steeply north-east-dipping to subvertical skarn body at the Cretaceous-Tertiary Ekmai-Waripi contact. The copper-gold mineralisation, with a 1.3 per cent copper equivalent cut-off grade, occurs mainly proximal to the Ekmai-Waripi contact in the garnet-clinopyroxene prograde skarn at the base of the Tertiary Waripi formation and partly distal to the contact in the tremolite-actinolite retrograde skarn of the Tertiary Waripi formation.The Big Gossan stope mine is designed from 2540 m to 3020 m above sea level. Present active stoping operations occur at level 2540 mL to level 2640 mL and are done in a primary and secondary stoping sequence. The width and length of the stopes is 15 m and 20 m respectively, while the height of the stope varies between 20 m and 40 m, depending on the ground conditions. The stability of the stopes is visualised in the Mathew’s Stope Stability graphs. These graphs and actual Cavity Measurement Scanner measurements on the stope will predict and show the overbreak and underbreak, which affect the reconciliation of the mined stope and also the pillar stability between the primary stopes. Geological factors like major structures, joints, veins and alteration intensity are important factors that correlated with the stability of the Big Gossan stopes.CITATION:Sari, K, de Jong, G, Silalahi, P and Sunyoto, W, 2015. Stope stability at the Big Gossan skarn deposit, Papua, Indonesia, in Proceedings PACRIM 2015 Congress, pp 139–146 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 18, 2015