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By J. B. Shannon, J. D. Grenia

The Buick Mine is a joint venture of American Metals Climax, Inc. and Homestake Mining Company located 120 miles by road southwest of St. Louis, near the village of Boss, in the `New Missouri Lead Belt'. Since start-up in 1969, over four million tons of lead-zinc ore have been mined and milled at Buick. Situated 1100 ft below the surface at an elevation 270 ft above sea level, the flat lying sinuous orebodies are up to 250 ft wide, 85 ft high and several thousand feet long. Mineralization is galena, sphalerite and chalcopyrite in dolomite.

Jan 7, 1973

By Robert M. Abrams

The passage of an ore pulp through the froth flotation process results in the production, after dewatering, of a finely divided concentrate. This intermediate product must be handled to the subsequent process facilities via beit or other types of conveyors, hoppers, bins, chutes and feeders, and the like. Flotation concentrate has some difficult handling properties such as abrasiveness, sluggishness when moist, or fluidity when dry. These characteristics require the judicious selection or design of handling equipment and the careful engineering of transfer chutes. It is to the special problems which are encountered in this in-plant handling procedure that this paper is addressed. The methods which will be discussed have been developed primarily for the handling of the froth flotation concentrates of copper, lead, and taconite iron ores, but may be generalized, with appropriate modifications, to apply to other similar metallic concentrates. The controlled feeding of concentrates from bins and hoppers is covered along with some of the techniques used to transfer concentrates from one belt conveyor to another. Methods are described for unloading belt conveyors into bins or storage piles. The reclamation from storage piles is also treated.

Jan 1, 1979

By Cyril Stanley Smith

BeTa brass (consisting of approximately equal atomic proportions of copper and zinc) exists as a random solid solution at high temperatures, hut at low temperature< an ordered structure is stable, with the copper and zinc atoms occupying alternate sites on the body-centered-cubic lattice. On cooling, ordering commences at a temperature of 450° to 470°C., depending on the composition. The degree of ordering progressively increases at lower temperatures until it becomes virtually complete at about 100°C. The electrical resistivity of the alloy illustrates the changes clearly (Fig. I). This type of reaction has been a favored subject for study by physicists. An excellent summary of the theory is to be found in a paper by F. C. Nix and W. Shock1ey.l All published data on electrical conductivity, specific heat and other properties agree in indicating that the ordering reaction in beta brass takes place so rapidly that it cannot be prevented or even retarded by quenching&apos; With most ordered alloys, cold-working induces disorder and

Jan 1, 1943

By E-Tu Zen Sun

Yunnan, a mountainous province in southwestern China, began to assume its place as an important producer of copper toward the end of the Ming dynasty (latter part of the 16th century), and since then has continued, with minor interruptions, to occupy a leading position as one of the few areas in China where relatively significant amounts of this metal can be produced. Among the copper deposits of this province, those of the following three localities have stood out as being the most significant. 1. Tung-ch&apos;uan, in northeastern Yunnan. Here the ores are primarily bornite and chalcocite, with copper content ranging from 2% to 15% the most noteworthy T&apos;ang-tan mine producing ores averaging 12% copper. Estimated total reserve of pure copper in this area is approximately 1,000,000 metric tons.

Jan 7, 1964

The Institute conducts jointly with the American Society of Civil Engineers, American Society of Mechanical Engineers and American Institute of Electrical Engineers, certain activities as listed below, and is joint owner with them of certain properties situated at 29 West 39th Street in New York City United Engineering Trustees, Inc. When Mr Carnegie made his gift, "for the erection of a suitable union home" for the engineering societies, United Engineering Trustees, Inc (then United Engineering Society) was chartered un¬der Chapter 703, Laws of the State of New York, 1904, for "the advancement of the engineering arts and sciences in all their branches, and to maintain a free public engineering library " The Corporation was further empowered to acquire real and personal property and to use, maintain and occupy it, with the provision that any building erected by the Corporation shall be used perpet¬ually as a meeting place and headquar¬ters for the Founder Societies Thus the Carnegie gift realized the ideal of bring¬ing the engineering societies together under one roof, and the Corporation through its members nominated in equal numbers by the four Founder Societies had the necessary authority to act for the Founder Societies in their joint in¬terests in owning and operating for them not only Engineering Societies Building, but in the course of time, Engineering Societies Library, and The Engineering

Jan 1, 1952

By R. H. King

The Automatic Extraction System (AES) was designed and built under a US Department of Energy Contract by the National Mine Service Co. in cooperation with the Lee Engineering Division of Consolidation Coal Co. The Pennsylvania State University, Mining Engineering Section, was contracted as an independent auditor of the AES performance. The AES had a rotating cutter drum like a continuous mining machine. But two hydraulically powered roof supports, four roof-bolting drills, a dust scrubber, a ventilation fan and ducting in the roof supports, semi-automatic control, an extensible chain conveyor, and other innovations led to the distinction "extraction system" as opposed to "miner-bolter" or continuous mining" machine. After design and assembly, the AES was field tested experimentally in an underground coal mine. The in-mine performance audit was preceded by a computer simulation of the potential production for a later comparison with the actual tonnage mined by the AES. This paper describes the results of an in-mine trial and assesses the production potential of the AES.

Jan 1, 1983

By J. H. Allen

The air lift method of pumping water is discussed. A review of several large diameter hole drilling projects that used reverse- circulation air-lift techniques is presented. Proposals are made for reverse circulation flow rates for slow rates of bit penetration (5 fph) as well as reverse-circulation flow rates for faster rates of bit penetration (10 fph). The Ingersoll-Rand air lift equations are modified for rotary drilling operations. By establishing minimum reverse circulation flow rates and utilizing the modified air lift equations, the establishment of minimum circulation equipment sizes and a more definitive requirement for improved bit body design should result.

Jan 1, 1978

By Garland R. Dever, Preston McGrain, George W. Ellsworth

Limestone resources for industrial, constructional, and agricultural uses occur on the surface and at minable depths in several areas along the Ohio River and its navigable tributaries in Kentucky. High calcium and high carbonate limestones suitable for use in cement and lime production, steel manufacture, environmental control measures, and other special uses are present in the High Bridge Group (Ordovician) and Warsaw and Ste. Genevieve Limestones (Mississippian). Deposits with thicknesses of 7.3 to 20.7 m,(24 to 68 feet) have been documented by the analysis of samples taken at 0.3-m (1ft) intervals. Active and potential mine and quarry sites afford access to water transporation and proximity to a number of industrial and metropolitan centers. Geologic factors affecting the distribution of deposits include the Cincinnati arch, regional dip into the Appalachian and Eastern Interior basins, complex faulting in and near the western Kentucky fluorspar mining district, and late Paleozoic erosional unconformities in northeastern Kentucky.

Jan 1, 1979

By K. V. S. Sastry

First attempts to apply computers for the modeling, simulation and analysis of mineral processing unit operations date back to almost twenty years. Since then substantial efforts have been directed to the development of computer software for mineral processing. Current literature indicates considerable activities in the development of computer packages for interactive and batch simulation of individual unit operations and integrated plant operations. This paper presents a comprehensive review of various simulation systems that have been described in the literature along with a discussion of present trends in the development of mineral processing simulation software. Finally, the paper includes a detailed discussion of the desirable features in future simulation packages.

Jan 1, 1984

By Walter E. Dean

Deep-sea manganese nodules are considered to be potential ores of manganese, nickel, cobalt, and copper. Considerable time, effort, and funds have been applied to the study of the distribution of nodules on the seafloor and the location of economically important areas, but less effort has been spent in understanding the origin of nodules. Most theories that have been proposed to explain the origin of manganese nodules have been based on inorganic processes. It is not by coincidence, however, that the area considered to be most economically feasible is, in the zone of high biological productivity in the eastern equatorial Pacific Ocean and underlain by siliceous biogenic sediment. The genesis of manganese nodules and the concentration of many trace elements are related indirectly, and possibly directly, to the activities of organisms.

Jan 1, 1983

By Y. Zimmels, I. J. Lin, I. Yaniv

The potential application of magnetic and electric separation techniques in beneficiation of fine-particle feeds are reviewed. Special features of these techniques are considered and compared with a view to increased amenability of such feeds to separation in electro- magnetic fields. The following techniques are discussed, with reference to those already developed and in use to-date: - Differential-susceptibility separation (DSF). - High-gradient differential-dielectric separation (HGDDS). - High-gradient magneto-gravimetric separation (HGMGS). In this context the new approach - whereby selectivity of solid- solid separation processes, in wet high-gradient magnetic and electric separation, can be improved - is described, including experimental results from DSF and HGDDS tests.

Jan 1, 1980

By Carlos D. da Gama, Charles R. Nelson

Griffith’s theory of brittle fracture, as modified by McClintock and Walsh to fit rock behavior in cases of failure by compression, has been successfully applied in various fields of rock mechanics. Extension of the Griffith&apos;s criterion to rock blasting problems may also be more representative of rock behavior than the simple consideration of a criterion of failure based on the dynamic tensile strength of the material. If consideration is given to pre-existing cracks within rock structure, occurring not only because of the discontinuous properties of rocks, but also as a result of drilling operations that normally precede blasting, those cracks can be propagated under the action of the dynamic stresses (radial and tangential) induced by the passage of the wave emitted by the explosion. Conditions for initiation and propagation of pre-existing cracks are deduced in terms of rock properties and explosives performance. Influence of the different variables governing the phenomenon is discussed after considering an actual example. Results seem to be well correlated with experimental evidence of radial cracking observed in blasting with high explosives acting within hard rock.

Jan 1, 1971

By M. P. Board, M. J. Reus

Instrumentation was installed during construction of the Silver Shaft in northern Idaho to evaluate lining behavior and rock deformation. Rock mass displacements were monitored with multiple-position borehole extensometers. Liner stress and strain were measured with concrete pressure cells and embedment strain gages. Rock displacement data from the 5,955-ft level indicate rock mass anisotropy. Liner stress and strain data reflect high in situ stresses and nearby station and raise construction. Continued monitoring and preliminary analysis indicate that concrete-lined, circular shafts are stable for high, unequal stress fields and anisotropy in deep level mines.

Jan 1, 1984

By Ichiro Ito

At present, in Japan, the application of in-place leaching technique to the mined-out stopes has been carried out at two copper mines in a comparatively large scale. These mines are the Kosaka mine and the Tsuchihata mine, both are situated in the north-east district of Japan. At first, the author would like to tell about the in-place leaching operations and their results at these two mines. Then, the problems involved in the application of in-place leaching technique to the Japanese metal mines and the possibility of the future development of this technique in Japan are referred, too. Next, as to the research works, the author would like to explain briefly about some of the important results obtained in the recent studies on in-place leaching as well as on bacterial leaching in Japan.

Jan 1, 1976

By Klaus Schonert

The elements of a mill matrix and the classifier matrix de- scribing the grinding process depend on operating conditions, especially on the feed rate. Relationships between the matrix elements and the feed rate have a great influence on the stability of a closed circuit and its optimum point. These problems have been studied by means of computer simulation and different kinds of classifier characteristics have been considered. A circuit with a cross stream classifier has only a limited range where stable operation condition can be attained. Beyond the stable limit, the recirculation ratio increases rapidly and there is no correlation between feed rate of the circuit and feed rate of the mill. In comparison, a spiral stream classifier gives a wide range of stable operation. The recirculation ratio can be greater than in the case of the cross stream classifier if the feed rate is small. The results of the simulation provide a better understanding of the real behavior of closed circuit grinding.

Jan 1, 1969

MORE than 2500 members of the AIME from all sections of the U. S., Canada, Central and South America are expected to attend the 175th General Meeting scheduled for Los Angeles Feb. 16 to 21, 1953. The Southern California Section will be host for the meeting. It will be the first time the Annual Meeting has been held in Los Angeles. In keeping with the historic nature of the event, headquarters will be the fabulous Statler Hotel, recently opened in downtown Los Angeles. Meeting plans are under the direction of Henry T. Mudd, General Chairman, assisted by members of the Southern California Section, headed by Basil P. Kantzer. The annual business meeting is scheduled to be held Tuesday, February 17, at the Statler Hotel, at 4 pm. Minerals Beneficiation Div. has planned a very important program, with 10 technical sessions, the famous Scotch Breakfast, divisional luncheon, and participation in the Mining Branch and All-Institute activities. The MBD business meeting is set for the morning of Feb. 16, 1953.

Jan 1, 1952

Shoemaker: We&apos;ve all heard a lot about epoxy liner backings. This brings up the question-do zinc furnaces still have a place in a new plant? Meaders: I would, you must understand, be prejudiced in this question because we introduced epoxy backing into the industry. Naturally, we wouldn&apos;t have done so if we didn&apos;t think it should be done. With that background maybe I could give a little more information on this particular subject than some of the others, because we now have been in this business for some three or four years.

Jan 11, 1967

By R. P. Carreker, R. L. Fullman, J. C. Fisher

THE existence of the phase TiAg has not been reported previously. Other investigators have denied the existence of compounds in the Ti-Ag system.13&apos; However, phases of equi-atomic proportion have been reported by Raub, et al.&apos; in the (similar) systems of titanium with gold and copper and zir- conium with silver. Raub&apos;s work indicated that titanium and silver are immiscible in the liquid state. No evidence of this was found although a very wide melting range exists which makes the preparation of homogeneous alloys difficult. TiAg is apparently formed by a peritectic reaction between /3

Jan 1, 1954

By William Reynolds

THIS paper deals with the results of a study of the application and development of mining machines for cutting out and removing dirt bands in bituminous coal beds. FACE PREPARATION When one or more dirt bands1 occur in a seam of coal, the problem of elimination of impurities becomes manifest. The degree of complete-ness to which these impurities are removed at the face has an important bearing upon labor costs, haulage costs and outside cleaning costs, and often the ash content of the product is markedly affected. Yet, because the present-day miner is paid for the number of tons he loads he often lacks interest in the quality of the coal. To insure a clean product, a system of penalties for dirty coal is enforced, but control of extraneous impurity content in the loaded coal is often inadequate and ineffectual when coal and banded impurity are shot as one. It seems only logical that to reduce the amount of impurities by proper face preparation before the men are permitted to load the coal is the most efficient method of preparation.

Jan 1, 1936

By W. E. Bron, E. S. Machlin

GRAIN boundary migration in V-shaped thin specimens of high purity silver was studied. Each specimen contained two crystals having the relative orientation: (111)A/(111)B; (ll0)A/(101)B. The boundary between these two crystals varied between a continuous curved and an alternating two plane interface. The plane interfaces were oriented parallel to (101)A/(011B) and (121)A/(211)B. Traces of these planes are shown in Fig. 1. Evidently the two plane interface, although of higher area, comprises lower total interface energy than the average curved boundary it replaced. The plane boundaries were found to move at 650 °C to consume the broad segment of the V opposite to the direction of interface area and energy decrease. On investigation, using the thermal etching technique of Hendrickson and Machlin,1 it was found that the outer grain contained 8.3x108 more dislocations per cm" than the grain at the apex of the V. Consequently, the boundary moved to decrease the strain energy associated with the difference in dislocation density across the boundary. The rates of motion of specific {110} and {112} boundaries were measured during interrupted anneals at 650°C by referring the position of the boundaries to each other and a fiducial line on the specimen surface. The measured rates of motion are 0.075 and 0.025 mm per hr for the {110} and {112} boundaries, respectively. Plots of grain boundary motion vs time of annealing show straight lines with little deviation of data points from these lines.

Jan 1, 1957