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By P. D. Lindahl

[A cost/benefit analysis was conducted by comparing the industry cost to protective structures on low-coal face equipment with the benefits paid for injuries/fatalities considered preventable by the use of these structures. Th industry costs were based on estimates by OEM's and rebuild shops for install protective structures on new and rebuilt face equipment. The accident benefit was based on evaluations performed by the USBM Accident Cost Indicator Model. Industry wide population data were developed on low-coal face equipment and injuries/ fatalities preventable with protective structures. The results of the analysis are to be used as a tool by USBM in determining the feasibility of continuing development of cab and canopy technology for low-coal equipment.]

Jan 1, 1983

By Alvin Kaufman

Increased exploration in Alaska has resulted in many requests to the Bureau of Mines for facts about the mineral resources and mining conditions in the Territory. This report presents information about the minerals of Southeastern Alaska and the factors that affect development of a mining industry in that area. Southeastern Alaska is a narrow coastal strip of rugged mountains and many islands. The climate is mild, with an average annual temperature of 40° and heavy rainfall. Geologically, the region is favorable for deposition of ore; geographic-ally, it is difficult to prospect and to develop, except along areas immediately adjacent to the coastline.

Jan 1, 1958

By Leslie H. Sharp, Martin J. Gavin

"Introduction.Investigations of the oil shales of the State of Colorado were begun February 1, 1920, by the U. S. Bureau of Mines and the State of Colorado, under cooperative agreement entered into by the Bureau and the State, funds for which were provided by the State. The investigations are for the purpose of determining by large-scale Laboratory retorting tests, those conditions which will produce optimum yield of best quality products from Colorado shales. (For an outline of the work and description of the apparatus, see Gavin, Martin J., and Sharp, Leslie H., ""investigations of the Fundamentals of Oil-shale Retorting,"" Reports of Investigations, Bureau of Mines, July, 1920.)In the preliminary work which is usually required when a new material is being dealt with, certain physical and chemical constants of the shales being investigated, and their products, were determined; these data will be of much value not only to the thorough retorting tests now under way at Boulder, but to engineers who will design and construct oil-shale plants. While the figures presented in this report apply only to the shale used in the determinations, strictly speaking, the shale used was selected to represent, as well as possible, an average of the massive type of oil shale encountered in Colorado. The figures, therefore, can probably be applied with little danger of serious error to any massive Colorado oil shale which yields in the neighborhood of a barrel (42 gallons) of oil to the ton.This paper is based on a more complete article now being prepared in which experimental methods are explained in full, and complete experimental data. For the purpose of presenting the data with as delay as possible, it has been decided to anticipate the more complete article with the present report."

Aug 1, 1920

By Hamid-Reza Manouchehri

"The triboelectric charge attributes of feldspar, quartz and wollastonite minerals, after contacting different triboecharging medium made of different materials, were considered. Their charge acquisitions by different size fractions of minerals were monitored and accordingly their energetic work function values were estimated. Moreover the separation behaviours of these minerals through the electric field of a laboratory free falling separator were determined and the effects of some chemical reagents on separation their separation characteristics were studied.Finally an attempt was made to translate the findings from single mineral systems to a complex silicate ore, containing quartz, feldspars, wollastonite and some other silicates. The results show favourable prospect to apply the triboelectric separation technique for beneficiation such a complex raw material."

Jan 1, 2003

A Special General Meeting, followed by the February General Meeting of the Institute, was held in Kelvin House, Johannesburg, on 18th February, 1970, at 4.30 p.m. Mr J. K. E. Douglas (President) was in the Chair. There were also present 24 Members: Messrs A. R. C. Fowler, R. C. J. Goode, Prof D. D. Howat, Messrs D. G. Maxwell, J. A. Nixon, P. W. J. van Rensburg (Council Members), C. A. Border, J. C. Fritz, E. K. Gibson, P. L. Grimbeek, S. D. Hill, D. A. Immelman, P. J. Uoyd, M. Mrost, C. S. Macphail, D. G. Malan, W. D. Ortlepp, R. S. Pearson, A. J. H. Pole, Dr W. S. Rapson, L. W. P. van den Bosch, R. A. von Maltitz and Dr A. Whillier. Eight Associate Members: Dr M. I. Brittan, Messrs J. Brett, I. E. Clarke, C. L. de Jongh, W. B. Evans, D. Loubser, R. C. More O'Ferrall and G. R. Still. One Graduate: Mr T. J. Kotze. One Student: Mr J. A. Cruise. Nine Visitors: including Dr N. G. W. Cook, Messrs M. D. Labuschagne, A. Nicoll, S. Sadowski, Dr A. M. Starfield and Dr H. Wagner. Secretary: Mr D. C. Visser. Total present: 45. SPECIAL GENERAL MEETING The President: "You will have received notices of the Special General Meeting and I declare it duly constituted. In keeping with the trend of overseas and local institutes, your Council recommends that we should change our membership classification as indicated in the notes of the meeting. The new grades are proposed to replace those presently in the Constitution and By-Laws. In terms of Clause 4.8 of the Constitution a special general meeting must be held for the purpose of considering and, if approved, adopting with or without amendments, the revision of the undermentioned clauses of the Constitution, which Council now recommends should read as follows. Clause 2.2 'Corporate Members shall comprise the grades of Honorary Life Fellow, Fellow and Member', these being the equivalent of Honorary Life Member, Member and Associate Member. Clause 2.6. 'Non-Corporate Member shall comprise the grade of Honorary Fellow, Graduate, Associate and Student.' Are there any questions in regard to this proposal? If not would someone propose that these clauses be amended and adopted?" Proposer: Mr A. J. Nixon. Seconder: Prof D. D. Howat. The motion was then adopted. The President: "It is recommended that Clause 2.15 should read, 'A Corporate of the Member of the Institute shall be entitled to use the following authorised letters designating the grade of Membership in Honorary Life Fellow and Fellow, F.S.A.I.M.M. and Member, M.S.A.I.M.M.' Previously we used the letters M.S.A.Inst.M.M. and your Council considered that we should adopt the simpler lettering. Could I ask someone to propose that this amendment be adopted?" Proposer: Mr R. C. J. Goode.

By Max Hebgen

Within the State of Montana the streams rise in the high mountains at. an elevation of from 5,000 to 8,000 ft. These streams leave the State line both east and west at elevations from 3,500 to 2,400 ft. It is, therefore, apparent. that all these streams have an average fall of 3,000 ft. within the confines of the. State, and many opportunities are presented on all streams. for the development of power, by taking advantage of the natural fall. It is probable that 1,000,000 h. p. can :be developed in the State of Montana. I. NATURAL FEATURES OF STATE AFFECTING POWER DEVELOPMENT. The main. range of the Rocky mountains, forming the Continental Divide, cuts the State of Montana into two parts. The eastern part is drained by the Missouri river and its tributaries, the Madison; Jefferson, Gallatin and Yellowstone, rivers. The western part is drained by tributaries to the Columbia river, the Clarks fork and the Kootenai river. The Clarks fork in turn is formed by the junction of Missoula and Flathead rivers, the latter, draining Flathead lake. The western part of the State. is mountainous and the eastern part is comparatively level. As a natural result the rivers in the western part are capable of generating large amounts of power, while in the eastern part of the State natural power sites are much fewer and farther apart. It also follows that in the mountainous districts large amounts of power are required for the mining industry, while in the eastern part of the State, which is principally devoted to agriculture, power is required in smaller quantities. ?

Jan 8, 1913

Watershed Jll in Jefferson County, Ohio we instrumented in 1977 as one of three watersheds established for the purpose of investigating surface mining and reclamation effects upon local hydrology, sediment discharge, and sediment and water quality. Each watershed was less than 50-acres in size, and was in a different geologic setting within southeastern Ohio. Surface runoff and ground¬water levels were monitored. Samples were taken for sediment determination and chemical analysis prior to mining. Monitoring and sampling continued through the period of watershed disturbance caused by mining and reclamation activities, which began in May 1980 at Watershed Jll. A psuedo-postreclamation period followed the initial cessation of man-machine activity on the watershed. A second reclamation effort occurred in the fall of 1981 and was to be followed by a third in 1982 after observations ceased. A true final postreclamation period was not monitored at this site, because the erosion control practice (terrace diversions) failed after each reclamation. Watershed Jll was a small pasture and wooded watershed with sandstone and shale above the mined coal seam prior to mining. A clay layer under the coal supported a perched saturated zone, termed the top aquifer for convenience. A lower underclay supported a second saturated zone called the middle aquifer. A lower perched aquifer had been dewatered by previous deep mining. After about three years of premine data and about two and one-half years of mining reclamation and psuedo-postreclamation data, the following general observations may be made: 1. The mining-reclamation phase was very short, and the postmining period was characterized by erosion failures and remedial disturbances that kept the watershed condition and size in a state of change. It was impossible to collect sufficient data to confidently characterize the hydrologic-sediment-chemical aspects of the mining period or of a postreclamation period and, most importantly, of the future watershed after its various properties and characteristics have ceased adjusting to its severe disturbance and reconstitution. 2. A seeding of wheat followed by grasses and legumes was not a particularly successful reclamation practice in terms of stabilizing the new soil. Numerous rills and small gullies developed in spite of installed diversions. 3. Storm runoff rates and yields at the watershed outlet increased from the premine, (phase 1) to the mining-reclamation (Phase 2) periods, and remained at or near the Phase 2 level through the postreclamation (Phase 3a) period. 4. The top aquifer changed in physical and chemical character as a result of mining and was becoming reestablished as the project drew to a close; but it is impossible to predict its final configuration or character. 5. Dewatering of the top aquifer resulted in a complete cessation of baseflow because the middle aquifer water table lay below the elevation of the watershed outlet. 6. The top and middle aquifers were merged in one area of the watershed where the upper coal underclay was disturbed. 7. Failure of the diversion terraces and their outlet obscured the effects of the reclamation practice upon sediment concentration and yields. There was little difference in sediment concentrations between Phases 2 and 3a. 8. Drinking water standards were met by surface waters throughout the period of observation except for two samples that exceeded the nitrate-N allowable level of 10 mg/l. 9. In all Phase 3 surface-water samples, iron concentrations were within the limits established by OSM, and manganese concentrations exceeded the regulation level only once. pH fell below the lower regulation level of 6.0 between 10% and 20% of the time. 10. The chemical quality of sediments was generally about the same after reclamation as before mining, with the exception of organic carbon, which decreased.

Jan 1, 1983

By C B. McCampbell, R W. Jr Bickes

Sandia National Laboratories has developed a semiconductor bridge (SCB) igniter for the ignition of a variety of explosive materials. When subjected to a low-energy current pulse, the bridge bursts into a plasma causing rapid ignition of the explosive material pressed against the bridge. Despite the low energies required for ignition, SCB components have proven to be explosively safe, meeting both no-fire and electrostatic discharge (ESD) safety requirements.

Jan 1, 1991

By Jilai Xue

Fe-Ni alloys can be used as raw material in making stainless steel. Laterite nickel ore is one of mineral resources for producing nickel alloys. In this work, the laterite ore after dehydration at 800 °C and the anthracite as reducing agent were mixed for pre-reduction at 900 °C, and then reduced to form Fe-Ni alloys at 1550-1620 °C through carbon-thermal reduction process. A high Ni-content alloy component in the metallurgical mixture can be formed through pre-reduction. Better separation of the resulting metals from the slag is found with lower Ni-content alloys produced or higher temperatures during reduction. An effective processing of Fe-Ni alloys needs further understanding of the process fundamentals and optimizing of the process parameters.

Jan 1, 2010

By P. Kawulka

An integrated pilot plant for the development of the S-C Copper Process was constructed at Fort Saskatchewan in 1975 and operated in 1976. The pilot plant was designed to treat 9 tonnes per day of a pyritic copper concentrate. A demonstration run conducted during the last quarter of 1976 averaged 90% on-stream time, and confirmed that the process is operable as a stable and integrated unit. The paper describes the parameters and equipment developed for thermal activation of chalcopyrite copper concentrates to make them amenable for the dissolution of iron and zinc, and their subsequent separation and recovery. The resulting high-grade copper sulphide was leached with return electrolyte and oxygen to extract 98.5% of the copper into solution. The copper was electrowon at 650 amps per square metre from purified solution, to produce cathodes analyzing 0.1 ppm Se, 0.1 ppm Bi, 4 ppm Pb and 10 ppm S. The electrical conductivity was >101% lACS and the spring elongation value [ ]350 mm. Elemental sulphur and gangue are removed from leach residues to make a concentrate containing over 95% of the silver and gold and most of the unleached copper. Conventional construction materials such as stainless steel, titanium, Hastelloy, acid brick, rubber and plastics performed well. The containment inherent in hydrometallurgy provided high standards of hygiene and safety.

Jan 1, 1978

By S. L. GILLAN

OF the forty or more excursions provided for the delegates to the World Engineering Congress at Tokyo, the trip to the Ashio copper mine stands out as one of the most enjoyable. In every detail looking to our comfort and pleasure the Furukawa company, our hosts, were admirable. This company operates five other copper mines, also gold and coal mines. Ashio is the largest with an annual production of about 14,000 tons of copper. It has been continuously worked since 1620, and doubtless was one of the sources of copper used in the gigantic statues of Buddha of many hundred years earlier date.

Jan 1, 1930

By Alla D. Mah

Titanium forms several compounds with oxygen and also is able to dissolve interstitially about 33 atomic percent of oxygen. Starting with titanium dioxide, reduction becomes increasingly difficult as oxygen is removed; and the final step, be reduction of the titanium-oxygen interstitial solutions, is by far the most difficult. The possibility of reducing titanium oxide, or of purifying titanium containing oxygen, by treatment with certain more volatile metals has been a subject of considerable interest. Theoretical appraisal of the limitations of this possibility, however, has been hampered by lack of adequate information on the thermodynamic properties of the titanium-oxygen solutions. The purpose of the present work was to remedy this difficulty by expanding the thermodynamic knowledge regarding these solutions. The experimental work involved three types of calorimetry and furnished the following information: (1) Heats of formation of 11 titanium-oxygen solutions, in the range of 0 to 10 wt.-percent oxygen, were determined at 298.15° K. As a byproduct, an improved value of the heat of formation of rutile was obtained, which, in turn, led to improved values of the heats of formation of the lower titanium-oxygen compounds. (2) Low-temperature heat-capacity data and entropies at 298.15°K in were determined for 2 representative titanium-oxygen interstitial solutions. (3) High-temperature heat-content data were obtained for 2 titanium-oxygen interstitial solutions to about 1,600° K.

Jan 1, 1957

By A. K. Anyimadu

Ongoing development work on ultra-fine grinding for various applications at the Group?s concentrators has been conducted by Anglo Platinum over the last few years. Current potential applications for mainstream grinding and concentrate grinding are the subject of a group-wide research and development programme. The first 10 000-litre 2.6 MW IsaMill was jointly developed by Anglo Platinum, Xstrata Technology and Netszch for installation at the Western Limb Tailings Re-treatment project in Rustenburg, South Africa. The unit was commissioned in late 2003/early 2004,and has operated in an intermediate concentrate regrind application successfully since. This paper describes the operational performance to date, as compared with the original duty specifications and objectives. The first mainstream M10 000 IsaMill with a 3 MW drive will be operational in November 2006 at the Potgietersrus Platinum (PPL) ?Platreef? Sandsloot Concentrator in South Africa?s Limpopo Province. Keywords: Western Limb Tailings Re-treatment Plant, IsaMilling, Platreef, platinum, palladium, PGMs, tailings.

Jan 1, 2007

By Stuart F. McTavish

Mechanically suitable grinding mills became available to the mining industry in 1908. Since then, mill operators have been searching for the best material and design with which to line the mills. These liner systems had to fulfill several criteria. Most important, they had to last long enough in an operating mill to protect its structure from the abrasive wear of the ore and the grinding media. In addition, they had to be capable of efficiently transferring the energy from the mill to the mill charge in order to facilitate the grinding process. And these liners had to be easy to install and remove. The first liners used were generally made of cast white iron, Hadfield manganese, unalloyed high-carbon steel and composites of steel and concrete or cemented in flint blocks or natural stone. In the early 1920s, pieces of solid rubber truck tires were used as emergency repairs for broken cast metal liners. Thus was rubber first introduced as a mill liner material. The first patent for rubber mill liners was awarded in 1921 to James Denny and Rolla Watson, both of the Coniagas Mine in Cobalt, Ontario, and to Dale Barnum of the Comstock Lode in Virginia City, NV. This original design was covered under US Patent No. 1470597. It had a fabric backed rubber that was bonded to the shell of the mill.

Jan 1, 1990

By B. W. Gandrud

To say that the treatment and handling of the "fines" is the most difficult phase of coal preparation is probably an understatement of facts. It is the fine sizes from about 1/16-inch to 0 that are mainly responsible for the inescapable sludge and slurry problems at plants using wet methods of preparation. Sludge and slurry are a problem from the standpoints of both cleaning and dewatering. They cannot be cleaned satisfactorily by "gravity" methods, which are used so extensively on coarser Sizes, due to the fact that fine sizes, particularly from 65-mesh to 0, do not follow the same laws of settling as do the coarser sizes. Although fine sizes are cleaned more successfully on wet-wash tables than in jigs, even tables as usually operated in coal-preparation plants fail on sizes below 100-mesh. As to other phases of the, sludge and slurry problem, wet coal preparation plants are almost universally beset with troubles in connection with the recovery and dewatering of the fine sizes from about 14-or 20-mesh to 0. The sizes finer than 100-mesh further complicate the problems in a wet preparation plant by their tendency to stay in suspension and build up a troublesome load of solids in the circulating water. In order to prevent too much trouble from this source, it is, customary at most plants to bleed a fair-sized stream out of the circulating system continuously and replace it by addition of fresh make-up water. The slurry water withdrawn from the circuit is usually run to waste, in which case it carries with it a considerable amount of fine coal, thus increasing the "washer loss." Another evil results from wasted slurry water in that quite often it finds its way into creeks and larger streams, creating stream-pollution problems.

Jan 1, 1948

By Sam Kangwa, Thomson Sinkala

Th e re are three basic types of hole deviations in long hole d ri l l i n g , n a m e l y collar i n g , alignment and tr a j e c t o r y dev i a t i o n s . In mining, the accur a cy in drilling has a significant effect on the effi c a c y and economy of mining oper a t i o n s . This ar t i cl e d e s c ribes the types, s o u r ces and effects of hole deviations in mining oper a t i o n s . The art i cle further demonstrates the economic consequences due to hole dev i a t i o n s .

Jan 1, 2004

By Mônica Aline Magalhães Gurgel

A crescente preocupação da indústria automobilística com questões ambientais e com a segurança do condutor e passageiros, fez com que o setor siderúrgico desenvolvesse aços com maior valor tecnológico, entre eles surgiu os aços avançados de alta resistência, onde encontra-se o “Dual Phase” (DP) utilizado nesse estudo, que é caracterizado por uma microestrutura associada a uma matriz ferrítica com ilhas dispersas de martensita. Neste trabalho utilizou-se amostras de um aço baixo C e Mn, com micro adição de Nb e Mo, em desenvolvimento, onde se propôs uma avaliação das propriedades mecânicas através de um Ultramicrodurômetro, as amostras extraídas após a laminação a frio seguiram para o recozimento intercrítico, em escala laboratorial, com auxílio de forno Mufla e um equipamento de análise termomecânica (TMA), com 7 temperaturas de encharque distintas e subsequente resfriamento com patamar isotérmico a 600°C por 20 minutos. Onde observou-se que a utilização do ultramicrodurômetro instrumentado mostrou ser uma ferramenta com grande potencial para a avaliação almejada.

Aug 17, 2017

The Mineral Sector Development Project, sponsored by the World Bank, has been set up to revise the legal, regulatory and fiscal framework for the minerals industry in Tanzania, with a view to attracting mining companies and investors to the country and facilitating future minerals development. One component of this project, the Environmental Management Framework for the Mineral Sector, was awarded to Wardell Armstrong of the UK and ENV Consult of Tanzania. In developing a new framework of environmental regulations, emphasis was placed on developing realistic standards which reflect local conditions and prevailing values. The main corner-stones of this approach are; effective environmental impact assessment procedures; establishment of environmental management procedures; and monitoring and auditing of companies? performance. The favoured approach involves a three-tier framework, as follows: ?Framework environmental provisions within the new Mining Act; ?Regulations covering more detailed environmental requirements ?Guidelines and/or Codes of Practice, which may in future become regulations in their own right. Careful consideration has been given, in developing the framework, to the limited resources likely to be available for implementation to the Ministry of Energy and Minerals and this has influenced the approach that has been adopted. This paper outlines the main components of the environmental management framework and discusses some of the important issues raised by these proposals.

Jan 1, 1998

By P. Wells

"In the past decade, there have been many developments in processing of nickel/copper sulfide ores. Improved pentlandite/pyrrhotite flotation selectivity with the use of new reagents, fine regrinding and Redox measurement (control) has led to increased pyrrhotite rejection and thus higher concentrate grades. Flash flotation has increased overall nickel and associated precious group metal recoveries. Recovery of both fine and coarse particles has been improved through an understanding of flotation cell hydrodynamics. The separation of copper from nickel in such ores has seen a similar level of development. From the late 80s to very recently, the use of flotation columns, the use of pyrrhotite depressing reagents and the improved understanding of the complex mineralogy of chalcopyrite, pentlandite and pyrrhotite have considerably increased copper / nickel separation efficiency. Copper concentrate with more than 30% copper and less than 0.5% nickel grade is now obtainable at 80-85% copper recovery from mill feed compared to 70-75% copper recovery with 30% copper and 1% nickel grade only a few years ago. Improved copper / nickel separation in milling operations has the potential to substantially improve the processing of the resulting concentrates and thus the overall return from the extraction of nickel and copper from sulfide ores.INTRODUCTIONNickel metal by itself or in alloys with other metals and materials makes a significant contribution to modern society. The relatively high price that nickel commands compared to other base metals is a reflection of the fact that, although abundant in the universe, nickel is sparingly distributed in the earth’s crust. There are two types of nickel deposits that are currently being exploited: complex sulfide ores and lateritic oxide ores. Lateritic contain no copper but in sulfide deposits, nickel– bearing minerals, principally pentlandite (Pn, [Ni,Fe]8S9), some millerite (NiS) and violarite ([Ni,Fe]S) are often found in association with copper-bearing minerals, mainly chalcopyrite (Cp, CuFeS2) and cubanite (CuFe2S3). The copper content of such ores can vary considerably from as high as 5-8% (in some Sudbury basin ores) to as low as 0.1% (in ores mined by Western Mining at Mount Keith, Western Australia and by Inco in Thompson, Manitoba). The valuable minerals Pn and Cp are almost invariably found associated with pyrrhotite (Po, Fe7S8) which along with nonsulphide rock has to be rejected to tails in the primary milling stage. The bulk concentrate from the primary stage is then treated to depress Pn and float Cp. A complete Cu/Ni separation at the mill would be highly desirable but this is not possible because of locking between a small fraction of the valuable minerals. As a result, Cu/Ni separation has to be carried out both during milling and during refining of the matte following smelting. At Inco, Jinchuan and in Norilsk, a chalcocite / heazlewoodite separation is made by flotation following slow cooling of the matte. In the present Sudbury Inco operations, Cu/Ni separation has not been conducted at the mill since 1991 and all Cu/Ni separation takes place at the matte processing plant. Because of the rising ratio of Cu to Ni in the ore, this strategy is under review and this paper describes some recent studies of circuits in preparation for possible installation of a copper / nickel separation circuit at Inco’s Clarabelle Mill in the Sudbury area."

Jan 1, 2004

By Marcos Meyer Machado

O presente trabalho compreende um estudo sobre os processos de moagem e tratamento térmico de pelotas no que tange as implicações microestruturais de minério de ferro no controle operacional e redução de consumos de energias térmica e elétrica de uma planta de pelotização. As características físicas, microestruturais e mineralógicas foram determinadas para os produtos de minério de ferro, para matriz de experimentos (misturas) e para as pelotas tratadas com auxílio de um microscópio óptico, um eletrônico e um EBSD. Os resultados permitiram confirmar a relação entre as composições morfológicas com a elevação de produção da moagem (14,1%) e redução do consumo de energia elétrica (12,0%). O controle do perfil térmico de endurecimento foi relacionado com as condições de sinterização (grau de maturação) das pelotas submetidas e as fases microestruturais identificadas. Foi evidenciada relação inversa entre o teor de magnetita na mistura com o consumo de energia térmica. Os resultados de resistência à compressão também sugerem uma relação inversa com os teores de fayalita e magnetita não oxidada, porosidade e grau de maturação. Adicionalmente, os resultados proporcionaram ajustes industriais que confirmaram essa relação com a redução da energia térmica aplicada para produção (10,7%).

Oct 30, 2017