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By F. E. Harris

The United States produces about 30 percent of the world output of salt. Numerous deposits occur in widely separated areas, but the leading producing States are California, Kansas, Louisiana, Michigan, New York, Ohio, Texas, Utah, and West Virginia. Although no great amount of salt is produced at present in Pennsylvania, the potential sources in that State recently aroused a good deal of interest. The United States salt industry is highly organized; it comprises fewer companies than when small crude works with primitive methods and equipment eked out salt for local needs, but concentration of output brought about by modern inventions and methods of production has improved the quality of the produce greatly and accelerated production.

Jan 1, 1939

By D. Govender

In recent years, economies of scale have continued to drive copper projects to larger throughputs to offset depleting lower grade resources. A decade ago, there were only a small number of projects that stretched beyond 100 kt/d (110,000 stpd) throughput rates. Today, and moving forward, virtually all the major copper projects are sized beyond this, with throughput rates up to 250 kt/d (275,000 stpd) now under evaluation for a number of key projects in Chile and Peru. This paper explores the development from the 160 m3 (5,650 cu ft) flotation cells, through to the 257 m3 (9,076 cu ft) cells and to the current 660 m3 (23,380 cu ft) machines. The contributions of specific copper concentrators to this growth phase are reviewed in this article. The historical basis of flotation machine scale-up is also briefly discussed. Metallurgical results as well as layout, maintenance and operational aspects are highlighted.

Feb 1, 2014

By M. Rufli

Until not so long ago most ring geared mills were operated with fix speed motors only. By using the latest generation of medium voltage frequency converters, new possibilities have arisen to improve the grinding process. Beside all the direct and indirect advantages, several dedicated functions have now been implemented for ring geared grinding mills in the minerals industry. The sophisticated operational functions ensure a smooth, safe and reliable operation with minimum stress for the mechanical equipment and therefore utmost availability of the mill. Several papers have already been presented concerning the benefits of using this state of the art technology for mill drives. Now this paper is focusing on the experiences gained with this kind of sophisticated ring geared mill drive system rather than only show and explains the operational benefit of the different functions. Several measurements of different operating conditions, starting, frozen charge remover, controlled roll back, backlash, etc., made on an installed and commissioned 2 x 5 MW dual pinion ring geared mill drive system will be shown and discussed. The accuracy of the load sharing between the two 5 MW motors during starting, normal operation and stopping will be demonstrated using real measurements from an operating system. Finally the inherent features of these drive systems are briefly discussed.

Jan 1, 2011

By D. Nyembe, B. Mamba, Antoine F. Mulaba-Bafubiandi

Copper and cobalt are generally electro-won from their aqueous sulphate solutions. After optimised leaching of their ores, concentrates or calcine bearing minerals, the leachate is clarified and suitably purified prior to the electrolytic extraction of the metal of pursuit (Pearcy, 2006). Solvent extraction (SX) using appropriate organic solvents and ion exchange (IX) with relevant resins are known purification processes used for copper and cobalt recovery (Stanely, 1970).As zeolites in general and natural zeolites in particular, demonstrate ion exchange properties (Korkuna et al., 2005), an attempt has been made to use Southern African natural clinoptilolite in the recovery of copper and cobalt from their aqueous sulphate solutions. Initially, synthetic Co and Cu solutions were prepared. Preceded by laboratory ore leachate, plant solutions are to be used. AAS, XRF, XRD, Mossbauer spectroscopy and BET were characterization techniques used. Natural clinoptilolite was used as-received as well as acid activated; and cobalt and copper extractions were performed at room temperature.

Jan 1, 2007

By J. P. McCullough

In 1943, the Federal Bureau of Mines began a program of thermodynamic investigations of petroleum constituents and related compounds. These systematic, long-range studies, which were conducted in the thermodynamics laboratory of the Bartlesville Petroleum Research Center and are still continuing, have resulted in a substantial quantity of data valuable to the petroleum industry and science in general. As separate phases of these studies were completed, the findings were promptly reported in the scientific press. During the past 16 years, 89 journal articles, giving the results obtained for individual compounds and small groups of related compounds, were published, mainly in the Journal of the American Chemical Society and the Journal of Physical Chemistry. In addition, members of the Bureau staff have contributed six chapters to specialized reference books. This circular, prepared in response to many requests, lists these 95 published papers, giving an abstract of the contents of each, as well as titles, authors, and literature citations. The journal articles are listed in the order of their preparation, which closely approximates the chronological order of their publication; hence, the item number to the left of each citation corresponds to the assigned contribution number. For the convenience of the reader, the abstract section is followed by a condensed bibliography, arranged alphabetically by senior author and keyed to the abstracts by appropriate contribution numbers in parentheses after the entry.

Jan 1, 1961

Recent and on-going studies on the leaching of gold, the properties and activity of carbon, developments in the elution of gold from carbon, and methods of recovering gold from solution are reviewed. Emphasis is placed on Australian contributions, and their impact on gold metallurgy. Consideration is given to the future development of selective solvent extractants, ion exchange resins or alternative reagents for cyanide.

Jan 1, 1987

By S Bourke, R Stone, B Hill

Since Jameson Cell flotation technology was first installed in a coal flotation application in 1988/89 at Newlands Coal Handling and Preparation Plant (CHPP) there have been fundamental improvements to its design which has led to its current status as the leading technology in Australia for fine coal flotation. These improvements, which include key hardware modifications, consist of the re-development of the orifice plate to produce considerable increase in wear life and reduction in power consumption for a given air entrainment and a significant increase in the amount of air that is entrained. Modifications to the downcomer allow maximisation of residence time and air entrainment while changes to the feed and air distribution system allows a reduction in installation cost and a reduction of solids ingress into the air line. Additionally, operational improvements such as the use of recycle to maintain constant flow to the cell feed are discussed. The recent installation at Hail Creek in the Bowen Basin, which consists of three B6000/20 Jameson Cells (6 m diameter bottom-fed distributor with 20 downcomers) will be reviewed as a case study. The latest design and operability of the cells are summarised and compared against one of the original designs at Riverside CHPP also in the Bowen Basin.

Jan 1, 2005

THE ore treated is almost pure copper pyrites (chalcopyrite) in a gangue of quartz and quartz-felsite. Very little free iron sulphide (pyrite) occurs, and at the time of the erection of the flotation plant the stopes in the oxidized zone had been almostentirely depleted. This zone only extends to a shallow depth, and, below the l00-ft. level, the sulphide for the most part is clean and bright but in the crushed and brecciated parts of the ore channel, where surface water has circulated freely, the gangue is decomposed and kaolinized, and the copper sulphide badly tarnished. This class of ore gave considerable trouble at the mill, but unfortunately, was very limited in quantity. A sample of rich ore assayed-Copper, 21.2 %; iron, 24:.3 %; silica, 28.9 %; sulphur, 25.1%.The concentration in the original mill was effected by handpicking, jigging, and tabling. A considerable portion of the copper mineral arrives at the surface in the form of large lumps of very pure quality, eminently suitable for sorting out by hand.The rich ore is tipped over a grizzly at the shaft bins; the oversize hand-picked, and the undersize bagged direct.

Jan 1, 1912

By Jose R. Hernandez-Aguilar, Chris J. Martin, Rob Thorpe

"This study presents an approach to establishing relationships between metallurgical performance and the characteristics of the bubble population (gas dispersion) inside flotation cells. Bubble size Db, superficial gas velocity Jg, and bubble surface area flux Sb (Sb = 6Jg/Db) measurements were obtained along with metallurgical samples in full-size equipment processing different ore types. The gas dispersion was manipulated by changing the operating conditions of the cells (gas flowrate and frother type) and the metallurgical performance (grade-recovery) was determined. In two cases, the Sb had a strong relationship with grade and recovery, hence, Sb could be used as practical operating parameter. In another case, Sb did not correlate with recovery. The reasons were attributed to creating small bubbles using frothers with desired anti-coalescence properties. This illustrated that bubble size was the key parameter for metallurgy rather than Sb.INTRODUCTIONUnravelling the mechanisms that govern the relationships between metallurgical performance and the characteristics of the bubble population (gas dispersion) inside a flotation cell remains a major challenge. Information on this subject is scarce in the literature, particularly, plant-scale data. The report of Jameson and Allum (1984) appears to be the first gas dispersion study conducted in industrial (mechanical) cells. To introduce concepts, some aspects of their work are reviewed here.The prime motivation of that study was to establish whether any particular cell design (among 44 cells surveyed) could produce very small bubbles (< 0.1 mm), which laboratory research suggested would increase the recovery of fine particles. Although one of the outcomes was that the (examined) cells did not seem to produce such small bubbles (Sauter mean1 D32 ˜ 0.9 mm), the analysis highlighted the importance of including other factors. Jameson and Allum indicated that, besides bubble size (Db), other characteristics of the bubble dispersion should be considered, namely: gas holdup ?g – the fraction of cell volume occupied by bubbles, superficial gas velocity Jg – is the gas flowrate divided by the cross-sectional area of the cell and, bubble surface area flux Sb – the rate of production of (new) bubble surface area (m2/s) per m2 of cell cross-sectional area. It should be noted that, whereas Jg, ?g and Db can be measured directly, the Sb is derived: Sb = 6Jg/Db, where Db is usually substituted by the Sauter mean diameter (D32)."

Jan 1, 2006

By Gustavo Quiquia Mucha

El presente texto describe las experiencias realizadas por la Compañía Minera Milpo SAA en el marco de una gestión social basada en la consulta previa, libre e informada en la Exploración Minera Responsable. En ese sentido, es importante la cooperación entre la empresa minera y la comunidad, así como la incorporación del marco ideológico empresarial y metodológico, basado en los principios del Convenio 169 de la OIT sobre Pueblos Indígenas y Tribales en Países Independientes, las estrategias y las líneas de intervención social de la Compañía Minera Milpo SAA en los proyectos de exploración minera responsable.

Sep 12, 2011

By P. A. Plunkert, D. E. Morse, Pui-Kwan Tse, W. D. Menzie, Lucy McCartan, J. F. Papp

China’s burgeoning economy is responsible for a major share of recent world mineral consumption increases. In addition to factors traditionally recognized in market economies1 and factors unique to specific commodities, Chinese consumption now plays a major and increasingly important role in energy and mineral markets for many commodities, such as aluminum, copper, iron and steel, and oil. China has the world’s second largest economy after the United States. And its long-term importance to the minerals markets is even greater than indicated by its gross domestic product (GDP), which is currently less than two-thirds of that of the United States (Table 1). This is because China’s rising standard of living is accompanied by rapid industrialization and urbanization. Its consumption of mineral materials for infrastructure development for its very large population is significantly greater per capita than that of such developed economies as the United States, the European Union and Japan. In other words, China’s per capita production is rising at a rapid rate and will probably continue to do so for many years.

Jan 1, 2006

By Diler Katircioglu-Bayel, Oner Yusuf Toraman, Safak Gokhan Ozkan

One of the most energy-intensive processes for producing submicron range calcite is stirred media mill. In the present work, numerous operating parameters such as solid mass fraction, grinding media size, media filling ratio, and grinding time have been investigated using a vertical type stirred media mill. The results are evaluated on the basis of mean particle size, specific surface area, and specific energy consumption. After conducting this study, optimum experimental conditions found to be as 70% media filling ratio, 25% solid mass fraction, 1 mm grinding media size, and 120 min grinding time. Besides, energy savings up to 22% were achieved with the choice of proper media size.

By Jaime Tumialán

El presente artículo describe los trabajos subterráneos de la mina Cobriza, la mina más mecanizada del Perú, dado que es la primera en aplicar el minado sin rieles con equipo pesado montado sobre llantas neumáticas u orugas. La mina se encuentra localizada en la Oroya, Huancavelica. Las razones de su mecanización son: crecimiento de los costos, avance de la tecnología, la forma, magnitud y potencia del manto, así como la dureza y resistencia del mineral. Su método de minado es "Corte y Relleno altamente mecanizado con equipo pesado y tiene una productividad en subsuelo de 20Tn/h-g.

Nov 1, 1972

By W. B. Tarpley

This program was conducted to demonstrate the unique advantages of suppressing methane ignition in underground mines by use of Energy & Minerals Research Company&apos;s thixogel fire extinguishing system, which stably suspends dry powder extinguishing agent in thixotropically gelled liquefied gas extinguishant. As anticipated, the project demonstrated thixogel system advantages of: 1) capability to disperse state-of-the-art powders in thixogelled Halons; 2) non-agglomerating stability for dependable expulsion; 3) stability in storage for long shelf life; 4) virtually in¬stantaneous dispersion; 5) expansive cloud formation; 6) reach and re-forming around obstacles; 7) at least twice the extinguishant effectiveness; and 8) compatibility of use with Fenwal bottles and MSHA canisters. Thus, it should prove a superior explosion/fire suppressant for coal face cutters and triggered barriers, as well as for motorized equipment, electrical equipment and the like.

Jan 1, 1981

By J. William Ganser

This paper is one of a series being prepared by the U. S. Bureau of Mines describing mining and milling methods and costs at cement-plant quarries throughout the United States. These papers are designed to disseminate technical information regarding the methods used. The cost tabulations represent local operating expenditures only and not total production costs. It is recognized that publication of total production costs might in many instances cause embarrassment to individual producers as well as to the industry as a whole. On the other hand, operating costs are essential to the technical discussion and study of the methods employed. The attention of the reader is specifically palled to this differentiation in order that no misunderstanding of the scope of the cost tabulations shall ensue. ACKNOWLEDGMENTS The author wishes to acknowledge the assistance of Fred Burkett, civil engineer, and F. O. Londrey, chief clerk, of the Trinity Portland Cement Co., for assistance in preparation of this paper, "The Geology of Dallas County. 1918," Bulletin 1818, Texas Geological Survey, Austin, Tex., by E. W. Shuler, was also freely consulted.

Jan 1, 1931

By F. C. Noyes

DAME Nature was in a generous mood when she distributed widely over the face of the globe numerous deposits of phosphate rock from which man can make phosphatic festiIizer to replace the phosphate re- moved from the soil by crops. The principal deposits are readily accessible to the world&apos;s greatest consuming areas and most of them are such that mining operations can be carried on at relatively low cost. The world&apos;s known reserves shown in Table 1 are sufficient to last well over 2000 gears at the present rate of consumption. Before giving a brief outline of the phosphate rock industry of foreign countries let us try to get a picture of the movement of phosphate rock throughout the world in 1938, the last full normal calendar year where it came from and where it was consumed. Table 2 shows the origin and finial destination of world shipments in 1938 by grand divisions. Table 3 (p. 499) shows shipment9 of phosphte rock to each country in Europe. Europe is seen to be by far the world&apos;s greatest market and the French North African mines the world&apos;s most important producers outside of the U. S. A.

Jan 1, 1944

By J. A. Taylor, H. F. Yancey

"INTRODUCTION Froth flotation as applied to coal is a process for separating desirable carbonaceous material from undesirable inorganic matter. In general, the feed must be finer than one eighth inch in size. The principal use of the process in the preparation of coal appears to be in the treatment of the fine sizes produced by breakage during mining and preparation.The Bureau of Vines in Information Circular 6714 has published general information on coal flotation, summarized investigative studies of the process, and described operating plants throughout the world with their tonnage, reagent consumption and operating costs.4ACKNOWLEDGMENTSThe present study of means for depressing pyrite and reducing ash ty froth flotation was conducted at the Northwest Experiment Station of the United States Bureau of Wines in cooperation with the College of vines. University of Washington, under the general direction of A. C. Fieldner, chief engineer, Experiment Stations Division, Bureau of Wines. Grateful acknowledgment is made for suggestions and criticisms received from W. H. Coghill, supervising engineer, U.S. Bureau of Mines Mississippi Valley Experiment Station, Rolla, Mo.; J. B. Morrow, and R. E. Zimmerman, of the Pittsburgh Coal Co.; and Dean Milnor Roberts and Prof. Joseph Daniels, of the College of Mines, University of Washington.FLOTATION AND DEPRESSIONA substance will tend to float if its surface attracts a gas film more strongly than it does a liquid film when both air and liquid are competing for this attraction. On the other hand, a substance will not float if its surface attracts a liquid film more strongly than it does a gas film. All theories of depression depend upon this fact. A wetted particle of floatable size most likely will be found in the tailings after the flotation process has been completed.The crux of flotation is the selective wetting of the undesirable material that tends to float. Two general methods 5, 6, 7 of depression are in use: One combines a chemical substance with the surface to form a wettable compound, and the other employs some colloidal or ionic substance which the surface selectively adsorbs, thereby forming a wettable surface."

Jan 1, 1935

By Mills R, Shannon W. T, Finch J

As an extension to investigations into methods of upgrading the Iitania content of ilmenite concentrate from beach sands using 100 g/day, a small pilot plant treating 23 kg/ day of ilmenite was used.In the pilot plant the iron oxide in the ilmenite was reduced to iron at 1200&#176;C using carbon (coal/char) without melting the material, using a tunnel kiln heating cycle, the charges contained in saggars, The iron was then separated from the titania fraction by ball milling, wet magnetic separation, and screening. The resulting magnetic product was high in iron (about 80 per cent Fe) and the non-magnetic product high intitania (about 70 per cent TiO2).From this trial sufficient data were obtained to enable the preparation of a flow sheet for a plant producing 62,300 tonnes/year total products, and an estimate of costs to be made. This has shown that for an estimatedcapital expenditure of nearly $6,000,000 and annual production costs of about $4,000,000, the cost per tonne of high titania product (76 per cent TiO2) would be nearly $70.

Jan 1, 1977

By Bodo Peinemann

For more than 35 years Lurgi has been providing its fluid bed roasters on a world­wide basis. The current total annual capaci­ty of the 250 Lurgi roasters approaches 26 million mt of sulphide minerals, including gold-bearing flotation pyrite concentrates. While the stationary fluid bed has been uti­lized for roasting exclusively, Lurgi has now commercially introduced its Circulating Fluid Bed (CFB) technology for gold roasting in a successful effort to maximize gold re­covery.

Jan 1, 1990

Organization Place Date 1919 American Electrochemical Society New York, N. Y. Apr. 3-5 American Chemical Society Buffalo, N. Y. Apr. 8-11 National Foreign Trade Council : Chicago, Ill. Apr. 24-26 American Iron and Steel Institute New York, N. Y: May American Institute of Electrical Engineers Lake Placid, N. Y. June 23-27 American Society for Testing Materials..: Atlantic City, N. J. June 24-27 American Railway Bridge and Building Association Cleveland, O. Oct. 21-23

Jan 4, 1919