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Executive JOHN M. LOVEJOY, Chairman ERLE V. DAVELER G. B. WATERHOUSE WISER JUDSON WILLIAM WRAITH J. V. W. REYNDERS, Consultant Finance HENRY KRUM, Chairman PAUL D. MERICA R. M. ROOSEVELT H. G. MOULTON, Consultant Admissions. RALPH M. ROOSEVELT, Chairman GEORGE D. BARRON, Vice-chairman JOHN L. CHRISTI PHILIP KRAFT W. A. SINSHEIMER

Jan 1, 1936

Under the sponsorship of the U.S. Department of Energy, a project was completed in 2005, which studied the use of a special pneumatic capsule pipeline (PCP) system, driven by linear induction motor (LIM), for transporting minerals and/or mine wastes. In this study, the pipeline is a rectangular tube of 1m × 1m cross section. The capsules are similar to railroad cars running on small rails imbedded in the tube. A LIM is placed AT the entrance of the tube to transfer power electro-magnetically from the LIM to capsules. The capsules going through the LIM, propelled by the electromagnetic field generated by the LIM, move faster than the air and hence impart energy into the airflow. This in turn pushes the capsules in the tube forward. When the tube is long (say longer than 10 km), additional LIMs may be needed along the tube to serve as booster pumps. An advantage of using LIMs instead of blowers as used in ordinary PCPs is that capsules can pass through the LIMs unhindered. This enables the use of booster pumps for long tubes. It also enables PCP to achieve much higher cargo throughput than that of PCPs using blowers, thereby reducing unit cost ($ per ton-km). Advantages of using capsules with steel wheels running on steel rails in the tubes including: (1) contact friction is only about one-fifth of that using rubber tires, thereby conserving energy, (2) capsules can run at a much higher speed than those using rubber tires without overheating and damaging the tires, and (3) rails make capsule motion control simple; they restrict lateral movement of capsules, and make branching easy-by using standard rail crossing equipment. This advanced PCP system combines the advantages of LIM with the advantages of rails, resulting in a super-efficient tube system having throughputs an order of magnitude greater than that of conventional PCPs, and having an energy efficiency better than railroad transport. Analysis shows that the system is highly cost-effective when throughput is high-at least 5 million tons per year. The system is most suitable for long-distance transportation of minerals (including coal and flyash) and wastes (including both mine wastes and municipal solid waste).

Jan 1, 2014

By F. J. Chernosky

Most previous studies of coal flotation utilized chemically pure reagents. Since such reagents are not available in quantity, a study of various wmmercially available reagents as frothers was undertaken. Flotation procedures similar to those used in a large number of commercial coal flotation plants were employed. The reagents used were compared on yield-selectivity-wst basis. The selectivity was found to be relatively constant with yields above 70% but the reagent cost varied greatly. The types of reagents available were compared. In the past, a number of papers have been written on the use of various reagents as coal flotation frothers. For the most part, these have been an attempt to correlate the intrinsic chemical and physical proper- ties of the reagents or reagent groups to the floata-bility of various fine coals. Because of the type or nature of evaluations made, chemically pure reagents were normally used. Generally, these reagents are unavailable in commercial quantities. Therefore, the results obtained with these reagents were usually limited in usefulness to the plant operator or metallurgist. This paper presents the results of a study in which commercially available forms of various reagents were used as flotation frothers. Flotation procedures which would conform in general to those employed in a large number of commercial coal flotation plants were utilized. The objective of the test was to compare these reagents on yield-selectivity-cost basis, that is, 1) the yields obtained, 2) the ash levels obtained and 3) the reagent cost relating to these results. REAGENTS The reagents employed have been grouped into the following chemical classes: 1) aliphatic alcohols, 2) terpines, 3) glycols (synthetic water-soluble

Jan 1, 1963

My selection of the Australian coal industry as the theme of this Presidential Address arose from the fact that it is one of our most important mineral industries. The industry is presently prospering.M.ore coal, mostly of better quality (except for certarn power-house types), is being produced more cheaply in terms of real money than at any time in the past, and exports overseas are currently at a highlevel.In. spite of this, concern has been expressed in certam quarters about the future of some phases of the industry; for example, there has been some public comment on the selling price of our coking coal to Japan, the possible over-export of our coking coals from New South Wales, the introduction of foreign capital to develop large-scale mining ventures in Queensland, and the proposed export of substantial quantities of coking coal from the same State.Furthermore, proposals for the introduction of atomic power plants into several States well endowed with reserves of coal have given rise to comment, and recently the Department of National Development(1968) warned that insufficient attention is being paid to "orderly development and careful husbanding of the nation's coal.To reach a balanced judgment on whether these views are well founded it is essential to make a broad survey of the present position of the coal industry in the Australian economy. I therefore propose to deal briefly with several aspects, and to comment, in particular, on the important subjects of exploration and research in progress at present on Australian coals.Detailed descriptions of the Australian coalfields are to be found in existing technical publications (e.g.. Andrew, 1965; McLeod, 1965) and the data on coal reserves have been progressively revised as more accurate information has become available. In New South Wales detailed knowledge of the coal reserVes is limited to under 20 per cent of the sur...

Jan 1, 1969

By M. K. Pelser

The purpose of this paper is not so much to provide a scientific study of the selection process for the perusal of other psychometrists or industrial psychologists?the purpose is to provide line management with a practical, relatively user-friendly guide to fair and scientific selection. The main areas that are to be covered are: ? Why fair and scientific selection? ? Job analysis ? The job requirement?selection technique circle ? Assessment centres in the mining industry?the Tavistock Collieries Ltd experience. Why fair and scientific selection? Seen from a line manager?s perspective, fair and scientific selection should be pursued for two main reasons: ? to remain within the ambits of the law ? to maximize the probability of selecting the potentially most productive and efficient candidate for the job.

Jan 1, 1997

By Gary E. Slagel

The year was 1974. The event - the United States Congress was embroiled over what issues should be included in the proposed national surface mining law. The question - what should be done with underground mines? The leading bills ultimately addressed the environmental impacts associated with underground mines including provisions to protect the surface from subsidence impacts. Amid the fears that this subsidence language might discourage underground mining, sponsors of the bill were asked to explain the meaning of the provision that read "to prevent subsidence to the extent technologically and economically feasible." Was this an attempt to limit mining that caused planned and controlled subsidence? Former Deputy Director of the Office of Surface Mining, Dean Hunt, reviewed some of these historical events in a 1985 presentation before the Eastern Mineral Law Foundation. He reported that in 1974 Congressman Morris Udall took the floor to respond to these concerns expressed by other members of Congress and the industry. Mr. Hunt cited Congressman Udall's July 10, 1974 Congressional Record statement: "The House bill contemplates rules 'to prevent subsidence to the extent technologically and economically feasible.' The word prevent led to fears expressed by the Secretary of the Interior Morton, that the effect would be to outlaw longwall mining, with its obvious subsidence ... in fact the bill's sponsors consider longwall mining ecologically preferable and it and other methods of controlled subsidence are explicitly endorsed." Further, the report that accompanied the front-running bill, HR11500, provided the following clarification on the issue of subsidence prevention: "It is the intent of this section to provide the Secretary with the authority to require the design and conduct of underground mining methods to control subsidence to the extent technologically and economically feasible in order to protect the value and use of surface lands. Some of the measures available for subsidence control include: (1) leaving sufficient original mineral for support; (2) refraining from mining under certain areas---or (3) causing subsidence to occur at a predictable time and in a relatively uniform and predictable manner. This specifically allows for the uses of longwall and other mining techniques which completely remove the coal." It is clear from the preceding statements that Congress considered the removal of all the coal and causing subsidence in a predictable and uniform manner to be equal to or better than leaving support coal and causing no subsidence. While the actual provision in the bills talked of preventing subsidence, a subsequent exception made it clear that the real intent was to control it. This is evidenced in the specific planned subsidence language that appeared in the bills and ultimately in Section 516 (b) (1) of PL95-87, the Surface Mining Control and Reclamation Act. It reads: "...adopt measures...to prevent subsidence ... except in those instances where the mining technology used requires planned subsidence in a predictable and controlled manner..." In spite of this historic record that supports controlled subsidence, something has been lost in the implementation. The primary focus by many regulators over the past few years has been on the "prevent" aspect irrespective of mining method being used. This has appeared to change the original intent of Congress from one of controlling subsidence to one of minimizing damage. The objective of this report is to review some of the current regulatory issues that impede full extraction mining and offer some suggestions on possible ways to deal with these issues.

Jan 1, 1986

By R. J. Hickson

From 1993 through 1999 Cyprus Amax Minerals Company successfully completed eight major construction projects around the world. Six greenfield mines were brought into production, an ongoing operation was completely modernized, and an environmental issue was appropriately remediated. The projects stretched over three continents, from arctic Russia to the Atacama Desert, from 16,000feet to sea level, from city suburbs to remote wilderness, from a low of $130 million to over $1 billion. Open pit and underground; mill and leach; gold, copper, molybdenum, and coal were all encompassed. The breadth of diversity experience from these projects inspired Cyprus Amax to create a “best practices” project management protocol, to steer corporate expansion into the next millenium. This paper summarizes those best practices, while high-lighting project management pitfalls to avoid.

Jan 1, 2000

The Mine Safety and Health Administration (MSHA) defines an independent contractor as “any person, partnership, corporation, subsidiary of a cor-poration, firm, association or other organization that contracts to perform services or construction at a mine.” Contractors that perform specific types of work are required to report the number of employees who work at coal mines and noncoal mines.

Sep 1, 2007

By K. J. R. Ford

"Significant advances in mining and metallurgical operations have occurred over the last two decades, to define ore bodies via geological mapping, mineralogical analyses, geostatistical models and resource reserve modeling. Metallurgical process measurement, controls and modeling have also significantly progressed, with advanced instrumentation, control software, data capture systems and simulation tools. This progress together with development of the science of geometallurgy has allowed geologists, mineralogists, miners and metallurgists to start working together to define geometallurgical ore units and link these to mine planning and projected metallurgical performance. However, application of full geometallurgical programs into existing mine-processing operations or into new “greenfield” projects has been slow. This is mainly due to higher costs, limited dedicated technical resources and little or no corporate leadership. Additionally, life-of-mine cash flow models, the “dollars”, have been largely driven by ore tonnage rates, pay-metal grades and fixed pay-metal percentage recoveries, with few or no geometallurgical parameters included.Here defined, the “electrons” represent intrinsic ore characteristics embracing chemical composition, mineralogy, gangue components and their associated fundamental metallurgical processing phenomena. With its ever expanding treasure chest of measurement and modeling tools, geometallurgy paints a much clearer picture of the “electrons” for the geologist and metallurgist. But to fully understand and realize the real net value of ores over the life of a mine, a comprehensive link of “electrons to the dollars” is essential. Intrinsic characteristics of geometallurgical ore units are by definition linked to their metallurgical processing, but importantly need also to be related to operating costs, capital requirements and revenue.This paper discusses this important linkage under topics of ore geology and mineralogy, metallurgical processing, waste disposal, environmental issues, metal refining, project engineering and lifeof- mine models. Topics are illustrated by multi-metal references and by case examples from gold ore heap leaching and manganese ore smelting projects. 1"

Jan 1, 2013

By T Davids, B J. J Botha

The presence of an extensive soft siltstone layer in the middle of the inter-burden sequence of rocks at Syferfontein Colliery in South Africa prompted tests to determine the effect of different mid-column decks of inert material in the siltstone layer. The objective was to achieve significant cost savings in explosives use whilst not degrading dragline productivity. An important factor that had to be considered was that the initiation systems available in South Africa are not accurate enough to ensure simultaneous initiation of explosives decks in a hole.

Jan 1, 1994

By E. O. Binyon

"INTRODUCTION The Gibellini manganese—zinc-nickel deposits, are in southeastern Eureka County, Nev, T. 15 N., R. 53 E. M.D.B.M. 27.5 miles south of Eureka, the county seat.The partly explored deposits, locally known as the Black Iron or Gibellini property, were examined in May 1944 by an engineer 3/ of the Bureau of Mines, who recommended that the deposits be explored further by means of core drilling. The proposed program called for drilling six diamond—drill holes, or eight if necessary, and for trenching at two places — 200 feet northeast and 280 feet west of the shaft on the main deposit.In 1946 the project was set up, and In July, of that year diamond drilling as started. Six holes were drilled for a total length of 1,198.5 feet. No trenching or other exploratory work as done. Work on the project was stooped. October 30, 1946.OWNERSHIPAccording to county records, the property comprises a group of 13 unpatented lode claims, and ownership is divided among Louis P. Gibellini,Louis P. Gibellini and wife (both of Eureka, Nev.), and the International Smelting & Refining Co., of Salt Lake City, Utah. Five claims of the group - the Black Iron No. 1, Black Hill No. 2, Manganese No. 3, Flat No. 1, and Flat No. 2 - are owned by Gibellini. Three claims - the Black Hill No. 1, Black Iron No. 3, and Manganese No. 4 are owned jointly by Mr. and Mrs. Gibellini, and the International Smelting & Refining Co. owns the remaining five - the Black Iron No. 4 and No. 5, and Black Hill Nos. 4, 7, and. 9."

Jan 1, 1948

By Murat Baydogan

Effect of retrogression and reaging treatment on hardness and stress corrosion cracking resistance of 7075 aluminum alloy was investigated. As received 7075 alloys in T6 temper condition were retrogressed at 170, 220, 240 and 380°C for different durations between 15 s and 60 min. Subsequent reaging was made at the T6 aging condition. Treated materials exhibited higher hardness and better stress corrosion cracking resistance than T6 temper in a wide range of retrogression temperature and time. The highest hardness was obtained after retrogression at 170°C for 210 s followed by reaging, corresponding to 20% hardness improvement. Improvement in stress corrosion cracking resistance of the alloy by as much as 85% was also observed. In this paper, improvements in hardness and stress corrosion cracking resistance are discussed on the basis of the microstructural changes during retrogression and reaging treatment.

Jan 1, 2006

1. Domestic Production and Use: In 1980, 13 companies operated 33 primary aluminum reduction plants, with 3 firms accounting for 62% of production. Washington, Oregon, and Montana accounted for 30% of the total production; Texas, Louisiana, and Arkansas 19%; Tennessee, Alabama, and North Carolina 15%; other central and eastern States 36%. Based on published producer prices output of primary metal in 1980 was valued at over $7 billion. Aluminum consumption by 25,000 firms was centered in the East Central United States. Packaging accounted for an estimated 26% of domestic consumption in 1980, building 22%, transportation 21%, electrical 12%, consumer durables 7%, and other uses 12%.

Jan 1, 1981

By A. D. Pelton, Y. -B. Kang, S. A. Decterov

Computerized thermodynamic databases for solid and liquid metal, slag and solid oxide phases in the Al2O3-CaO-CoO-CrO-Cr2O3-FeO-Fe2O3-MgO-MnO-NiO-SiO2-S system have been developed by critical evaluation/optimization of all available phase equilibrium and thermodynamic data. The databases contain parameters of models specifically developed for molten slags, liquid steel and solid oxide solutions such as spinels, pyroxenes, olivine, monoxide (wustite, periclase, lime), corundum, etc. By means of the optimization process, model parameters are found which reproduce all thermodynamic and phase equilibrium data within experimental error limits. Furthermore, the models permit extrapolation into regions of temperature and composition where data are not available. The databases are automatically accessed by user-friendly software that calculates complex equilibria involving simultaneously slag, metal, refractories and gases, for systems with many components, over wide ranges of temperature, oxygen potential and pressure. A short review of the available databases is presented. The critical evaluation/optimization procedure is outlined using the Al2O3-CaO-FeO-Fe2O3-SiO2and Al2O3-CaO-MnO-SiO2systemsas examples. Several applications of the databases to deoxidation of iron and to inclusion control in steel are discussed. Keywords: thermodynamics, phase equilibrium, phase diagrams, databases, ferrous metallurgy, steelmaking, inclusion control, slags, oxide systems.

Jan 1, 2004

By B Murphy, A Uliana, P STrgio de Oliveira, G Ara·jo de Souza Franco, T Miettinen

Outotec has performed numerous research and development projects and various surveys in the study of reverse iron ore flotation. Over the past four years their TankCell-70 and TankCell-160 flotation cells at the Germano concentrator of Samarco in Brazil were extensively surveyed. These surveys have revealed some extreme operating conditions in reverse iron ore flotation and are the subject of this paper. Some of the findings include large variations in the content of solids in the various flotation stages. At the bottom of the cleaner cells, the content of solids by weight reached over 60 per cent, whereas at the bottom of the scavenger cell this was less than 50 per cent. Froth carry rates were also significantly different in the various flotation stages. In the case of coarse material, the scavenger cells operated at a froth carry rate of over 40 t/h.m2. With fine material, however, froth carry rates of less than 10 t/h.m2 were measured. High froth carry rates caused significant changes in the residence times at Samarco. In the rougher cells, the fifth cell had more than double the residence time of the first cell. This was even more pronounced with the scavenger cells, where the second cell had more than triple the residence time of the first cell. High froth carry rates also caused losses in iron recovery. As a consequence of such findings, it appears that different rules apply in the sizing of reverse flotation circuits compared to direct flotation circuits. Different operating parameters (mixing intensities and air flow rates) must also be used in the rougher, cleaner and scavenger cells in order to optimise the metallurgical performance. Outotec has also been working on a number of new technologies aimed at improving the metallurgical performance of iron ore reverse flotation circuits by increasing froth carry rate and decreasing fine iron entrainment.CITATION:Miettinen, T, Uliana, A, Ara·jo de Souza Franco, G, STrgio de Oliveira, P and Murphy, B, 2013. TankCell flotation at SamarcoÆs Germano concentrators, in Proceedings Iron Ore 2013 , pp 441-444 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 12, 2013

Standard petrographic profiles for many Permian seams from New South Wales and Queensland have been drawn up. The standard profiles of seams of the same age and from one or more coalfields were used to compile an idealized or type seam sequence for those coals in which more than half the seam profiles were similar to one another. A marked similarity existed between at least 7 of the 10 type seam sequences formed.The configurations of the vitrite-plus-clarite contents of the plies of 95 per cent of the seams could be formed from different arrangements of 3 basic sequences. These were...

Jan 1, 1970

By C. D. Anderson

A variety of processing technologies exist for recovery from both primary and secondary sources of rhenium. Currently, there are no known primary rhenium deposits, thus, the method in which primary rhenium is produced is dependent on the commodity of which it is a byproduct, e.g., copper, molybdenum, uranium, etc. In addition, focus on the recovery of rhenium from secondary sources, such as alloy scraps and catalysts, is continually growing. This paper presents a review of both primary and secondary processing technologies for the recovery of rhenium. Key Words: Rhenium, Ammonium Perrhenate, Extractive Metallurgy

Feb 27, 2013

By Oliver Bowles

From remote antiquity stone has been employed for structural, ornamental, and memorial purposes. It was, and still is, so used because of its availability in innumerable localities and its architectural adaptability, dignity, substantiality, and durability. The principal varieties of stone used are granite, marble, limestone, sandstone, and slate. This report deals with granite. OCCURRENCE AND CHARACTER OF GRANITE Granites usually have been classed as igneous rocks derived from molten masses or magmas, but there is wide evidence that the origin of some granites may be attributed to regional metamorphism of preexisting rocks, rearrangement and recrystallization taking place without a liquid or molten stage. In any event granitization is a slow, deep-seated process.

Jan 1, 1956

By E. Northcott, F. N. Oberg

By electrostatic separation, course Florida pebble phosphate, too lou-grade to find a ready market, can be upgraded to a satisfactory saleable product. Pebble running from 60 pct bone phosphate of time may be upgraded to 73 to 77 pct BPL depending on the mineralogical. structure of the pebble and the nature of the silica innpurity. High-grade concentrates from Florida pebble phosphate deposits have long been recovered by wet methods. When work was begun in the field, only the coarse pebble (generally +1 mm) was re- covered. In the 1920's a froth flotation process was developed to separate quartz from the finer phosphate fractions, but this method proved unsatisfactory for treating the intermediate fraction (—1 mm +35 mesh). Consequently various other processes were adapted, including agglomerate tabling and spiral separation of reagentized feed. Today the three processes are used—washing and screening for coarse pebble, tabling or spiraling for intermediate sizes, and flotation for —35 mesh material.

Jan 1, 1959

By W. W. Adams

Lower accident rates were the outstanding feature. of the second annual sand and gravel safety competition conducted in 1930 by the United States Bureau of Mines in cooperation with the National Sand and' Gravel Association. Both the frequency and, severity rates for accidents were greatly reduced as compared with those shown by the first year's contest, that for 1929. Three times as many plants were enrolled, and the number of man-hours of work represented was more than doubled. Seventy-six sand-and-gravel plants, situated in 20 States, participated in the Competition, as compared with 26 plants, located in 13 States, in the year before. The number of man-hours of employment, which indicated the amount of exposure to occupational hazards, was 4,915,592, an increase of more than 100 per cent over the previous year's total of 2,259,572 hours. The frequency of accidents declined from 74.4 per million hours for all plants enrolled in the first year's contest to 42.7 per million man-hours for all plants enrolled in 1930. The accident-severity rate was reduced from 9.7 days of disability per thousand man-hours of exposure in 1929 to 5.9 days of disability per thousand man-hours of exposure in 1930. The actual number of accidents reported for 1930 by 76 plants included four deaths and 206 injuries whereas the 26 plants that were enrolled in 1929 reported three fatalities and 165 injuries. Under the rules of the contest all "lost-time" injuries are reported--that is, all injuries that disable an employee for more than the remainder of the day on which the accident occurred. If the employee is physically able to resume his work on the day following the accident, the injury is not classed as a lost-time injury. The contest covered accidents and man-hours worked by all employees at the plant who were employed by the same company, and included work up to the point of delivery of the material directly to consumer or to independent agency of transportation--in other words, to point of relinquishment of control of the material by the producer.

Jan 1, 1931