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By Nichols. R. S.

"Surface coal mining production from Elk Valley and area in southeastern British Columbia began in 1913. Since 1970, five open-pit mines have been put into production: Westar Mining&apos;s Hanner and Greenhills Operations; Fording Coal&apos;s Fording River Operation; Byron Creek Collieries&apos; Coal Mountain Mine and Crows Nest Resources&apos; Line Creek Operation.ln 1983 these mines produced 14.9 million tonnes of raw coal at an average strip ratio of 4.9 bank cubic metres of waste to 1.0 tonne of raw coal. This is 70% of the estimated 21.1 M tonnes annual capacity .Multiple seams are recovered with truck/shovel and dragline equipment. There is a wide range of equipment types in use with a recent trend toward larger and more mobile equipment.Coal mining in Elk Valley involves advancing along strike in four steps: hangingwall waste removal; seam cleaning; coal recovery; and foot wall waste removal. Each mine is unique in its approach to these four steps but the truck/shovel methods can be categorized into three main groups: seam dips < 35 degrees as at Harmer, Fording and Greenhills; seam dips 35 to 50 degrees as at Line Creek; and seam dips >50 degrees as at Byron Creek. Dragline mining at Fording involves bath waste and coal removal by draglines."

Jan 1, 1984

By Xiaojing Li, Yueyuan Zhou, Shengyao Ma

The paper presented the acnalysis of field intensity of rare-earth permanent magnet with high BH product and the research of magnet configuration with narrow pole pitch on open magnet surface, both using ANSYS. The possibility to separate micro-disseminated feebly magnetic minerals by improving the field intensity and the capture line distribution rate on open magnet surface were verified. The research on the method to pile up magnets to increase peak value of field intensity on the open magnet to 1.0T was done through correlation analysis between shape and dimensions of magnetic material and field intensity. And the research on technology method to improve capture line distribution rate in the separating field to 1.25×105/m2 was done through optimization design of magnet configuration of the open magnet with narrow pole pitch. Laboratory tests were performed with hematite sample from ore dressing plant such as Hainan mine, Qidong iron ore, etc. The separation results acquired were at the same level as using the electromagnetic separator, verifying the possibility to separate micro-disseminated feebly magnetic minerals with open magnet. The research suggested a new idea about the development of magnetic separator with high efficiency and low costs to separate feebly magnetic minerals and non-magnetic gangues.

Jan 1, 2014

By John Hall

(New York Meeting, October, 1913.) THE Fremont test for measuring the energy consumed in breaking a notched bar of steel is not so well known in this country as it deserves to be. The test specimen used in this test is about 3/8 by 1/4 by about 11/4 in., notched with a hack saw on the lower side to cause the piece to break at a fixed point. A weight of 10 kg. falling 4 m., and provided with a knife or. chisel which strikes the specimen, breaks the test piece by impact. The residual force in the falling weight after it has broken the specimen is recorded by a suitable device, and the difference between the total energy and the residual energy of the weight (in kilogrammeters) is the force consumed in breaking the specimen. An experience of several years with the Fremont testing machine has shown its great value in readily detecting brittleness not revealed by tensile testing or slow bending testing. In this paper it is proposed to discuss (1) the supersensitiveness of the test as applied to cast steel and (2) its value in revealing the effect of heat treatment under certain conditions.

Jan 7, 1913

By Solomon J. Salat

During the major expansion of the Inspiration smelter, which took place in 1973, the bulk material handling system underwent a matching expansion in order to move the required materials. Inspiration is the first smelter worldwide to employ electric smelting in conjunction with the use of Hoboken converters (1), (2). The installation includes a 51 -MVA electric furnace, five 4.25m (14-foot) diameter Hoboken converters, rotary dryer, bedding plant, acid plant, heat recovery steam plant, and gas and dust handling system. See Figure 1, Plot Plan. As of today, the 51-MVA electric furnace is the world&apos;s largest in the smelting of copper. Engineering design for the installation was per- formed by Treadwell Corporation of New York. The task of designing the conveyor system was complex because the system had to be installed while the smelter was operating and with minimum plant shutdowns, and it had to serve both the existing and the new smelter. Existing conveyors were redesigned where necessary and incorporated into the new conveyor system. See Figure 2, Flow Sheet. The system encompasses the handling of such diverse materials as wet and dry copper concentrates, cement copper, silica flux, cold dope, and concentrate and flue dust.

Jan 1, 1979

By Larissa Carolina Ferreira

O impacto das atividades do setor de mineração sobre o meio ambiente tem levado a estudos visando, tanto à utilização racional dos recursos naturais, quanto o tratamento de efluentes gerados durante os processos. A caracterização de efluentes é uma etapa importante, podendo apontar erros nos processos de beneficiamento, parâmetros em desacordo com a legislação ambiental e guiar etapas de desenvolvimento de técnicas do tratamento. Este trabalho consiste na caracterização de um efluente da etapa filtragem de uma mineradora de minério de ferro do quadrilátero ferrífero comparando os valores encontrados com as exigências da norma CONAMA 357/2005 e 430/2011, de forma a enquadrá-los na categoria de águas doces classe 1 e de lançamento de efluentes. O pH encontrado (9,8), turbidez (2133 NTU) e sólidos sedimentáveis (28mL/L), estão fora dos padrões permitidos e mostram grandes problemas em relação aos sólidos presentes na amostra. O diâmetro médio das partículas (8,54µm), indicou a predominância de partículas ultrafinas de difícil sedimentação. Os elementos majoritários Al, Fe, P e S, 0,296; 1,6; 0,218 e 26,5 mg/L, respectivamente, também apresentaram valores acima do permitido para água doce classe I. As análises indicaram que o efluente necessita de tratamento prévio para posterior descarte.

Aug 16, 2017

By Kristine Bruce Wanderley

A lixiviação com ácido sulfúrico de minérios lateríticos resulta na geração de enormes volumes de rejeito que são encaminhados para barragens de rejeitos. Todavia, é possível recuperar os metais perdidos e contidos nas barragens. Dentre os metais presentes no rejeito está o magnésio, que pode ser removido por cristalização a alta temperatura. Fatores como temperatura, pH, agitação e tempo de residência podem afetar o produto final e remoção do magnésio da solução. Portanto, o presente estudo propõe avaliar a influência do pH na remoção de Mg2+ de uma solução sintética e analisar a morfologia dos cristais formados. A técnica empregada foi a cristalização a alta temperatura e pressão, realizada em um reator sob pressão. O pH foi variado na faixa de 1-5 utilizando-se H2SO4 1M. A temperatura, tempo de residência e agitação foram mantidos constantes a 230°C, 5 horas e 1000 rpm, respectivamente. A solução residual foi analisada por cromatografia de íons e a morfologia dos cristais por MEV-EDS. A maior remoção do Mg+2 da solução foi em pH 5,57 e a morfologia do produto é favorecido nesse pH. Abaixo desse pH os cristais formados apresentaram morfologia esférica.

Oct 30, 2017

By G. Bourque

Early in the design stage of their new concentrator for the Mount Wright Plant, Quebec Cartier Mining decided to use a process computer for total control of crushing, grinding and concentrating. A map of the area is given in figure 1 and a view of the plant in figure 2. Although the use of process computers is not a new idea in petrochemical and chemical industries, their use in the mining industry is very limited. We innovated in using the computer, not only for data logging, as we have seen in some other plants, but a sole operator located in the administration building, starts and stops mill lines, crushers, load-out system, tailings, thickeners, etc ... by means of a CRT console. Our process is fairly simple as can be seen on the schematic process flow diagram (figure 3). .The ore, carried by 136t diesel electric trucks, is dumped through ore pockets onto two primary pan feeders. The feeders supply two 1,52mx2,79m gyratory crushers which reduce the ore to minus 20,32 cm. Each crushing line have a capacity of 5600t per hour and feed a shuttle conveyor distributing the crude ore into six silos.

Jan 1, 1979

By T. Clinton Taylor

QUALITATIVELY, galena (native lead sulfide) reacts with aqueous solutions of the xanthates,1 and has its surface sufficiently altered so that there is a tendency for air bubbles to attach themselves to the mineral crystals where there was no such effect before the treatment. This property is utilized in froth flotation operations where the mineral sulfide particles are raised into the froth and the gangue whose surface is not altered remains behind. The results of a study of this reaction were reported" recently and certain tentative suggestions about the interaction of galena and the alkali xanthates were offered. In this paper, there is set down the results of a detailed quantitative investigation of the ions involved in this inter-action with a view to finding out more about the condition existing imme-diately at the surface of a crystal like a heavy metal sulfide after treatment with an organic reagent. Past experimental experience showed that finely ground galena shaken with aqueous potassium xanthate abstracts xanthate ion and at the same time sulfate ion, reducing ions of the type (SmOn)= where the ratio of m to n is less than 4:1 (as in sulfate), sometimes hydroxyl ion are thrown into solution.,

Jan 1, 1933

By Hampshire MJ

The tailing retreatment project rated at 10 000 t/day commenced operations in October 1982. The operation consists of dredging, feed preparation, cyanide leaching and carbon-in-pulp (CIP) gold recovery followed by Zadra atmospheric stripping and electrowinning. For the first two years the operation was adversely affected by excessive cyanide consumption and low gold extraction. Investigations demonstrated that the very fine, or slime, fraction of the tailing was the dominant consumer of cyanide and dissolved oxygen. The plant flowsheet was subsequently modified by inclusion of 80 - 100 mm dia. cyclones for slimes separation and a 31 m dia. thickener for water recovery. Treatment of deslimed feed in the CIP plant has reduced sodium cyanide consumption from an average 1.85 kg/t to 1.15 kg/t. The reduced oxygen consumption by the CIP plant feed has resulted in higher dissolved oxygen levels, frequently reaching supersaturation after 4 to 5 h contact time. This has allowed much improved gold extraction from the existing CIP plant capacity. Gold extraction from the mixed pyritic siliceous tailing has improved from an average U prior to desliming to a current 57%. Investigations are continuing on the recovery of gold from the discarded slimes.

Jan 1, 1986

By James R. Hein

Ferromanganese oxyhydroxide crusts (Fe-Mn crusts) precipitate out of cold ambient seawater onto hard-rock surfaces at water depths of about 600-4000 m throughout the ocean basins. Fe-Mn crusts concentrate most elements in the Periodic Table above their mean concentration in the earth&apos;s crust (continental plus oceanic crust), except for the major rock-forming oxides and also notably gold and palladium. Tellurium is concentrated greater than any other element relative to its earth&apos;s crust mean (about 1 ppb). For example, mean contents of the elements heretofore known to be most enriched in crusts, Mo, Tl, Sb, Co, Mn, Bi, As, Se, and Pb are enriched 100 to 1000 times over their earth&apos;s crust mean, whereas the mean Te content in Fe-Mn crusts is enriched about 50,000 times. However, the distribution of Te in the earth is poorly known. Estimates of the mean Te content of the earth&apos;s crust range from 0.36 to 10 ppb, with 1 ppb being the most commonly cited mean content (compilations in Levinson, 1974 and Govett, 1983). If we took the highest estimate of 10 ppb, then Te would be enriched in Fe-Mn crusts five times more than the next most enriched element, or 5000 times the estimated maximum mean earth&apos;s crust.

Jan 1, 2000

By C. G. Cunningham

The Marysvale volcanic field of west-central Utah contains large areas of argillically altered rocks (fig. 1) that, in turn, enclose smaller areas of fine-grained, medium-grade, replacement alunite deposits and coarsely crystalline, high-grade vein-type alunite deposits. The largest replacement alunite deposits are [ ] located peripheral to a 23-m.y.-old monzonite stock called the Central Intrusive (fig. 1). The deposits formed in near-surface, highly oxidizing environments at the tops of hydrothermal plumes that were spaced irregularly around the stock. The deposits are horizontally zoned from alunitic cores through kaolinitic to propylitic envelopes. Vertically, characteristic alteration minerals progress from a pyrite-propylitic alteration assemblage at the base, upward through alunitic, jarositic, and hematitic assemblages to a flooded silica cap as shown on figure 2. The silica caps are cut by hydrothermal explosion breccias. d34Sso4 values of + 11.5 to + 15.4 permil indicate that sulfur in the hydrothermal plume was derived from underlying Mesozoic evaporites. The sharp upward transition from pyrite- propylite to alunite probably marks the paleowater table, and the top of the flooded silica cap represents the paleoground surface. Basin-Range extensional tectonism began shortly after alteration, and buried the replacement alunite deposits in basins beneath sediments eroded from uplands. The deposits were only recently exhumed.

Jan 1, 2013

By C. P. Lazzara, R. W. Pro, A. C. Smith

The U.S. Bureau of Mines conducted a study to evaluate the effectiveness of automatic water sprinkler systems in the extinguishment of incipient conveyor belt fires under ventilated conditions. Large-scale experiments were conducted using a double strand conveyor belt configuration. Standard response, pendent-type sprinklers, with activation temperatures of 100°C, were installed above and between the two strands of belting, in accordance with Federal standards for sprinkler system installations in belt drive areas. Experiments at airflows of 1.1 and 4.6 m/s showed that the sprinklers activated later, the peak heat release rate was larger, and more betting was consumed at the higher airflow. In experiments with 74°C, fast response, directional sprinklers, the sprinklers activated at the same heat release rate for both high and low airflows, but the peak heat release rate and amount of bett consumed was slightly higher at the lower airflow. Experiments were also conducted with 100 °C, standard pendent sprinklers installed above the top belt, in accordance with the National Fire Protection Association (NFPA) Standard 123 for sprinkler system installations in conveyor belt drive areas in underground coal mines. In these experiments, the heat release rate and amount of betting consumed was larger at the higher airflow.

Jan 1, 1995

By Mark S. Dunsbier, Steven J. Schatzel

Large roof outbursts began occurring in November 1986 at Domtar&apos;s Sifto Salt Mine in Goderich, Ontario, Canada, working the bedded Salina A-2 Salt unit. The outbursts, measuring about 13-20 m in diameter, released high concentrations of methane from cavities that extended into carbonate roof units. Spontaneous ignitions of methane gas during an outburst seriously burned a mine technician. The Canadian Ministry of Labour contacted the U.S. Bureau of Mines for technical assistance to aid in mine managements1 efforts in alleviating the problem. Initial gas content determinations of salt samples from the outbursts by acoustic test methodology revealed no methane enrichment. In- mine core drilling and subsequent methane content testing indicates the main source of methane in overlying roof units. Drilling the roof units demonstrated the potential of draining methane from areas showing signs of impending outbursting and alleviating the danger. Three mechanisms are considered the most likely means by which methane was introduced to the mine environment. These are (1) hydrocarbon gases released from brines, (2) gas transport along horizontal bedding planes or gas accumulations in bedding separations, and (3) mining-induced fracturing. The abundance of higher hydrocarbons in gas yielded by non-evaporite rock samples from the Goderich mine may be indicative of a former association with liquid petroleum.

Jan 1, 1989

By D. B. Sikka, R. B. Bhappu

Porphyry-type copper-molybdenum (Cu-Mo) deposits typically occur in the Phanerozoic rocks and have been well-documented. During the past two decades, a number of porphyry-type Cu-Mo deposits that range in age from 1055 Ma to 2970 Ma have been identified in the Precambrian rocks of Australia, Canada, China, Finland, India. Namibia and Zambia. The Malanjkhand porphyry copper deposit M.P., India is estimated to contain 789 Mt (870 million st) averaging 0.83% copper (mill headgrade); 0.004% molybdenum; 0.2 g/t (0.006 oz/st) gold; 6 g/t (0.175 oz/st) silver and a cap of 7.5 Mt (8.2 million st) of oxide ore averaging 0.8% copper. The economic potential of the expanded copper mining milling, smelting and refining complex is expected to yield cathode copper 118.6 kt (130,700 st); molybdic oxide 830 t (914 st); gold 1.9 t (61,732 oz); silver 46.6 t (1.5 million oz); sulfuric acid 240 kt (264,500 st), copper from leach dumps 11.5 kt (12,600 st); nickel 24 t (26,400 st); cobalt 84 t (92,600 st); bismuth 16 t (17.6 st); selenium 48 t (53 st), tellurium 4.8 t (5.3 st).

Jan 1, 1995

By Diane F. Baker, Cathy Aimone-Martin

A series of small-scale explosive experiments were conducted in a perlite mine near Socorro, New Mexico. These experiments were a joint effort between Los Alamos National Laboratory, New Mexico Institute Of Mining and Technology, Southern Methodist University, and Defense Nuclear Agency. The purpose of these tests was to measure the changes in the shock wave and seismic coupling as a function of depth of burial and structural setting. The size of the explosive charges ranged from 1 to 68 kg. Over 1150 measurements of velocity and acceleration were made on thirteen experiments using three component sensors. The sensors were placed to maximize the azimuthal coverage as well as to provide data at a variety of ranges from ~1 to 130 m A few far field measurements were made at ranges of ~2Êkm. While the bulk of the measurements were made on the surface, high g accelerometers were placed in one instrumentation borehole to provide some free-field measurements. Preliminary results indicate that significant differences in the amplitudes of signals can occur when the location of the explosive charges are changed by only meters. Part of the observed difference is attributed to variations in the rock immediately adjacent to the charge affecting the shock coupling; and part to the effects of the site characteristics.

Jan 1, 1994

F. C. LANGENBERGW.*at 8ertoivn,M ass. (written cliscussiont).-I am inclined to the view that the change in physical properties encountered in the material with which the authors are working is due to the relief of internal strains. The statement, on page 1.098 of their paper, calling attention to the fact that this phenomenon disappeared when the material was rolled into 1 7/8 -in. square billets is of particular interest. It is certain that the internal strains set lip by cooling in a small billet of this size would be much less than those produced in a billet having a larger cross-section cooling under the same conditions. The statement that the physical properties of a given test bar were materially changed by standing has been brought to my attention in connection with the testing of gun forgings. I have made a number of observations on forgings produced at Watertown Arsenal to ascertain whether any change in ductility was produced by the aging of the test specimens. The results were always negative, but this can be explained by the fact that ii gun forging is generally a forging that has been quenched and subsequently drawn at a relatively high temperature.

Jan 10, 1919

No. 526.-At liberty about Mar. 1, 1919. Just returned from France, a Captain of Engineers. Member A. I. M. E., A. I. E. E., 35 years old, technical education. Last six years of civil life as electrical engineer, master mechanic and superintendent of construction with large mining company. Salary expected, $3600 per year. No. 535.-Member, &apos;mining engineer, technical graduate, age 34 years, experience as engineer for coal companies. Three and one-half years with one company and five years with another. Have good recommendations. Recently honorably discharged, First Lieutenant, U. S. Army. Desires position, preferably in West. Salary last received, $175 per month. No. 555.-Metallurgical engineer having 18 years&apos; experience in positions from chemist to manager, specializing in the smelting of copper, gold and silver ores, and now returning to the U. S. Available about May 15. No. 556.-Manager or superintendent, member, technical graduate, age 44, married, desires position. Good references, 18 years&apos; experience in positions of responsibility and administration. Familiar with development, mining, milling, operation, construction and management. Available on short notice. , No. 557.-Member, technical education, married, age 30. Five. years&apos; experience in construction work, four years superintendent of mining and milling operations. Looking for wider experience. Free Apr. 1.

Jan 4, 1919

By Charles Clayton

A study of the literature shows that the greater part of research work on annealing of cold-worked iron has been for the purpose of studying the effect on grain-size and properties other than hardness. No reference has been found of experimental work of the same nature as that explained in this short paper. The material used throughout was Vismera iron, an iron containing 0.03 carbon and made several years ago by the Inland Steel Co. One-half inch stock was cut into cylinders ¾ in. long. The cylinders were then compressed for 60 sec. in a Reihle testing machine under loads as indicated below: COMPRESSION, AVERAGE LENGTH, SERIES POUNDS INCHES 1 10,000 0.693 2 15,000 .599 3 20,000 .501 4 25,000 .426 5 30,000 .378 6 35,000 .351 7 40,000 .311 Fig. 1 shows these cylinders after compression. Each series con¬sisted of 17 specimens lettered 0, B, C, D, E, E:, G, H, I, J, K, L, M, N, P, Q, and R. One specimen of each series was reserved for study of the properties in the cold-worked condition. The other specimens were annealed in a Hump furnace for ½ hr. at the following temperatures:

Jan 2, 1926

By R G. Barker, N Mortimer

In New Zealand, platinum group metals (PGM) occur in three main geological environments of economic interest: layered mafic igneous complexes, the Dun Mountain Ophiolite Belt, and in association with placer gold deposits. Most of the layered mafic complexes with PGM potential occur in the Median Batholith. These include the Longwood (Permian), Bluff (Permian), Riwaka (Devonian) and Rotoroa (Jurassic) igneous complexes. Exploration of the Longwood Complex discovered PGM associated with gabbroic rocks. Best assays to date include a 1 m drill intersection of 1 g/t Pt + Pd and float rock with 3.0 ppm Pt and 3.3 ppm Pd. The Greenhills complex at Bluff consists of basal dunite overlain by wehrlite and gabbro. PGM occur with chrome spinel in the basal dunite and Pt geochemical anomalies have been identified associated with the wehrlite-gabbro contact zone. The Greenhills complex has some similarities to Alaskan-Ural type complexes.Reconnaissance exploration in the Dun Mountain Ophiolite Belt has identified PGM geochemical anomalies, but no follow-up work has been carried out. During the late 1800s and early 1900s, PGM were recovered as a byproduct of placer gold mining in Southland. Placer gold prospects with PGM potential include the Waiau River, deposits flanking the Longwood Complex and some Southland beaches.

Jan 1, 2002

1. Book review . Australasian coal mining practice, edited by C.H. Martin. Reviewer: R.B. MacGilIivray This book is an extremely comprehensive coverage of coal-mining practice in Australasia, the countries covered being Australia, New Zealand,and Papua New Guinea. 2. From The Institute of Metals The folowing are available from The Institute of Metals, 1 Carlton House Terace, London SWl Y 5DB. Physical and elastic characterisation, edited by M. McLean. 1989. 228 pp. £25.00. High nitrogen steels, edited by J. Foct and A. Hendry. 1989. 461 pp. £49.50. Proceedings of the First International Calcium Treatment Symposium. 1988. 116 pp. £15. New cored-wire injection techniques, particularly as Design for recyc/ability, by Michael E. Henstock. 1988. 150 pp. £15. Solidification processing. 1988. 549 pp. £45. Marine engineering with copper-nickel. 1988. 103 pp. £18. Characterisation of High Temperature Materials. 3. New journal FMJ International Publications Lid have announced a new quarterly publication, Aluminium Today. 4. Other new publications Algorithms in real algebraic geometry, edited by Denis S. Arnon and Bruno Buchberger. London, Academic Press, 1988. 274 pp. £15.95. Proceedings, Foundry and Heat Treatment 88. R150 per set of 5 volumes, or R40 per volume.

Jan 1, 1989