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By Bernard J. Reddy

This paper describes in detail the economic forces affecting cobalt supply, demand, and prices. The major factors that will determine the growth or decline in the use of cobalt in each of its applications are discussed. The flows of cobalt from mine to refinery are described on a company-by-company basis. The paper concludes with a discussion of how the characteristics of the supply and demand sides of market interact to determine cobalt prices.

Jan 1, 1986

By G. Chambovet

Applied geophysical methods such as the surface seismic method have been applied for many years and in many places, mainly for oil exploration and to a lesser extent for mineral deposits? exploration in sedimentary basins. The seismic method fundamental is based on the variations of acoustic impedance in a layered earth model and such variations at each main geological interface create reflected waves that are processed and imaged in order to output a clear picture of the subsurface structure. The geology of South Africa was historically, and even until recently, considered as unfit for seismic exploration and the mines were always reluctant to spend any portions of their exploration budgets on these techniques. Hard rocks and high P-waves velocities were creating quite a hopeless model for any mine geologist or geophysicist (if any), unsuitable for the proper use of seismic waves to image their subsurface problems. Boreholes were considered the only reliable tool to derive a geological image of the mine structural features and were linked sometimes with surface methods such as aero-magnetism. The obvious flaw of this methodology was the inability to derive a continuous image from a discrete set of measurement points. Surface 3D seismic is the tool that gives a reliable solution from the initial model extracted from the boreholes, as even the aero-magnetism mapping gives a flat image, unable to show any depth correlation from well to well. The first 3D surface seismic surveys were recorded in the early Nineties only for the gold mines of the Witwatersrand, after a series of serious new shaft sinking failures. The wrong geological locations of these shafts resulted in financial loss of several hundred million rands. The era of3D seismic just started in South Africa and till 1997, all seismic done in the country was for gold exploration with geological target depths close to the oil exploration average depth of investigation. A very important breakthrough was reached when the depth accuracy of the seismic image was tested in real scale as the stopes were surveyed. An error of amplitude of 20 m was usual when true depth was compared with the seismic image predicted depth and shape. This accuracy, completely unknown in oil exploration, started to gain supporters of seismic methods in the mining community but the cash problems and the concentration/disappearance of gold mines in the late Nineties, led to the belief that seismic would be just a very short exploration activity for the mining sector. ort exploration activity for the mining sector. But starting in 1998 with Impala, a tremendous and continuous 3D surface seismic activity occurred in the platinum mining sector. The seismic world got used to new terms such a Merensky and UG2, which have replaced the VCR and black reef. If the primary expectation of platinum surface 3D seismic was to determine and ascertain new shaft locations, as for the gold mines, the quality of seismic data led the mine geologists to require smaller and smaller imaging of geological objects. In addition to the main structural image, small faults, potholes, and shear zone were common expectations of platinum seismic. In a constant velocity environment, what saved the day was the sharp density contrast between the PGM reef and the embedding geology. A good contrast of impedance exists in the whole Bushveld and is sufficient to have enough reflected waves from the PGM main layers to build a high quality seismic image of the subsurface. Recent advances in technology have led in less than 10years to major improvements in the seismic acquisition by using high frequency vibrating seismic sources, but also in processing and interpretation. With these latest improvements, seismic can detect objects of 7.5 m size, either fault throws, flexures, etc. The PGM formations of the Eastern limb of the Bushveld Complex are now accessible for seismic imaging, with cost per square kilometre comparable to the borehole cost of the same surface unit. The economically acceptable seismic surveys can be used for UG2 structural imaging up to a depth of 210 m below surface. Linked with borehole information, 3D seismic today offers a wide range of information for mine development: structural imaging, small fault detection, pothole and shear zone identification. All users of 3D seismic have also used this technique as a tool in the process to qualify their mineral reserves and especially from the category ?inferred? to the category ?measured?. Junior mining companies, in the feasibility stage of their projects, are also quite eager to use seismic as a reserve certification tool, when they present financial statements to future potential investors. Junior mining companies, in the feasibility stage of their projects, are also quite eager to use seismic as a reserve certification tool, when they present financial statements to future potential investors. The current high demand on platinum, pushes the seismic towards new technologies to be implemented in order to improve the final image. Using surface and borehole seismic together or acquiring seismic surveys with multi-component receivers have been just introduced in South Africa. In less than 10 years, surface seismic by adapting its methods to the special case of the Bushveld, became a mandatory step in mine development and ore resources evaluation. As part of the ?seismic? world we are proud to be a major player the ?surge? of platinum exploration and production in these last years and we will certainly increase our synergy with the mine sectors in the exciting coming years.

Jan 1, 2006

By W. L. Cornell

The Missouri lead ores are the only domestic sources of cobalt presently being mined and processed for other materials. They represent the best short-term solution for meeting up to 13 pct of the Nation's strategic and critical cobalt needs from domestic sources. Presently, the cobalt is lost as an impurity in the copper, lead, and zinc concentrates and in the mill tailings because the technology to recover it with minium impact on present production does not exist. This paper presents results of research, built upon earlier Bureau of Mines laboratory research, to enumerate the problems encountered in cobalt recovery from the copper concentrate under actual mill conditions; to present alternative solutions to these problems; and finally, to describe the best available technology for cobalt recovery within the imposed constraints. Mineralogical analyses showed the cobalt present as a distinct mineral phase, predominately siegenite, amenable to a physical separation method such as froth flotation. Flotation was chosen for recovery because of easy adaptation by the mills. Unit processes of grinding, conditioning, and flotation were studied individually and in concert, and a series of continuous tests were run based on the parameters developed to obtain engineering data for subsequent economic analysis. Overall cobalt grades of 3.00 wt pct at a recovery of 64.0 pct were achieved.

Jan 1, 1987

By Jose F. Agapito

This paper describes part of a geotechnical program which was instrumental in obtaining information for the design of large oil shale pillars. The work was carried out during 1971 and 1972 in the experimental mine of the Colony Development Operation. Colony is an oil shale venture formed between Atlantic Richfield Company, Operator; The Oil Shale Corporation, Cleveland-Cliffs Iron Company, and Sohio Petroleum Company to conduct research and development in mining and retorting of oil shale. The property is located in the southern edge of the Piceance Creek Basin in northwestern Colorado, approximately 250 miles west of Denver. Mining was conducted by the room-and-pillar method in a 60-ft high portion of the Green River formation at a depth of 600 to 850 ft. Pillar dimensions are approximately 60 ft by 60 ft. The mine site is in the eastern face of the canyon containing the Middle Fork of Parachute Creek. The distance from the mine to the side of the mountain varies from 500 to 1200 ft, and its height above the stream floor is approximately 700 ft.

Jan 5, 1974

By Rollin A. Slater

The bulk materials handling industry has served silently for years as the skeleton structure and often the central system of nerves and nourishment for the body of basic production industries. During the past two decades, this body has undergone substantial growth and mutation to meet the surging demands of our national economy for more and better products. The steel industry has been prominent in this phenomena and plants of the sixties are as unlike the second war vintage as our current crop of basketball players differ from their fathers. Steel has kept pace with spiralling demand by innovation which has resulted in new processes and improved designs which generally yield greater production from fewer units. The supporting industry of materials handling has likewise improved its techniques and currently has a new stronger generation of equipment to perform its necessary supporting function. It has been my fortunate experience to have been instrumental in the creative stages of several new steel mills which are currently in conceptual design or actual construction. Drawing upon exerpts from this experience, this paper will describe a basic approach to the selection and application of modern bulk materials handling systems to an entirely new steel plant. Specific details of past work are not available for publication, therefore, the plant described herein is a composite of ideas and will be the new plant of the Hypothetical Steel Corporation which will be located on the lower shores of the Great Lakes.

Jan 1, 1967

By J. Loeb, R. Ramanathan, P. Cameron

All mining operations, including iron ore, maintain a focus of continuous improvement and asset optimisation in their operations. As all the operations in the Mine-to-Mill value chain are inter-dependent, available technologies that address efficiencies across the value chain are once again in the spotlight as companies are driven to improve productivity and maximise mine site profits to increase return on capital invested. Core to continuous improvement is the need to understand the baseline and the impact of changes to the process. In this paper, we discuss some of the key attributes in the mine to mill process, including their influence on productivity and cost, the need for direct measurement and areas where they should be applied. Many initiatives can be considered to improve mine to mill processes. Mining operations are planned and executed based on designs and models to achieve the operation’s objectives. However, there are many variables in the different parts of the value chain, such as blasting, material handling, crushing and screening. Measurement of the key attributes establishes the baseline for Mine to Mill (or Pit to Plant) performance which is necessary to understand the impact of any proposed improvements to the process design and execution and to monitor the outcomes on an ongoing basis to sustain the improvements that have been implemented. We have focused this paper on two types of measurement – blast movement and particle size of materials through the mine to mill process. Several innovative technologies are already available to measure these attributes and assist operations improve productivity and mine site profits.

Mar 2, 2022

By James McManus

The original analogue instrumentation at Lornex Mining Corporation to optimize the throughput by controlling the power drawn by the semi-autogenous mills was found to be inadequate because of the frequent changes in ore type. Although the trunnion bearing pressure of the mill was a crucial control criterion, it was not utilized in the original control scheme. After several plant tests of different types of analogue controllers were unsuccessful in finding any control equipment suitable for this application, it was concluded that a digital process control computer was required. Computer control strategy to optimize the grinding rate by controlling the power and the bearing pressure of the semi-autogenous mill was developed and a Fox 2 /30 computer made by Foxboro was selected. After six months of experimentation, it was found that the throughput was increased substantially by computer control.

Jan 1, 1978

In this issue, the Bureau of Mines announces the availability of the latest of its Mineral Perspectives series: ?MP-4, mineral Industry of Western Europe." This publication describes the mineral industries of 19 Western European countries. For readers unfamiliar with this new series, reproduced below and on the two succeeding pages, is the section dealing with the mineral industries of France. Information regarding acquisition of this publication is found inside the back cover of this issue. FRANCE France is a moderately important producer of minerals, including iron ore, coal, potash, fluorspar, and uranium. In addition, France is a significant processor of imported minerals, chiefly for its own consumption. In general, it has exportable surpluses only of a little iron ore (low-grade ore exported to Luxembourg) and some nonmetallics.

Jan 1, 1977

By G. J. C. Young

The paper describes the replacement of a conventional filtration, clarification and zinc precipitation plant by a carbon in pulp (CIP) electrowinning plant, with the objective of improving the recovery of gold from cyanide leached, acid plant calcines. The discussion covers the early laboratory studies to the design and erection of the full scale plant. Particular emphasis is placed on the problems encountered with commissioning and the strategies which were employed to solve them.

Jan 1, 1982

By F. S. Hoseinian, M. Irannajad, M. Safari

In this study, the effect of chemical interactions of materials used in ion flotation on the removal of Ni(II) ions from low concentration synthetic wastewater was studied. Sodium dodecyl sulfate (SDS) and ethylhexadecyldimethylammonium bromide (EHDABr) as collectors and methyl isobutyl carbonyl (MIBC) and Dowfroth250 as frothers were used. To investigate the effective parameters and interactions of them, 16 experiments including 6 level variables were performed by supporting DX7 software and on the bases of 2-level factorial method. In the first step, the tests were conducted in a Hallimond tube. The result showed that collector of SDS and frother of Dowfroth 250 had appropriate interaction with each other at pH = 3. In the second step, optimal results from the first step were evaluated in a mechanical flotation cell. The removal of Ni(II) ions increased by increasing the time of flotation and they have a direct relation with the water removal. The kinetics study shows that the order and the rate of removal of the reaction do not follow any of the zero-order, first-order and second-order equations. The flotation rate curve on the removal of Ni(II) ions will divide the separation process to two stages, a fast flotation rate at the first stage and a slow flotation rate at the second stage. Ni(II) ions removal was obtained 88% at the best condition.This study showed that the use of ion flotation was a very effective method for Ni(II) ion removal from industrial wastewaters.

Jan 1, 2016

By Pedro A. Netto, Giulio R. Altoé, Sergio N. Monteiro, Ygor M. Moraes, Frederico M. Margem, Gabriel O. Glória

Since environmental issues are becoming more and more important Worldwide. Nowadays, Natural fibers are been used to substitute the synthetic ones. Although PALF fiber is an important natural fiber and its mechanical Properties surpass in various aspects some other lignocelluloses fibers, such few studies have been conducted with the fiber obtained from leaf of PALF plant. In order to better evaluate the mechanical properties and possible applications, this paper aims to improve the elastic modulus of the PALF fiber by Weibull statistics, by evaluating their mechanicals properties and possible applications. The fibers were divided in diameter intervals and the tensile strength and elasticity modulus were measured in each range. The fractured surface was examined using scanning electron microscopy. The results, interpreted by the Weibull statistical method, showed a correlation between the fiber elastic modulus and its diameter.

Jan 1, 2015

By Jerrold J. Marcus

United states reserves of oil and gas have been steadily declining while consumption of petroleum products has continued to increase. The nut result has been an ever increasing shortfall between supply and demand. This imbalance has been made up by imports of both oil and gas causing a strain on the United States Balance of Payments. To complicate the situation further, exporting nations have recently formed a cartel and dramatically increased the selling price of petroleum products. To meet U.S. energy demand, increased attention has been drawn to the production of synthetic oil and gas from coal. To date, considerable research has been conducted and is continuing on various processes for liquefaction and gasification of coal. Some of these processes are now in the pilot plant stage and at least one demonstration plant has been proposed. The coal conversion complexes envisioned will be very large, requiring substantial capital investments and abundant reserves of coal. Coal production to feed these proposed complexes has been estimated on the order of 75,000 tons per day. With the viability of these projects becoming economically attractive, the Office of Coal Research initiated a contract with Fluor Utah to determine and define the problems of surface mining coal at very high mining rates, under varied physical, geographic, and climatic conditions. The flow of recent events in the Middle East has created a greater sense of urgency for this study.

Jan 1, 1975

By ROBERT R. RICHARDS

My. first paper, read at the Cobalt Meeting of the Institute,1 July, 1907, dealt with the behavior of a small Wilfley table when concentrating galena from quartz, the table being fed with natural products, with sized products; and with classified products. Since galena, having a specific gravity of 7.5, is among the heaviest minerals ordinarily concentrated by Wilfley table, it was desirable that a similar set of tests upon a mineral of, lighter weight should be made. Chalcopyrite, of a specific gravity of 4, would have been the best mineral for this purpose, on account of its great importance as an economic mineral, but in carrying out the test, however, I was obliged to content myself with a cupriferous pyrite, the specific gravity of which was 4.68 and the contents in copper 8.80 per cent. Through the kindness of Mr. H. 0. Cummins, this material was obtained from Shasta, Cal.,in very pure, clean, homogeneous condition. It was broken by rolls to 2 mm. in size, taking care to make a minimum of slimes. The quartz used to mix with it was pure, white, New England quartz, broken in the same way to the same size. In studying the accompanying tables, it should be borne in mind that the material concentrated was of low copper-content, and in many cases the quantity fed to the machine was 1 kg: or less.. As a consequence of the smallness of the 'quantity treated it was very difficult to adjust the table and get it in condition to do its best work before the feed became exhausted, and for this reason many results were obtained which appear irregular.

Sep 1, 1908

By R. A. Beall

This bulletin reviews the historical background of the cold-mold arc-melting technology, with specific references to the development that led to homogeneous zirconium ingots. Descriptions are given of modern production arc-furnaces for vacuum melting of troth exotic and conventional metals. Besides zirconium, specific data are given for production of chromium, thorium, and copper. The development of the skull-casting technique for titanium is detailed, and the application of the technique to such refractory metals as molybdenum and tungsten is described. Factors of operation of the apparatus and furnace design are considered.

Jan 1, 1968

By D. C. Lynch

While a sizable amount of data exist as to the activity and distribution of minor elements between matte and metal, there has been no unifying theory presented delineating the form of dissolution of these elements in molten sulfides. In order to alleviate that deficiency the literature concerning the behavior of As, Sb, Bi and Pb in mattes is reviewed. Models present in the literature, regarding the thermochemical behavior of minor elements, are tested, and new models are presented and evaluated using thermodynamic theory. The results of those analyses are used to predict optimum conditions for the volatilization of minor elements. The dearth of data on the behavior of minor elements in nickel mattes requires that this review focus on copper- iron mattes. An effort is made, however, to utilize basic knowledge regarding nickel sulfides and the interaction of nickel with the minor elements to predict the behavior of those elements in nickel-copper and nickel-iron mattes.

Jan 1, 1993

By A. -M. Lafront

The corrosion resistance of die-cast and freely-solidified and electromagnetically-stirred thixocast AZ91D alloy has been studied using electrochemical noise technique in a 0.05M NaCI solution at pH 6.1 and 25°C. Specimens polished at different depths were immersed for a period of 75 min in order to assess the influence of the microstructure on corrosion kinetics and morphology. At depths between 10 and 50 µm (skin), all specimens showed general non-uniform corrosion with the lowest corrosion resistance. Between 100 and 200 µmn (interior skin), the observed corrosion was accompanied by superficial undefined pits due to metastable pitting. The corrosion form for 100-200 µm gave the best corrosion resistance. Stable pitting corrosion was observed beyond 400 µm deep on the bulk specimens. The skin of all thixocast specimens prepared billets showed a more corroded surface than that of die-cast. The interior skin as well as the bulk specimens showed better performance than that of the die-cast specimens.

Jan 1, 2007

By H. P. Kritzinger, T. C. Kingsley

Rotary kilns are used for a variety of mineral processing operations. Hatch makes use of a kiln model developed from first principles to evaluate designs for its clients. This tool has been applied to a variety of pyrometallurgical applications. This paper illustrates the application of numerical optimization techniques in combination with the kiln model in the interrogation of a generic iron-ore reduction process. The fundamental modelling concepts are explained, followed by a description of the optimization approach. The results show how the combination of the two methods, with modern computing power, can generate a large number of viable design and operating candidates.

Jan 1, 2014

By Jonathan G. Price

The 2011 report titled ?Energy Critical Elements: Securing Materials for Emerging Technologies? by the American Physical Society?s Panel on Public Affairs and the Materials Research Society surveys potential constraints on the availability of these elements and identifies five specific areas of potential action by the United States to ensure their availability: 1) federal agency coordination; 2) information collection, analysis and dissemination; 3) research, development and workforce enhancement; 4) efficient use of materials and 5) market interventions. Energy-critical elements (ECEs) are a class of chemical elements that currently are critical to one or more new energy-related technologies. A shortage of these elements would significantly inhibit large-scale deployment, which could otherwise be capable of transforming the way in which energy is produced, transmitted, stored or conserved. The report addresses elements that have not been widely extracted, traded or used in the past, and therefore are not the focus of well-established and relatively stable markets (such as carbon in coal or uranium as fuels, copper, aluminum, nickel and iron, all of which are clearly vital in energy applications).

Jan 1, 2011

By Everett H. Dobbs

The Tripoli deposits in the southwest corner of Missouri In Newton County and the northeast corner of Oklahoma in Ottawa County, located in the vicinity of Seneca, Missouri, contains an unusual and peculiar form of silica which has not been found any other place in the world. Its outstanding characteristic is the physical structure of the individual particle, The particle structure of the Missouri-Oklahoma type Tripoli accounts for its market. It is a soft, friable, porous, double-refracting silica of the chalcedony variety, The particle is porous, has a fibrous structure, no sharp edges or comers, ad an average size of less than .01 millimeter, It varies from 90 to 98 per cent Si02 with less than 1 per cent free silica in the form of quartz, 24; has ignition loss of 1 per cent and fractional percentages of iron, alumina, lime, etc.

Jan 1, 1960

By Wei-feng Liu

On the basis of the brief introduction of the gold-antimony concentrate smelting process in China, some problems in the original process were analyzed and the corresponding improvements were introduced in this paper, such as the treatment of antimony matte, the refinement of gold-silver alloy, the concentrating gold from gold-antimony alloy, the treatment of soda slag. The roasting method that was used to treat the antimony matte was transferred to the ore dressing method. The solvent extraction was used to refine the gold-silver alloy instead of the electrolytic method. The technology of selective chlorination leaching under controlling potential was applied to concentrate gold from the gold-antimony alloy and gold-lead alloy instead of the electrolysis method. Soda slag was recovered by the second reducing smelting method substituting for the mixed-salt method of sodium arsenate. After those improvements, the process has been done smoothly; the direct recovery rate of metals has been greatly increased. Meanwhile the procedure

Jan 1, 2008