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By Per Hedvall, Jan-Eric Ståhl

"The main objective of this study is to introduce the new Sandvik’s production cost-model within Crushing & Screening (C&S) technology. So far, there have been different ways of determining different production costs in the industry, however, the previously published and presented methods have not been very efficient in calculating the costs per product and metric ton. Accordingly, the current study has been planned and started in collaboration with Lund University to provide an accurate and easy to implement cost estimation program to determine the costs for crushing and screening plants worldwide.The proposed model has been adapted to fit the C&S processes of different rocks/ores fractions. The result is presented as cost per ton of the end product(s).Within this paper the cost estimation results for 3 different crushing and screening plants are presented based on the information obtained from the following sources: a) documents at Sandvik SRP, b) Sandvik’s crushing & screening internal/external machines/plants data and information, c) literature studies, including the use of Sandvik’s internal/external simulation and software programs, d), visiting the crushing and screening plants ,e) interviews, information systems’ data, and, f) testing and observations by ourselves.In order to improve the level of accuracy and the validity of the attained results, simplistic Monte-Carlo simulations have been used, where needed. The achieved results, so far, have proven the reliability of the model. The calculated cost estimations have shown an accuracy over 80% when they compared with real cost data obtained from plant practices.The current cost calculation model, will offer the possibility of:•,Calculating the production costs in proposed and/or existing C&S plant.•,Making detailed cost analyses for the end product(s) in proposed and/or existing C&S plants.•,Determining the profitability of each finished product when it’s required.•,Cost optimization by potentially cutting the cost for part of C&S plant with an existing plant practice"

Jan 1, 2016

By Joseph L. Ritchey

The Trail Lake RARE II area comprises 1,300 acres (526 ha) in Lassen and Plumas Counties, California, adjacent to the Caribou wilderness. No mining claims, prospects, or quarries are reported within the study areas, and no evidence of potential mineral deposits was found during a field reconnaissance. Quaternary basaltic lava flows uniformly underlie the area. INTRODUCTION The Trail Lake (No. B5-095) RARE II further planning area occupies 1,300 acres (526 ha) adjacent to the Caribou Wilderness in Lassen and Plumas Counties, California. Susanville is about 30 mi (50 km) east and Chester is about 17 mi (27 km) south of the study area. Access from State Highways 44 and 36 is provided by well-maintained gravel roads.

Jan 1, 1981

By H. P. Greenwald

[In many coal-mining countries, during he pest decade, there have been made extended studies and accurate measurement of movement of roof strata, tests of the physical properties of specimens cut therefrom, and tests of the strength of end load on artificial supports. Naturally, such studies have been more extensive in European countries, where mining conditions are less favorable than in the United States. As a part of its work in the conservation of coal resource and prevention of accidents in mints, the Bureau of Mines began systematic measurement of the movement of roof strata to in coal mines in the fall of 1935. It was decided that, in the beginning, work on a rapidly retreating rib line in a mechanized mine would give the greatest amount of information in a reasonable time. To this end a cooperative agreement was made with the Pittsburgh Coal Co., Dr. L. E. Young, vice president in charge of operations, for conduct of work in that company's Montour 10 mine operating in the Pittsburgh coal bed, This paper gives an account of the methods used in the investigation, excerpts from the date obtained, and such generalizations as appear to be justified.]

Jan 1, 1937

By Lawrence Pelham

Introduction Fluorspar demand or consumption has been taken for granted in recent years, except for those that produce, market, or consume the commodity. Thinking used to be that as the steel and aluminum industry goes, so goes fluorspar. This is much less true today. The industry is becoming more dependent on chemical industries that feed primarily off hydrofluoric acid (HF) production. The US Bureau of Mines (USBM) published an assessment of world fluorspar reserves and resources. It created a foundation of valuable data that can be used to monitor fluorspar availability. Celebrations were held this year commemorating the 100th anniversary of the isolation of fluorine. The US and other countries continue to struggle with the controversy of ozone depletion and the effect of fluorocarbons on the atmosphere. Goals for the government's strategic stockpile are being reevaluated. The market for fluorine chemicals is changing and diversifying, making it a challenge to assess and forecast fluorspar/fluorine demand. US production and distribution Fluorspar Fluorspar shipments from US mines reached an all-time high near the end of World War II in 1944 at 375 kt (413,800 st). Eighty-two mines produced more than 453 t (500 st) each, and 10 mines produced more than 9 kt (10,000 st.) each. Illinois supplied 43% of total shipments. Consumption in 1944 was 372 kt (410,200 st), of which 56% was used by steel producers and 32% by HF producers. This was the last year that US production exceeded US consumption. The post-World War II record for fluorspar shipments occurred in 1951 at 315 kt (347,000 st) 58 mines produced more than 453 t (500 st) and eight mines produced more than 9 kt (10,000 st).

Jan 11, 1986

[NORTH AMERICA UNITED STATES ALABAMA Birmingham Cord, Richard H. Dlsmukes, Edward B. Hunter, Robert A. Citronelle Perrin, Huey P. Fairfield Pagel, Herbert Ervin Fairhope Ruffles, William R. Huntsville Eng, Harvard Kelley, Dean W. Waggoner, J. B. Weber, Thomas C. Mobile Hankins, James D. Horner, William L. Petroutson, Peter C. University Cudworth, James R. Jones, Walter B. Mason, William L.]

Jan 1, 1961

By Karl J. C. Harries

"3.1. INTRODUCTIONThis chapter discusses briefly the common law concepts of fiduciary relationship, constructive trust, and breach of confidence. Following a discussion of confidentiality agreements, the last section of the chapter compares and comments on two common law cases, the LAC Case and the Metalore Case. Civil law readers should not ignore this chapter or § 3.5. the comparison as, to a large extent, the concepts and comments are universal, even though the procedures for applying them may vary.1It should be appreciated that, regardless of the legal system, if the Court sees that a wrong has been done, it will attempt to right that wrong, either by awarding monetary damages against the wrong-doer to compensate the injured party or by attempting to make the injured party whole again by such means as negating an agreement (as in the Metalore Case) or returning property to a wronged party (as in the LAC Case). The methodology for accomplishing either of these results will vary with the jurisdiction, and the two are not mutually exclusive.These two Ontario cases have been chosen, not because they are the only ones available – they certainly are not – but because both are relatively well known within the minerals industry and they deal with problems that may face any explorationist (although it is to be hoped that the facts of the Metalore Case do not represent “normal” behaviour). Each judgment offers useful guidelines, as well as insight into a judge’s approach to problems, the type of information he expects to receive, how his mind works, and, particularly in the Court of Appeal judgment in the Metalore Case, how he might reason through and “justify” his decisions.3.2. SOME LEGAL CONCEPTS In order to appreciate some of the matters discussed in this chapter, it is necessary to have some idea of the common law considerations of fiduciary relationships, constructive trust, and breach of confidence."

Jan 1, 2003

By P. A. Plunkert, D. E. Morse, L. McCartan, J. F. Papp

The mineral sector is a fundamental part of the U.S. economy. It contributes to the real gross domestic product (GDP) at several levels — basic (mining), intermediate processing, manufacturing of finished goods and construction. The real GDP during 2004 increased by 4.4 percent. The nominal GDP was about $11.7 trillion. Housing starts were up by slightly more than 4 percent for the year. And the nation’s unemployment rate decreased to5.5 percent in 2004 from 6 percent in 2003. Interest rates continued to be low (prime rate was 5.25 percent at the end of 2004) but have risen gradually, following rising inflation.

Jan 1, 2005

By H. Antrekowitsch

The decreasing quality of the input materials in copper recycling leads to a higher content of impurities in the anode copper. An improvement of the pyrometallurgical refining process is therefore necessary to produce high quality anodes for the copper refining electrolysis. The behaviour of the most important accompanying elements (e.g. nickel, tin, lead, zinc etc.) at different reaction conditions has to be investigated in order to improve the metal/slag reactions as well as the vaporisation by selective oxidation in the anode furnace. Therefore the thermodynamic conditions like reaction order and the activity coefficients at the copper refining process have to be known for the optimisation of this technique. Additionally the interaction between different elements has been investigated as a function of the temperature, the content of the elements and the slag composition especially for nickel. These investigations were done at the Christian Doppler Laboratory for Secondary Metallurgy of Nonferrous Metals.

Jan 1, 2005

By David Humphreys

It is difficult to overstate the importance of China to the future of the world mining and metals industries. In a remarkably short time, China has risen to become the world?s largest producer and consumer of steel and its second largest consumer of non-ferrous metals such as copper and aluminium. It is currently the world?s largest buyer of copper on international markets, the second largest buyer of iron ore, and the third largest buyer of alumina. At the same time, it is the world?s largest or second largest producer and exporter of tin, lead, zinc, magnesium and a host of minor metals and industrial minerals, as well as a fast-growing exporter of coal.

May 1, 2002

By C. H. Stockwell

THE Eastern Townships of Quebec have been the chief Canadian source of chromite. Production, however, has never been large and, except for a period of steady but small output between 1894 and 1909, mining has been active only in war time. The known deposits are too small or too low grade to compete with overseas sources in normal times. During the last war, shipping difficulties and a greatly increased demand in the United States resulted in high prices and a ready market for low-.grade material. The Quebec chromite industry flourished and played an important part in relieving the wartime shortage. Shipments in 1918 .amounted to 15,600 tons of crude ore and 6,400 tons of concentrates. At the outbreak of the present war it was natural to turn again to the Quebec field as a possible source of this strategic mineral. Some of the old properties have since been opened by private and government money and some new deposits have been found. Total mill capacity is 750 tons per day, as compared with 200 to 300 tons in 1918. During 1940, 1941, and 1942, about 85 chromite deposits were examined by the Geological Survey in a belt 100 miles long and up to 7 miles wide. A part of this belt, about 35 miles long, in which the geological features ?were not well known, was mapped on a scale of 1/2; mile to an inch.? Small ..areas around some of the deposits were mapped in detail, on scales of 20 to 200 feet to an inch. Some geophysical work was done but did not result in the discovery of ore. Prospecting by stripping and trenching was then undertaken and chromite ore was uncovered at several localities. The above work was done by the writer and by J. W. Ambrose, who has kindly contributed his results for incorporation in this paper. Y. O. Fortier actd as assistant in the geological work and, in 1942, was in charge of a sub-party engaged in geological mapping. The author is indebted to H. C. Cooke and J. W. Ambrose for reading the original manuscript and for offering many helpful suggestions for its improvement.

Jan 1, 1944

By A. Moskowitz, L. S. Redmerski

The corrosion resistance of stainless steels can be strongly affected by surface treatments. Changes in corrosion resistance can relate to surface composition, integrity and stability of the passive film, and to surface profile (roughness). Operations producing oxidation at the surface, such as annealing, heat treating, and welding, can result in a chromium-rich scale and a chromium-depleted metal surface. In order to restore full corrosion resistance, chemical or mechanical clean-up techniques must remove not only the oxide, but also a very thin layer of metal. Laboratory and field test studies show that these factors are particularly significant in less highly alloyed steels. Annealing stainless in a reducing atmosphere (bright annealing) avoids chromium depletion, but as-bright-annealed material does not display optimum corrosion resistance in certain environments. Electro passiva-tion can be applied to improve pitting resistance without significantly changing bright surface appearance. Potentiometric studies show that electropassivated material also displays significantly greater resistance to breakdown of passivity in acid solutions. The application of special surface finishes for appearance purposes can affect corrosion resistance. Roughness is a key factor. Samples of related appearance but with different surface profiles can show significant differences in corrosion resistance. Thus nonreflec-tive stainless with a relatively smooth surface produced by a special rolling process is much superior to material chemically etched to a similar low reflectivity. THE corrosion resistance of a stainless steel is affected by other factors in addition to its bulk composition and metallurgical structure. These other factors include those relating to the specific chemical and physical condition of the steel's surface. This paper will consider certain aspects of surface condition in relation to corrosion resistance. In particular, studies will be described on the effects of oxidation encountered in heat treating or welding operations, of passivation after bright annealing, and of different surface finishes. EFFECTS DUE TO OXIDATION When stainless steels are exposed to high temperature in an oxidizing environment, as in annealing or welding, the oxides formed are relatively rich in chromium. As a consequence of oxidation, the metallic layer directly beneath the scale may be low in chromium to some very thin but finite depth.1"8 Such a change in chromium content could lower the corrosion resistance at the surface, whether or not the oxide layer is removed. Studies were performed relating to the effect of oxidation and chromium depletion produced during annealing and welding on the corrosion resistance of stainless steels. The nominal compositions of steels used in this study and others are given in Table I. A) Annealing Studies on 17 pet Cr Steels. 1) Effects of Pickling Treatments. Studies were performed to investigate the corrosion resistance of air annealed type 430 stainless as a function of the amount of electrolytic pickling after annealing. The material used in this study had been air annealed and electrolytically pickled in the mill. All scale had been removed, and yet the material showed unusually poor corrosion resistance. Laboratory electrolytic pickling studies were performed to determine whether additional metal removal from the surface would improve corrosion resistance. Electrolytic pickling was performed in a sulfuric acid bath using various conditions of bath acidity, temperature, time, and current density. The samples were then rated for corrosion resistance in a ferric chloride spot test. For this spot test, a solution was prepared by dissolving 10 g of FeCl3 . 6H2O, 5 g of NaCl, and 2.5 ml of concentrated HC1 in 200 ml of water. An area on a specimen was cleaned and a drop of test solution was placed on the prepared area. After 5 min, the drop was rinsed off and the area wiped dry. The spot was then rated between 1 and 5 by visual comparison with standard spots. The numerical rating of the standard spots can be described as follows: 1—No clouding of surface; 2—very slight clouding of surface; 3—slight clouding of surface; 4—moderate clouding of surface; 5—strong clouding of surface. A rating of 1 or 2 was considered to have passed the test, a rating of 4 or 5 represented failure, and a rating of 3 was considered borderline. The severity of etching in this test has been related to the actual chromium content at the surface.4 Etching (clouding) occurs on type 430 stainless (rating of 4 to 5) when the surface chromium content is 14 pct or less. The effects of current density and retention time when electrolytically repickling this material in 6 pct sulfuric acid are shown in Fig. 1. Increasing the cur-rent density or retention time improved corrosion resistance as measured by the spot test. Similarly, increasing acid concentration of the bath or bath tem-perature was found to improve corrosion resistance. The conditions making for improved spot ratings resulted in increased metal removal, regardless of specific pickling conditions used, Fig. 2.

Jan 1, 1970

By N. W. Hendry

ABSTRACT Exploration by geophysical methods and diamond drilling of an occurrence of chrysotile asbestos, located ten miles east of Matheson, Ontario, was commenced on March 25th, 1949, by the Canadian Johns-Manville Company, Limited. The asbestos is associated with a narrow sill-like body of basic and ultrabasic rocks which strikes northwesterly across portions of Munro and Beatty townships. To date, asbestos zones of commercial interest, many hundreds of feet in length, width, and depth, have been outlined by diamond drilling along a 2-mile length of serpentine. The fractures occupied by the asbestos veins are closely associated with the regional faulting in the area. The mining of the first occurrence, or A orebody, will be by open-pit methods. Milling will commence at a rate of 50 tons an hour. INTRODUCTION OCCURRENCES of chrysotile asbestos in Munro township have been known at least since 1914 and references to them appear in reports published by the Ontario Department of Mines in 1915 (1) and 1919 (2). J. G. Ross (3) in his excellent publication on Chrysotile Asbestos in Canada, mentions an occurrence in Munro township. The area was first mapped in detail by J. Satterly, of the Ontario Department of Mines, in 1944, and brief mention is made of chrysotile asbestos in Satterly's preliminary report (4), which was published the following year.

Jan 1, 1951

Experiment of Improving the Quality and Decreasing the Impurity of Titanium Concentrate in Panzhihua Mine in China

Sep 13, 2010

By Thomas T., Read

ANY discussion of State-supported schools of mining and A metallurgy needs to be prefaced by a definition, since the first school to offer a mining curriculum, the Pennsylvania Polytechnic College, was established by a grant from the State. But, so far as can be determined, it received no further State support. It would be tiresome to go into precise details,. and it will be enough to stipulate that by State schools are meant those which derive their main financial support from regular appropriations made by a State legislature. The University of Michigan was the first of these to offer a mineral industry curriculum; its story, as well as those of Wisconsin and Illinois, has been related in the preceding chapter.* Arranging the others in chronological order involves making a decision as to what weight to attach to plans for giving instruction, as contrasted with its , effective initiation. This may appropriately be illustrated by the history of mineral industry education in California. California Among those who came to California in 1849 and the following years were many New Englanders who had a keen interest in education. Some of them, mostly Congregationalists and Presbyterians, sought to establish a school of higher education around San Francisco Bay and eventually succeeded in opening the "Scientific and Classical School at Contra Costa' in Oakland, at Broadway and 5th St., on June 20, 1853. This prospered so well that it was chartered by the State as the "College of California" on April, 13, 1855. Developing so rapidly that its quarters became cramped, in 1864 it not only bought a tract of

Jan 1, 1941

By Frank R. Field, Randolph E. Kirchain, Elisa Alonso

"There are a number of environmental incentives for increasing recycling, including the reduction of waste, energy and resource use. Recycling can also be advantageous for manufacturing firms in both the short and long term. Secondary material can substitute for primary material, potentially dampening primary material price increases and reducing the pressure for greater primary extraction. This paper examines the potential for and dynamics of recycling for the case of platinum using a dynamic, behavioral simulation model of the primary and secondary markets. Since the secondary supply of platinum depends on a supply chain separate from primary extraction, recycling can diversify the risks of primary supply instabilities. Over time, recycling can cut primary consumption, reduce overall costs to firms, and possibly reduce the impact of price fluctuations upon firms.IntroductionThe benefits of recycling, from the perspective of the environment, are many, and the environmental benefits of increased recycling are considered a step towards increased sustainability [1, 2]. Life cycle assessments indicate that obtaining materials from secondary sources generally requires less energy and has fewer environmental impacts than extraction and refining of primary materials [3]. Analyses of materials flows show that, in addition to landfill volume reduction, recycling reduces primary material consumption, affecting long term materials scarcity [4, 5].The benefits of recycling are not limited to the environmental. Firms can benefit from the lower energy costs of recycling, especially that of metals whose primary extraction and refining are particularly energy-intensive (e.g., aluminum). The routine participation by firms in secondary materials markets (e.g., www.recycle.net) shows that this advantage has not gone unnoticed.Recycling can also benefit firms whose costs can be significantly affected by changes in material prices resulting from material shortages and material scarcity, with potentially permanent effects upon firms [6-8]. This paper focuses on the impact of recycling in the face of platinum scarcity for supply chain downstream firms."

Jan 1, 2008

By Joseph J. Wallace, William H. Tavenner, D. A. Reynolds, John M. Provost, James J. Dowd, R. F. Abemethy

"CONCLUSIONSThe investigation shows that there are 5 coal beds of major importance in Wyoming County from the standpoint of present production - Pocahontas No. 3, No. 2 Gas, Sewell, Beckley, and Eagle - and 5 beds of minor importance - Pocahontas No. 6, Cedar Grove, Winifrede, Douglas, and Chilton. The Pocahontas No. 3 bed contains the largest remaining known reserves.Known measured and indicated reserves in all beds, based on a minimum thick¬ness of 14 inches and on 1,800 tons per acre-foot of coal in place, are estimated at 2,665 million short tons as of January 1, 1951. Of this total, 2,121 million short tons is in beds 28 inches and more thick. Areas in each bed were omitted from the estimate because available data relative to the bed characteristics are too meager to make an estimate that conforms with the definitions of measured and indicated coal adopted for this study. Should future drilling or development prove reserves in these areas, such reserves should be added to the total estimated reserves.Recoverable reserves of coal have been estimated in beds 28 inches and more thick. This thickness is about the minimum now being mined by hand loading onto conveyors in the Appalachian region. The weighted average recovery for all beds in Wyoming County, as determined by this investigation, is 55.0 percent. This percent¬age is based on the total thickness of coal (less partings 3/8 inch or more thick) in the bed rather than on the thickness of the coal mined. The known recoverable reserves are estimated to be 1,167 million tons as of January 1, 1951.4. Since most of the Wyoming coals are medium- and low-volatile bituminous in rank and expand during carbonization in modern ovens, they are blended with high-volatile contracting coals."

Apr 1, 1953

By M. E. Huckman

In this paper, we review the equations needed to construct an ion exchange column model. These models contain three major components: 1) a differential material balance around the colunm, 2) a differential material balance around an ion exchange particle, and 3) a constitutive equation for diffusive flux We then examine the ability of a fairly simple mathematical model to predict ion exchange column experimental data. This model contains the traditional absorption theory equations and is used to predict the behavior of a column filled with a hydrous crystalline silico-titanate and which is removing trace amounts of Cs+ from a high pH, complex electrolyte solution. Finally, we propose replacing Fick's law with the Nernst-Planck equation as the constitutive equation for diffusive flux We use a Nernst-Planck type model to predict batch experimental data, then evaluate it by comparing it's ability to predict experimental data to that of a more traditional Fick's law type model? The data from this comparison suggests that the Nemst-Planck type model yields better results.

Jan 1, 1996

Interest in mining narrow, vein-type ones has increased world-wide during the last few years despite the fact that prices of metals have not risen in proportion as production costs of mining, such as labour and energy. In many mines, where narrow ones are mined, the mining technique and equipment used have been poorly mechanised. The mining methods have been cut-and-fill or shrinkage stoping. Pneumatic jack-legs have been used for drilling and slushers have been used for loading. The methods that have been used can be called the 'first-generation' methods. Work has been very hard for miners. It has been dangerous and exhausting. Production volumes of mines, and a s a result of that, also profits have been low.

Jan 1, 1990

By José Arce

El sistema AG-DAS entró en operaciones en 2015 y su aplicación tiene diversas ventajas sobre el método de polarización inducida convencional. El concepto del sistema fue el uso de múltiples receptores de dos canales, que registran la señal completa con sincronización de tiempo por GPS. La tecnología DAS (sistemas de configuración distribuida, por sus siglas en inglés) brinda mayor confiabilidad en la detección y modelamiento tridimensional de mineralización metálica con geometría compleja a profundidades de hasta más de 800 metros.

May 22, 2019

By Albert J. McIntosh

With petroleum consumption declining temporarily after V-J day, the oil industry is urged to use this period as a kind of stopgap to rebuild its war-depleted inventories and help cushion the effect of this decline on producers and refiners. Higher inventories should be reestablished, since recent experiences have indicated that, by and large, the present inventories of crude oil are too low even with the tremendous current production available. The following analysis indicates that inventory levels could be built up to about 490,000,000 bbl. by the end of 1947, an increase of about 40,000,000 bbl. over the reported stock estimated for the war's end. If at the end of the war the military have some 20,000,000 bbl. on hand, this inventory will either be resold to the industry or certain demands that have been assumed to be met by industry will be supplied out of these military stocks, which would leave about 20,000,000 bbl. (net) to be built up from current production. For stock rebuilding the industry could use 10,000,000 bbl. of crude plus 10,00,000 bbl. of products, totaling 20,000,000 bbl. If this were spread over a year, this would mean 55,000 bbl. a day. By analyzing the average inventories held in a year with the total quantity of goods handled during the year, the following study and tables indicate how far the inventories should increase in the immediate postwar period. Introduction For the period immediately following V-J day, most of the petroleum economists have forecast a considerable decline in the total consumption of petroleum and its products in the United States. This will be caused by the elimination of most of the military demands and the inability of civilians to immediately replace automobiles, burners, etc., and thus increase their requirements to make up for the military decline. When the automobile industry has been back on full production for two or three years, civilians will be able to consume much larger quantities of gasoline. Delay in the manufacture of new oil burners and the time it takes to construct new homes, adds up to the same story for distillate fuels. In reviewing this outlook, the question has arisen whether the petroleum industry should not use this period of lower consumption as a kind of stopgap to rebuild its war-depleted inveritories and help cushion the effect on producers and refiners of this sudden drop in requirements. Some persons have indicated that hundreds of thousands of barrels a day could be used for this purpose extending over a year or more. Refineries will be in existence, which could run over 5,000,000 bbl. of crude oil a day and crude-oil production might be running 600,000 to 700,000 bbl. a day above the demands now forecast for the period after V-J day. Reasons for. Making Inventories In order to plan intelligently for this period, the petroleum industry should determine the needs for the establishment of higher inventories for crude and petroleum products than have been carried during the war. The reasons for trying to make such a determination are as follows:

Jan 1, 1945