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By M Sciortino, J Korczak, J Muinonen, A St-Jean

The Dumont deposit is a large (1179 Mt reserve), low-grade (0.27 per cent nickel) nickel sulfide project located in the Abitibi region 25 km west of Amos, Quebec. Royal Nickel Corporation (RNC) acquired the project in 2007 and has since taken the deposit through to feasibility. The disseminated nickel sulfide and alloy mineralisation is hosted within the serpentinised dunite subzone of the Dumont Sill; a differentiated, pervasively serpentinised, ultramafic sill of komatiitic affinity. Pentlandite ((Ni,Fe)9S8), heazlewoodite (Ni3S2) and awaruite (Ni2.5Fe) are the dominant nickel-bearing metallic phases and can be recovered by conventional methods (flotation, magnetic separation). Non-recoverable nickel is also present within serpentine and olivine of the silicate matrix.A detailed mineralogical program including 1420 QEMSCAN« samples and 4400 electron microprobe points was undertaken to increase the understanding of the nickel deportment in the various recoverable and non-recoverable phases in a spatial context across the deposit. A total of 105 metallurgical tests have been performed under a standard procedure which have linked the mineralogy to metallurgical performance. This has allowed the creation and modelling of geometallurgical domains on a block-by-block basis to understand the recovery variation and metallurgical performance throughout the deposit. Understanding the spatial variability of Ni deportment in recoverable and non-recoverable phases through mineralogy is the key to understanding metallurgical performance, thus unlocking the value of the Dumont deposit and other large tonnage low-grade ultramafic nickel deposits.CITATION:Sciortino, M, Muinonen, J, Korczak, J and St-Jean, A, 2013. Geometallurgical modelling of the Dumont Deposit, in Proceedings The Second AusIMM International Geometallurgy Conference (GeoMet) 2013 , pp 93-100 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 29, 2013

By H. L. Riley

Cleaning and handling of fine coal are generally conceded to be more difficult problems than preparation of the coarser sizes. Increased mechanization in the coal-mining industry has, in general, resulted in an increased percentage of the fine sizes in the total coal mined. If the coal fines are cleaned by wet methods, the minus-1/16-inch square-mesh particles cause most of the sludge and slurry problems encountered in preparing wet coal. Equipment that separates coal from refuse on the basis of specific gravity is not efficient on sizes that, because of their fineness, do not follow the same laws of hindered settling as the larger particles. Probably the best solution of fine-coal cleaning problems is to use other methods, such as flotation, that utilize other physical characteristics than those determining hindered-settling ratios. Regarding the type of flotation known as the Elmore vacuum-flotation process there has been a scarcity of data and information available in this country. An investigation has therefore been made to obtain additional date and information on this process under laboratory conditions. During this investigation an effort has been made to evaluate the relative efficiencies of vacuum and mechanical laboratory froth flotation cells. The investigation included float-and-sink, screen-sizing, and flotation tests on 2 different samples of 14-mesh to 0 raw coal and an a sample of slurry from the settling-tank overflow of a typical washer. One raw-coal sample was obtained from the American bed and represented a type of coal that is relatively easy to clean. The other raw-coal sample was from the Mary lee bed and represented a type considered difficult to clean.

Jan 1, 1954

By Pedro Henrique Vasconcellos Apipe

O objetivo do trabalho consistiu em estudar os modos de transmissão de calor existentes em um conjunto mecânico composto por um rolo de extração e mancais de contato rolante em decorrência do movimento de um tubo laminado sobre o mesmo na planta da Vallourec Brasil. A motivação para o estudo surgiu na avaliação de como os fenômenos térmicos presentes resultariam na distribuição de temperatura através da superfície do conjunto e qual a sua relação com a disponibilidade desse equipamento. Para isso a análise desenvolvida foi baseada no emprego da dinâmica dos fluidos computacionais (CFD), associada a imposições subsidiárias durante a definição das condições de contorno do problema. Como resultado a distribuição de temperatura através da superfície do conjunto foi determinada, sobretudo na pista interna do rolamento e na região na qual se encontra o sistema de refrigeração. Desse modo conclui-se que embora o sistema de refrigeração dissipe uma grande quantidade de calor a sua eficiência não é satisfatória. Fato esse descrito pela presença de temperaturas superiores as necessárias para a ocorrência do fenômeno de ponto de gota.

Jul 31, 2018

By E. Niehuis, J. Y. Kim, H. G. Cramer, S. L. Chryssoulis, K. G. Stowe, C. Bendel

TOF-SIMS was used to detect, identify from parent molecular ions and determine the relative concentrations of collectors sorbed on the surface of mineral particles in concentrate and tailings samples from three Canadian concentrators. In the Kidd Creek Zn circuit, sphalerite lost to tailings carried on average a quarter of the amount of isobutyl xanthate present on that recovered to Zn concentrate; amyl xanthate, which is not reported as added to the circuit, was also detected on floated sphalerite and pyrite. At Brunswick, sphalerite particles lost to the scavenger tailings had ten times less amyl xanthate and isobutyl xanthate than those recovered to the Zn final concentrate, while both xanthates were detected on sphalerite floated to the Cu-Pb cleaner circuit. At Matagami, significantly more isopropyl xanthate and isopropyl dithiophosphate were detected on sphalerite recovered to the final Zn concentrate than on that lost to the Zn rougher tailings

Dec 1, 1995

By William R. Wessels

This report describes a field survey and laboratory investigation into the causes of failure of resiliently clad screen decks applied to coal preparation plants. Blinding of screen deck perforations and delamination of the resilient cladding are studied and mechanisms responsible for these failure modes are hypothesized. A laboratory test program to simulate the mechanisms was begun and abandoned when it became apparent that meaningful test results would require a substantially redirected effort. No meaningful test data was obtained from the laboratory simulation.

Jan 1, 1982

By J. M. Kuchta

Bench-scale test methods were developed by the Bureau of Mines for use by the Department of Transportation in the classification of solid and liquid oxidizers. A burning rate test is recommended for evaluating the fire hazard of solid inorganic oxidizers when mixed with a red oak sawdust as the reference combustible. A spontaneous ignition test is proposed for evaluating liquid and solid inorganic oxidizers which may decompose violently or ignite spontaneously when unmixed or mixed with the wood sawdust under unconfined conditions. Test results are compared for various representative oxidizers and a classification system is proposed for use in the government transportation regulations.

Jan 1, 1972

By Timothy M. Bruner, William J. Maloney

Faced with rapid growth that strained their current water supply capabilities, the Somerset Water Service in Somerset, KY decided to construct a new intake structure on the shore of Lake Cumberland. With an existing intake structure within 200', very hard limestone geology with calcite geodes, and lake level fluctuations as high as 50 ' ,this project posed many challenges. The following paper discusses how mechanical excavation techniques were used to overcome these obstacles.

Jan 1, 2001

By C. R. Stephan

Explosion-resistant seals in underground coal mines isolate the environment within the sealed area from the active workings of the mine. The current United States Title 30 Code of Federal Regulations (CFR) requires these seals to be constructed of solid concrete blocks. The CFR also allows for alternative methods or materials to be used to create a seal if they can withstand a static horizontal pressure of 138 kpa (20 psi), provided the method of installation and the material used is approved in the ventilation plan. The purpose of this report is to identify those explosion- resistant seals that have been tested and meet or exceed all the requirements of the CFR.

Feb 24, 1997

By Saulo Brinco Diniz

A textura cristalográfica e a densidade de discordâncias têm um papel importante nas propriedades de vários metais, podendo ser modificada de acordo com os processamentos mecânicos e tratamentos térmicos realizados, além disto, também é influenciada pela estrutura cristalina e energia de falha de empilhamento (EFE). O presente trabalho buscou observar a influência da EFE na textura cristalográfica e na densidade de discordâncias de metais CFC submetidos a laminação a frio. Os materiais usados foram o latão a, cobre e uma liga de alumínio 1050, que possuem baixa, média e alta EFE, respectivamente. Pode-se observar que diferentes níveis de EFE propiciaram, para a mesma redução da espessura após a laminação a frio, distintas texturas nos materiais utilizados e diferentes densidades de discordâncias.

Aug 16, 2017

By P Mitchell, S Pushpan, G Ferres, K Bobbermien, L Hudson

"Falling commodity prices and a rising supply surplus have ushered in a period of restraint in capital project investment across the global mining and metals sector. Competition for capital project funding has seen fewer projects progress through investment gates and a stronger focus on projects that deliver gains in capital productivity and strategic outcomes.Over the course of the 2015 financial year, EY conducted a study of 108 projects in the global mining and metals sector (EY analysis; Larsson and Ericsson, 2014; SNL Financial, 2015). The projects studied were at various life cycle stages and related to the development of copper, iron ore, gold, coal, nickel and other commodities. Each individual project investment exceeded US$1 B, and the studied group represented a cumulative investment value of US$367 B.The research found that the majority of projects were delayed and/or over budget when measured against the initial estimates made during the early stages of the project life cycle. Of the surveyed projects, 69 per cent were identified as facing cost overruns with an average overrun of 62 per cent above the initial estimate and 50 per cent reported schedule delays, even after remedial acceleration initiatives.The analysis found that budget and schedule overruns could be attributed to five key causes:project management factorsstakeholder conflictsresource constraintsregulatory, and policy-related challengesunfavourable external environment.Improving project delivery performance starts with successful planning, followed by rigorous management during delivery. From global experience on large and complex capital programs, EY has observed a consistent theme of underinvestment and a lack of focus in three often-overlooked but critical areas:implementing effective governance and reporting frameworks with lead indicators that reliably flag emerging risks while they can still be mitigatedallocating adequate cost and time contingency to account for risks across the life cycleenhancing the value of contingency by aligning contingency plans with scenario plans.This paper explores the surprising findings of the study, proposes a root cause model and examines key considerations in applying these critical enabling techniques.CITATION:Hudson, L, Mitchell, P, Ferres, G, Bobbermien, K and Pushpan, S, 2016. Are your megaproject schedules and costs under – or out of – control?, in Proceedings Project Evaluation 2016, pp 75–85 (The Australasian Institute of Mining and Metallurgy: Melbourne)."

Mar 8, 2016

By S. S. Gross

A program was conducted to determine whether sufficient quantities of the flame retardant, ammonium phosphate, could be incorporated in a water-based foam solution to prevent or delay reignition (burnback) without. significant degradation of foam properties. Up to 20% of mono and diammonium phosphate was added .to d high expansion foam solution. This mixture was applied as a high expansion foam to burning wood and coal samples. The effect of this mixture on burnback was laboratory tested by placing the wood or coal sample in front of a radiant panel. It was found that diammonium phosphate levels of 20% by weight prevented reignition without degrading foam properties. A field test was then conducted using a 20%, diammonium phosphate mixture and a control with no phosphate on a wood crib fire. The experimental foam did extinguish the crib fire faster than the control as evidenced by the smoke from the crib. However neither crib reignited.

Jan 1, 1982

By D. M. Davidson, P. F. Kerr

The Permian Cutler Formation in Kane Creek, Utah bears uranium ore in fissure-type vertical veins. This fissure vein formation and its associated host rock bleaching, weak argillic alteration, and base-metal sulfide mineralization along with the development of hydrothermal minerals, a 60 m.y. isotopic Pb/U age, and well-crystallized uraninite's structural control, give evidence of ore deposition in a hydrothermal environment consistent with Laramide mineralization. Mica polymorph studies indicate first, that temperature during the hydrothermal alteration or subsequent ore deposition did not exceed 200°; hence Cutler deposits are classified telethermal; and secondly, that rock alteration and ore deposition are closely related both in time and space, as is seen in argillic alteration sequence. Ore deposition in an alkaline to slightly acid reducing environment is postulated. Ore textures and mineral associations and distributions also indicate that carbonate complexes may have been transported with the deposing ores. Bleached rock formations are not primary strati-graphic phenomena. Bleaching, or changes in ferric iron content, results from a chemical process involving reduction and conversion of hematite to a soluble aqueous ion. Nearby Chinle bedded deposits (Moss Rack sandstone), containing shale lenses, fossil wood, organic debris and minor fractures, overly the Cutler formation. Chinle ores have a single reported isotopic age of approximately 200 m.y. Their chemical environment is assumed similar to that of the Cutler ores, though slightly more acidic. Two genetic, paradoxically divergent interpretations of the bedded deposits are derived from available spectrographic, petrographic, X-ray and chemical analyses. Kane Springs canyon is located southwest of Moab, Utah, south of the Colorado River and northwest of the Lisbon Valley mining district (Fig. 1). Uranium deposits occur along the northeast flank of a Kane Creek salt anticline where two geologic formations bear ore, the Permian Cutler and the Triassic Chinle. The Cutler deposits' fissure vein formation is an unusual occurrence in the Colorado Plateau. The Chinle deposits appear to be of the normal sedimentary type. Associated with the vein deposits are a number of features, including argillic alteration of sedimentary strata. The minerals of these deposits and their associated features have been studied in detail in a two year program entailing both field and laboratory techniques. STRATIGRAPHY A stratigraphic section of the lithologic units in the Kane Creek area is given in Table I.

Jan 1, 1967

By Sohta Takatsu, Hachiroh Mizubata, Shigeki Kudoh, Kazuya Takekuni, Yoshinori Yamada

A special type of shotcrete is used to improve the performance of open-type TBM in difficult situations. The Hakamagoshi and Johana tunnels are expressway evacuation tunnels of 3.2 km and 5.1 km in length, respectively (total 9.1 km) that were excavated by one open-type TBM. The geological conditions at the sites were estimated to be good before excavation. However, 95% of the rock turned out to be two ranking orders worse than the estimated classes. Therefore, we used a special shotcrete for bad rock conditions, and succeeded in excavating the tunnel at an average rate of 270 m/month.

Jan 1, 2001

By Joseph D. Davis

Selection of a suitable coal or coals for the manufacture of coke of desired quality with due consideration of the purpose for which the coke is intended requires careful thought, and often it will pay to go to considerable expense in testing such coals as may be available. In general it will

Jan 1, 1942

By F. Habashi

The Republic of South Africa is a heterogeneous mixture of Black Africans, Afrikaans, British, Indians, Malayans, French Huguenots, and many others from Europe and Asia. A decisive date in its recent history is the collapse of the Apartheid Regime in 1994. For a metallurgist, South Africa is the country of diamonds, gold, platinum, and many other metals. In 1887 Cecil Rhodes (1853-1902) was able to take control of the De Beers Mining Company after the discovery of diamonds at Kimberly in 1866. It was there where the so-called School of Mines was inaugurated in 1896.

Jan 1, 2010

By C Swamydas

VV Mineral (VVM) group of companies is the largest and the first private producer and exporter of beach sand mineral products in India. During 2010, the company produced and marketed around 750 000 tons of saleable products. Their operations are mainly in the state of Tamil Nadu and Andhra Pradesh, India. Almost all the wet pre-concentration plants use sea water as the concentration medium, since there is no fresh water source available near the deposits. The mines are located along the south-east coast of India in the states of Tamilnadu and Andhra Pradesh. The orebody varies in terms of mineral assemblage, slime content, grain size, and surface coating resulting in different behaviour of the minerals. Three different deposits containing ilmenite of different TiO2 content were studied. The study shows that there is no significant impact of using sea water for wet concentration prior to high tension separation of ilmenite. There is no significant variation in recovery and purity of ilmenite produced from these deposits when wet concentration of the deposits were carried out with sea water as the concentration medium and whether the concentrates were washed with fresh water or not before dry separation using High Tension Roll Separators (HTRS).

Oct 5, 2011

The Annual General Meeting of the Institute was held in Kelvin House, Johannesburg, on Wednesday, 27th August, 1969, at 4.15 p.m. Mr. R. C. J. Goode (President) was in the Chair. There were also present seventy Members, ten As¬sociate Members, two Affiliates, one Student and twelve Visitors making a total of ninety-five. The President declared the meeting open at 4.20 p.m. OBITUARIES The President: "It is my very sad duty to announce the deaths of the following members of the Institute: Mr James Charles Napoleon Humphreys, a Life Member who joined the Institute on 1st April, 1935, and passed away on 6th February, 1969. Mr Michael John Worrall, Graduate Member, who joined the Institute in 1960 and passed away on 2nd June, 1969. Mr Eric Adam Conrad Dickson, Associate Member, who joined the Institute on 13th June, 1952 and who passed away on 8th June, 1969. Mr Robert Jack, Associate Member, who joined the Institute on 2nd August, 1956, and passed away on 14th June, 1969. Mr R. A. H. Flugge-de-Smidt, Honorary Life Member and Gold Medallist, who joined the Institute in 1922 and passed away on 17th June, 1969. Mr John Gordon Craig, a Member who joined the Institute on 23rd August, 1960, and passed away on 6th August, 1969. As a mark of respect to the memory of the deceased, and in sympathy with the bereaved, I would ask you to rise and observe a few moments silence." MINUTES The President: "May we confirm the Minutes of the General Meeting held on 18th June, 1969, as published in the July, 1969, issue of the Journal?"-Agreed. WELCOME TO VISITORS The President: "We are honoured this afternoon by the presence of the Institute's Honorary President, Mr R. S. Cooke, President of the Chamber of Mines of South Africa, and by one of our Honorary Vice-Presidents, Mr T. L. Gibbs, the Government Mining Engineer, as well as by the presence of many distinguished guests, to all of whom I extend a most cordial welcome. We are happy to have present, Mr S. C. M. Naude, Director of the Witwatersrand Technical College, Mr G. A. P. Louw, Vice-President of the Associated Scientific and Technical Societies, Mr R. P. Randall, Senior Vice-President of the South African Institute of Electrical Engineers, Mr W. T. L. Wayman, President of the South African Institution of Mechanical Engineers, Mr D. F. Odendaal, President of the Institution of Certificated Mechanical and Electrical Engineers of South Africa, Mr E. Haacke, President of the Institute of Land Surveyors of the Transvaal, Mr B. L. Loffell, Vice-President of the South African Institution of Civil Engineers, Mr J. F. Leatherbarrow, President of the South African Institute of Assayers and Analysts, Dr W. S. Rapson, President of the Joint Council of the South African Scientific Societies, Dr P. L. Carman, President of the South African Chemical Institute, Mr F. Jackson, President of the Federation of Societies of Professional Engineers, Mr W. E. Kirkwood, President, S.E.I.F.S.A., Mr J. Steele, President of the South African Institute of Foundrymen, Mr M. Waite, President of the South African Institution of Welding, Mr M. R. Gericke, President of the South African Council of Professional Engineers, Mr G. C. Sowry, Chairman, Witbank-Middelburg Branch, Mr T. Groenewald, Chairman of the South African Chemical Institute (Southern Transvaal Section), Professor O. B. Volckman, Chairman of the South African Institution of Chemical Engineers, Mr H. W. Le Roux, Chairman of the South African Federation of University Engineer¬ing Students, Dr R. E. Robinson, Director of the National Institute for Metallurgy, Mr P. H. Anderson, Deputy-Chairman of Rand Mines Limited, Mr E. Boden, Manager of the A.S. and T.S. and Count Folchi-Vici, from Italy, who has lime interests in this country. I also extend a very special welcome to the lady guests here this afternoon, and to all the visitors." MEMBERSHIP The President: "I have pleasure in announcing that the names of the following candidates, having been published in accordance with By-Law 5.2.2, Council has elected them to membership in the following grades: NEW APPLICATIONS Members: Stuart Denston Hill, Robert Roy Richardson, Gert Paulus van der Vyver. Affiliates: Henry Clifford Read, Allen Edward Hooper, Alan Edwin Edkins. Graduates: Lester Winston Sturgess, Erroll Vincent Bosman. Students: Terence Vernon van Heerden, David Curtis Lindley. MEMBERS TRANSFERRED TO A HIGHER GRADE From Associate Member to Member: Andries Willem van Zyl, Roy Lardner, Nugent Gerald Ward Comyn. From Student to Graduate: Michael John Worrell (now passed away), Peter John Hamilton Short. I wish to welcome the new members to the Institute, and to congratulate those members who have been transferred to a higher grade." ANNUAL REPORT OF THE COUNCIL AND ACCOUNTS FOR THE YEAR ENDED 30th JUNE, 1969 The President: "Ladies and gentlemen, It is with much pleasure that I present to you the Annual Report and Accounts for the year ended 30th June, 1969. These have been laid on the chairs and before calling for their adoption I would like to make a few comments. The Accounts show an excess of expenditure over income of R2,124 and our Honorary Treasurer, Mr D. G. Maxwell, will in due course comment on this. The main difficulty has again been the cost of the Journal and I think most of you are aware of the changes that we propose to make. I shall be sorry to see the last of our old format but then I have always had rather a con¬servative outlook.

By Richard C. Rice

Laboratory and field data for wire ropes typical of constructions used in underground mine hoisting were obtained, screened, encoded and analyzed statistically. The statistical analysis of data for hoist ropes retired from service showed that rope remaining strength (or, conversely, strength loss) can be predicted with good accuracy if several nondestructive measures of rope damage are assessed. Found to be most important was the outer-wire corrosion rating, the electromagnetic (EM) nondestructive-inspection technique used for predicting strength loss, and the rope diameter reduction. Signs of rope deterioration such as broken wires or damage were also important indicators of strength loss. Based on the results of this investigation, a number of recommendations are presented that promise to yield better rope inspection and retirement criteria which will in turn lead to improved safety and efficiency in underground mine-hoist systems.

Jan 1, 1983

By S. Serranti

A fast, reliable, and low cost characterization of ore minerals products, as they result from different processing actions, represents one of the most challenging targets in the mineral processing sector. Today different techniques are available according to different sampling strategies and analytical principles. In this paper, the possibilities offered by the adoption of hyperspectral imaging based sensing units working both at micro- and macro-scale are presented and discussed. According to the different phases and stages of ore minerals and products characterization, and starting from the analyses of the detected hyperspectral firms, it is thus possible to derive useful information about mineral flow stream properties and their physical-chemical attributes. This last aspect can be utilized to define innovative process mineralogy strategies and to implement on-line procedures at processing level. The present study discusses the effects related to the adoption of different hardware configurations, the utilization of different logics to perform the analysis and the selection of different algorithms according to the different characterization, inspection, and quality control actions to apply. Keywords: process mineralogy, hyperspectral imaging, NIR spectroscopy, surface mapping, textural analysis, quality control

Sep 1, 2012

By B. R. Utz

The goal of the DOE Coal Preparation Program is to provide industry with the scientific and engineering knowledge base to produce economically competitive and environmentally acceptable clean coal products for both existing and new markets. The DOE/PETC in-house program continues to conduct fundamental, exploratory, and applied research in the areas of physical, chemical, and microbial coal beneficiation to assist in meeting these goals and objectives. The Coal Preparation Division now has a new Coal Preparation Process Research Facility that allows continuous bench-scale testing of emerging coal cleaning technologies and ancillary coal preparation equipment at feed rates up to 1,250 kilograms (1.25 tons) per hour. Bench-scale and laboratory-scale research projects at PETC cover areas such as 1) the use of micronized-magnetite for fine-coal, 2) heavy-media cycloning, 3) fine coal reconstitution, 4) development and testing of coal preparation process flowsheet simulators, 5) dry coal beneficiation using electrostatic methods, 6) tracer methods to determine the efficiency of density-based separations, 7) selective oxidation of organic sulfur, and 8) microbial removal of pyrite and organic sulfur from coal. This paper will discuss several of these research areas.

Jan 1, 1993