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By F. Qiming

By means of flotation experiments, potential-pH diagram, electrochemical testing and X -ray photoelectronic spectrum (XPS), the main factors (the thermodynamics and the property of surface products) influencing the separation of sulfide minerals (such as galena and chalcopyrite) in the collectorless flotation are studied. The actual conditions (Eh, pH) of separation are not conformable to the results of thermodynamic calculation. The kinetic behavior of oxidation of sulfide minerals and the property of oxidation products are the decisive factors of the separation of sulfide minerals in the collectorless notation.

Jan 1, 1992

By Juan L. Luque Lanza

Durante las fases de minado como la exploración, desarrollo, preparación y explotación de una zona mineralizada, surgió la necesidad de clasificar geomecánicamente el terreno a través del uso los conceptos básicos de la mecánica de rocas y la integración de dicha disciplina al planeamiento del minado de una mina subterránea. Por ello, el presente texto describe el proceso de esta metodología que consiste en la clasificación del terreno según los grupos de similar comportamiento y la elaboración de planos geomecánicos, con la finalidad de encontrar la relación existente entre el tiempo límite y el espacio activo para una excavación subterránea, diseño y cámaras pilares en la mina subterránea de Yauricocha.

Aug 26, 1988

By L. M. Sun

Baotou Baiyunerbo Mines Location in Inner Mongolia is a famous deposit of iron mineral and rare earth mineral accreting. The iron ore has very complicated ingredients and minerals composing. In the mine, there is not only magnetite ore but also hematite ore, so that it is impossible for high grade iron concentrate to adopt single wet low-intensity magnetic separation or high-intensity magnetic separation to concentrate iron mineral. Because of mixing the magnetite with hematite mineral in feed ore, recovery of iron of magnetite production system in the mineral processing plant is less than other mineral processing plants. Therefore, the research for increasing recovery of iron of the magnetite production system in the plant was undertaken. The paper presented the research for using dry magnetic separation to increase recovery of iron concentrate of the magnetite production system in the plant. It mainly includes dry magnetic separation test and wet magnetic separation and reverse flotation test. The test results indicated that dry magnetic separation is a important way to improve the feature of feed ore of the magnetite production system and to increase the recovery of iron. The recovery of iron may increase from about 70% to over 80%. The research also presented optimum operation parameters of the dry magnetic separator and the separation flowsheet. In conclusion, using dry magnetic separation to treat with feed ore of the magnetite production system in the plant to increase the recovery of iron is a feasible technique. The research present a new way for the mineral processing plant to made technology innovate to increase the recovery of iron concentrate of the plant in future.

Jan 1, 2014

By W. R. Lindsay

Considerable attention has of late been given to the blasting of large amounts of ore in one operation, on account of the saving in labour and explosives and consequent low cost per ton, and also on account of the additional safety to employees. The blast here described, at the Hidden Creek mine. at Anyox, B.C., is not necessarily unique either in size or methods employed, but some interesting p10blems were encountered and the solutions of these may be of interest to others engaged in similar work. The ore consisted mainly of old scope-bottoms and sill pillars, although there also were some braces and parts of vertical pillars included. Some of the stope-bottoms were overlain by caved waste, and one of the problems was to break them in such a manner that the maximum amount of ore could be recovered without serious dilution with waste. The ore blocks, designated as the 385 silt and the 7 A-103 blocks, were under preparation for blasting for over a year, as conditions permitted. This work consisted in drilling long machine drill holes, varying in length from 14 to 20 feet. These holes were drilled with the Numa detachable bit, made locally, starting at 2~-inch diameter and bottoming at 2 inches for the longest length. The long hole drilling was used in the thinner sections of the area. For the stronger, thicker portions, powder drifts (3 ft. by 4 ft. in section) were driven for the powder charges. Reference to the plan and sections (Figures 2 co 8 inclusive) show the relative location of these, as well as the long drilling. The amount of explosives used in the powder drift charges averaged 0.25 pounds per ton of estimated burden, varying from 0.2 to 0.3 pounds per ton.

Jan 1, 1934

By S. C. Nordeng

The program described in this paper is primarily a test of the possible utility of multiple regression in ore search, It was carried out as a cooperative project between White Pine Copper Company, the Institute of Mineral Research and the Department of Geological Engineering of the Michigan College of Mining and Technology. The authors wish to thank Dr. Cleaves Byers, Associate Professor of Mathematics, MCM&T, and Mr. Robert DeBaubien, Graduate Student in Mathematics, MCM&T, for their work in programming the project for the computer,

Jan 1, 1964

By X. M. Chen

The selection of leach reagent mainly according to the ratio of useful mineral to gangue in mineral raw material and the structure of mineral raw material. Besides that the price of reagent, the capability of reagent decomposing mineral and its causticity on equipment is also supposed to be in regard. On common conditions, the scandium content in mineral raw material is low, even Sc concentrate of specimen-Yunnan rare earth ore which contain Sc used in this experiment only is 148 g/t. Moreover, in enlarging scale experiments the content of scandium in leach liquid is only 3.6g/t, meanwhile various and complicated impurity existing in it. At present, both domestic and abroad has succeed in enriching scandium from vitriol solution, while enriching scandium from hydrochloric acid only has been studied in some minority units, which is not reported to be practical in industry. Therefore, this item offer a new research issue on Sc?s extract, which is as well as the task of this research. Spectrum analysis, chemic component analysis and scandium content have been made in main mineral measurement on rare earth with Sc in the paper. Based on characters of sample, select hydrochloric acid, vitriol and nitric acid as leach reagent and make different blueprints to accomplish the experimental research about selecting leach reagent. In the aspect of rare earth leach scandium leach density is researched, leach liquid to solid rate, leach temperature, leach time, leach granule rate and leach solution. This experiment claims that in the optimal experimental ambience, leach rate of vitriol is 58.18%, the leach rate of nitric acid is 50.73% and the leach rate of hydrochloric acid is 59.34%. Among them, hydrochloric acid has the best effect, therefore this experiment choose it as the leach reagent.

Jan 1, 2014

By T. Fujita

The incinerated bottom ash includes titanium oxides and a small amount of chromium oxides. Initially, 89 % of chromium was removed from ash at magnetic flux density at several stages of wet magnetic separation from 0.05 T to 6 T. The bottom ash from an industrial waste incineration process includes about 10 % of TiO2. The minerals that contain titanium are rutile and perovskite. These minerals are paramagnetic and show low magnetic susceptibility, therefore, the high magnetic field strength, created by a superconducting magnet, is necessary to capture these minerals. At the first stage of separation, a magnetic field strength of 6T was applied in order to attract the particles that contain iron oxides to the higher magnetic field region. At the second stage of separation, the magnetic capture rate of weekly magnetic particles decreased with increasing the magnetic susceptibility of the aqueous solution (i.e. the medium for dispersing the particles) in order to separate the highly magnetic materials. The para-magnetic salt such as ferric chloride was dissolved in the water to increase the magnetic susceptibility of the medium. After a two-step wet HGMS with superconducting magnet, the grade of TiO2was increased from 10 % to 28 % with a recovery of 64 %.

Jan 1, 2014

Public perceptions about coal remain neutral to negative But gains are slowly being made as the public becomes more aware of coal as ?abundant, affordable, and increasingly clean?

Jan 1, 2006

By P. A. Wasson

Drill cores from 15 holes in the West Central Mesabi Range were studied as part of the Lake Superior iron resource investigation begun in 1957 by the Bureau of Mines. Chemical, petrographic, and metallurgical analyses were made to determine grade, mineralogy, magnetic characteristics, and response to beneficiation. Data in this report were developed to provide a better under-standing of the nature and character of low-grade iron ore occurrences, to measure potential of usable ore, and to provide a basis for comparison with bank samples previously taken in the same general area. The average iron content of 4,445 feet of core was 31.8 percent. Iron oxides present were hematite, goethite, and magnetite; the gangue minerals were chiefly quartz, iron silicate, and iron-bearing carbonates.

Jan 1, 1962

By N. B. Prenn

Case Studies in Open Pit Design Using Whittle 4D will be discussing the following four examples: 1) Optimization of process plant design using Whittle 4D as a sizing tool. In this case, the home office and project team had different views of the size of the final project. The home office wanted to reduce the size of the project to reduce capital expenditure, while the project team suggested a larger project. Whittle 4D was used to determine Net Present Value and Internal Rate of Return using the Whittle scheduler (FDAN) to schedule many alternatives, and calculate the NPV and return for each alternative. 2) Comparison of pit optimization methods: Lerchs-Grossman vs floating cone. Many pits are developed based on floating cone economics. A comparison of methods in one large gold mine resulted in the stripping ratio of the pit being reduced by 10% in the Whittle 4D optimization as compared to the floating cone optimization. 3) Pit optimization to determine if a new mill is justified. A large heap leach gold and silver mine needed to determine if a new mill was justified. The planning and scheduling would take several man months if completed without pit optimization and scheduling software. Whittle 4D software proved to be very effective in providing optimized pits and a mine schedule in a short time frame. 4) Pit optimization to determine how to mine and size. Open pit optimization determined where the underground operation should start, and whether the material should be processed by milling or heap leaching. One of our clients asked for help in determining where the pit should end and a new underground operation start. We used Whittle 4D to help determine where the pit should end and where to go underground. In addition the operation needed to determine how to process the material.

Jan 1, 1996

By L. X. Yu

As is known, the oxidized antimony and antimonate are hard to treat. A new combined mineral processing flowsheet which is controlled in grinding and classification ?bulk floatation?gravity separation is adopted to dispose of gravity-separated tailings (antimony content: 1.48%; oxidization rate: 68.92%) in Muli Antimony Mine, the grade of floatation antimony concentrates is 32.64%; the grade of gravity-separated antimony concentrates is 26.99%; the combined grade of floatation and gravity-separated antimony concentrates is 30.85%, and the total recovery of antimony is 70.64%. Adopting the new mineral processing technique have solved the problem of over grinding of antimony ore by controlling grinding and classification, recovering effectively the sulfide antimony and the easy floatable oxidized antimony of fine size by bulk floatation, recovering effectively the oxidized antimony which is hard to float by classified gravity separation. This is a great breakthrough in the mineral processing technique of the recovery of the oxidized antimony. At present, favorable economic benefit has been obtained from the application of this processing technique in Muli Antimony Mine.

Jan 1, 2014

By H. M. Smith

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Jan 1, 1927

By Robert S. Penczak

Red Lake Gold Deposits ? Descriptive Classification (modified from Pirie, 1982) VHR Au -- Volcanic-hosted (vein & wall-rock) replacement Au deposits ~93% of camp production Q-(T) Au -- Quartz-(tourmaline) vein Au deposits ~7% of camp production Quartz-sulphide Au deposits Porphyry-hosted sulphide Au deposits Current & Significant Past Producers Camp Production 21.6 M oz / 672 tonnes Au Other Deposits / Occurrences (Intermittent Exploration

Apr 1, 2005

By Singareddy R. Reddy, Ramana G. Reddy

"The Margules equation is used for interpreting excess Gibbs energy of several ternary systems. An expression for the activity coefficient of a dilute solute, 2(oxygen), in a binary solvent 1-3 is derived. It is used to calculate the logarithmic activity coefficient of oxygen in Pb-O-Gu, Pb-O-Bi, AgO- Sn, Pb-O-Sn and Ag-O-Pb metallic systems. Self interaction parameter of the solute is derived from the partial Gibbs energy of solute using constant compositional path. The derived equation is used successfully to deduce the self interaction parameter of oxygen in Pb-O-Gu and Pb-O-Bi metallic systems. The predicted thermodynamic parameter data i.e activity coefficient and self-interaction parameters are in an excellent agreement with the experimental data and also our predictions are far more accurate than the predictions made by other models.1 IntroductionThe nature of solute interactions such as oxygen, nitrogen and sulfur with the metallic solutions are important for a number of chemical and metallurgical processes. Several theories [1-23] have been developed to evaluate fundamental thermodynamic properties of solutes constituting two elements. The activity of solutes has been calculated using statisticalor quasi- chemical approach.Wagner's [4] Ideal Solvent Model is based on one energy parameter to describe the compositional dependencies of the activity coefficient of nonmetallic solutes such as oxygen in binary metallic solutions. This model depends on a constant energy of interaction for the exchange of atoms from the coordination shell of an oxygen atom to the shell of an interstitial site and cannot account for properties of strongly interacting systems [4]. Therefore, several attempts have been made to improve the Wagner's model for the strongly interacting systems. [10-16]."

Jan 1, 1996

By Adolfo López Romero

El presente texto describe un sistema de prioridades de inversión en la minería, donde se solucione el problema de cálculo para uno de los proyectos en ejecución. Un "proyecto", puede ser descrito como el insumo de un conjunto de factores productivos, cuya consecuencia es obtener uno o varios productos. Las "cifras de prioridad" indicarían el orden de urgencia de un cierto proyecto, así como el límite entre proyectos que deberían o no ser ejecutados. La "cifra" contiene la suma de todos los factores mensurables. Sin embargo, se debe considerar los factores cualitativos.

Jul 1, 1962

By Robert M. Cox

A thorough geological engineering investigation is required before surface lands overlying abandoned underground mines can be safely recommended as building sites. The major problems confronting the geological engineer are assembling accurate geologic and mining information and developing an accurate rock mechanics model of the situation. A successful investigation requires a combination of technical expertise in rock mechanics and engineering geology tempered with practical engineering judgment. The results of a good study are not always favorable to the prospective builder.

Jan 1, 1975

Minerals and Metals Group (MMG) Century mine (Century) is a large open-cut mine in northwest Queensland approximately 2.5 km long, 1.5 km wide and 240 m deep, with an ultimate pit depth of 320 m. In 2009, the mine experienced three failures which began as small failures, and progressively developed into significant multi-batter failures. The incidents were managed by a combination of analysis, redesign and practical management to achieve positive outcomes for the mine. On the south wall of the mine, a series of batter-scale wedge failures occurred in December 2007. Analysis of structure orientations and design changes aimed to minimise the risk of failure extending over multiple batters, while accepting a risk of further small-scale failures. Design changes were constrained by a culturally sensitive area (CSA) located south of the wall. As mining progressed, shallow wedge failures developed over multiple batters and cracks were observed 60m back from the pit crest, indicating that a large-scale wedge failure was developing. Movement increased in January 2009 as a result of significant rainfall. After considering several design options, the area was stabilised by a cut-back of the wall. Two multi-batter failures also occurred on the north wall as mining progressed through a structurally complex area. Both north wall failures began as small failures that progressively developed, and required a redesign of the wall below as well as practical management of safety aspects. The complex structural geology was difficult to predict ahead of mining, and required geotechnical input into design changes as mining progressed. All three failures potentially had significant impact for ore recovery, and were managed by a combination of analysis, redesign and operational management have resulted to achieve positive outcomes in a challenging mining environment.

May 1, 2010

By W. H. MacLean, P. J. MacGeehan, A. J. Bonenfant

"The Norita deposit is an Archean volcanogenic-exhalative Fe-Zn- Cu sulphide accumulation of the distal type, consisting of six overlapping stratiform massive sulphide lenses, interbedded with exhalative cherts and thin pillow basalt flows, which formed down-topographic-slope from a mineralized hydrothermal discharge zone in the Norita rhyolite. The sulphide lenses are of two main types: channel-fill deposits such as the Main Zone and Main Zone West, composed of intricately layered pyrite-sphalerite-chert, which formed by the dynamic down-slope transport and re-deposition of sulphide exhaled from the vent zone; and stratiform lenses such as the Cu-rich A-Zone and A-Zone West, which formed even farther down-slope, in basinal depressions flanking the dome. Although rotated into a vertical position by folding, the sulphide lenses are otherwise essentially undeformed and contain a wide range of preserved primary sedimentary structures.Of prime importance in exploration has been the recognition that the formation of the distal sulphide lenses was controlled by submarine paleotopography, and that it is possible to approximate the sea-floor paleotopography using variations in the thickness and strike extent of the interbedded volcanic rocks. This has proved to be a major and successful exploration tool in the search for further sulphide mineralization in the mine, and offers prospects for use elsewhere in the district."

Jan 1, 1981

By H. J. Fraser

LIKE a runner catching his second wind, the mining geologist in 1944 has had some opportunity to appraise the result of three years of active and intense search for the metallic sinews of war and peace. The war period has been one of physical activity and accumulation of new data but has not so far resulted in the announcement of any profound or revolutionary theoretical concepts or techniques. Most technical publications during the year have been either descriptive or statistical. A review of accomplishments during the war years, although affording some measure of satisfaction in individual cases or regarding production of certain metals or' ores, is far from justifying any feeling of complacency regarding the growth of the profession either in fundamental knowledge or in application. During 1944 an abundant supply of all metals and minerals flowed steadily to smelters and fabricating plants. Also, during this and preceding years, adequate stock piles for war needs, in view of the improved foreign and domestic supply situation, were accumulated in many metals in such quantities that the mining industry has become concerned not with the problem of supply but with the effect these accumulated stocks, if maintained, might have on the postwar market. These considerations culminated in the enactment by Congress of the Surplus Disposal Act, which, admittedly a tempo-

Jan 1, 1945

By S. A. Diatchkov

There is a misconception that mineral-project economic evaluations in the former Soviet Union are either nonexistent or very limited. This is not the case. In fact, there are at least two basic methods that can be utilized to evaluate the vast mineral resources of the Commonwealth of Independent States (CIS). Evaluation procedures are based either on a comparison to known projects, which may rely on limited available data, or on potential-profit calculations, which generally uses more extensive databases. Significant philosophical differences between these systems and those utilized in the Western world include the following: •Under the centralized-government system, the economic evaluation of a mineral project was based on artificially determined mineral prices and costs. Every ten to 12 years, prices for concentrates and metals were established by the Council of Ministers and remained unchanged until the next reconsideration of prices .

Jan 1, 1995