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THE decades immediately before and after the end of the nineteenth century (1890-1910) were a period of increased activity in mineral industry education. One reason for this, undoubtedly, was the rapid increase in mineral production in the decade 1880-1890; pig iron and copper production tripled; coal, lead, and zinc output more than doubled. Most of the other mineral substances followed the same general trend. Aluminum production began in 1886; petroleum output, which in 1888 was less than it was in 1882, almost doubled in the next three years. Gold alone showed no appreciable change until its discovery at Cripple Creek in 1891, followed by the Klondike in 1896, brought to boiling a public interest in minerals that had been simmering for some years previously. The first cyanide plant in the United States was erected at Bodie in 1892, and the first chlorination plant at Cripple Creek* the next year. Silver- lead smelting had already greatly developed, and the metallurgy of copper was almost transformed. The hearth area and smelting capacity of copper reverberatory furnaces more than quadrupled between 1878 and 1894; matte converters were first erected at Butte in 1884. Copper production of the United States in 1899 was 20 times that of 1872. While it was the increased technology used in mineral production that really made the field attractive for educated young men, undoubtedly they did not realize that, and were impressed mainly by the quantitative increase in output. Another factor was the increased general interest in engineering education; three times as many men took engineering degrees in the United States in 1890 as in 1880; 1892 showed almost a 56 per cent increase over 1890. Industry had come to recognize that technical training was worth while. The mineral industry lagged somewhat at first; the total number of mining degrees

Jan 1, 1941

By Walther Rodolfo Ventura Gallardo

El presente texto señala un ejemplo de desembalse de relaves desarrollado en el campamento Comihuasa, perteneciente a la Compañía Minera Cautelosa S.A., donde se afectó las condiciones naturales de los ríos, población y actividades productivas. Por tal motivo, se ejecutó un plan de acción inmediato y de corto plazo que consiste en un estado de alerta de los establecimientos de salud, protección del ganado para evitar que beban agua de los ríos contaminados, inventario de animales afectados por falta de agua segura para su consumo, construcción de abrevaderos, abastecimiento de agua para ganado, recojo de relaves y suelos afectados, su disposición adecuada y segura, rehabilitación de suelos, recuperación de pastizales, repoblamiento de especies acuáticas en los ríos, supervisión del cumplimiento de las medidas de remediación, y recuperación de la calidad ambiental y sanitaria de los ríos.

Jul 1, 2014

By Louis J. Czel

Although lithium was first discovered by Arfwedson in Sweden in 1817, it did not reach any significant status in commercial application until 1908 when Thomas A. Edison received a patent covering the use of lithium hydroxide in alkaline' storage batteries. Edison's achievement can be regarded as a major breakthrough in the development of the lithium industry. In the years prior to 1908 lithium salts had found only modest applications in the pharmaceutical and pyrotechnic fields. The next important milestone in the growth of this net industry occurred in Germany in 1918 when Metallgesellschaft at its metallurgical laboratory at Frankfort-on-Main discovered that the addition of a few hundredths percent of lithium metal to aluminum and its alloys increased-the hardness. This brought into being a new commercial use of lithium in the manufacture of bearing metals. The new material, called "Bahnmetall" (railroad, metal), was widely used for, many years in the manufacture of bearings for railroad and automotive purposes. Its use continued until the early 1930's and there was a short-lived renewal of its production during World War II. Subsequent use of-the alloy was soon outmoded.

Jan 1, 1961

By Jon C. Volkwein

The Bureau of Mines and many member companies of the Industrial Sand Association have been working in several areas to reduce personal exposure to respirable dust. Areas investigated include ventilation, modification of hardware, moisture addition to the product, and improved housekeeping practices. Ventilation systems have been devised and shown to contain 100 pct of a tracer gas released within the hood. An industrial clean air island has been developed and shown to reduce dust levels 90 pct at the opera- tor's position, Modification of hardware on a bag filling machine has been demonstrated to reduce dust 83 pct at the machine operator's lapel. This particular development has been termed a significant advancement in the state-of-the-art of bag filling by industry representatives. Addition of moisture to dried product materials has been tested with results showing dust reductions of 90 pct are possible!, Control of the moisture addition method still needs refinement and costs may be prohibitive. Dust sampling results clearly show the benefits of housekeeping practices such as building cleaning and vacuum sweeping. Rotation of work schedules is also effective for reducing personal exposure.

Jan 1, 1985

By W T. C Kendall, H D. Ngo

Garden Well is a shear-hosted Archaean orogenic gold deposit located 100 km north of Laverton, Western Australia. The Garden Well processing plant is designed for a nominal 491 t/h milling rate and annual capacity of 4 Mt. The plant has three key innovations:1. a scrubbing circuit, expected to reduce grinding power consumption by up to 20 per cent2. a secondary cycloning/gravity circuit, providing a second opportunity for gravity gold recovery (additionally, the circuit effectively increases the leach residence time of the coarse gold bearing fraction of the leach feed by approximately 60 per cent, without any additional tankage)3. the use of mid-stream oxygenation to enhance gold recovery.The Garden Well deposit is free-milling with overall laboratory gravity/leach gold recoveries exceeding 95 per cent at a P80 grind size of 150 ¦m. Three mineralogical domains have been identified: oxide, transition and fresh, with the fresh domain having subdomains of fresh ultramafic and fresh shale. There is a high component of gravity recoverable gold in all three domains.This paper will discuss these innovations and the design challenges and the risk mitigation strategies that were adopted to ameliorate the prototyping risk. The performance of the plant since commissioning together with lessons for the future will also be presented.CITATION:Smith, R J, Kendall, W T C and Ngo, H D, 2013. Treatment plant innovation at Garden Well, in Proceedings World Gold 2013 , pp 315-324 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 26, 2013

By Alvin D. Cronberg

Silica flotation with amine salts has been a commercial process for years in certain non-sulfide mineral systems. Phosphate rock and feldspar deposits are notable examples. Generally, the quartz is clean and coarse. Primary amines and imidazolines are used, usually in a mole weight range 250-300, ad often fairly impure grades of collectors are satisfactory. As the production of magnetic iron concentrates grew in Michigan, Minnesota, Canada and in foreign locations, the iron mining companies began to explore amine flotation of silica to improve these concentrates. Many of the mining companies, as well as reagent suppliers, government laboratories and university research teams, had already studied amine collectors for silica, but the application to magnetic iron concentrates presented a real commercial opportunity to apply the art. Amine flotation of silica has been accomplished by simple addition of a flotation cell, and possibly a regrind mill, at the end of the magnetic concentration process. The flotation system gave the mill operator a flexible method to control final grade caused by ore variations in the feed. It increased iron content with lower silica, which resulted in lower freight costs per unit Fe and better pellets for blast furnace use.

Jan 1, 1968

By J. W. Chester

The rapid depletion of zinc-lead ore reserves and the rising costs of exploration have been major factors in the decline of mining activities and explorations for additional reserves in the Tri-State mining district. There is a need to develop new or adopt known, improved exploration techniques that will appreciably lower the costs of exploration. Demonstration of the practicability of using improved techniques to indicate, rapidly and cheaply, mineralized areas or geologic structures where more intensive explorations are justified could stimulate the search for and discovery of additional ore reserves. Various operators in the Tri-State district have used geophysical surveys to some extent since 1928 to guide exploratory drilling. Some geophysical investigations have also been made in the district by the State Geological Surveys of Kansas (11)3/ and Missouri (8, 13) and by Federal agencies (16), with the objective of directing exploratory drilling to areas where geologic conditions favored ore deposition. Many factual data obtained have not been published. The investigations generally have not been broad enough to permit conclusive evaluation of the usefulness of the geophysical techniques in all parts of the district.

Jan 1, 1959

By Fred C. Bond

Any improvement in the accuracy of commercial comminution calculations under the Third Theory must be accomplished either by increased precision in energy input measurements, or by a better evaluation of the total new crack length produced, as indicated by the feed and product size distributions. Since at the present time feed and product sizes are approximated solely by the microns 80% passes, the most promising opportunity for increased accuracy lies in consideration of their plotted size distribution characteristics. This paper shows how more accuracy can be obtained over an increased range of feed and product sizes from size distribution studies.

Jan 1, 1962

By Shengqin Zhang, Yousef Mohassab, Feng Chen, Hong Yong Sohn, Mohamed Elzohiery, Amr Abdelghany

A novel ironmaking process is under development at the University of Utah aimed at producing iron directly from iron oxide concentrate in a flash reactor. This process will reduce hazardous emissions and save energy. The kinetics of magnetite reduction with hydrogen was previously investigated in our laboratory in the temperature range 1150 to 1400 oC at large temperature increments (~100 oC increments). Due to the significant melting that occurs above 1350 oC, the reduction kinetics was measured and analyzed in two distinct temperature ranges of 1150 to 1350 oC and 1350 to 1600 oC (~50 oC increments). Experiments were performed using magnetite concentrate particles of different sizes under various hydrogen partial pressures and residence times. Reduction degrees of more than 90 % were achieved in a few seconds at temperatures as low as 1250 ºC. Different rate expressions were needed to obtain reliable agreement with experimental data.

Jan 1, 2016

CONTENTS PAGE Need for Research in Foundry Pig Iron. By Richard Moldenke. (With Discussion) 1 Carbon Characteristics of Copper-bearing Pig Iron. By W. B. Coleman. (With Discussion) 12 A Pig Iron, Low in Total Carbon, is in Demand for Use in Various Industries. By Enrique Touceda. (With Discussion) 24 Carbon in Pig Iron. By Ralph H. Sweetser. (With Discussion) 28 Second Session (Discussion) 37 Need for Research in Foundry Pig Iron BY RICHARD MOLDENKE,* WATCHUNG, N. J. So FAR as the quality of the product is concerned, the history of the production of pig iron for foundry purposes is one of constant retrogression. The steps in this deterioration began with cold-blast charcoal pig iron, then anthracite iron, coke iron; then gradually warm to hot-blast coke iron, with the charcoal furnaces also heating their blast to get greater tonnages, and finally the present-day hot-blast coke irons with scrap additions to the ordinary burden that, according to one European report, have gone as high as 65 per cent. Parallel with this quality retrogression is the enormous increase in furnace tonnages from about 15 to over 1000 tons per day in exceptional instances of modern practice. The key to this situation is economic pressure. The effect is a growing differentiation between furnace production for gray iron and malleable foundries and, for the

Jan 1, 1927

By M. C. Bétournay, J. E. Udd

"The Mining Laboratories of CANMET are the principal federal government vehicle for the delivery of mining research in Canada. With research being performed at five locations, which are mostly mining communities, the laboratories are in close proximity to the industry which they serve.The Mining Laboratories have three principal roles: (1) to support government in its development of policy; (2) to aid industry in the enhancement of productivity; and (3) to improve the health and safety of Canadians,both in the workplace in mines and around abandoned mine sites.From 1994 to 1996, CANMET’s mining research was re-focused into four programs. These are: (1) Underground Mine Environments; (2) Mine Mechanization and Automation; (3) Ground Control, and; (4) Coal Mining Health and Safety.In this paper, the authors outline the work of the Mining Laboratories and also identify the areas considered to be primary targets for future mining health and safety research in Canada."

Jan 1, 1997

By O. S. Tinkler, K. C. Sole

Approximately 20% of current world copper cathode output is produced using a hydrometallurgical process route, generally referred to as the leach–solvent extraction–electrowinning flowsheet. Since its commercialization in the late 1960s, steady improvements in the performance and efficiency of the solvent-extraction reagents and equipment, combined with significant developments in leaching and electrowinning, have made an ever-widening range of ore types amenable to this technology. Following successful implementation on all major continents, a large proportion of growth in recent years derives from the re-emergence of copper solvent extraction in the Central African Copperbelt. This review provides a brief history of the development and evolution of copper solvent extractants and mixer-settler contactors, and the significance of the Copperbelt region in achieving commercialization and acceptance of the technology. The opportunities and challenges presented by the abundant high-grade oxide ores of the Copperbelt are contrasted with the processing of solutions derived from the low-grade mixed oxide–sulfide ore bodies that are prevalent in other geological regions. The current status of hydrometallurgical copper production in the African Copperbelt, within a global context, and a medium-term outlook for the technology are discussed.

Jul 5, 2023

By Yu. E. Emelyanov, A. V. Bogorodsky, R. N. Nabiulin, S. V. Balikov

"The paper describes the results of the study of gold-copper flotation concentrate atmospheric oxidation at different sizes of material, varying oxidation time, with air or oxygen blow. The study showed the low rate of sulphide oxidation during oxidation of flotation concentrate at a feed size (P98 -74 µm). The coppery recovery into solution was 48%; the recovery of gold by subsequent cyanidation reached 86%. Preliminary flotation concentrate grinding to P98 -20 µm provided oxidation of 90% of copper minerals, 80% of arsenopyrite and 15% of pyrite. The gold recovery by atmospheric oxidation of a fine-ground flotation concentrate increased by 59%, from 36% to 95%, the NaCN consumption reduced by 21 kg/t, from 30 to 9 kg/t. INTRODUCTION Processing of sulphide gold-copper ores and concentrates using conventional cyanidation technology results in higher reagent consumption and lower gold recovery. Destruction of sulphide minerals and extraction of copper from a processed product prior to cyanidation is essential for improving efficiency of precious metals recovery and reducing main reagents consumption. Atmospheric oxidation (AO) is one of the most promising hydrometallurgical methods of refractory gold-copper concentrates processing, along with biooxidation and pressure oxidation. The nature of this approach lies in oxidation of sulphides at 90-95°C, in acidic or alkaline conditions, with bubbling of oxygen or air, after preliminary ultrafine grinding (1-4). The following reactions of sulphide oxidation occur during atmospheric oxidation of a gold-copper flotation concentrate. Pyrite is oxidized with the formation of ferric sulphate (1) and elemental sulphur at low temperatures (2), whereas some portion of elemental sulphur reacts to form sulphuric acid: FeS2+3,75O2+0,5H2O=0,5Fe2(SO4)3+0,5H2SO4; ?G=-1144,02 kJ/mol (1)"

Jan 1, 2018

By R. S. Dean

In the early days, most smelters were erected in nonarable land and at some distance from settled communities. The movement of population, which resulted in many instances from employment at the smelters, has brought to most smelterman in the United States the problem of preventing damage to plant and animal life in the territory adjacent to the smelters by sulphur dioxide gas (S02). This problem has been met, broadly, in two ways: (1) By diluting and removing the S02 by means of air currents and (2) by converting the S02 to a liquid or solid compound of sulphur and disposing of the compound.

Jan 1, 1937

By R. S. Dean

In the early days, most smelters were erected in nonarable land and at some distance from settled communities. The movement of population, which resulted in many instances from employment at the smelters, has brought to most smelterman in the United States the problem of preventing damage to plant and animal life in the territory adjacent to the smelters by sulphur dioxide gas (S02). This problem has been met, broadly, in two ways: (1) By diluting and removing the S02 by means of air currents and (2) by converting the S02 to a liquid or solid compound of sulphur and disposing of the compound.

Jan 1, 1937

By James M. Barker

Sulfur is a nonmetallic element of great physical and economic importance to the world. It is widely but sparingly distributed throughout the hydrosphere, lithosphere, and biosphere. Sulfur is the tenth most abundant element in the universe and eighth most abundant in the sun. In the earth's crust, which is mainly igneous, it ranks 14th, but is eighth or ninth in sediments (Kaplan, 1972; Stanton, 1972). It apparently is very abundant in the core of the earth, because it is a strong chalcophile, and it is fifth in abundance in stony and iron meteorites (Field, 1972) where it occurs as trolite (FeS). In ancient times sulfur was called brimstone, literally "burning stone." Today the term brimstone is used interchangeably with the term elemental sulfur. Shelton (1979) summarized most of the common definitions of terms, grades, and specifications for the sulfur industry as follows (with minor additions): Sources of Sulfur: Combined sulfur-Sulfur that occurs in nature combined with other elements. Cupriferous pyrites-Pyrite containing relatively minor amounts of copper sulfide minerals. Hydrogen sulfide-A toxic gas (H2S) occurring in natural gas and petroleum. Involuntary sulfur-Sulfur produced primarily as a result of legislative or process mandates. Native sulfur-Sulfur that occurs in nature in the elemental (uncombined) form. Nonferrous metal sulfides-Copper, lead, zinc, nickel, and molybdenum sulfides that are processed for their metal content. Organic sulfurs-Complex organic sulfur compounds occurring in petroleum, coal, oil shale, and tar sands. Pyrites-Iron sulfide minerals that include pyrite, marcasite, and pyrrhotite. Sulfate sulfurs-Sulfur in anhydrite and gypsum. Voluntary sulfur-Sulfur produced in response to market forces. Basic Sulfur Products Produced and Marketed: Acid sludge-Contaminated sulfuric acid usually returned to acid plants for reconstitution. Brimstone-Synonymous with crude sulfur. Bright sulfur-Crude sulfur free of discoloring impurities and bright yellow in color. Broken sulfur-Solid crude sulfur crushed to -8 in. Byproduct sulfuric acid--Sulfuric acid produced as a byproduct of a metallurgical or industrial process, generally relating to combined sulfur sources. Crude sulfur-Commercial nomenclature for elemental sulfur. Dark sulfur-Crude sulfur discolored by minor quantities of hydrocarbons ranging up to 0.3 % carbon content. Elemental sulfur-Processed sulfur in the elemental form produced from native sulfur or combined sulfur sources, generally with a minimum sulfur content of 99.5%. Formed sulfur-Elemental sulfur cast or pressed into particular shapes to enhance handling and to suppress dust generation and moisture retention. Frasch sulfur-Elemental sulfur produced from native sulfur sources by the Frasch mining process. Hydrogen sulfide-Associated with natural gas or petroleum and produced at refineries and coke oven plants; used to make sulfuric acid or recovered sulfur. Liquid sulfur-Synonymous with molten sulfur. Liquid sulfur dioxide-Purified sulfur dioxide compressed to the liquid phase. Molten sulfur-Crude sulfur in the molten phase.

Jan 1, 1983

By T. E. Green, E. F. Spano, W. J. Campbell

A combined ion exchange X- ray spectrographic method was evaluated for the determination of 11 metallic elements in high - purity tungsten : Aluminum , calcium , chromium , cobalt , copper , iron , magnesium , manganese , nickel , titanium , and zinc . Copper , nickel , and manganese in the 5- to 100 - microgram range ( 1 to 20 parts per million based on 5 - gram samples of tungsten ) , calcium in the 10- to 100 - microgram range , and cobalt in the 5- to 20 - microgram range can be determined within an accuracy of ± 10 percent of the amount present . Limits of detection of these elements are 0.05 to 0.14 microgram . The overall method was unsatisfactory for the determination of aluminum , chromium , iron , magnesium , titanium and zinc in tungsten .

Jan 1, 1964

By Shangyong Lin, Wei Sun, Weiping Liu, Muhammad Azam, Junfeng Chen, Yujie Zhao, David Asubonteng, Michael Ngoie

Copper concentrates are widely used in smelting operations worldwide and typically consist of chalcopyrite ( CuFeS2) as the primary mineral, with chalcocite ( Cu2S) and bornite ( Cu5FeS4) as secondary copper-bearing minerals. However, these concentrates often contain hazardous impurities, such as the fluorine ion, which can result in various complications during the smelting process. These issues include equipment corrosion, gas treatment requirements, environmental hazards, and strained community relations. Furthermore, high fluorine content in copper concentrates can lead to penalties and limitations during sales. To address these challenges, this comprehensive review assesses current techniques for removing fluorine from copper concentrate. Drawing upon recent research and the findings in the field, the review analyzes the advantages and disadvantages of existing fluorine removal methods and identifies critical issues requiring attention in the future. This review provides valuable insights into the current state of fluorine removal from copper concentrates and serves as a practical guide for researchers and industry professionals in this field.

Aug 2, 2023

By Zhanjing Yu

Longwall ground behavior in the Illinois Coal Basin was studied in the past (1, 2, 3). Most of the past studies, however, were concentrated on either surface subsidence or underground structural behavior. In this study, both surface and in-mine ground behaviors are considered, which include: 1) stress and deformation characteristics in the chain pillars; 2) roof and floor deformations; 3) surface subsidence characteristics, including time effect; 4) relationship between the surface subsidence and underground strata behavior; and 5) the ultimate hearing capacity underneath the chain pillars. Field measurements and tests were conducted and the data were analyzed using both analytical and statistical methods. The findings in this study can he used by mine operators in the Illinois Coal Basin for longwall ground control planning and design.

Jan 1, 1994

By L. M. Yokum

Tremendous strides have been made in front end loaders in the last 15 years. Fifteen years ago a 21/4-cu-yd front end loader was the largest standard machine you could purchase. Today there are two commercially available 15-yd front end loaders and many 10-yd loaders. The estimated total worldwide market for all front end loaders over 1 cu yd has increased to over 30,000 units yearly. The trend for front end loaders, in general, and for the mining market, in particular, is to larger and larger loaders. Today there are 18 and 24-cu-yd front end loaders in prototype form. It is not inconceivable that within another 15 years there will be front end loaders in the 50-cu-yd class with design features quite different from today's. These larger loaders are being designed at the demand of the mining industry, and the design criteria are being directed at this market area. The costs of these larger loaders may be greater per unit of capacity, but it is the intent of the various manufacturers that they will be more reliable, be easier to service, give greater availability, live longer, and cost less to maintain, than previous loaders. It is also the intent of the manufacturers to compete directly with the large mining shovel as the front end loaders become appropriately larger and more reliable. There has been some trend in this direction in the past with smaller shovels and loaders. In Table 1 are data for U.S. production of front end loaders (5 to 6-cu-yd class and 10-cu-yd class) and U.S. production of cable-operated, crawler-mounted power shovels, draglines, and cranes (11/z to 5-cu-yd class) for the years 1965 and 1970 (Source: Bureau of Census, U.S. Department of Commerce). Many believe that the decline in shovel production, in particular, is due at least in part to the acceptance of the front end loader as a primary production tool. However, the foregoing comparison is for a smaller shovel class than for front end loaders. It has generally been a rule of thumb that a front end loader is competitive on a cost and production basis with a shovel when it is approximately twice as large as the shovel. This same relationship may not hold true with the larger 10 to 15-cu-yd electric shovels, but at some point, direct competition will probably occur. Current Trends There are many trends today that are significant. One major usage trend in large front end loaders involves load and carry operations. This application is defined as "performing the functions of loading, hauling and dumping with one machine over distances within its economical limits." Many people are using front end loaders to transport material as well as load it. It is estimated that nearly half of all 10-cu-yd front end loaders sold in 1970 went into primary load and carry work. Many times, significant savings result from using the load and carry system, instead of small truck and shovel operations, for distances in excess of 1000 ft. Strip mining in coal utilizes great numbers of front end loaders in this manner. In-pit crushing of limestone is developing on an ever-increasing level, especially in Europe, and this stimulates interest in load and carry operations. In Table 2 is a cost example for 10-cu-yd front end loader in a limestone quarry. More than likely, load and carry use will continue to increase over the next few years. While some types of mining do not lend themselves to load and carry in the pit, such areas as surge piles are applicable and should be studied. In the area of machine operating cost reduction, there

Jan 1, 1974