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A very sensitive high-speed two-colour pyrometer was built to measure the temperature of single particles of sulphide mineral, typi- cally 50 pm in diameter, as they burnt while entrained in a hot gas stream. The pyrometer has been used to study the burning of pyrite and chalcopyrite particles and has thrown light on cenosphere formation. Measured maxi- mum temperatures have been compared with values predicted by diffusion-based models. The pyrometer has also been used to study the burning of small captive pellets (2-9 mmm dia- meter) of lead-zinc concentrate.

Jan 1, 1984

By Jay Smerekanicz, Florin: Pedersen Gheorghiu, Alan Cameron

In order to expand the capacity of Modern Landtill, a groundwater extraction system consisting of a linear system of pumping wells over 2,700 feet long had to be replaced. The new system would be covered by landtill cells to a depth of approximately 400 feet, and therefore would have to be maintenance free. In addition, the new system had to be proven to be more effective than the previous system, groundwater extraction had to be maintained during construction and construction could not disturb either the landfill operation or nearby residential neighbors.

Jan 1, 2001

By Heinrich A. Kortmann

Specifications on the chemical, physical and metallurgical properties of the blast furnace burden are steadily becoming more stringent, especially in those countries where higher raw material and energy costs can be overcome only by improved technology. This paper describes the test methods for the relative predetermination of the criteria where the effects of temperature, gas composition and physical load in the blast furnace are duly considered. Data are presented to show the correlations between burden material tests and blast furnace results. Possible test methods for the direct reduction process are also discussed.

Jan 1, 1977

The coal basins that formed near the margin of Permian Australia were comparable in size with the Appalachian coalfields and with the European fields between Wales and Poland. They formed on the foreland side of a growing orogen in a system of linked transform basins formed by transtension on strike-slip faults. They were terminated and compressed when the Gympie volcanic arc was accreted to the orogen. Another huge system of Permian coal basins extending far inland from the Permian coast was also terminated when the Gympie Terrane was Accreted.

Jan 1, 1987

Sampling and analysis of mineral deposits need to be executed without fear or favour of financial or personal impacts. Examples are given to illustrate the effects of departures, witting and unwitting, from correct use of appropriate techniques and/or equipment with emphasis on exploration and mining of porphyry copper deposits of the Pacific Rim. Some of the results of errors on the low and high sides of true value in exploration, resource or reserve estimations and in production caused by sampling and/or sample preparation mistakes, faulty practices, equipment and/or analysis are considered.

Jan 1, 2004

By Arthur L. Bishop

INTRODUCTION Purpose The in-situ leach method for uranium extraction is a relatively new and innovative method of uranium mining. In 1975, the first commercial in-situ facility began operation in south Texas. Since that time numerous other operations have been initiated as either pilot or commercial ventures. Considerable literature has been published that deals primarily with generalities of the process or environmental concerns. Several federal agencies have published documents which do not reflect the true operating or environmental nature of the in-situ leach method of uranium extraction. From an environmental standpoint, this is also evident in the promulgation of rules and regulations. Hence, the purpose of this paper is to present experience with an environmental concern--non- production zone excursions--such that the industry and the regulatory agencies will gain greater insight devoid of preconceived ideas and misconceptions. General Process Description In south Texas, in-situ leach mining is utilized to extract uranium from permeable sandstone ore deposits 61 to 213 meters (200 to 700 feet) below the surface. Uranium is present as an insoluble uranium oxide. In the in-situ or solution mining technique, anoxidizing lixiviant is injected into the formation through injection wells. The solution reacts with the insol uble carbonate complex. This soluble uranium complex is produced at recovery wells, each containing a submersible pump. During production there is a constant sweeping of lixiviant through the formation from the injection wells to the recovery wells. Injection and recovery wells can be arranged in any of a number of geometric patterns dependent upon ore body configuration, aquifer permeability, and operator preference. Submersible pumps in the recovery wells pump the uranium rich pregnant solution to the initial processing facility. Monitor wells surrcsund the pattern area and are screened in appropriate stratigraphic horizons (production and non-production zones) to detect any lixiviant migration that may occur (Fig. 1).

Jan 1, 1980

Previous studies on the blast furnace raceway zone have been undertaken at three levels of scale, namely: laboratory models at low temperature, hot models which simulate coke combustion in the zone, and tests performed on operating and dismantled blast furnaces. This paper reviews the results of this published work on raceways in order to illustrate the factors which affect the raceway shape, size and combustion characteristics. As a result of the work it has been established that raceways are influenced by blast parameters such as velocity, temperature and chemistry, as well

Jan 1, 1981

By X. P. Zheng, H. K. Lin

During slow-cooling crystallization of iron-making blast furnace slags, most rare earth elements recrystallize in an artificial "mineral" identified as calcium cerite. Scandium (Sc) and europium (Eu), however, concentrate in a sheetlike "mineral." In this investigation, the mineralogy of this sheetlike "mineral" was studied. It was identified as being in the mica group and was called a rare earth-bearing barium fluorophlogopite. One of the objectives of this study was the recovery of this "mineral." The study indicated that it can be effectively recovered from the slag by flotation using dodecylammonium acetate or a combination of dodecyl-ammonium acetate and sodium oleate as collectors.

Jan 1, 1998

By Ted H. Eyde, Dan T. Eyde

Industrial minerals deposits present sampling and grade control problems not normally encountered in metal mining operations. No longer are industrial minerals simply crude ground mineral products but are in fact high purity chemical raw materials. Operators of industrial minerals mines and processing plants now must meet increasingly stringent specifications established by the consumer of the final products. Meeting these stringent specifications requires not only sophisticated processing techniques but equally important careful sampling and grade or quality control at the mine. A well-trained geological staff can assure an adequate supply of uniformily high quality feed to the processing plant. In the final analysis this results in significantly higher operating profits.

Jan 1, 1985

By P. C. Kapur

A principal first-order and a minor summation term contribute to the solution to the discretized batch-grinding equation when formulated in cumulative retained mode. Depending on the inter relations hips between the selection and breakage parameters, the minor term may be advantageously modified in a number of ways. The reduced grinding equations thus obtained are solved by iterations to give relatively simple solutions which are tested against experimental data. The irn-plications and advantages of the reduced grinding equations are briefly discussed. In many instances, the trajectory of the particle-size distribution in a batch mill may be extracted from a set of particle mass balance equations as follows

Jan 1, 1971

Edwin Ludlow, the forty-first President of the A. I. M. E., died in Muskogee, Okla., on Feb. 10, 1924, after a brief illness of influenza followed by pneumonia. He was born in Oakdale, N. Y. (on Long Island), March 12, 1858, a son of William Handy and Louise (Nicoll) Ludlow. He attended Flushing (L. I.) Institute 1868-75, and Columbia School of Mines (N. Y.) where he was graduated with the degree of Engineer of Mines with the Class of 1879. After graduation, his first employment was as assistant engineer in river and harbor work on the Delaware River near Philadelphia. In 1913

Jan 1, 1924

By M. Specht, D. Pörzgen, W. Lorenz, A. /. Buhr, R. P. Racher

The introduction of the near net-shape casting process at CORUS Staal IJmuiden in January 2000 required changes of secondary metallurgy processes including a development towards more aggressive slag compositions in the steel ladle. Therefore the steel ladle lining has been changed from fired andalusite bricks to magnesia-carbon bricks and, most recently, to fired spinel bricks to withstand the severe slag conditions. In comparison to the andalusite bricks the new steel ladle linings have a higher thermal conductivity. This requires the capability to keep the lining warm by ladle preheaters to sustain the overall thermal stability of the steel ladle in case of interruptions during hot cycling of the ladles.

Jan 1, 2004

By Thomas L. Barkley, Michael A. Indihar

The new Cyprus Northshore Mining Co. has taken the previous blasting methods of Reserve Mining Co.'s mine in northern Minnesota and adapted them to a new competative Iron Ore Industry. Cyprus was challenged to develop new blasting methods to reduce costs and improve results over the previous mining operation. Many of the older procedures have been kept, but others have been changed in ways that bring the mine operation up to state of the art technology. In addition, unique ideas not previously tried in the North American Iron Ore Industry have been instituted. So far, this has reduced Cyprus's blasting costs by 70 percent.

Jan 1, 1991

Background: The National Institute for Occupational Safety and Health (NIOSH) recently investigated ignition incidents resulting from drilling holes into sealed and filled plow frame sections. A farmer and farm worker were seriously burned in two separate incidents that occurred in the same county in New York under similar conditions. They had just penetrated sealed sections of their plow frames with electric drills when a roar of escaping gas at high pressure was heard, and the victims were thrown back by the gas jet and engulfed in flames. The flames were quickly extinguished ,but the victims suffered burns. NIOSH experts were asked to help find the cause of these hazardous incidents.

Jun 1, 1998

Until the early 1960s the world aluminium industry was dominated by six principle pro- ducers with integrated activities from bauxite mining to aluminium production. The growth in consumption of aluminium since that time and the emergence of additional producers has broadened the market for bauxite. In addition the increase in the optimum size of alumina refin- eries has influenced competing metal producers to unite in large joint ventures to minimize alumina costs. From these bases the paper examines present and likely future markets for Australian bauxite; differing marketing phil- osophies for serving those markets; factors influencing successful marketing; and the sources and relative strength of competition which Australia faces.

Jan 1, 1974

The suggestions of the members of the Institute are very much desired by the Committee on Nominations prior to deciding upon its nominations to fill the places of those officers who retire early in 1917. The Committee must make its final report to the Board of Directors early in October. The members are, therefore, asked to send in promptly their .suggestions for Directors as well as for Vice-Presidents and President. The Committee hopes to hear from a large number of the members. The officers to be elected at the annual meeting in February, 1917, are: One officer, known as Director and President. Two officers, known as Director and Vice-President

Jan 8, 1916

By C. W. Merrill

Minerals research by the U.S. Bureau of Mines embraces the mining and metallurgical problems of some 80 metals and nonmetals excluding the mineral fuels. It requires the energies and talents of about 1400 persons, almost half of whom are professionally trained in the physical sciences or engineering. Of approximately $13 million appropriated to the Bureau for minerals programs in Fiscal Year 1962, 76% has been allotted to technologic research and 24% to resources examination and appraisal. In addition, almost $2 million will be made available to the Bureau for minerals research from other Government sources and from private organizations that wish to utilize Bureau experience and capabilities in cooperative studies.

Jan 11, 1961

By R. A. Metz, Ted H. Eyde, Dan T. Eyde

Industrial minerals deposits present sampling and grade control problems not normally encountered in metal mining operations. No longer are industrial minerals simply crude ground mineral products but are in fact high purity chemical raw materials. Operators of industrial minerals mines and processing plants now must meet increasingly stringent specifications established by the consumer of the final products. Meeting these stringent specifications requires not only sophisticated processing techniques but equally important careful sampling and grade or quality control at the mine. A well-trained geological staff can assure an adequate supply of uniformily high quality feed to the processing plant. In the final analysis this results in significantly higher operating profits.

Jan 1, 1992

Terminology Relating to Nonmetallic Elements in Metals. See IRON AND STEEL Ferromagnetism in Metallic Crystals. BY L W MCKEEHAN (Tech. Pub 554, Metals Tech , August; also Trans, vol 111. 20,500 words ) The directions for easiest magnetization of ferromagnetic single crystals are those of simple crystal- lographic forms and the extra energy needed for magnetization in other than these preferred directions depends upon the material selected for test The history of magnetic tests upon metallic single crystals, reviewed in detail, shows that crystals of one metal agree rather well as to the magnitude of such energy differences. This makes ~t probable that these differences are really charactenstic of the ferromagnetic

Jan 1, 1935

By M. R. Nelson

Continuing experience in the Black Hills, South Dakota, indicates the persistence of several natural contaminants in mine waste effluents under circumneutral pH conditions. Selenium and arsenic are the most problematic environmental contaminants observed in these effluents. The contaminants are present in ore and waste rock as naturally occurring trace elements, and under the physico chemical conditions of the mine waste repositories are mobilized by oxidation and desorption reactions into infiltrating water. Characteristics of the mine wastes, waste repository construction, and Black Hills climatic conditions, indicate these natural contaminants may persist well into the future causing long-term mine closure liabilities, a difficult challenge to both mine operators and regulators.

Jan 1, 2003