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By S. McGinn

The Brunswick Mine Diesel Particulate Filter Study was one of several research projects initiated by the Diesel Emissions Evaluation Program (DEEP). The study was carried out at Noranda?s Brunswick Mine in Bathurst, New Brunswick by Noranda Technology Centre and Brunswick Mine personnel with the collaboration of Natural Resources Canada - Canada Centre for Minerals and Energy Technology (CANMET), National Institute of Occupational Safety and Health (NIOSH), Andreas Mayer of VERT, and diesel particulate filter (DPF) system suppliers. The study began in early 2000. Field evaluations continued for 20 months. The final report?authored by Sean McGinn?was submitted to DEEP in the Autumn of 2003.

Jan 1, 2004

By Robert B. Parsons

"The tax reform process marches on. The December 16, 1987 measures tabled by Finance Minister Michael Wilson represent one more step toward the objective of total reform of Canada's income and sales taxes. While the income tax changes are taking shape, much work still needs to be done on the sales tax side of the coin.IntroductionOn December 16, 1987 Finance Minister Michael Wilson tabled measures to implement the changes to Canada's income tax system that were proposed in the June 18, 1987 White Paper on Tax Reform. The measures were set out in a Notice of Ways and Means Motion; draft legislation relating to preferred shares, research and development expenditures; and draft regulations regarding capital cost allowance, certified films, flow-through shares, and the resource sector. The reaction of the government to the recommendations made by the Finance and Economic Affairs Committee Report on Tax Reform (the Blenkarn Committee), the Report of the Standing Senate Committee on Banking, Trade and Commerce and through consultations with interested groups and organizations, business, labour and individual Canadians is set out in a booklet of supplementary information.The basic features of the reformed income tax system set out in the White Paper remain. However, a number of significant changes have been incorporated in the Notice of Ways and Means Motion and other material. The following comments address those area s where changes have been made to the original White Paper proposals."

Jan 1, 1988

By AIME AIME

THE American Engineering Council, which is the working body of The Federated American Engineering Societies, held its first meeting in Washington, Nov. 18 and 19, 1920. The Federated American Engineering Societies was formed in Washington in June and is composed of engineering and technical societies, national, state, local and regional. These Member Societies elect delegates to the American Engineering Council, which is the administrative body of the Federated. The meeting was called to order by Richard L. Humphrey, Chairman of the Joint Conference Com¬mittee, and the program (which is printed below) was carried out without substantial change by E. S. Carman, who was elected temporary chairman. Under the Constitution, the Council appoints an Executive Board, the members of which are chosen according to the proportional membership of the vari¬ous Member Societies in their respective districts. Under this plan, with the present membership, 'the national societies will have 14 members and the local societies 6 members on the Executive Board.

Jan 1, 1920

By James F. Reynolds

Introduction There are 1.4 Gt (1.5 billion st) of recoverable coal under less than 914 m (3,000 ft) of cover in Colorado in pitching seams. Snowmass Coal Co., in cooperation with the US Department of Energy, introduced the longwall mining method in pitching seams to North America. This venture is a coal mining research program directed toward the profitable production of coal under difficult mining conditions as found in pitching seams of the western US. Snowmass Coal classifies pitching seams into the following categories for longwall on the strike in seams 3 m (10 ft) or less thick: • Flat = 0 to 10°: Normal continuous mines and shuttle cars work efficiently. • Slight = 10° to 22°: The maximum pitch that rubber tired equipment will function. • Moderate = 22° to 40°: The angle of repose of mined coal. • Steep = 40° to 60°: The limit of safe use of this roof support. • Vertical = over 60°. The longwall roof support covered here will work in all pitches except vertical. The shearer and conveyor will work in flat through moderate conditions. Longwalling across strike with this equipment in seam pitch over 60° could be accomplished with an inclined face. Development of the first longwall panel began in 1979 and was completed in 1981. The longwall equipment was installed and mining began on Aug. 11, 1981. Mine Planning and Development The original mine plan took advantage of old works abandoned in the 1960s. The gates were developed on a two-entry system with the entries rising 2° to the strike, allowing water to drain from the face. The mining method was by Alpine F6A road header continuous miners with bridge conveyor type coal transport into 5.4-t (6-st) bottom dump coal cars hauled on 1.1-m (42-in.) gauge track by 7.2-t (8-st) battery locomotives. The initial concept was to haul coal from the longwall by battery locomotive. Lack of discipline, however, was shown in the irregular direction of the gate entries, and local rolls in the coal seams severely limited the capacity of battery locomotives. Current mining law prohibits using an intake escapeway for belts or trolley locomotives. A two-entry system is the simplest method of panel development in a pitching seam. A continuous miner cannot be trammed from one entry to another because of steep "X" cuts. Thus, the development requires a continuous miner in each entry. The configuration of the old mine works resulted in a first panel longwall block of three 108 m x 1.6 km (355 ft x 5,400 ft). In panel development, the use of battery locomotives for coal hauling became evermore costly. When the panels were completed and the setup room finished, the lower gate entry was changed to a belt entry and battery locomotives were abandoned. A new slope was driven and the mine supply system was converted to rubber tire diesel supply. The latest generation of roadheader and standard high powered shuttle car-to-belt system is now used for development. Selection of Longwall Equipment Longwall mining across the strike on pitching seams is currently practiced in many nations. Equipment similar to that used by flat seam longwalls is available for pitching seam use in Great Britian and Germany. Face equipment includes a twin outboard armored face conveyor. It was selected to give maximum retention of coal on the conveyor due to flight rigidity and to prevent coal from sliding down the face and jamming the lower belt gate. Also selected was a 22-mm (0.9-in.) Dowty twin-outboard face conveyor for a 106-m (350-ft) face with a single 112-kw (150-hp) drive

Jan 12, 1983

By Keith L. Harris

Surprisingly, real gross national product (GNP) surged at a seasonally adjusted annual rate of 4.3% for the first quarter of 1987 according to preliminary estimates made by the Department of Commerce, the highest rate in 3 yr and significantly above the revised fourth quarter 1986 rate of 1.1% (table 1). The spurt, however, was caused by an unusual $59.5 billion rise in inventories, mostly cars and trucks, and there was little support from other sectors of the economy. Motor vehicle inventories rose as consumers continued to tighten their purse strings--consumer spending declined 0.4% for the second quarter in a row. Nonresidential and residential fixed investment and government purchases of goods and services were also down from the previous quarter. The increasing cost of energy was the major factor in the jump to 3.696 in the rate of inflation, as measured by the fixed-weighted price index for GNP, and rising inflation also helped put a damper on consumer spending. The underlying good news was that the trade deficit shrank for the second quarter in a row as imports declined at an annual rate of 11.1%. Also, profits in the manufacturing sector rose strongly in the fourth quarter, and for the first time in 9 quarters, the primary metal industries became profitable (table 1). If one discounts the anomalous inventory growth, the bottom line is that the economy continues to grow at close to the expected 2.5% level experienced over the past 2 yr. Of concern over the next several quarters, though, is the impact of the large over- hang of motor vehicles inventories on the economy. EMPLOYMENT The civilian unemployment rate declined to 6.636 in March after remaining at 6.7% for the previous 3 months. Employment continued to expand in February and March, although growth was significantly slower in March than in previous months. The manufacturing sector, however, lost 24,000 jobs in March after gaining 46,000 in February. Three-quarters of that gain came when striking workers at USX Corp. and Deere & CO. returned to their jobs. Employment in the manufacturing sectors of direct interest to the mineral industries has generally been increasing for at least the last quarter, while worker hours for these sectors have been on the upswing since April 1986 (figures 1 and 2).

Jan 1, 1987

By Dexter C. Hatch

At MacIntyre Development of the National Lead Company, Taha s, New York,, the flotation plant was set up to recover ilmenite from the finer size fraction of the ore that cannot be efficiently treated in the main gravity-magnetic separa¬tion process. It was later expanded to handle the reground middlings from the tables wetherill magnetic separators. The ilmenite-magnetite ore is ground to minus 20 mesh in five 6 x 12 ft. rod mills in closed circuit with DSM screens. The minus 20 mesh screen undersize is pumped to four parallel sections each consisting of two rougher wet-magnetic separators and one cleaner separator for magnatite removal. The screen undersize from the fifth section is distributed to all four sections. The magnetite removed in the roughers is pumped back to the cleaners and the cleaner magnetite is dewatered in rake classifiers and carried by belt to the winter plant or the stockpile area. The nonmagnetic sands from rougher and cleaner magnetic separator are sized for table feed in eight pocket hydraulic sizers. The slime overflows from the Crocketts, the sizers, and the magnetite rakes are collected and pumped to three-inch cyclones for thickening and desliming. The cyclone underflow is the principal flotation plant feed.

Jan 1, 1962

By S. Heukelman

Zinc or, a zinc refinery in South Africa, uses oxygen enrichment of up to 26% O2 in its fluidizing air to increase concentrate-throughput in its fluidized bed roasters. The aim of the study is to determine whether O2 enrichment can be reduced by introducing micro-pelletized concentrate into the feed blend, while maintaining concentrate throughput rates and calcine quality. A laboratory scale fluidized roaster was used to determine the strength and oxidation kinetics of suitable micro-pellets. The strength of the pellets was determined by the extent of attrition during roasting. It was found that micro-pelletization decreases the fines in the feed to the roasters; the ?500 µm fraction decreased from 87% to 10%. The micro-pelletized particles do break down during roasting, which increases the -500 µm fraction to 31%. The general morphologies of the roasted particles are similar to those found by previous workers. Micro-pelletized concentrate particles require more time than non-pelletized concentrate particles to oxidize in the roasting step, although this is less than the mean residence time of the Zincor roasters. Roasting micro-pellets in O2-enriched fluidizing air increased the reaction rate.

Jan 1, 2011

By Haskiel R. Shell

While the original purpose of the Bureau of Mines work on fluorine micas was to synthesize large single crystals or film suitable to replace natural muscovite or phlogopite, the objective was broadened to include development of the many possible fluorine micas as a class of new, unique materials. Several methods were developed for the synthesis of the fluorine micas at atmospheric pressure: Solid state reaction, melting in crucibles, internal resistance electric melting, and arc resistance electric melting. The latter two methods are now med commercially. A variety of fluoromicas were synthesized by isomorphic substitution including disilicic, trisilicic, and tetrasilicic. Fluorophlogopite, KMg3AlSi3O10F2, is the fluoromica most widely used. While most of the fluoromicas are completely stable to water, many water-swelling fluoromicas and fluoromontmorrilonoids were synthesized. Single crystals or film of the fluorine micas were grown to 2 inches or more by a number of methods, but none has as yet proved economical. In the report, detailed data and descriptions are given on compositions, syntheses, products, and uses, and on the properties including physical, dielectric, chemical, X-ray, optical, and structural.

Jan 1, 1969

By Joseph J. Feiler

Fires in underground coal mines are persistent problems anywhere in the world that coal is mined. Coal fires pose safety and health hazards in the form of mine subsidence, loss of energy reserves, destruction of property and surface improvements, and air pollution. In 1995, the US Bureau of Mines (US-BM), in cooperation with the Colorado Division of Minerals and Geology (CDMG),entered into a contract with Goodson & Associates Inc. (GAI) to design and field test the effectiveness of a new foamed grout technology called ThermoCell. GAI is a Lakewood, CO geotechnical and mining reclamation engineering firm. The company developed ThermoCell to control and extinguish underground coal fires. The viability of the special grout and the technology of application were established during a full-scale field demonstration at the abandoned IHI Coal Mine fire, near Rifle, CO. Following acquisition of additional funding by CDMG in 1999, Goodson returned to the site in April to continue the grouting to fully extinguish the IHI fire.

Jan 1, 2000

By Keith L. Harris

Real2 gross national product (GNP) grew at a seasonally adjusted annual rate of 1.3% in the fourth quarter and at 2.5% for all of 1986, according to the most recent Department of Commerce estimates table 1). The 1986 GNP growth was the lowest since the recession in 1982, and was slightly below the estimate published in the last issue of Minerals and Materials. Barriers to greater economic growth in 1986 included the Federal budget deficit, the trade deficit, reduced energy-sector investment because of low oil prices, and uncertainty over changes in the Federal tax code.3 Major sectors of the economy responsible for the fourth-quarter growth included real Government purchases of goods and services, up $19.9 billion from the third-quarter level; real net exports, up $12.2 billion; real residential investment, up $3.0 billion; and nonresidential fixed investment, up $1.5 billion. The increase in Government purchases of goods and services was attributed to the S25.1 billion rise in net purchases of farm products by the Commodity Credit Corp-oration. Real personal consumption expenditures and inventory investment declined, however. Personal consumption expenditures declined primarily because of reduced motor vehicle purchases. Despite only modest growth during the fourth quarter, the economy improved significantly because of the narrowing of the trade deficit and growing employment (table 2) while maintaining low unemployment and inflation rates. Business sounded an optimistic note, with planned increases in current-dollar capital spending of 0.9% for 1987 compared with a 1.7% decrease in 1986. While it is primarily the nonmanufacturing industries that expect to increase investment from 1986 levels, some manufacturing industries are increasing investment by significant percentages as well, notably the steelmaking and nonferrous metals industries (table 3).

Jan 1, 1987

By Ting Ren, Lihai Tan, Alex Remennikov, Xiaohan Yang, Xueqiu He

"Due to recent coal bursts in Australian coalmines, research of coal bursts has attracted intensive interest from mining researchers and engineers worldwide. Previous research has shown that the sudden drop of fractal dimension may be a precursor of catastrophic failure of rock. This paper examines the fractal characteristics of temporal-spatial distribution of acoustic emission signals released during the compression loading process of coal. This research suggests the possibility of coal burst forecasting based on acoustic emission data. The concept and calculation equation of fractal dimension is introduced in this paper. Additionally, uniaxial compression experiments of Australian coal samples are conducted, and the acoustic emission waveform and 3D location are recorded simultaneously by eight sensors Express-8 AE monitoring equipment in the loading process. The experimental results indicate that the continued slowdown of fractal dimension in time sequence can be used as a precursory signal of coal sample brittle failure. The fractal dimension of the spatial distribution of acoustic emission events decreases with the evolution of coal fracturing.INTRODUCTIONCoal bursts refer to the catastrophic failure of overstressed coal subject to the dynamic and static loads. In recent years, coal bursts have occurred in major coal mining countries and this phenomenon has attracted the research interests of international mining and geotechnical scholars. A total of five coal burst accidents happened in Australian coalmines since 2014. On October 20, 2018, a coal burst occurred at Longyun Coalmine in China’s Shandong province, which led to 21 fatalities. Unfortunately, even after decades of research, it seems neither more accurate forecasting methods nor comprehensive controlling measures put forward by researchers have solved the problems posed by coal bursts.As an instantons energy releasing process, coal bursts are always associated with energy dissipation in the forms of acoustic emission, micro seismicity, and electromagnetic radiation (Yamada, Masuda, and Mizutani, 1989). It is believed by many researchers that the frequency–magnitude relationship of micro seismicity induced by rock failure satisfies Gutenberg-Richer relationship as well (Feng et al., 2017). Hence, based on the principal and theory of earthquake source locating, micro-seismicity monitoring equipment has been adopted in many coalmines to locate seismic event origins associated with coal and rock failure in an attempt to better forecast coal and rock bursts. Although many parameters such as b value (parameter of Gutenberg and Richter’s law) (Lu et al., 2015) have been adopted as indicators of risk, the forecasting of coal bursts is still of low accuracy. The same is true with earthquake prediction, as it remains as a worldwide problem even after decades of research and practice. Acoustic emission (AE) methods are now widely adopted to detect rock failure processes under an applied stress for application predicting the abrupt failure of rock in the laboratory (Li et al., 2017). Previous studies have found that significant overlap exists between research regarding AE and micro seismicity with respect to generation process (both are concerned with the generation and propagation of elastic wave) and event origin location, as geophysical signals of both are same (Lockner, 1993). That is, the frequency–magnitude relationship and early-warning indicators found by AE research in the laboratory have a potential applicability to in-field micro seismic monitoring of coal bursts. Through experimental study, Feng and Seto found that the temporal distribution of acoustic emission counts of rock have distinct fractal structures during load-increase processes (Feng and Seto, 1999). Landis and Lucie found good correlation between fracture energy and AE energy during testing of mortar specimens as well (Landis and Lucie, 2002). Based on preliminary experimental study, many schol"

Jan 1, 2019

By AIME AIME

It is with the deepest personal sorrow, and with the regrets of the Steel Company of Canada, that I report to you the death of one of our most valued associates, the late Frank B. McKune, superintendent of the Open-Hearth Department of our company. Many of you will remember Mr. McKune for his long attendance at these meetings, for the intelligent interest he took ill them, as well as for his innovations in steel-production practices.

Jan 1, 1940

By W. A. Gibson, A. D. Trujillo

The Santa Rita copper deposit first served as a source of native copper for Indian implements and weapons. In 1801 Santa Rita copper, trans- ported by mule train to Chihuahua, began to be used commercially for making coins. It was a small- scale operation made difficult by Indian raids, transportation costs and depletion of the higher grade ores. There was, moreover, no known method for economically extracting copper from the under- lying low grade sulfide ores. Originally, copper and copper oxide ores were mined by underground methods, but there was virtually no development of the deposit-which became United States territory after the Treaty of Guadalupe Hidalgo in 1848-for almost a hundred years. A number of small underground mines had been started during that time, but it was not until 1873 that all the principal claims were consolidated under one control.

Jan 1, 1966

By I Thomson, L D. Black, R G. Boutilier

The social license to operate (SLO) began as a metaphor for the ability of communities to stop mining projects. Soon people began to speak of levels of social license and the ability of communities to raise costs without completely stopping exploration or mining activities. Today the concept has spread to other industries and is evolving towards becoming a general management perspective on the socio-political rights and responsibilities of the corporation. The business case underpinning the SLO perspective on management is the need to assess and manage socio-political risk. For mining companies, socio-political risk has been steadily rising for several reasons, including the efforts of non-government organisations (NGOs) to pre-empt government policy options; the entry of mining companies into jurisdictions weak in the rule of law; and the weakness of global economic and financial regulation. In this perilous world beyond the comfort zone of effective government, mining companies must build their own socio-political stability by engaging directly with stakeholders to develop a strong SLO. In order to become a practical management perspective, the SLO needs to be measurable, which amounts to measuring the socio-political risks and opportunities presented by stakeholders. We present the results of efforts since 2009 to develop a globally reliable and valid measurement tool at the project and industry levels, validated in studies in Australia, Bolivia, Mexico and the USA. A factor analysis suggested four factors that mine management can address to raise their SLO level. The most chronically neglected factor involves the political right of the corporation to foster more equitable social contracts locally and regionally in both developed and developing countries. We conclude with recommended steps to earn and maintain the social license at the project and industry levels.CITATION:Boutilier, R G, Black, L D and Thomson, I, 2012. From metaphor to management tool - How the social license to operate can stabilise the socio-political environment for business, in Proceedings International Mine Management 2012, pp 227-238 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 20, 2012

By J. -C. Sztuke, M. Cao

ABSTRACT The correlations between froth recovery of coal and air recovery were investigated using a hybrid mechanical flotation column. The particle slurry was fed onto the surface of air-water two phase froths to carry out the tests. Froth recovery was taken as the recovery of particles into the froth product, whereas air recovery was determined by the froth height method. The relationships between froth recovery and air recovery were nearly linear, with greater slopes for more hydrophobic particles. Inside the froth phase, the particles were stratified, with hydrophobic particles concentrated in the upper region and hydrophilic particles in the lower region.

Jan 1, 2013

By M. C. Harris

The past twenty to thirty years have seen unprecedented research activity aimed at understanding the performance of flotation froths. In 1990, Finch and Dobby coined the term froth recovery factor, Rr, to represent the efficiency of the froth in delivering particles from the pulp-froth interface to the concentrate. Originally defined for flotation columns, Rr has also been found useful in modeling mechanical flotation cells, and a number of techniques, based on quite different approaches, have been developed for measuring the froth recovery in industrial flotation cells. None of these techniques is universally successful. This paper reviews the concept of the froth recovery factor, and the basis of each of the techniques that have been proposed to measure Rr, and examines the reasons for this parameter being so difficult to pin down. Advances in Mineral Processing Science and Technology Proceedings of the 48th Annual Conference of Metallurgists of CIM Sudbury, Ontario, Canada Edited by

Jan 1, 2009

By R. J. Goodman, P. Lafleur

This paper presents a current interpretation and projections of recent statistics on raw materials availability based on familiarity with the Canadian steel industry and its development. Problems and opportunities are recognized and discussed.

Jan 1, 1976

By Gordon M. Miner

When I was originally invited to speak to this audience on the subject of the future supply of precious metals I was somewhat apprehensive and suggested that the Program Chairman select someone with more credentials. He declined and the results of our conversation gave me cause to reflect and recall the opportunities I have had over the years and how fortunate I have been to be associated with so many successful companies and knowledgeable people affiliated with the precious metals field. I discovered that since 1935, 1 have worked in or visited most of the gold and silver camps in the United States; have been a leaser of a gold mine in Mohave, California; have both lost and made money in the silver futures market; have worked for two of the greatest precious metals companies in the United States - Homestake Mining Company and Hecla Mining Company, have spent a considerable amount of time in precious metal related discussions with men like Don MacLaughlin, Paul Henshaw, Dick Stoehr, Abe Shoemaker, Bill Love, Phil Lindstrom, Simon Strauss, Herbert and Bunker Hunt and many others. It is those exposures and experiences that I draw onto discuss the subject at hand.

Jan 1, 1980

By Stuart St. Clair

EARLY in 1936, when the American Petroleum Institute issued -J "American Petroleum Industry," which was a survey of the current position of the petroleum industry, and its future outlook, and the figures for petroleum requirements .for 1950 and 1960 were widely publicized by the several oil journals, the impression was given that the petroleum- industry must be nearing maturity and would by 1950 have passed the high' point of its obligations to business progress in the United States.`' Let -us look at the figures which might conduce, this thought. Referring to p. 32 of the report, the total indicated crude-oil requirements in 1940 are 1,099,000,000 bbl-; for 1950, the peak, 1,109,800,000 bbl.; for 1960 a decline to 1,071,020,000 bbl. This downward trend, then established, is probably expected to continue. And this in the face of a crude production in 1935 of 993,942,000 bbl., 38,858,000 bbl.

Jan 1, 1936

By C. J. Allen, L. Battiston

"Introduction It has long been recognized by the hot-dip galvanizing industry that the characteristics of the galvanized coating can be influenced significantly by steel and pro cessing variables. Probably the variable of most concern to galvan izers today is steel chemistry. More specifically, the problem is the excessive reactivity of continuously-cast, silicon-bearing steels. In the past, structural steels processed by general galvanizers were in the low-to-medium ca rbon category and contained silicon at either low impurity levels (as with rimmed steels), or less than approximately 0.10% (as with semi-killed steels). The structures of the coatings produced on such steels are characterized by dense, compact layers of delta and zeta iron-zinc alloy phases and a distinct outer layer of eta zinc, which usually imparts a bright shiny appearance to the coating. The presence of silicon in steel, above the so-called semi-killed levels, is known to cause marked stru ctural changes in galvanized coatings. Such coatings are characterized by a relatively thin delta layer, a thick , coarse zeta layer and frequently an absence of the eta layer. The eta phase, comprising zinc which is carried out of the bath during withdrawal of the work, can be consumed by the continuation of the coating reactions until its temperature drops to the solidification point. This results in a dull grey and often mottled surface instead of the usually bright metallic appearance. These galvanized coatings are usually much thicker than coating specifications requ ire and they are usually more brittle and have poor adhesion to the steel. In service, these coatings tend to develop a rust-like discolouration. With the wider use of continuous casting by the steel producers and the associated additions of silicon in this process, the problem is becoming more important and receiving greater attention from the galvanizing industry ."

Jan 1, 1987