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Properties of coal which are significant in relation to preparation for carbonization and conversion are reviewed, and existing coal preparation technology which has been used for production of cleaned coal of suitable ash content and petrographic composition for carbonisation, pyrolysis, hydrogenation and similar processes is described. Possibilities for application of this technology to some Australian coal seams is examined briefly. It is concluded that further survey work is required related to the optimization of selective crushing and concentrating operations, with the aim of maximizing production of quality products for carbonisation, etc mainly from Australian seams with only moderate coking characteristics.

Jan 1, 1980

By F. H. Abd EL-Rahiem

A selective dispersion process is presented and the work carried out to find optimum process conditions to minimise the colouring material in ground calcium carbonate (GCC) is described. The feed material is the overflow product from a hydrocyclone which results from using a Denver Attritioning machine with semi-autogenous grinding for one hour and a 1:1 ore/water ratio. By using sodium silicate (SS), with pH 9 and pulp density 5%, the iron content (as colouring impurities) is decreased from 0.21% in the original concentrate to 0.12% in the final concentrate. The degree of whiteness reached is improved to 85% from 63% in the original material. However, by using hexametaphosphate (SHMP) at pH 10 at the same pulp density, the iron content decreased to about 0.073% and hence the whiteness degree increased to about 96%.

Jan 1, 2004

By Melford H. Salsbury

The maximum net return from the sale of ores and concentrates of gold, silver, copper, lead, and zinc accrues to the producer when these mine products are marketed to the best advantage. Data are presented that the producer, especially the small mine operator, can use to survey available markets and make a preliminary estimate of the net return to be expected from an ore, on the basis of typical mill, smelter, and freight schedules. A review of the industry is presented by States in which recent production statistics are given, marketing facilities are discussed, and locations of principal mining districts, custom mills, and smelters are shown. Explanations of treatment processes, ore types, treatment charges, payments for metals, and deductions are given. Published rail and truck freight rates for mine products, based on marketing patterns developed over many years, are listed and explained.

Jan 1, 1964

By Kenneth H. Johnston

This report describes in detail three waterflooding projects and a pressure-maintenance project in Butler and Cowley Counties, Kans., that will be visited on the 1963 annual spring tour of the Kansas-Oklahoma Waterflood Association. Among the unique features of the projects are the flooding of five oil-producing horizons separately with injection water furnished by two water-treating plants. Discussion of the individual projects includes information on their early history, the source and treatment of the injection fluids, oil production decline curves, and the results of water injection on oil production.

Jan 1, 1963

By Daniel G. DiCanio

This report describes a computer-based model for estimating the tangible costs of injuries and deaths from work-related accidents in underground coal mines. The study undertook to identify and quantify the elements of accident costs, including field visits to coal mines, insurance carriers, and public agencies. The mathematical models developed for each tangible element of accident cost are presented in Volume I of the report. A listing of the computer programs which comprise the model and instructions for using the programs are presented in Volume II. Statistical distributions of mining family characteristics, data on 95 miners killed in underground accidents, and other basic data used to develop the model are presented in Volume III. Application of the model to a data base of 9,286 accidents which occured in underground bituminous coal mines during 1974 yielded a total of $56,900,000 in tangible costs to industry, mining families, and public agencies. Loss of income to the families of miners injured or killed in these accidents accounted for 47 percent of the total.

Jan 1, 1976

By Tellis D. A

An outline is given of the general position of earthsciences information in Australia, the background to development of the Australian Earth Sciences Information System (AESIS) and the role of the Australian Mineral Foundation in developing and co-ordinating the projeot in co-operation with the CSIRO, BMR, National Library of Australia, AGIA, and many companies.Details 'of the system, method and anticipated rate of input (especially of unpublished material at which the System particularly aims), mode of dissemination, and use of the data base are discussed. Information on theAustralian Thesaurus of Earth Sciences and Related Terms and brief details of some 30 earth sciences information collections in Australia is given.

Jan 1, 1977

By G. R. Peterson

To determine the availability of lead and zinc from demonstrated resources, the Bureau of Mines evaluated 235 mines and deposits in 31 market economy countries. Of the 235 mines and deposits evaluated for this study, 186 were evaluated as zinc operations, 30 as lead operations, and 19 as copper operations. Demonstrated lead-zinc resources of market economy countries in 1981 were approximately 4.3 billion metric tons (t) of ore containing 221 million t of zinc and 97 million t of lead. Of these amounts, approximately 154 million t of zinc and 70 million t of lead are estimated to be recoverable. The analyses indicate that demonstrated resources in market economy countries should be sufficient to satisfy projected demand for primary lead and zinc through the balance of the century. The U.S. lead industry will continue to have a comparative advantage over the rest of the world industry, barring any drastic increase in the cost of compliance with pollution control regulations. It appears that the comparative disadvantage faced by the U.S. zinc industry will probably intensify owing to the relative quantity of lower cost zinc resources in other countries, especially Canada, Australia, Mexico, and Peru.

Jan 1, 1985

By Adil Aledresse, Louis Mercier, Laxman Amaratunga

"The development of high capacity adsorbents with uniform porosity denoted, MP-HMS (Mercaptopropyl – Hexagonal Mesoporous Structure) using nanotechnology, and their ability to extract gold from solution, is presented. The preparation of highly effective heavy metal ion adsorbents by the incorporation of thiol moieties into the pore channels of mesoporous silica molecular sieves has been the subject of many nanotechnology research investigations. The unique feature of these nanoporous adsorbents is their ability to adsorb gold ions from ultra-low concentration solutions like mine effluent as well as from leached solutions in gold mills. The preliminary studies from laboratory simulated gold solutions show that the adsorption capacities of these materials are also among the highest reported. MP-HMS has shown the capability to adsorb 370 mg gold per one gram of the nanomaterials from Tetrachloroaurate solution (up to 37% of their weight). Experimental studies indicated that the maximum adsorption of gold (as high as 99.9% recovery). The current studies will be extended to investigate the interaction of ionic gold complexes with nanomaterials. Future development of this work may lead to either to replace the conventional CIP/CIL processes or use nanomaterials in tandem with the former, suggesting plausible use of mesoporous material in pulp, MIP or in leach, MIL, as a novel gold extraction process.INTRODUCTIONGold typically occurs at very low concentrations in ores less than 10 g/t or 0.001% (mass basis). At these concentrations the use of aqueous chemical (hydrometallurgical) extraction processes is the only economically viable method of extracting the gold from the ore. Typical hydrometallurgical gold recovery involves a leaching step followed by the separation of the gold bearing solution from the residues, or adsorption of the gold onto activated carbon adsorbent. After elution from the activated carbon the gold is further concentrated by precipitation or electrodeposition."

Jan 1, 2008

The project to reopen the Tasmania Mine has centred around efforts to reopen the Hart Shaft to access the high grade reef remaining below the old workings, which extend down to 457 in. Efforts in 1982 and 1987 were frustrated by unstable clay ground around the shaft, which resulted in significant subsidence of the shaft collar and lining. A successful program has since been implemented to solve the problems, stabilize the collar and recover the upper shaft which had collapsed down to 90 m.

Jan 1, 1989

By S. H. Lorain

This paper is a preliminary report on recent lode gold mining activity, operating conditions, and mining and milling methods at properties in production in September 1936 in the gold belt of northeastern Oregon. A few inactive properties are described also. Districts, inactive in 1936, that have been important producers at some time in the past are mentioned briefly. This is one of a series of similar papers describing western mining districts. The past production record of the gold mines of northeastern Oregon entitles the region to be ranked as one of the important gold-mining regions of the United States. Although comparatively inactive for many years, lode mining in the region has recently undergone a marked revival.

Jan 1, 1938

Close spatial relationships between the deposits of the Etheridge Goldfield (23 000 kg of bullion) and various regional geological and geophysical features suggest that genesis of the ore deposits was a multi-stage process that started with magmatic and metamorphic stages in the mid-Proterozoic, climaxed with structural and hydrothermal stages in the late Palaeozoic and terminated with an oxidation enrichment stage in the Cainozoic.This hypothesis permits classification of the Georgetown region into areas likely to contain deposits of the Etheridge type and those unlikely to do so; it is concluded that there is little scope for the discovery of extensions of this field.However, the stratigraphic interval between the postulated source rocks of the Etheridge field and stratigraphically higher host rocks of the Croydon field may contain disseminated replacement gold deposits of the Carlin type. The potential host (Pyritic carbonaceous, and locally dolomitic siltstone of the Candlow Formation) is locally faulted and cut by granitoids and the extension of a mineralised, long-standing zone of structural weakness.

Jan 1, 1981

By D. N. Dietz

Jan 1, 1969

By Tim O’Neil

The search for precious metals opened up the American West. And Nevada was right in the heart of this development. In the mid-19th century, prospectors seeking gold roamed the hills of Nevada and discovered the ComstockLode. The development of this huge silver and gold deposit began in1859 and was responsible for Nevada’s early entry to statehood. Mining was Nevada’s first industry. In more recent years, the Nevada mining industry has led the nation in gold, silver and barite production. Nevada also produces many other minerals. These include aggregates, clays, copper, diatomite, dolomite, gypsum, lime and limestone, lithium and magnesium compounds, perlite, salt and silica. Even today, Nevada’s mining industry continues to be a major economic force in the state. The mining industry has made more than $10 billion in capital investments in Nevada since 1985. And the value of Nevada’s mineral production last year was about $2.7 billion.

Jan 1, 2000

The Hill 50 Gold Mine is situated at Boogardie, 3 miles on a bearing of 295 degrees from; Mount Magnet township. Mount Magnet lies 300 miles north-north-east of Perth, Western Australia (Fig. 1).The older workings of the mine may be identified with those of Sirdar, Gold Mining Lease 696M The Sirdar had been worked before 1902 though no records remain, and irom 1903 to 1912 about a thousana tons at a grade of 6' 2 dwt. was extracted annually; by the end of 1918 6,225 oz. of gold had been obtained from the milling of 17,852 tons of ore. In view of these yields, and the length and width of the lode, this mine was early recognized as one of the most promising in the district. From 1919 to 1924 the ground,including G.M.L. 1282M, was held as Mt. Zion G.M.L. 1183M.The Hill 50 Gold Mine N.L. company took up the workings as Hill 50 G.M.L. 1282M in 1934 and have continued operations to the date of writing. To the end of 1956 the Hill 50 Gold Mine had yielded 982,106 tons of ore for a return of 448,'602 fine oz. of gold.The mine has been described by: J utson (1915), Feldtmann (1920), Johnson (1949), and Finucane (1953). Finucane (1953) details the mine structure to a depth of 414 ft. The author was able to examine the mine to a depth of 1305 ft. Detailed main level mapping to the 1060 level and a detailed surface examination have revealed aspects of the structure which were previously obscure.

Jan 1, 1960

By H. Saroglou

Anisotropy is a characteristic of intact foliated metamorphic rocks (slates, gneisses, phyllites, schists). Testing was used to establish the anisotropic behaviour of selected gneissic rocks. The effect of anisotropy on various mechanical properties (strength, deformation) and dynamic properties (wave velocity) was examined. The rock samples were also tested at successively higher confining pressures in order to evaluate the effect of anisotropic behaviour at high overburden pressures.

Jan 1, 2004

By Maarten van de Vijfeijken, Marco Rufli

"By using the latest generation of medium voltage frequency converters, new possibilities have arisen to improve the grinding process. Beside all the direct and indirect advantages, several dedicated functions have now been implemented for ring geared grinding mills in the minerals industry. The advanced operational functions ensure a smooth, safe and reliable operation with minimum stress for the mechanical equipment and therefore highest availability of the mill. Several papers have already been presented concerning the benefits of using this state of the art technology for mill drives (Ravani von Ow and Bomvisinho, 2010; Ravani von Ow and Gerhard, 2010). However this paper will not only show and explain the operational benefit of these functions, but will focus on the experiences gained with this kind of sophisticated ring geared mill drive system. Several measurements of different operating conditions (starting, frozen charge remover, controlled roll back, backlash, etc.) made on an installed and commissioned 2 x 5 MW dual pinion ring geared mill drive system will be shown and discussed. Also the accuracy of the load sharing between the two 5 MW motors during starting, normal operation and stopping will be demonstrated using real measurements from an operating system. Finally the inherent features of these drive systems are briefly discussed.INTRODUCTIONLooking at the demands of grinding mills, we can split them into operational, maintenance and protective demands. For smooth and safe operation, it is important that critical situations are avoided as much as possible. Maintenance functionality must be quick and easy to execute, while protection of the system is important during all operating conditions. ABB has considered all these demands during development of their dedicated mill functions. By adding an additional controller (mill controller), not only a lot of application related functionality and protection is included, but also the interface between the mill drive system and the customer’s distributed control system (DCS) is simplified."

Jan 1, 2011

Pipe Flow Stability of Concentrated Coal-Water Suspensions in the Presence of an Electric Field

Sep 13, 2010

By Tim O’Neil

The earthmover tire shortage has been a case of bust and boom for the tire industry. Tire producers were unwilling to invest ahead of the mining boom. In their defense, though, the metals sector of the mining industry tends to be cyclic, tire manufacturers are not prescient. Until two years ago, low tire demand depressed prices. The incentive to invest in new, big-tire capacity was almost nonexistent, according to Prashant Prabhu, president of Michelin Earthmover Tire worldwide. “There has been very poor anticipation or a miscaluation of the amplitude of the (tire) demand on the part of just about everybody,” said Prabhu. What a turnaround. The earthmover tire market has grown by 30 percent over the past two years. Now there are not enough earth-mover tires and likely won’t be for the next two years. Goodyear said it was offering customers bias-ply tires when it could not supply enough radial-ply tires. Komatsu said it lost equipment sales because it could not provide the tires that customers requested. Volvo and Caterpillar said they are delivering some vehicles without tires, either promising tires later or leaving the customers – mine operators – to find their own rubber.

Jan 1, 2006

By Joseph L. Fournier

Suncor Oil Sands employs delayed coking technology in converting bitumen into synthetic crude oil. Currently up to 10,000 m3 of delayed coke (coke) is produced per day as a byproduct of the upgrading process, of which up to 9,000 m3 per day is placed in dry storage on Lease 86/17. A review was completed to examine the case history of leachate potential experiments from the dry storage of coke and the environmental relevance of coke leachate studies conducted over the past decade. The review included an evaluation of the potential impacts of environmental conditions within the location of coke storage, including precipitation pH, as well as daily and annual ozone trends. Coke leachate potential has historically been characterized using standard leachate testing protocols (i.e., TLCP, SPLP) together with other studies that have employed strong acids and oxidizing agents in the extraction fluids. The present paper highlights prevailing conditions in the Athabasca Valley air-shed with emphasis given to ambient ozone (oxidizers), as well as precipitation pH and acid input deposition rates, and will demonstrate that TCLP / SPLP tests lack the intended environmental relevance relative to the conditions under which coke is stored.

May 1, 2011

By S. J. Davenport

The increased consumption and importation of fluorspar and cryolite (1)3/ in recent years, and especially the addition of fluorine compounds to drinking water in the United States, have aroused renewed interest in the properties of such compounds and possible health hazards incident to their use. It has been suggested that the issuance of a revision and elaboration of Information Circular 7311, The Hazards of Hydrogen Fluoride Poisoning in the Mineral and Allied Industries, which hay been out of print for some time, would be opportune. Fluorine minerals have been known since the Middle Ages. Fluorine was isolated in 1886 by Moisson (2).

Jan 1, 1954