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EUROPE continued to be unsettled, financially, commercially and socially. October opened with Germany in a state of turmoil following the Government's cessation of passive resistance to the French and Belgians. In many places there were riots with much bloodshed. In Bavaria a military dictator-ship was set up in order to keep peace. In the meanwhile France continued in an uncom-promising position.. Great Britain, having been diplo-matically discredited, disappeared from any prominence in the international picture. Under the constraint of circumstances the policy of deflation in Great. Britain was temporarily abandoned. Perhaps no other course was open, for with declining trade and heavily reduced revenue, and no chance for cutting expenses propor-tionately, a check to deflation comes of its own accord. The effects of this should become manifest in the course of a few months and should appear in the form of an improved margin between the prices for commodities and the wage costs in producing them. About Oct. 20 an effort was made to set up the Rheinland as a separate republic. On Oct. 26 were published communications from Lord Curzon to Secre-tary Hughes and the latter's reply. In these Lord Curzon drew attention to the gravity of the situation in Europe and expressed the hope that France might listen to renewed suggestions for a general inquiry. Secretary Hughes promised American cooperation, in this, with the reservation that the question of inter-national debts should not enter into the situation. In the latter part of October there were military mutinies and disorders in Greece, which resulted in the reestablishment of martial law by order of Col. Plas-tiras, who is virtually the dictator of Greece. The incipient revolt was promptly crushed.

Jan 10, 1923

By W. L. Remick

THE hydrotator coal-cleaning process was developed as an economic necessity to meet the ever-increasing demand for an inexpensive method of cleaning coal down to the sizes ordinarily referred to as "dust." As the most urgent demand seemed to be in the anthracite field, all experimental work has been conducted in that territory during the past 2 years, with the exception of a few months during the strike of 1925-26, when some experiments were performed in the Alabama bituminous fields. The first commercial plant was constructed at the Middle Creek Colliery of the Philadelphia & Reading Coal & Iron Co., Pottsville, Pa. This plant is now operating. APPLICATION The field of application of the process is: 1. Cleaning anthracite fines, ordinarily described as "slush" or "silt." Slush contains all sizes from %2 in. down to and including "dust." (Anthracite passing a 32-in. mesh is also referred to as No. 2 Barley and No. 4 Buckwheat.) 2. Cleaning sizes too fine for recovery by other methods. 3. Removal of coal from sand circulated in the Chance sand-flotation process. 4. Cleaning of bituminous sizes. from 3/8 in. down to "dust. 5. As equipment for the performance of the froth flotation process. 6. Other separating, extraction and _washing. processes which may be considered outside the realm of coal cleaning. PRINCIPLE OF OPERATION Fig. 1 shows the method of classification practised under the Hydrotator patent:1 In coal cleaning the machines are operated as "hindered settling" classifiers, the flow of solids and liquids being so controlled that the units may be combined in series.

Jan 1, 1927

The eastern third of Australia contains an unrivalled Phanerozoic rock record generated by the regional interaction of Gondwanaland with the Pacific and by the global effect of the 400 m.y. Pangaea - Panthalassa cycle. Between the latest Proterozoic (600 Ma) breakup of Proto-Pangaea and the mid-Carboniferous coalescence of the dispersed continents in Pangaea, the Lachlan and Thomson Foldbelts accreted to the craton by Mariana-type (backarc basin) and Chilean-type (continental margin) subduction from eastward jumps of the Palaeo- Pacific rim. Further jumps of the rim of the Permian and Mesozoic Pacific, now expanded to Panthalassa, accreted the New England Foldbelt to the craton. An Early Permian rift basin was succeeded by a Late Permian to mid-Triassic foreland basin which extended between the craton and the foldbelt behind the 10000 km Panthalassan rim, from the Bowen Basin of Queensland to South America, and was host to the productive coal measures of eastern Australia, as the succeeding Jurassic and Early Cretaceous foreland and epicratonic basins included the coal measures, hydrocarbon reservoirs, and aquifers of the Great Artesian Basin. The magmatic arc on the Australian margin ended after the mid-Cretaceous uplift along the Queensland coast that initiated southwestward drainage from the high Pacific rim. The Chilean-type subduction that had prevailed since the Devonian was superseded shortly afterwards by Mariana-type subduction with the successive generation of the back-arc basins of the Tasman Sea, Coral Sea, and other southwest Pacific basins by the migration of the island arc to its present position 2500 km eastward of Australia.

Jan 1, 1990

By Hill G

The Boddington Gold Mine (BGM) is managed by Worsley Alumina Pty Ltd (Worsley) and is located 110 km south-east of Perth, Western Australia. The gold mine, which has operated since mid-1987, was originally constructed to treat 3 Mtpa of gold bearing oxide ores, has subsequently been expanded to treat 7 Mtpa and is presently one of the largest gold producing operations in Australia.During 1990 a Supergene/Basement Plant was constructed to treat 250 000 tpa of copper supergene and hypogene ores and basement ores which contain significant gold grades and which are encountered at the lower levels of the existing oxide orebody. The SupergeneBasement Plant has the versatility to treat a wide range of ore types, producing both gold bullion and copper-gold concentrates. It is a stand-alone facility adjacent to the existing 7 Mtpa gold plant.

Jan 1, 1992

By Larry Rayburn

Augercast piles evolved in the late forties from the process of pressure grouting open holes backfilled with stone. In 1956, a patent was issued for a cast in situ pile by pumping high pressure grout through hollow-stem, continuous flight auger as the auger is gradually withdrawn from the ground. The patent rights expired in 1973 and the use of auger-cast piles greatly expanded with most large deep foundation contractors now installing augercast piles. At one time augercast piles had a bad reputation, partly because of not having a blow count to give some engineers a confidence factor and there were some quality issues. Over the years the quality issues have been eliminated and I am sure the augercast is the most installed pile in private industry and is now being used by some State Agencies.

Jan 1, 2005

By Parrington PJ, Bailey A

Serious exploration for carbonate-hosted lead/zinc deposits in the Pillara district commenced in 1971 when Trend Exploration acquired exploration tenements covering stream sediment anomalies in the Limestone Billy Hills area. Shell Minerals managed the project from 1974 to 1976, and BHP Minerals Limited assumed management during 1976. Carbonate-hosted 'Mississippi-Valley- type' Pb-Zn deposits most commonly occur in Palaeozoic shallow marine carbonate complexes. At Pillara upper Devonian (Givetian/Frasnian) reef complexes are preserved on the flanks of Precambrian basement 'highs'. Within platform and atoll facies limestones sphalerite-galena- marcasite-calcite mineralisation occurs as disseminations, veins and breccia matrix, mostly associated with fractures and fault zones. Early exploration concentrated on detailed surface geochemistry and IP geophysical surveys, with geological mapping and shallow target percussion and diamond drilling. Results were discouraging and did not indicate potential for a shallow base metal resource. During 1976-77 BHP adopted a grid diamond drilling exploration technique and commenced testing an area of approximately 50 sq. km, initially using an 800 m square grid. In 1978 high grade mineralisation was intersected in an area subsequently named Blendevale. This was in the seventh diamond drill hole in the 800 m grid drilling programme, and to date more than 400 holes have been cored in the Pillara area. Detailed drilling at Blendevale has defined a number of mineralised breccia zones within an area of 2.4 km x 0.5 km, at depths of 100 m to 600 m below surface. The breccia bodies are associated with a series of north-south trending normal fault zones, forming a graben structure. The mineralisation occurs as breccia matrix surrounding unaltered limestone clasts, as veins filling steep fracture zones, and as

Jan 1, 1986

By G. M. Ault, G. C. Deutsch

The paper reviews the efforts made to utilize powder metallurgy to solve problems encountered when using alloys at high temperatures. The following subjects are discussed: comparison of wrought and sintered super alloys, sintered aluminum powder, porous materials for transpiration cooling, molybdenum, and cermets. TODAY, powder-metallurgy techniques are be-JL coming increasingly important, producing materials which at the present time cannot be made by any other method. Among these materials are high melting-point metals such as tantalum and tungsten, porous metals for filters and lubricant-containing bearings, electrical contacts and electrodes (i.e., tungsten-copper), cutting tools of the cemented carbides, and magnet alloys. In addition, the powder-metallurgy industry has grown because, through the application of its methods, shaped parts, such as gears, can be produced at tremendous rates with a low scrap loss in comparison with manufacture by casting or forging and machining. In the past few years, by utilizing powder metallurgy, several approaches to the problem of high temperature materials have been investigated. In this paper the authors will review some of the studies on application of materials having properties above 1350°F. Since their experience lies in the aeronautical field, possible uses of powder-metallurgy techniques in the production of aircraft en- gines will be emphasized. A large portion of the work is classified, but such a restriction has not eliminated any field from discussion, although limiting the amount of detail it is possible to present. The development of high temperature alloys from powders and porous metals for cooling will be discussed as well as research done on molybdenum and molybdenum alloys, cermets, and intermetallics. Some studies on the utilization of cermets will be considered along with special problems that have been revealed through these investigations. Special interest in certain factors of sintered aluminum powder (SAP) makes it desirable to discuss this material although its use temperature is below the 1350°F limitation set for this paper. High Temperature Alloys from Powders In general, components made from powders for room-temperature application have been investigated with the primary purpose of taking advantage of the high production rates and economies made possible by powder metallurgy. From the standpoint of properties, the ojective of the powder metallurgist has been to obtain a product comparable to the cast or wrought product that is to be replaced. Comparisons of the properties of alloys made by powder-metallurgy methods with those of similar compositions made by casting and forging are reported in the literature.12 In many cases equivalent

Jan 1, 1955

I The South Platform of the Gippsland Basin is an extensive area of shallow basement covered by a relatively-thin Late Mesozoic-Cainozoic section. Although the sporadic exploration to-date has not resulted in any hydrocarbon discoveries, the area is under-explored and its taste potential has not yet been fully evaluated. The best potential appears to be in areas underlain by the Golden Beach Megasequence where structures are mainly related to basement fault blocks.

Jan 1, 1992

By S. Maurigiannakis

In an effort to promote sustainability in the construction industry, the natural decorative stones that cover large external areas of buildings may be replaced with artificial stones. In this paper the physical and mechanical properties of artificial decorative stones are presented and are critically compared with corresponding natural stones. To test suitability for various applications, artificial stone specimens were subjected to weathering testing (freezing-thaw cycles in a climatic chamber). Mechanical characterization of these specimens was based on uniaxial compressive testing as well as non-destructive ultrasonic testing. Preliminary results show that artificial stones can replace natural stones, thus creating a sustainable development option for the construction industry.

Jan 1, 2003

By Scoble M, Peck J

This paper reviews the instrumentation and monitoring of blasthole drills and electric mining shovels at a surface coal mine in western Canada. The drill monitoring component involved the development and implementation of microprocessor-based hardware on Bucyrus-Erie 45R and 60R drills. Over a two year period 3800 metres of blasthole drilling were monitored The drill data was subsequently correlated with core and geophysical logs towards identifying unique and reproducible ranges of performance parameter data for the different rock types penetrated. Using this technique, the geology of the study area benches was characterized in detail. Once these same benches had been blasted, the performance of a P&H 2800XP shovel was monitored as it worked through the blasted ground. In this regard, the influence of different digging conditions on shovel performance were identified in a range of blast and geological environments within the study area. The precise nature of these environments was confirmed by a correlation with the interpreted drill monitored data and muckpile size distributions obtained from a digital photo-analysis study. The excavation of 500 000 bcm of waste was thus monitored and a digging index derived which reflected variations in muckpile diggability. The paper concludes by proposing an integrated monitoring approach which, as a first step, uses interpreted drill data for explosive loading. This capability would permit greater accuracy in explosives loading ie. charge placement within higher strength lithologies, while avoiding weaker units. The performance of an instrumented shovel would then be monitored as it works through the resulting muckpile. Interpretation of the shovel performance data would determine the overall quality of the blast in terms of a digging index (DI), providing an indication of the relative digging effort and the effectiveness of the blast design.

Jan 1, 1990

By A. J. Leighton

An improved mathematical model with the attendant computer program to calculate multiphase fluid flow in petroleum reservoirs is presented. The model is used to simulate the behavior when a fluid is used to displace hydro-carbon fluids in a reservoir. The method is an expansion of a previously published method, in Bureau of Mines RI 7011, but handles constant injection rate as an alternative to constant pressure. Program documentation is provided along with thorough explanations of the added program features. Using the program, the petroleum engineer can calculate oil recoveries for different flood patterns and operating conditions and select the conditions most likely to optimize recovery. Experience with the previous model demonstrated the need for the improvements in order to simulate reservoir behavior more accurately. The improved method will result in improved oil recovery. In this paper, the significant improvements are described in detail so that anyone interested can put the program to use.

Jan 1, 1975

Senior staff representatives of the Bureau of Mines and the National Institute for Occupational Safety and Health (NIOSH) met in Washington on September 6, 1972, to review and evaluate their cooperative accomplishments to date and to consider the planning and conduct of future coordinated activities. The six presentations given at this joint staff seminar are published here for the benefit of those concerned with the problems of coal mine health, and especially those with responsibilities in administering the Coal Mine Health and Safety Act of 1969.

Jan 1, 1972

By Ann G. Kim

The U.S. Bureau of Mines applied its mine fire diagnostic method to an abandoned anthracite mine fire site in Carbondale, Lackawanna County, P A. The technique to locate fires in abandoned coal mines and coal refuse piles includes the determination of hydrocarbon concentrations in mine gases, the imposition of an underground gas flow direction, and use of a surface mapping method, to define heated and cold zones in underground coal strata. The heated zones at Carbondale were characterized by elevated methane concentrations. The results of 25 communication tests were analyzed to define 2 large (approximately 100 by 250 ft) and 5 small, isolated heated zones. An approximate correlation existed between the location of the heated zones and areas of anomalous snow melt. The correlation between the results of the diagnostic? test and subsurface temperatures was not significant.

Jan 1, 2010

By J. R. Andrews, R. P. Young, J. M. Reyes-Montes

"Microseismic monitoring provides insight into the location and extent of rock-mass fracturing induced by cave mining, enabling interpretation of the cave profile and validation of predictive numerical models. Source location uncertainties can lead to misinterpretation of the inferred characteristics of the fracture network. One principal source of uncertainty is the velocity model used to invert the location algorithm. Large-scale 3D numerical models of modulus changes across a caved mass can represent such complexities in the location algorithms, allowing more accurate interpretation of the microseismic activity. A Northparkes mine case study applies this advanced approach to microseismic data interpretation.RÉSUMÉ Le suivi microsismique fournit des renseignements sur la localisation et l’étendue des fractures de la masse rocheuse induites par l’exploitation par blocs foudroyés; cela permet d’interpréter le profil de la chambre foudroyée et de valider les modèles prédictifs numériques. Les incertitudes quant à la localisation de la source peuvent conduire à des mésinterprétations des caractéristiques inférés du réseau de fractures. Une des principales sources d’incertitudes est le modèle de vitesse utilisé pour inverser l’algorithme de localisation. Des modèles numériques tridimensionnels à grande échelle des changements du module d’élasticité à travers une masse foudroyée peuvent représenter de telles complexités dans les algorithmes de localisation, permettant ainsi une interprétation plus juste de l’activité microsismique. Une étude de cas à la mine Northparkes applique cette approche avancée à l’interprétation des données de microsismicité."

Jan 1, 2016

By Martin Langenderfer, Catherine Johnson, Phillip Mulligan, Kelly Williams

The physical geometry of a charge has a direct correlation to the geometry of the shock wave. This relationship appears strongest within the boundaries of the visible fireball. As the shock wave propagates outward past the limits of the fireball, the theory states that the geometry of the shock wave should even out and become more spherical. This paper investigates pressure vs. time at two distances, one ‘Near Field’ at the extent of the fireball and one ‘Far Field.' The two Fields were instrumented with three free-Field pressure probes from PCB oriented at 0, 45, and 90 degrees to the front face of the charge, in the same horizontal plane as the charge. This orientation allows for the comparison of the shock wave from the face and vertices of the charge. All the pressure sensors were connected to a Data Acquisition System (DAS) recording at 2 million samples per second (2MS/s). Two high-speed cameras, a Phantom and an MREL Ranger II, recorded the detonations for qualitative examination of the fireball, and the shock wave. Three charge geometries were used and compared to the shock propagation of a sphere. The other geometries tested are cylinders, cubes, and tetrahedrons. Charges were made from a PETN based sheet explosive. In the Near Field, a lower pressure is observed along charge vertices with highest pressures from each face. In the Far Field, vertices record a higher pressure, possibly due to the shock waves from the adjacent faces intersecting, indicating that shock pressures do not always even out in the Far Field. This paper will describe the methodology and findings of this experiment and attempt to determine causality for trends in the data gathered.

Jan 1, 2018

By E. V. Koporulina, I. Zh. Bunin, M. V. Ryazantseva

"We studied the mechanism of structural and chemical transformations of columbite, tantalite, zircon and feldspar surface during the treatment by high – power electromagnetic pulses (HPEMP) using the methods of X - ray photoelectron spectroscopy (XPS), analytical electron microscopy (SEM - EDX), Kelvin probe force microscopy and flotation experiments. According to XPS and SEM - EDX data, major changes in the atoms chemical state of investigated minerals surface are related with formation and modification of functional cover and changing in concentration (% at.) of hydroxyl groups on the mineral surface, leading to increase in the contrast of technological properties of the rare metals minerals. Research has identified the optimal parameters of HPEMP - treatment of rare - earth minerals Npuls ? 104, Ttreatment ? 100 sec. improving the selectivity of the flotation separation of columbite and zircon. The difference in mineral recovery into the froth (? e) before and after HPEMP - treatment was about 11 % and 24.5 %, respectively. No significant increase was observed in the flotation activity of feldspar. This study's findings demonstrate the effectiveness of HPEMP - treatment in inducing a controlled change in the structural and chemical properties of rare - earth minerals and improving the process efficiency for the processing of rougher tantalum - niobium gravity concentrates.INTRODUCTIONThe importance of improving the processing methods of tantalum-niobium ores and concentrates is explained by the mineralogical properties of rare - earth ores. These are properties such as the variable mineral, chemical, and grain size composition, complex morphometric properties, and the dissemination of ore mineral grains of micro - and nanometric size. Iron oxide and hydroxide films on the mineral surfaces neutralize the surface physicochemical and absorption properties of the minerals. Both in Russia and globally, nonconventional (non - mechanical) methods are being developed based on physicochemical, electrochemical, and pulsed energy impacts to improve the efficiency of disintegration and liberation processes of disseminated mineral complexes and to enhance the contrast of the structural, chemical, and technological (floatability) properties of refractory ores. This study is devoted to the investigation of the applicability of high – power electromagnetic pulses (HPEMP – treatment) for the change in the structural and chemical properties of rare - earth minerals and improving of the flotation properties contrast."

Jan 1, 2018

By José Fernandes De Oliveira Ugarte

El presente texto describe los resultados de la caracterización mineralógica de muestras minerales de cobre que fueron empleados en el proceso de flotación. Para este proceso, fue necesario conocer la mineralogía de diferentes minerales de cobre de yacimientos tipo pórfido, así como sus asociaciones con los estudios mineralógicos y estudios geoestadísticos por microscopia electrónica de barrido con el sistema de energía dispersiva.

Feb 1, 2014

In recent years, coal beneficiation has gotten considerable attention. Selective oil agglomeration has been accepted as the best method to produce clean coal with a high removal of pyrite sulphur. In this study, spherical oil agglomeration of Datong coal fines was carried out using diesel oil as a bridging liquid. The oil agglomeration has a surface properties based on coal cleaning technique. The effects of fundamental parameters have been investigated including the concentration of bridging liquid, the size of coal particle, the solid content of slurry, the agitation time and rate, pH, surfactants on the agglomeration performance and various salts on the ash rejection and removal of pyrite of the agglomerated products. The optimum conditions of particle size, diesel concentration, solid content, agitation speed and time, pH and the dosage of active agent have been determined as less than 8µm, 20wt%, 1200r/min and 10 minutes, 7.5g/t and 100g/t, respectively. Under these conditions the ash content in the products can be achieved 1.5% below, the ash rejection was up to 92%. It has been observed that ionic strength of the aqueous medium affects the agglomeration performance. The precombustion coal cleaning process based on improved selective agglomeration results in high ash and pyrite sulphur removals. Over 80% removal of pyrite sulphur can be achieved from run-of-mine coals by offering a more cost-effective sulphur reduction solution rather than any other SO2 removal technology. In addition, the removal of pyrite sulphur is very necessary for not only the prevention of environmental pollution but also economical reasons.

Jan 1, 2014

By Haldane J. S.

(Paper presented at the Institution of Mining Engineers' general meeting held in London on 8th June 1916.) It was shown in the last Supplement to the Registrar-General's Reports, in connection with the census of 1901, that the general death-rate among colliers was considerably lower than in the great majority of occupations but that there is an exception to this in the case of colliers above the age of 55. Examination of the statistics finds that the excessive death-rate among old colliers is to a large extent only apparent, and that the real excess of bronchitis from which they have suffered has greatly diminished. It is concluded: (1) that good ventilation is of considerable importance to the health and continued working efficiency of miners, as well as to their safety from accidents; and (2) that there is no real statistical evidence of harm resulting from the inhalation of coal-dust or shale-dust in the quantities ordinarily breathed by miners, and a strong presumption that the dust they breathe protects them against serious dangers from bacilli that are removed from the lungs by the dust-clearing cell mechanisms

Dec 1, 1916

By Richard J. Robbins

Mechanical moles have developed through a tedious process of evolution. At times it has seemed that tunnel borers have been subject to the same Darwinian rules of evolution as their zoological namesakes who, despite their efficiency, are highly specialized and still restricted to soft soil conditions near the surface of the ground. HISTORICAL HIGHLIGHTS The Robbins Co. began its work in this field in 1947 with the development of a twin-bore continuous coal miner. Although these machines were used primarily in coal, two of the early prototypes were used to bore tunnels through shale. Disk cutters were first used on these machines and showed promising results as core breakers between drag-bit kerfs. In 1953, James S. Robbins and Assocs. undertook the development of a 25-ft 9-in.-diam circular tunnel borer for Mittry Construction Co. to be used at Oahe Dam in South Dakota (Fig. 1). This is believed to be the first rock tunnel-boring machine built since the end of the 19th century when short sections of the Channel tunnel were successfully bored in chalk from both the English and French shores. Another Oahe Dam machine was built in 1955, and then a series of three small-diameter machines for the company's first real experience with medium-hard and hard rock (Fig. 2) None of these three could be considered a success, although they laid the groundwork for the success that followed. Interbedded shale and limestone in Pittsburgh and hard limestone in Chicago quickly pointed up the weaknesses in these machines which were used by Perini, Dravo, and Healey. Among the problems were the high breakage rate of tungsten-carbide drag bits, too much flexibility in the drive shafts, failure of high-pressure hydraulic systems, chain-conveyor failure, and general lack of rigidity and strength. In 1956 another attempt at medium-hard and hard rock-boring proved this time to be a success and a significant turning point in the development

Jan 1, 1970