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By V. Ramachandran

In view of the increasing environmental regulations that have been promulgated in the last 30 years, non-ferrous smelters and refineries have learnt to handle effectively the process waste streams that need to be bled from the system for impurities' control The cations of concern are copper, lead, zinc, cadmium, mercury, thallium, nickel, silver, sodium and potassium. Anionic species of arsenic and selenium also need to be addressed, Sulfates and chlorides-not a major concern at present-have come under scrutiny in the recent past. The current paper reviews several treatment options with reference to a) types of waste streams processed b )process chemistry c)discharge options and recovery of treated water and d) sludge disposal The long term goal of any smelter and/lor refinery should be to achieve zero liquid discharge from the plant. Methods to obtain zero discharge are discussed.

Jan 1, 2003

By Christie A. Callender, Harry M. Dahl

The Hobson uranium deposit is located in Karnes County, Texas, along the prominent south Texas uranium trend. The uranium mineralization occurs in the Deweesville Sandstone of the Whitsett Formation of the Eocene Jackson Group. The host rock is a friable, fine-grained, well-sorted, highly porous and permeable sandstone interpreted to be an ancient beach deposit. The sandstone contains significant volcanic constituents and ranges in composition from arkosic to tuffaceous. Locally, the host sandstone contains hard, dense opal cement. Bentonitic shales underlie and overlie the mineralized sandstone unit. Geometrically, the Hobson uranium-bearing zone resembles an elongated roll front type deposit. Chemical uranium values compared with gamma ray equivalent uranium values indicate that the uranium has been dissolved from the updip side and precipitated on the down- dip side of the roll front. Details of the uranium mineralization were studied using thin section microscopy, autoradiography, x-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS) techniques. The uranium mineralization occurs in the pores of the sandstone, as grain coatings and as replacement of sand-size and smaller grains. It is commonly associated with pyrite and other opaque minerals. Other favored hosts for uranium (other than pore openings) appear to be clay aggregates, altered rock and glass fragments, and carbonaceous plant debris. Aggregates of coffinite were identified by XRD and SEM/EDS analyses. Some uranium mineralization also appears to be dispersed and is postulated to be adsorbed on the clay and carbonaceous matter.

Jan 1, 1985

THE Woman's Auxiliary now has its own publica-tion, a monthly news letter that is mailed direct to all its members. It is a lively and readable sheet. Any member of the Auxiliary failing to receive it should communicate with Mrs. J. E. Johnson, Jr., 49 Church Lane, Scarsdale, N. Y., and get on the mailing list. The detailed reports of the meetings will hereafter ap-pear in the News Letter rather than in MINING AND METALLURGY. The regular Board meeting held on March 3, with Mrs. Barron presiding, was well attended and the re-ports of the committees, and from local sections, showed a keen interest in the work. of the organization. Steps are being taken to endow a "Mary Young Westervelt Scholarship," libraries are being built up in mining towns, and interesting reunions .are being held by the members in the various local sections. The Auxiliary is filling an important place and doing it well. Women of the families of Institute members not already affili-ated with it would find it pleasant to get in touch.

Jan 4, 1927

By John Birkinbine

Secretary's Note.—In printing this paper in the present volume, the figures given in the pamphlet edition have been brought more nearly up to date, the product of 1899 being in many instances inserted. Iron-Ore Resources. In a paper presented to the Institute in 1897,* I discussed the iron-resources of the United States as then developed, calling attention to some principal sources upon which other countries depended. The following statement will give a general idea of the amounts, as compiled from the latest official records, of ores won, and metal produced, in the nations which are important contributors to the world's output. Unfortunately these are not all contemporaneous, since in some countries the statistics do not appear until after one or more years. The statement covers not only pig-iron and iron-ore, but also manganese-ore —the manganese mined being principally used in the production of spiegeleisen or ferro-manganese, and these alloys being generally included in the pig-iron output. Table I, which epitomizes the present situation, shows respectively the countries and the quantities of iron-ore and man-

Jan 1, 1901

By Paul Billingsley

When I was an undergraduate at the Columbia School of Mines, the mining curriculum was subdivided into two major branches's known respectively as the Metallurgical and the Geological Options, which diverged rather widely as the course progressed. When I duly elected the Geological Option, I believed, I am sure, that this divergence would continue throughout the years. The facts have proved otherwise. The mining industry is a closely knit entity in which the search for its raw matcrials, called mining geology, cannot be separated from the conversion of these raw materials into marketable form, called metallurgy. The mining geologist searches for materials which the metallurgist can utilize, and only such; and whenever an advance in metallurgy opens the gates for new matcrials, the geologist's problem is correspondingly modified. No better instance of this relationship can be given than that seen in the Salt Lake region in recent years. Our mineral industry here is of long standing. The three principal tributary districts, Bingham, Park City and Tintic, were discovered in the 1860's and have been vigorously and intelligently developed for many decades. Their production has made the Salt Lake valley one of the world's great smelting centers. The maintenance of this industry has for years depended upon the continual development of new orebodies to take the place of those being extracted. Intensive exploration in the old districts has been supplemented by prospecting in outlying districts of lesser prominence. Many new orebodies have been discovered, such as those of the Daly West, Silver King, and Judge mines in Park City, the Utah Apex in Bingham, and the Sioux, Colorado Chief Consolidated and Tintic Standard in Tintic. New mines in other districts have been discovered also, but without affecting the dominánce of the three major districts. In all cases discoveries, to be of value, had to be of ore amenable to treatment in the available metallurgical plants. This meant that, for the most part, zincy ores, both oxide and sulfide, must remain untouched, and also that ores high in iron and ores high in silica had a fictitious value, either high or low, set by the balance of these

Jan 1, 1928

By J. M. Hird

By blending phosphogypsum with thickened mill clays, Texasgulf has successfully resolved the problems of gypsum disposal and reclamation of mined-over areas. In the process, clays are thickened to 10% solids through high rate thickeners, mixed with gypsum from a drained gypsum pile (75%) and a direct discharge from belt filters (25%), then pumped to mined-over areas. The blending of clays and the low pH gypsum yield a mixture with a pH of about 7. Dewatering is rapid to 40-45% solids within 3 months. The material spreads with very shallow slopes and within a year desiccation by high flotation ditching equipment is possible. The artificial soil is classified as a silty loam in texture, lacking only in nitrogenous nutrients. The soil material has proven to support many field crops including small grain, corn, alfalfa, and grasses. Sycamore, green ash, sweetgum and bald cypress have done well in 3 years of growth. The nitrogen source for tree growth will be made up through an alfalfa cover.

Jan 1, 1993

By David M. Cregger

The performance of the nation's first geologic repository for Commercial High Level Waste will be evaluated in a variety of ways which will involve the use of the state-of-the-art thermomechanical computer codes. Elastic properties of the host rock and the materials surrounding the repository are required for this numerical modeling effort to assess both near- and far-field effects. Only limited laboratory testing is possible, however, making it extremely beneficial to expand the data base by calculating dynamic elastic properties from available geophysical well logs. Elastic theory dictates that for an isotropic solid there are only two independent variables in addition to mass density, namely the compressional velocity, the shear velocity, and Poisson's Ratio. Compressional velocity and density are readily measured by geophysical well logs or in the lab; the crux of the solution requires measuring or determining either the shear velocity or Poisson's Ratio. Examination of acoustic propagated shear waves measured during confined compression testing demonstrates that Poisson's Ratio is a fundamental lithology-dependent parameter. Once a rock mass is appropriately classified, application of the laboratory derived dynamic Poisson's Ratio will yield a continuous and reasonable in situ modulus from acoustic and density logs. For preliminary characterization and assessment of the mechanical properties of rocks within the subsurface, and for studies of rock quality, this method is sufficiently accurate. The general availability of acoustic and density logs from wells logged for other purposes has made the application of this method desirable.

Jan 1, 1984

By Eugene McAuliffe

In the year 1581, the counselors of King Philip of Spain suggested to that monarch that a canal across the Isthmus of Darien would open the west coast of the South American continent to Spanish miners and explorers, enlarging and expanding the flow of precious metals then just beginning to trickle across the path cut by Spanish Conquistadors, from old Panama to Puerto Bello on the east coast. The King sent out a party of surveyors and explorers under the command of a young engineer, Savadaerro, who returned after two years, reporting upon a location for a canal which was virtually adopted by the French engineers employed by De Lesseps, who in 1877 commenced the work of constructing the Panama Canal-296 years after Sava- daerro's first survey was begun. The suggestion for an Isthmian canal, made to the king at a time when Spain was a proud, virile nation and when that country was contending with England in the fields of discovery and conquest, represents a measure of vision that has never failed to intrigue the imagination. That the young Spanish engineer recommended an undertaking so gigantic in conception that it took three and one-third centuries for its completion from the time it was first visioned matters little. In the day of Philip of Spain,

Jan 1, 1932

By Lewis L. Oriard

The authors outline the development and application of blasting methods put into use 11 years ago at the Berkeley Open-Pit Mine, Butte, Montana. The blast design uses a very short delay (5 milliseconds) between detonation of explosives charges, a feature challenged several times in principle despite its success for Anaconda. Concern is expressed over the categorical rejection of very short delay blasting which can make the difference between success and failure of major mining operations. There is ample evidence to show that the method can be used successfully and not violate the concerns of the public.

Jan 1, 1980

By E. J. Wasp, N. T. Cowper, R. A. Davis, W. F. McDermott

On October 26, 1967, the world's first long distance iron ore slurry line was put into service by Savage River Mines. The commissioning of this $5 million installation climaxed three years of development, testing, and construction. The mine and concentrator are located approximately 30 miles from the town of Waratah in a rugged semi-mountainous terrain. The open pit mine will produce approximately 5 million long tons a year of crude ore, which is ground in autogenous mills, separated magnetically, thickened and prepared for the pipeline. The 53-mile pipeline transports the 2,250,000 tons of concentrate north to Port Latta. The Port Latta facilities include the receiving, storage and thickening equipment for the slurry as well as filtering, balling and pelletizing equipment to produce the 2,250,000 tons of high grade iron ore pellets. Five vertical shaft furnaces are used for pelletizing.

Jan 1, 1969

Societal expectations about how the industry operates and treats its people will be a key driver in the development of the Australian mining industry over the next 20 - 30 years (Moffat, Mason and Littleboy, 2009). Understanding these expectations will be critical in maintaining what much of the minerals industry calls its 'social licence to operate', or its public acceptance or approval. Yet what constitutes this social licence is poorly articulated, with little published research exploring the concept at a local operational level or at the national level in Australia or internationally. This research aimed to explore the societal expectations of the mining industry in Australia and test a participatory methodology to articulate them. Three workshops were conducted with a sample of 24 members of the 'Australian voting public' to explore community objectives for the onshore exploration and mining industry, and the underlying expectations for how the industry should operate in the future. Qualitative analysis of this data revealed three overarching objectives for the onshore mining industry held by participants. They thought that the industry should: advance Australia's national interests (including social well-being); minimise environmental impact, and; act in a socially responsible manner. Within each of these three key themes, or objectives, a number of tensions were evident in the views of participants regarding the trade-offs they are willing to make to secure economic benefit from mining, as well as the basic conditions for socially acceptable mining. These data provide an insight into the conditions for a national social licence in Australia for the mining industry, and the means for its realisation.

Jun 1, 2010

By Andrew J. Neale, Chelvan Veloo

P.T. Freeport Indonesia currently operate a 600,000 t/d mining and 125,000 t/d milling operation in the remote highlands of Irian Jaya, Indonesia. The isolated location and generally difficult working conditions make for challenges not encountered in most North American operations. In spite of this, the mill technical groups have been able to develop and maintain a highly effective level of plant wide automation. This has been achieved through the appropriate selection of available technologies and the implementation of innovative management practices. This paper provides an overview of the control systems currently installed and focuses on those practices which have resulted in the long term success of process control at Freeport.

Jan 1, 1997

By Fredrick C. Kruger

Introduction This surprisingly little-known group of minerals, the nonmetallics, so-called for their lack of metallic luster, is the largest group of the mineral kingdom, and cinstitutes perhaps 75 percent of all mineral species. For the most part, these minerals are compounds of the common acids, oxides, hydroxides, and two elements, carbon and sulfur. The list of the non- metallic minerals, therefore, is very long. It includes the borates, carbonates, chlorides, fluorides, nitrates, phosphates, silicates, sulfates, and less commonly, arsenates, chromates, molybdates, suliides, tungstates, and vanadates, the latter groups, and many of the oxides, being sought principally for their metal content. Those nonmetallics used commercially are generally called the industrial minerals, although in addition this term also includes a considerable group of rocks. The list of industrial minerals and rocks is continually growing as new uses are found, and it now numbers over 300 commodities. The industrial minerals industry has developed since about 1920. There- fore, the development has been fast, and it has been more or less parallel with the development of the art of minerals beneficiation. General Discussion of the Group This group is so heterogeneous that it has defied logical, or widely accepted, classification, whether by origin, composition, or end use, and perhaps for this reason the industrial minerals generally have received short shrift in both teaching and research. Except for those involved with asbestos, cement, fertilizers, gypsum, salt, sand and gravel, few large companies have deigned to enter the field, and consequently most industrial minerals have been developed for the most part by the small operators or entrepreneurs. Yet surprisingly, except for one war year, the nonmetallics have always surpassed the metals in value and tonnage (Fig. 1). One main characteristic that most of the nonmetallics have in common is direct sensitivity to labor and transportation. In other words they are characterized by large bulk and low-unit value, and hence have what might be termed a "place value".

Jan 1, 1971

By B. G. Russell

A wide range of minerals is found within the Republic of South Africa, many of which are exploited to a greater extent than in similar deposits found elsewhere. It is often asked whether this is atributed to the high grade of the ores encountered in this country, or whether such factors as fiscal and Infrastructural incentives create an economic climate that has en bled the mining industry to successfully extract and market minerals at a profit. This paper views South Africa's mineral resources in a regional and global context In an attempt to place the country's geological wealth in perspective. It represents the author's own Views, and not necessarily those of the Department of Mine al and Energy Affairs.

Jan 1, 1986

By Fuad S. Maayeh, Robert J. Evans, Paul M. Yavorsky

A description and capabilities of the Mine Roof Simulator at the Pittsburgh Mining Technology Center is illustrated for testing longwall roof support equipment. This unique Mine Roof Simulator has the capacity to exert 3 million lbs. of compressive force vertically and 1.6 million lbs. of force horizontally to simulate loads on hydraulic supports typically found in longwall mining. The supports that undergo testing are instrumented with strain gauges and photoelastic coatings such that critically strained areas become readily apparent. These critically strained areas are redesigned or retrofitted with appropriate reinforcement and retested. A data base will be accumulated from several support designs that will lead to an optimized design that will have the potential to reduce downtime by malfunctions of supports and thus increase productivity. A typical test procedure and analysis is given for a two leg 350 ton shield along with a description for placement of strain gauges, displacement gauges, and hydraulic pressure monitors for critical sites.

Jan 1, 1982

By D. R. Wilburn

The Bureau of Mines investigated the potential availability of magnesium from 45 properties in market economy countries (MEC's). The 38 significant deposits evaluated have demonstrated resources of approximately 29 billion short tons (st) magnesium-bearing material containing 416 million short tons (MMst) magnesium oxide (MgO). Using data it gathered, the Bureau determined the magnesium production potential for each property including a 15-pct rate of return on invested capital. Total and annual availability assessments for the next 30 yr were completed for magnesium (Mg) metal, deadburned MgO, and caustic calcined MgO. At a January 1984 market price of $1.34/Ib Mg metal, the properties evaluated could economically produce an estimated 13 MMst Mg metal. At a market price of $400/st nonmetal magnesium product, these properties could economically produce 109 MMst deadburned MgO and 43 MMst caustic MgO. These properties could produce approximately 301,000 st Mg metal, 3.0 MMst deadburned MgO, and 430,000 st caustic MgO annually at current full production levels and 1984 market prices until at least the year 2000. Total 1984 MEC production assessed in this study was 153,000 st Mg metal and 4.3 MMst nonmetallic MgO products.

Jan 1, 1986

By Susan B. Bealko

Mining provides a large part of the energy and raw materials that feed this Nation's economy. Copper pipe, concrete, and window glass serve as well known examples of the reliance on minerals in modern society. Less appreciated, but as important, are the hundreds of mined commodities that are an integral and necessary part of everyday products, ranging from medicines and computers to carpet and paper. Coal is a major portion of the country's energy mix today, as it will likely continue to be in a future hydrogen-based economy. The domestic mining industry also provides strategic minerals that are important for the Nation's security. The processes to recover these mineral commodities are among the most demanding and complex in an industrial society, and this inherently dangerous industry has historically had the highest risks of fatality and injury. The mining industry has been undergoing some trying and challenging times because of the recent mine disasters in the coal fields. These events have been alarming in light of the strong and encouraging safety record that has characterized mining in the United States for most of the past decade. While mining communities deal with their grief, mine operators, government regulators, and other safety personnel, set about trying to determine why these fatalities occurred. Subsequently, the mining industry is currently experiencing changes in legislation at an unusually rapid pace. The most recent regulatory changes are the Mine Improvement and New Emergency Response Act of 2006 (MINER Act) and the temporary emergency standard for mine seals. The new mine safety laws call on the nation's mines to adopt certain procedures and safety technologies immediately, or as soon as they become commercially available. Putting all the provisions in place from these new laws is a major undertaking, and will necessitate strong collaborations and partnerships among mine operators, manufacturers, regulatory and research agencies, labor unions, and community groups. It is against this background that Prevention through Design (PtD) components for the Mining Sector are recommended.

Jan 1, 2008

By Alvin Kaufman

Increased exploration in Alaska has resulted in many requests to the Bureau of Mines for facts about the mineral resources and mining conditions in the Territory. This report presents information about the minerals of Southeastern Alaska and the factors that affect development of a mining industry in that area. Southeastern Alaska is a narrow coastal strip of rugged mountains and many islands. The climate is mild, with an average annual temperature of 40° and heavy rainfall. Geologically, the region is favorable for deposition of ore; geographic-ally, it is difficult to prospect and to develop, except along areas immediately adjacent to the coastline.

Jan 1, 1958

By T. A. Read, H. K. Birnbaum

STRESS-induced twin boundary motion in the AuCd ß'phase (52.5 at. pct Au 47.5 at. pct Cd having an orthorhombic structure (space group D h)' was discussed for the case of transformation twins.' Mechanical twinning, i.e., introduction of new twin orientations by the applied stress was sometimes observed in the ß' phase which contained two transformation twin orientations. (See Ref. 2 for experimental details.) The transformation twins terminated at the mechanical twin boundary; the two initial orientations having been twinned to the new orientation as shown in Fig. l. In a "hard" tensile instrument, formation of each mechanical twin was accompanied by a sharp drop in load (and an audible click) resulting in a typical serrated load-extension curve. The mechanical twins increased in width and additional twins were nucleated as the load increased until the entire specimen was occupied by the mechanical twin orientation. A restoring force2 caused the mechanical twin and transformation twin boundaries to return towards their initial configuration on releasing the load. In a stabilized specimen* the total strain introduced by mechanical twinning was recovered on releasing the applied stress. Initial and final microstructures were identical. After decreasing gradually to a critical width, mechanical twins suddenly disappeared accompanied by audible clicks and sharp increases in load (measured at a constant rate of crosshead motion in a "hard" machine). Mechanical twins could be stabilized in any position by maintaining the applied load for a sufficient time, indicating a decrease in restoring force with time similar to that observed for transformation twins.' Orientation relationships for mechanical and transformation twins were determined and are shown in Fig. 2. The mechanical twin, T3, was twin related to transformation twin, T,, by reflection in (1ll), and twin related to transformation twin, T2, by reflection in (111)T, . T, was related to T, by reflection in(ll1)T1 . The "average" mechanical twin composition plane lay several degrees from (1ll), . In every specimen which mechanically twinned, orientation T3 was most highly favored by the applied stress, i.e., it was the twin orientation which provided the greatest change in length compatible with the direction of applied stress

Jan 1, 1961

By Robert R. Dorfler

AMPS[. has completed a rationed grinding ball test in a 2.93 m x 2.93 m ball mill at Climax Molybdenum Company. The test consisted of purging the ball distribution formed by charging 100%, 76 mm carbon steel balls with a distribution formed by charging 50% 76 mm and 20% 51 mm alloy steel balls. The resulting change in ball surface area yielded improvements in both tons ground and fineness of grind with a significant reduction in total ball consumption. This paper summarizes preliminary studies leading to the plant test, grinding efficiency results, and future plans to optimize the ball charge.

Jan 1, 1981