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By Hans Treichl

1. INTRODUCTION For Europe the Arlberg road tunnel signifies the elimination of the largest traffic barrier between Bucharest and Paris in the east-west transversal. Apart from that the tunnel will serve the feeder system to the two north-south links Ulm - Milano, and the Brenner motorway, and links the Inntal and the Rheintal motorways closer together.. Thus, the supraregional road system carrying traffic through the Tyrol and Vorarlberg will considerably be emproved by the Arlberg road tunnel. 2. THE PROJECT The 16.1 km contract section of expressway S 16 includes a ramp section of approximately 2.6 km, the access points at St.Anton and at Langen, and the main 13.98 km section of the road tunnel. This section cuts the link between St.Anton and Langen by 3.7 km, and saves 475 m in altitude. The Arlberg road tunnel is planned to have two tubes with two lanes each. In the first stage the southern tube was under construction. Its traffic capacity is 1,800 car units per hour. The tunnel has a cross section of 9o to 103 m2. The sloping gradients are by 1.3o and 1.67 per cent. Fresh air is supplied and used air removed through a ventilation system, fed at the portals and through two vertical ventilation shafts. One of them, at Maienwasen, is 222 m deep, its cross section 66.5 m2. The diameter in clear is 8.32 m. The vertical shaft Albona is 736 m deep, the diameter in clear is 7.37 m. The tunnels is 9,4o m wide, providing for a 7.5o m roadway plus o.95 m sidewalks on each side of it. 4.7o m above the traffic area the conduits for fresh and used air. A transverse ventilation system with reduced exhaust air has

Jan 1, 1979

By B. McHenry, A. E. Wraith, P. J. Mackey

The Wallaroo smelter on the Yorke Peninsula, South Australia commenced smelting operations in 1861 treating ores from the nearby Moonta and Kadina mines. The plant expanded and modernized on several occasions and was a leader in the successful introduction of new technology to improve operations. It operated continuously until 1923 when local mines became exhausted; in the closing stages of the 19th century it was the largest copper smelter in the world outside of those in Swansea, Wales. In 1892 a small electrolytic refinery was established at Wallaroo, the first in Australia, based on principles developed by Elkington at Pembrey, Wales in 1869. The Wallaroo refinery was specifically built to recover gold and silver from copper produced by smelting gold-containing feed materials shipped from Western Australia. This first venture into electrolytic refining was replaced in 1903 by a somewhat larger refinery which, although modest in size for its time, with a capacity of about 1000 tonnes of cathode copper per year, was very productive in precious metals. Anode copper was produced by an updated version of the reverberatory-based Welsh process until 1910 when barrel-type pneumatic converters were introduced based on American practice; subsequently, anodes were cast by tapping the precious-metals rich "bottoms" portion of converter copper as produced at about one-fifth into the copper blow. The present paper describes the Wallaroo refinery, its anode supply and products, supported by initial observations on a sample of a Wallaroo cathode held in the collection of the South Australia Museum, Adelaide SA, Australia. INTRODUCTION Australia ranked 6th in the world for copper mine production in 2018, with an output of 918,000 tonnes of mined copper, after Chile, Peru, Congo, China and the USA; about 40% of Australian mined copper was smelted in the country. Interestingly, the world ranking of Australia in mined copper has, with a few variations, remained about the same for more than 100 years – of interest, it was also the 6th largest country for copper production at 21,089 tonnes in 1899. At that time, all or most of the copper was smelted in the country (Mackey, 2016). Copper was first discovered in Australia in 1842 in South Australia not far from Adelaide; additional copper discoveries in the region soon followed. At first, copper ore was shipped to Swansea, Wales for smelting (Bampton, 2003). However, in addition to the long, 150 day one-way sea passage, it seems Welsh smelters preferred higher grade of ores – these aspects and likely a mood in the new colony to be independent of Swansea (Evans, 2014) evidently encouraged local smelting at the mine sites using small, Welsh-type reverberatory furnaces fired with hardwood as fuel and operated by Welsh and Cornish migrants. The first large copper smelter in Australia commenced in 1848 at Bremer, near Callington some 60 km east of Adelaide. With larger discoveries on Yorke Peninsula, the Wallaroo copper smelter at Wallaroo Bay on the west coast of the peninsula commenced operations in 1861 (Bell & McCarthy, 2008). Thus began one of the most successful, and in its day, one of the most advanced and innovative plants in Australia if not the world. In the late 1860s, it was considered one of the largest copper smelters in the world (Bell & McCarthy, 2008)

Jan 1, 2019

By R. C. Earlougher

Jan 1, 1970

THE Synthetic Liquid Fuels Act (30 U.S.C., 321-325, and amendments) become law April 5, 1644, and a period of intensive research and development in this field was begun by the Bureau of Mines. As part of this program bulletins were published on a pressure hydrogenation,3 the Fischer-Tropsch synthesis,4 and oil shale.5 The Bureau also has published a short bibliography on coal gasification,6 mostly of a theoretical nature. Because coal gasification is prerequisite to Hither the Fischer-Tropsch or coal-hydrogenation processes, publishing this sizable, collection of technical information in this form will be valuable. The material is presented in three parts, as follows: I. United States Patents. II. United Kingdom, Australian, Canadian, and South African Patents. III. Belgium, French, German, Italian, and Swedish Patents. The domestic patents for this bulletin were collected between 1963 and 1955. Some of the Foreign Patents were collected at the same time and a few of them later in 1961. Part I was published in 1960; Part II was published in 1962.

Jan 1, 1964

By R. L. Brown

This report, summarizing the Bureau of Mines research and technologic work on coal and coal products for the period July 1, 1950, to July 1, 1951, is based largely on publications issued during the year. The sixteenth in an annual series, it gives footnote references to publications giving further details of the research and technologic work described, except in a few cases where research data presented herein has not been published previously. During the year, the national fuels situation was generally one of plentiful supply.3/ Mineral-fuel resources appeared adequate for several hundred years at reasonably increasing rates of supply. Coal-production capacity was in excess of demand; petroleum supplies were adequate; and natural gas use was limited only by pipeline capacity. However, it was pointed out that a world war would drastically change this situation of relative plenty, particularly with regard to supplies of petroleum and its products. Conversion to the use of coal on a large scale would be required, and improved methods of mining and of processing and using coal in solid or fluidized form or converted to liquid fuels could materially contribute to our national safety.

Jan 1, 1952

By M. W. Von Bernewitz

The Bureau of Mines receives frequent requests for information on the treatment of mercury ores, but as its own and almost all other publications on mercury are out of print, the Bureau has prepared this circular on the metal for the prospector and operator of small mines and plants. Mercury, commonly though improperly termed ?quicksilver?, is the only common metal that is liquid at ordinary temperatures. Mercury is used in the amalgamation of gold and silver, in power boilers, explosives, friction-less bearings, laboratory apparatus, lamps, medicine, paint, rectifiers, and for ?silvering.? The last mentioned is being superseded by silvering with silver. The use of mercury boilers may increase when they are thoroughly understood, but amalgamation is -being replaced to some extent by the use of corduroy and other collecting mediums, such as jigs and flotation cells.

Jan 1, 1937

By Mario Terceros H., Bengt H. Fellenius

"ABSTRACTFour strain-gage instrumented bored piles were constructed in a sedimentary, dense to very dense, fine to medium sand in Santa Cruz, Bolivia. Two of the test piles were the normally used bored pile constructed with bentonite slurry and two piles were Bauer Full Displacement Pile (FDP). One of each pair was equipped with the Expander Body, an inflatable steel cylinder that on pressure-grouting provides an enlarged pile toe. Head-down static loading test were performed on three of the piles and a bidirectional test was performed on the fourth pile, a standard pile with Expander Body and a bidirectional cell placed immediately above the EB. The latter pile was tested in 3 phases. First by activating the cell, second, by a head-down test, and, third, by a repeat bidirectional cell test. The static loading tests proved the shaft resistance of the FDP pile to be about twice that of the standard bored pile and that the Expander Body more than doubled the toe stiffness. The strain-gage records showed that the standard bored piles had multiple bulges and neckings, which affected the evaluation of the axial stiffness and load distribution of the piles. The testing programme was used for a prediction event with 60 persons, ahead of the tests, submitting predictions of the load-movement curves for the test piles and also a capacity appraised from the curves.1. INTRODUCTIONOn April 23 - 26, 2013, the First International Conference and Seminar on Deep Foundations was held in Santa Cruz, Bolivia under the auspices of INCOTEC SRL, the UAGRM University, and the Bolivian Association of Civil Engineers and Chamber of Construction. To coincide with the conference, a research study on construction and static and dynamic testing of four instrumented bored piles was undertaken. To ""add spice"" to the conference, a prediction event was organized on the test programme. This paper presents the soil conditions at the site, the type and construction of the test piles, the outcome of the prediction event, and the results of the static tests.2. SOIL CONDITIONSGeotechnical studies comprising SPT and CPT tests with routine laboratory analysis were performed on recovered soil samples. Three SPT boreholes were put down at three of the locations of Pile TP1, TP2, and TP3, at 5.0 m distance from each other. The SPT procedure consisted of manual hoisting of the weight by three crew members pulling on ropes over a pulley supported by a tripod and letting the weight fall by gravity. The groundwater table lies at 3.5 m depth.Figure 1 shows diagrams of the SPT N-indices and the distribution of water content in the three boreholes. The SPT-indices show the soil density to be compact. The average water content is about 15 %, plus-minus a few percent."

Jan 1, 2014

By J. B. Mawdsley

Introduction The writer was instructed to visit the Chibougamau region during the field season of 1927 and report on the mineral discoveries that had been made there since 1911. lt was deemed advisable to obtain detailed information regarding the rocks underlying the area in the vicinity of these recent discoveries. Accordingly an area 60 square miles in extent was mapped. The outcrops were studied along the water courses and along bush traverses spaced at half-mile intervals between these water courses. The completion of the rest of the summer's programme allowed only three weeks for this work. lt is from this small, mapped area, and this necessarily cursory survey, that the material for this paper was obtained. Location And Means Of Access The name Chibougamau district is applied loosely to an ill-defined area of about 1,000 square miles lying mostly north and west of Chibougamau lake in the Province of Quebec. The lake is approximately half way between lake St. John and James bay. It lies 150 miles north of the Canadian National railway and 40 miles south of Mistassini?lake.

Jan 1, 1928

By Allan M. Hale

The central Florida phosphate industry is not a recent development. The first phosphate mining occurred in approximately 1888 (1). Many of the original mining companies were "wildcat" operations operated with rapid phosphate extraction as the sole purpose and no long-term commitment to development. Many of the early pioneers were ill-equipped to mine phosphate at either a practical or economical level; as a result many of these early companies "folded" after only a brief period of operation. However, as these early companies went out of business, several large companies developed, expanded their mining territories bought up the folding companies and by 1903 (little more than 10 years after the first mines were started), approximately 37 of the original 60 mines were control- led by three major companies (1). In the early period, mining reclamation was nonexistent. The mined out areas were left to revegetate and reclaim "naturally" over the period of many years. Reclamation practices were only started relatively recently and the various reclamation techniques developed and used in the past have continued to be employed with varying degrees of success through the present time. The reclamation techniques used in the past and currently include land and lakes restoration, sand tailing reclamation, slime ponds reclamation and overburden fill.

Jan 1, 1980

Mine drainage and mine reclamation are topics of major interest to the mining industry, federal and local governments, and the general public. This publication and its companion three volumes are the proceedings of a conference held in Pittsburgh, Pennsylvania, April 24-29, 1994. There were twelve sessions (69 papers) that dealt with mine drainage, including modeling, geochemistry, prediction, treatment, control strategies, characterization, hydrology, and case studies. These sessions comprise volumes 1 and 2. The six sessions (34 papers) that dealt with reclamation and revegetation of disturbed lands are included in volume 3. Volume 4 includes the six sessions (34 papers) that dealt with such topical issues as fires at abandoned mine sites, subsidence, hydrology, mine wastes, and policy. Poster session presentations are represented by 49 papers and 92 abstracts that have been placed in the back of volumes 2, 3, and 4, consistent with the subject of that volume.

Jan 1, 1994

By James M. Barker

Industrial minerals are critical to most aspects of modern society. They are pervasive in both industry and in everyone's lives (McVey, 1989; Barsotti, 1993). They are also the dominant class of minerals produced in the United States but this fact is little known outside the industry. For example, in 1993 (U.S. Bureau of Mines, 1995, table 1) industrial mineral dollar value was double that of metals ($20.86 billion vs. $10.88 billion) and employment levels were nearly so (74,000 vs. 40,000). A further difference is that transportation tends to dominate production costs (FOB end user) whereas they are much less significant in other mining ventures or other industries. Finally, metal mines are more concentrated west of the Mississippi; industrial mineral operations are more prevalent to the east (U.S. Bureau of Mines, 1995, p. 16-17). The significance of transport cost is discussed in Part 2, which is essentially Barker and Austin, 1995. Part 1 will update and expand portions of Barker and Austin (1995) and provide a more detailed discussion of import/export relationships using a China/United States reference point because of China's dramatic influence on some industrial mineral markets since the mid-1980s (barite, etc.).

Jan 1, 1996

By Pilon CG, Deakin RC

It is proposed that a waste rock dump be constructed on slopes consisting of soft colluvium and weathered Chim Formation mudstone at the Porgera Gold Mine, in Enga Province, Papua New Guinea (PNG). Geolog- ical, geomorphological and geophysical investigations were conducted in support of geotechnical studies to assess the physical character of the 6km2 site. Geomorphological studies focused on the extent and nature of colluvium cover and landslide activity. Detailed ground traverse mapping resulted in classification and delineation of eight terrains and seven material types. Seismic refraction and resistivity profiling, combined with drilling, provided subsurface data. Results were presented as standard profiles, coloured contoured sections and plans. Subsurface features, including deep colluvial channels, buried cliffs, slump blocks and buried alluvial channels, were identified. Results of the combined investigations allowed designers to model the colluvium/ bedrock surface and identify critical areas of deep, mobile colluvium and weak bedrock. A design approach was developed which accounted for the morphology of landslide systems and distribution of colluvium types.

Jan 1, 1991

By J. Thompson

Paper written on project work carried out in partial fulfilment of B. Eng (Mining Engineering) degree A study into the stability of strike gullies at TauTona mine was to be carried out. In reaching the conclusions to follow, a three-stage process was followed. ?A literature study as well as discussions with management and workers alike to gain their inputs and perceptions. ?An ESH Department survey into the history of transgression from proper mine standard in TauTona strike gullies. Unfortunately records were found to be scarce and obscure and the importance of better inter-departmental recordings cannot be stressed enough. ?An underground survey of 11 pre-selected gullies distributed in both the UCL and LCL reef horizons. This stage is to carry the greatest weight in the points to be brought forward in this report. The process highlighted and ranked the following areas as the most critical role players in the deterioration of strike gullies: ?Poor blasting practice ?Sub-standard siding depth and lead-lags ?Split sets ?Off line gully development ?Adverse geological features. The following has been suggested to the mine to help reduce strike gully instability. ?Where possible, maintain lead-lags below 7 m?else increase the siding depth to suit. ?Decrease the gully width standard to 1.2 m (especially in ?high risk areas?). ?Discourage drillers from drilling side holes in gully face blast pattern. This will allow for time in which tendon support can be kept up to date. ?Ensure split sets are installed 1 m behind the gully face so as to prevent opening up of fractures. ?Utilize the centre split set in the 1:2:1 pattern to maintain the proper gully line. ?When adverse conditions prevail, it is necessary to apply a special support plan not only to the panel face, but also (just as importantly) to the gully as well. Shotcreting of the gully hanging is a suitable long-term consideration for providing the additional a real coverage needed. List of Abbreviations [CL Carbon Leader M/O Mine Overseer UCL Upper Carbon Leader FOG Fall of Ground LCL Lower Carbon Leader H/W Hanging Wall ERR Energy Release Rate F/W Foot Wall WDL Western Deep Levels ESH Environmental Safety and Health ]

Jan 1, 2002

By V. K. Gupta

"Effect of mill speed on grinding kinetics has been investigated with a view to using mill speed as a manipulated variable for control and optimization of the grinding circuit performance under variable ore hardness conditions. Dry and wet batch grinding tests were carried out for quartz, limestone and cement clinker in a 29 cm x 18 cm laboratory ball mill. Mill speed values selected were 55 and 70% critical. In the case of dry grinding operation, with an exception of quartz, for all materials studied the effect of mill speed on grinding rate was found to be insignificant for sizes finer than about 35 mesh. In the case of wet operation, grinding rates were found to be approximately proportional to the mill speed. The implications of these results are discussed.INTRODUCTIONIt is well known that mill speed has a considerable effect on the grinding rate of the ore particles l-3 For particles of a given size there is an optimum speed at which mill grinding efficiency is maximum (i.e. specific energy consumption is minimum) 3•4. Mill speed can, therefore, be effectively used as a manipulated variable to deal with the disturbances arising from changes in the size and hardness (grinding rate) of the ore being fed to the grinding circuit. Though, it has not been the case so far, with recent developments of ring motors2 and frequency inverters5 a continuous variation of mill speed has now become feasible, and it is expected that mill speed control will soon be a regular feature of plant operation2,6."

Jan 1, 1985

By W. R. K. Wu

This bulletin traces the development of high-pressure, coal and tar hydrogenation technology, based on an intensive review of the pertinent literature. The bulletin was written as a part of the Bureau of Mines research program on synthetic liquid fuels. It covers the history and economics of the process; the chemical aspect of hydrogenation of coal, tar, and middle oil; the engineering aspect of converting coal and tar to liquid fuels, principally gasoline; and the equipment for the process. The literature covered includes documents of the United States and British Governments, journals, and other publications. Bureau results in the hydrogenation field are also incorporated.

Jan 1, 1968

By Fritz Wald, Martin Weinstein, Herbert E. Bates

ONE of the methods for preparing a fiber-reinforced composite is that of directional solidification of a eutectic melt. Its major drawback lies in the fact that the matrix in this case is a pure constituent (or a terminal solid solution of fixed concentration) and the ratio of fiber to matrix volume is fixed. Only very few, if any, pure metal matrices possess technically useful properties, and the necessity for alloying is the inevitable consequence of this fact. Nevertheless, structures similar to binary eutectic ones can be obtained in higher-order systems by pseudoeutectic reactions of a type where crystallites and a solid-solution matrix are simultaneously precipitated from a liquid.1"3 Trials to solidify such alloys directionally—the matrix consisting of a solid solution of chromium, nickel, and silicon and the reinforcing phase being Cr3C2— will be reported elsewhere.4 This note describes constitutional studies carried out primarily to determine -the position of the pseudoeutectic and further to insure that no undesirable reactions between the reinforcing phase and components of the matrix occur in the solid state at elevated temperatures. In the investigation it was specifically desired to reinforce a matrix which is as close as possible to the 80/20 Nichrome composition with Cr3C2 to insure good oxidation resistance and improve the strength at high temperatures. No konstitutional information on the quaternary C-Cr-Ni-Si svstem in the range of interest was found in the literature. Nevertheless, the two most important ternaries c-cr-Ni5 and have been completely investigated. On C-Cr-Si some investigations have been conducted,7"9 and C-Ni-Si was studied with a few alloys in the course of the present investination 9 Eight alloys were prepared to investigate the changes in the constitution of the ternary C-Cr3Ce-yNi eutectic5 with silicon contents up to 10 wt pct. Five alloys were made with varying chromium and carbon contents around compositions containing -60 to 70 wt pct Ni and 5 to 6 wt pct Si. The latter alloys were designed to locate the y(Ni-Cr-Si-C)-Cr3C2 pseudoeutectic reaction and to determine the maximum chromium content in solid solution compatible with a two-phase equilibrium between y and Cr3C2 only. The alloys were prepared from electrolyte nickel, semiconductor-grade silicon, high-purity chromium (99.999 pct pellets), and semiconductor-grade graphite. They were melted inductively in high-purity alumina crucibles under flowing argon. Twenty-gram charges were prepared and investigated by optical microscopy (including hot-stage investigations), X-ray powder methods, and electronmicroprobe analysis. The alloys were studied in the as-cast condition and also after a homogenization annealing treatment of 48 days at 900°C in evacuated quartz ampoules. The structures of all alloys based on the ternary eutectic plus silicon in the as-cast state consisted generally of an inhomogeneous solid solution and at least two other phases. Annealing of the alloys showed that the solid solution was homogenized but that an incomplete solid-state reaction had taken place in all alloys with silicon contents over 5 wt pct. This reaction is clearly visible in Fig. 1 around the large Cr3C2 crystals (gray areas). Below this concentration, the alloys consisted of a homogeneous matrix and precipitates of Cr3C2 plus graphite, Fig. 2. The Cr3C2 was entirely unreacted here. From these observations and subsequent X-ray and microprobe investigations, it was deduced that the

Jan 1, 1969

By Harold J. Rose

The economic situation in Switzerland during recent years has resulted in theoretical studies , engineering development work , and many commercial installations of ingenious methods for using energy more efficiently . The purpose of the present investigation was to learn of recent Swiss developments for the more effective use of coal , which comprises 98.9 percent of the romaining known mineral - fuel reserves of the United States .

Jun 1, 1947

By Jon Pocock, Ashma Singh

The traditional approach for the beneficiation of South African siliceous sedimentary phosphate ores has been reverse cationic flotation. The robustness of this approach, however, has been a concern due to its sensitivity to parameters such as slimes content, headgrade ( P2O5 and SiO2 content), reagent dosages and conditioning times. The phosphate mineralisation for the ore body under investigation is predominantly carbonate fluorapatite composed of mainly quartz and apatite and minor amounts of chlorite, ilmenite and carbonates. Beneficiation of low grade sedimentary ores containing calcareous impurities, such as calcite and/or dolomite in addition to siliceous gangue, is required to meet the increasing demand; therefore, much research has been carried out to find an alternative technique to beneficiate this material. This paper investigates traditional flotation approaches versus the currently adopted ‘Crago Process’. Comparative results are presented in terms of upgrade potential for the production of concentrate rock for downstream applications. The novelty of the ‘Crago Process’ lies in its double stage approach, i.e. direct fatty acid flotation followed by reverse cationic amine flotation. The Crago process was able to achieve higher upgrades reporting at 32.1% P2O5 compared to conventional cationic flotation only achieving grades of 18.5% P2O5. Furthermore, the recovery gain was 3%.

May 13, 2023

By Clyde Sitterud

Presentation Agenda ?Global Mining Tire Demand ?What is driving it? ?Latest Situation ?How long it will last? ?Michelin?s Response to Increase Supply ?New plant ?Additional presses ?Recommendations for Mining Users ?Treat tires as your major assets ?Areas of attention that will produce immediate results

Jan 1, 2005

By PHILIP N. MOORE

THE development of the power of the Tennessee River at Muscle Shoals has become a matter of political interest as well as engineering possibility. The controversy over it has been so active that the facts have been obscured, the possibilities exaggerated. Although the members of the American Institute of Mining & Metallurgical Engineers are not generally specialists in hydroelectric development, those who visited Muscle Shoals in October, following the Birmingham meeting of the Institute, were interested, and many of them surprised to learn the actual conditions. These have long been familiar to those who have studied the matter through the reports of the U. S. Engineers on the subject. The approved plan contemplates three dams-No. 1, a low dam close to the City of Florence, planned in the interests of navigation, since the construction of the other dams has rendered impossible the use of the river without it. No. 2-named the Wilson Dam is now under construction. Concerning it political argumentation has waged. No. 3 Dam-much smaller, is planned to be erected several miles above No. 2.

Jan 1, 1925