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By W. J. Kroll

The production of beryllium metal and its alloys is one of the most difficult tasks in metallurgy. In this report we shall examine the progress made in this work- in the last 15 years; taking into account the outstanding publications, including; those of the patent literature, and the information obtained during our 20 years? experience with this metal. The difficulties experienced' in producing elementary beryllium derive from the physical nature as well as from the chemical behavior of the metal and its compounds. Its oxygen affinity is about the same as that of calcium and a little higher than that of magnesium. Its chlorine affinity is much lower than that of magnesium, about equal that, of manganese, and little higher than that of aluminum. The sulfur and nitrogen affinity is probably almost the same as that of calcium for these elements, and beryllium carbide is probably more stable than aluminum carbide, A14C3. The intermetallic affinity of beryllium may be given in descending order, as follows: Nickel - copper - iron. It forms eutectics with -aluminum and silicon as well as with silver. It does not alloy with magnesium and only partly with calcium. Its oxide melts at 2,570° C., but CaO and BaO form readily fusible eutectics with BeO(65).3/ No igneous solvents are known for BeO, which behaves id this regard like Mgo. The beryllium silicate is a strong compound, the aluminete much less so; however, CaO easily displaces Be in the heated mixtures. The Anhydrous chloride hydrolyzes, and it cannot be made from aqueous liquors. It sublimes at 488° C, and melts at 405° C., The fluoride, which, is very Soluble in water, hydrolyzes also, but a kind of oxyfluoride of the approximate formula 2 BeO?5 BeF2 can be made from solutions by dessication. The fluoride melts at 800° C, and boils above 1,100° C. It forms very stable double fluorides with alkalifluorides, which have very low melting points and are fairly soluble in water. They are more stable than the analogous fluosilicates and the sodium fluoaluminate cryolite.

Jan 1, 1945

By Michael W. Lewis

The latest downturn in the world’s metal prices has forced many mining companies to focus on cost reduction and productivity improvements to remain competitive. Maintenance represents a significant part of the overall operating costs in the mining industry. A structured, proactive maintenance approach, such as reliability-centered maintenance, can achieve cost reductions and productivity improvements. Remote condition-monitoring systems are becoming commonplace because they have the potential to identify problems before failure. Detection of equipment degradation before failure will enable repairs to be scheduled, thereby reducing costs and interruptions to production. The mining industry is in the midst of uncertain times. Decreasing commodity prices, demand, head grade and capital availability along with increasing environmental requirements have put pressure on mining companies to significantly reduce costs to maintain short- and long-term viability. Corporations are looking at expansion, merger/consolidation and financial/hedging programs to achieve these cost reductions. Mines are reducing costs by eliminating all but essential expenditures, increasing production levels, reducing overtime and investing in new technologies.

Jan 1, 2000

By W. C. Lacy

It is the responsibility of educators to look ahead and prepare young engineers and scientists to cope with industrial and social problems of the future. We are faced with a review of history as well as prophesy of the future. The mining industry exists in a "bubble" with little interaction or communication with the outside. This isolation must be broken down if the industry is to survive in the U.S. and Canada. The ability to communicate with the general public and public officials is essential. Many changes are occurring that will require readjustments in technology and staffing. Aging population will result in raising retirement and increasing available workforce. This may force shorter working weeks to supply additional jobs. Environmental concerns will likely direct more attention not only to these concerns during mining, but to planning for post-mining land usage. Retraining and up-dating educational programs are required to cope with these changes.

Jan 1, 1994

By Irving Wender

The oxo reaction consists of catalytic conversion of olefins by reacting the olefins with CO and H2 (water gas) to aldehydes that contain one more carbon atom than the starting olefin. The aldehydes are then generally reduced with hydrogen to primary alcohols in a second stage. The two-stage process is called the oxo process. The word "oxo" is derived from the German "oxierung" (ketonization); thus the exact English equivalent of "oxo" is "keto". The oxo process may be applied to nearly all olefins. A wide range of pressures and temperatures may be used in both stages. The pressure range usually employed is 150 to 200 atmosheres. The temperature in the first stage is usually about 140° C. and in the second or hydrogenation stage about 180° C. Although a standard Fischer-Tropsch catalyst may be used for both steps, cheaper catalysts have been utilized to effect hydrogenation of the aldehydes. Most of the information for this, report on the oxo process was gathered from Technical Oil Mission microfilms. T.O.M. Reels 14, 55, and 134 were especially valuable. T.O.M. Report 6 by H. M. Weir was very helpful. Information on the oxo process is scattered throughout documents captured in enemy territory, and the present report does not include all the available data. Some of the information was procured by personal interview. Where, in the body of this report, certain investigators are quoted, the source of the statement is either personal interview or the T.O.M. reports.

Jan 1, 1948

By J J. Robinson, B N. Noller, D M. Franks, G McIlveen, D R. Mulligan, A T. Soro

Fiji is a developing nation that relies on economic opportunities and recently experienced increased interest in mining and mineral exploration that could potentially benefit the country. In order to understand the lack of, or failure of, past rehabilitation activity, this study applied risk-based approaches to identify the significance of activities or actions applicable to rehabilitation of post-mined land in Fiji. This involved the use of qualitative, semi-quantitative and quantitative risk methodologies, which allow assessment and evaluation of mechanisms of mining administration and practices, as well as rehabilitation methods and approaches that have been applied successfully to post-mined land in other countries with similar environmental and climatic conditions and social and regulatory environments to Fiji. The semi-quantitative risk-based technique followed an earlier approach applied for mine closure by Laurence (2006) and provided a systematic way to assess and evaluate rehabilitation issues that were identified on-site by assessors, who were able to estimate through expert judgement the likelihood and consequences based on conditions, situations observed and circumstances on-site. It demonstrated that experienced professionals could reproducibly score likelihood and consequence of selected items relevant to mine site rehabilitation, despite the wide-ranging issues identified during post mined land rehabilitation. The quantitative risk-based approach was adopted as a method to determine environmental bonds for mining projects using the assessment of consequences and likelihood results from the semi-quantitative approach, then incorporating unit cost of materials or activities for local conditions required to fully rehabilitate each issue at net present value. Application to both an abandoned mine site and a newly opened mine site in Fiji showed that this approach could provide a risk-based estimate for rehabilitation cost and demonstrated potential applicable in the Fijian context.CITATION:Soro, A T, Mulligan, D R, McIlveen, G, Franks, D M, Robinson, J J and Noller, B N, ?2014. Risk-based Rehabilitation Strategies for Post-mined Land in Fiji, in Proceedings Life-of-Mine 2014 , pp 165–180 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 16, 2014

By George Innes

The soda ash business in the United States has undergone a sweeping technological change in ihe last 20 years. In a world where synthetics are continuzlly replacing natural products, here we have exactly the opposite, a syntheric chemical being replaced by a natural product. This change is nearly complete in the U.S. and is beginning to take place in Europe and other parts of the world.

Jan 1, 1980

By Grey CA

Any economic evaluation of a lead-zinc mining project requires the estimation of net revenue per tonne of concentrate at the "mine gate". The value at the mine gate equals the Net Smelter Return minus all realisation costs. The paper develops a simple predictive model for Net Smelter Return based on metal prices.

Jan 1, 1990

By Paul Hatmaker

This paper covers briefly the particular field of dolomite and magnesium limestone; certain uses of high-calcium limestone are mentioned only to show more clearly the limita¬ tions of the magnesian rocks. Such a comparison is helpful because magnesium carbonate is essential for some uses; for others it is immaterial; and for many its presence in an appreciable amount is objectionable. Magnesium carbonate, occurring as a rock resembling limestone or dolomite, is described in United States Bureau of Mines Information Circular 6437, Magnesite. Other com¬ pounds of magnesium are described in United States Bureau of Mines Information Circular 6406, Magnesium Compounds (Other Than Magnesite). Limestone, geologically, is a rock composed essentially of calcium carbonate; commercially, however, the term may include dolomite and magnesium limestone.

Sep 1, 1931

By William Gates, Gabe McClain, Thomas Pallua, Joe Schrank

The Tennessee Capitol Corridor connects the Cordell Hull Building (CHB) to the State Capitol, which isa 232-foot-by-124-foot (71 x 38 m) structure in Nashville that includes porticoes built from local massive limestone. This connection was affected by the Capitol Connector Pedestrian Tunnel (CCPT) project, which is part of the overall Cordell Hull State Office Building and Central Services Demolition, New Construction and Renovation Project (Cordell Hull Renovation Project). To construct this connection, the two existing elevator shafts and a new emergency stairwell in the State Capitol were extended down to anew lobby area—the elevators by about 50 feet (15.2 m) and the stairwell by about 60 feet (18.3 m). This lobby was connected to the CHB by a 435-foot-long (133 m) pedestrian tunnel. It was predicted that most of the tunnel would be excavated in a relatively strong limestone; therefore, considering the project features and constraints, drill-and-blast techniques were selected as the primary excavation method. Because of restrictions on blasting in urban areas and, more importantly, the proximity of this construction to national historic landmarks, blasting operations were extensively monitored to measure and correlate ground vibrations as peak particle velocity (PPV), frequency, and strain—these being the major factors that would impact the surrounding buildings. As a result, copious amounts of data were gathered and interpreted within a short time to estimate blasting parameters and optimize the subsequent blast rounds. To calculate the ground response factor, the scaled distance of each shot was compared to the ground vibration as PPV, generating a subsequent regression curve with an R2value of about 0.7. Using the best fit curve equation, the estimated ground response factor was about 150 for the best fit line. Other than some cases with relatively high (> 2 in./sec [51 mm/sec]) recorded PPV values, the blasting operation was successfully conducted as planned and the observed strain on the monitored buildings was very low, mainly within ±2 με (0.0002% elongation). (In general, the recorded PPV was lower than 2 in./sec at frequencies of more than 50 Hz.). The strain gauges at key locations (cold joints and old fractures) in the Capitol and on other critical structures demonstrated strain was insignificant in relationship to ground vibrations from the blasting operations. The apparently small vibration-induced strains were related to the massive limestone construction of the Capitol and ancillary buildings, as the induced strain plus the existing strain did not exceed the critical strain of the massive structures.

By N. Loganathan, Tan Boon Tee, Joe O’Carroll, Richard Flanagan

In recent years, tunnelling activities in Singapore have increased considerably with the construction of extensions to the existing sub-surface transport system, a deep tunnel sewerage disposal system, and tunnels for the laying power cables and other utilities. These tunnels are excavated through urban areas, adjacent to high-rise buildings, depressed road structures, beneath other tunnels, and buried services. Earth pressure balance (EPB) tunnel boring machines (TBM) have been used extensively in Singapore with great success. The risk associated with soft ground tunnelling, including tunnelling through Old Alluvium, can be minimized with an understanding of the geology, geotechnical parameters, and the tunnelling-induced behaviour of Old Alluvium (OA The purpose of this paper is to present some design and construction aspects of EPB TBM tunnelling through Old Alluvium.

Jan 1, 2005

By Enver Alan, MerkeziYapı

People are migrating because of economic, social, natural and political reasons. These natural and humane factors effects the distribution of populations. The need for tunnels has grown in order to provide a comfortable life and reduce losses such as waste of time, labor, energy, efficiency and so on. It is inevitable to carry out excavations in rock tunnels (shears, platforms, lines, connections, wastewater, distribution, energy, transportation etc.), that will be built by excavating with conventional method, by controlled blasting regarding with constrains. In this study of applied explosives engineering the blasting applications are evaluated, which were carried out for research and development purposes at Yenisahra Station tunnels in Kartal Formation which was built with the aim of solving İstanbul's transportation problem within the framework of the Kadıköy-Kartal Metro Project. Twenty-four shots were made by using explosives in 60 blastholes that were drilled in the tunnel faces, which were located between and outside of two different faults. Six microphones were used to measure the air shock and eight geophones were used to measure the parameter values of the vibrations (particle velocity, frequency, displacement, acceleration, amplitude, wavelength etc.), which were placed at predetermined points of the surface, occurred during the blasting applications. Data from the geophone and microphones were recorded on six seismographs. The coordinates and the distances between the shot points and the measurement stations are determined by an electronic theodolite. The total number of seismic records, recorded in seismographs, is 118. The number of records of vibrations that crossed the faults is 42 and the number of records of vibrations that did not cross the fault is 76. The particle velocity, frequency, amplitude, acceleration, displacement and wavelength were measured in transverse, longitudinal and vertical directions. The total number of measurements is 354. By evaluating all seismic records, the effect of delay intervals, faults and scaled distances on the particle velocity, frequency, amplitude, displacement, acceleration, wavelength and air shock were investigated. When the vibrations formed during the Research & Development (R&D) blasts were examined, it was determined that the parameter values of vibrations that crossed the faults are lower than the ones that did not cross the faults. In addition, when the particle velocity values of all vibrations are examined according to the present circumstances, it is determined that the waves did not cross the fault in all delay intervals are superposed in all directions, and that the least superposing occurred in the 50 ms delay range.

By K. K. Kelley

This work is both a revision and an elaboration of Bureau of Mines Bulletin 371, which was published in 1934 and included data available to October 1933. During the intervening years, a large number of new experimental, high-temperature, heat-content data have become available through continuous, systematic efforts of the Pacific Experiment Station of the Bureau of Mines and the Laboratory for Inorganic and Physical Chemistry of the University of Groningen (Netherlands), coupled with various individual investigations at many institutions. In addition, calculations from spectroscopic and molecular constant data have been extended and applied to a wide variety of gaseous substances. This bulletin purposes to collect and correlate all available high-temperature heat-content and specific-heat data for inorganic sub-stances and to formulate tables and algebraic expressions for their representation. It is hoped in this manner to remove some of the tedium of thermodynamic calculations for industrial metallurgical research workers and engineers who often have available only an inadequate library in this field. It is expected also that this bulletin will have value to those teaching courses in metallurgical and chemical thermodynamics.

Jan 1, 1949

By A. R. MacLean

This mine is situated at Point Aconi, Cape Breton , Nova Scotia, and is a replacement for the 100-year-old Princess Collie ry. It is a slope mine which is the continuation of a s trip mine operation. There are fives lopes from the surface driven with Dosco Dintheaders - this marks the first time these machines were used in North America. There are four room -and-pillar sections, each equipped with a Lee Norse HH106 continuous miner, a "Top Dog" roof bolter and two Wagner diesel Teletrams. There are also two Eimco 913 diesel LHD's , which are used for clean-up in the mines. This paper describes the mining operations of this 800,000-tpy mine which, in less than a year and a half , has been developed to the stage where four sections are producing coal at the desired rate.

Jan 1, 1978

By R. P. Goel, P. N. Chaudhary, R. K. Minj

The bulk of high carbon ferromanganese produced in India continue to have more than 0.35% phosphorus since they are produced by carbothermic reduction process. The low phosphorus manganese ores are depleting fast and ferromanganese manufacturers will have no option but to use medium and low grade ores having high phosphorus content resulting in high phosphorus in the product. A systematic study was taken up at NML to solve this problem. Initially, a thermodynamic analysis was carried out for which Ba-P-O ternary predominance diagrams were constructed at several temperatures to predict the most suitable conditions for selective removal of phosphorus from high carbon ferromanganese. These conditions required a usage of a flux having a high level of basicity, moderate oxygen potential as well as low melting temperature. The experimental results showed that it was possible to remove phosphorus from high carbon liquid ferromanganese from 0.56%to 0.18% using BaCO3 based fluxes at the rate of 16-wt% of the ferromanganese charged. However, the Mn loss varied in the range of 2-5%. The objective of the subsequent study carried out at the laboratory scale was to optimize the flux consumption as well as minimize the Mn loss with effective dephosphorization by using BaO based calcined pellets instead of BaCO3 based powders. It was felt that the handling of pellets under plant conditions would be easier and also eliminate the loss of flux as a dust, which occurs when powder is added. These pellets were forced towards the bottom of the melt for better efficiency. For this purpose, a plunging system was designed and fabricated in-house that helped in reducing the flux consumption to less than 5% and also improved the kinetics of the process. The desired results were achieved within 10 minutes of the addition of the flux. The know-how is ready for transfer to interested parties and authors are willing to conduct large scale trials with them.

Jan 1, 2007

By Paulo Ricardo Bastos de Queiroz

Após estudo realizado, verificou-se que a CSP - Companhia Siderúrgica do Pecém, possuía alta vulnerabilidade às oscilações de frequência, sejam elas oriundas de falhas nas unidades geradoras ou problemas nas linhas de transmissão que compõem o SIN (Sistema Interligado Nacional), onde tais perturbações poderiam provocar desde a parada total da planta a danos irreversíveis em equipamentos como motores síncronos. Com base nesse estudo, foi implantado um sistema automatizado e de rápida resposta capaz de diminuir ou eliminar todos os efeitos provocados por tais distúrbios, atuando de forma dinâmica e coordenada com o cenário energético ao qual a planta siderúrgica encontra-se no momento do evento. Dentre os ganhos apontados em estudo, destaca-se a confiabilidade de se ter um sistema de distribuição de energia em uma usina siderúrgica capaz de assegurar a continuidade do processo ou em piores casos proporcionar uma parada emergencial com total segurança.

Oct 30, 2017

By J. A. Herbst

In spite of potential theoretical and economic advantages of large-diameter ball mills, many manufacturers elect not to build these mills owing to what is perceived as an excessively large design risk. This risk results from the fact that traditional predictions for mill-scale-up to large diameters are not always accurate. It is apparent that alternative methods of analysis and scale-up are required. Recent studies have shown that detailed population balance models which account for important grinding subprocesses, i.e., grinding kinetics, material transport, and classification, are capable of predicting the performance of small- and intermediate diameter mills (up to 4.3 m (14 ft)) from small-scale batch tests. These same models are used in the current study to predict the performance of a "borderline" large ball mill (4.7x5.5 m) at Asarco's Sacaton operation, a ball mill (5.0x5.8 m) at Kennecott's Chino operation, and one of the world's largest ball mills (5.5x6.1 m), at Cities Service Pinto Valley operation. Model parameters required for scale-up have been estimated in a 380-mm diameter batch mill. Predictions are compared with the results of detailed plant sampling in the three plants. For the Sacaton and Chino operations, the error of the predictions was found to be less than 2.5%, while the corresponding error for the Pinto Valley operation was less than 2.7%. It is concluded that proper representation of the major subprocesses of grinding in the model equation is the key to achieving accurate scale-up. Of special importance is the need to account for the size distribution of the grinding media and the influence of the size distribution environment in the mill on grinding kinetics.

Jan 1, 1983

The Bureau of Mines has reviewed those portions of the "Tariff Schedules of the United States Annotated 1963" that are of interest to the minerals industry. This study shows to what extent rates of duty were altered (increased of decreased), and provides a bridge where possible from the old Schedule A classification system to the new TSUS system of statistical reporting of import data. In general the new tariff has corrected previous classification defects and inconsistencies, but the rates of duties have not been materially changed.

Jan 1, 1965

By Bonifacio Degay, Mike Lovitt

PT Freeport Indonesia is a block cave mine that now utilizes an advanced undercut method to set up the min in the Deep Ore Zone (DOZ). In this method a slice of rock (undercut) is broken such that it sits on top of the drawbell level. The drawbells are developed to channel the broken ore into the extraction level and to enable the caving orebody to be drawn out in an even and controlled manner. These drawbells are difficult to form due to the small amount of void that can be developed in the low strength rock before firing. Starting with two rises of 2m square, the void ratio for the entire drawbell around 6%, which would normally result in a frozen and unproductive blast. Orica -Mining Services have worked with PT Freeport in a collaborative effort to find a solution to the mining problem. With excellent control of timing of the blasting it is possible to get fluid flow of blasted rock out of the draw points such that more void can be made available for blasting the remaining parts of the drawbell. The i-konTM electronic blasting system gives the exacting control of timing within the blast to achieve this Dynamic Void Generation (DVG). The solution stops the need to charge close to brows in the drawbells and reduces the cost and time related to developing initial blast voidage. This paper identifies the results of the trials including design, photographic evidence and vibration analysis. The flexibility and accurate timing of this electronic blasting system has enabled single hole initiation rather than 4 or more holes being initiated together, thereby reducing the damaging vibrations to the extraction level.

Jan 1, 2004

By E. Bonsall, J. J. Brummer, A. R. Graham

"A method and device are described for sampling diamond-drill core by cutting a continuous fillet of constant cross section from the cylindrical surface of the core throughout appropriate sample lengths. The apparatus employs a tapered, abrasive-set, cutting wheel, the conical cutting surface of which projects slightly into a rectangular core-guiding trough set parallel to the axis of rotation. The depth of fillet and thus the amount of sample per unit length can be regulated by adjusting the core guides. The freshly cut fillet itself, by engaging in a guide beyond the cutting wheel, acts to prevent rotation of the core during operation of the device.The cuttings which form the sample are normally collected in a tray below the cutting-wheel and appear at about 80 per cent -100 mesh. They require little or no further treatment or comminution before analysis. Speed, economy and convenience of sampling are thus greatly increased as compared with conventional sampling by im-1>act breaking or sawing, followed by crushing, grinding and sub division for assayAssays from fillets (about 1/20 the cross-sectional area of the core) and from 180-degree segments, from the same ninety-three core-samples, representing 431 feet of nickel-copper mineralization, gave the following results:"

Jan 1, 1968

By McNicol M. D

Petroleum exploration in onshore Gippsland was directed in the 1950s and 1960s towards plays in the basal Latrobe and Strzelecki Groups, but these became forgotten in the 1970s with the Latrobe play discoveries offshore. The principal explorationists of the time were Woodside Oil and Arco Ltd, who then departed the scene after drilling some 18 wells without major success. In the late-1980s successful hydrocarbon finds in equivalent age Otway Group sediments in the Otway Basin were made and in early 1990 Tyers Petroleum began investigations into Strzelecki Group prospects as applied to the onshore Gippsland Basin. Some 18 anticlines have been mapped, based on shallower coal exploration drilling in the Latrobe Group, which from seismic and gravity evidence are believed to unconformably overlie similar anticlinal structures in the underlying Strzelecki Group. Strzelecki targets of interest within drilling depth are the basal Tyers Conglomerate/Rintouls Creek Sandstone Formations which outcrop in the north of the Latrobe Valley and are analogous to the Pretty Hill Sandstone in the Otway Basin. In addition, intra-Strzelecki Group targets similar to Heathfield and Windermere Sandstone Members are also considered to be present. Good source rocks are abundant including coal seams and carbonaceous sediments of Neocomian and Jurassic age, which lie within the oil window. Seal is provided by the overlying Aptian-Albian aged volcanogenic sediments. The Tyers/Rintouls sandstones - a target in the Woodside/Arco wells, with two exceptions, were not reached. Encouraging intra-Strzelecki shows were reported in many of the wells. Basal and intra-Strzelecki porous quartzose sandstones remain one of the few untested plays left in the Gippsland Basin and, in the onshore, merit extra attention as they he within the oil window at economically drillable depths.

Jan 1, 1992