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By E. E. Creitz

Application of the usual chemical methods to the determination of beryllium in the mineral-dressing products of a spodumene pegmatite was found to be unsatisfactory as to speed, accuracy, sensitivity, and range of analysis. A spectrographic method is described for the determination of beryllium. Samples are ground, mixed with borax, high-purity, flake graphite, and an internal standard; then they are fused, reground, pelletized, and excited with a high-voltage-spark discharge. Investigation of several spectrographic techniques to overcome matrix effects are described. The method developed gives results for beryllium in the concentration range from 0.002 to 5.0 percent; the average probable error of duplicate determinations was below 3.0 percent of the quantity present. INTRODUCTION The main source of beryllium in pegmatite is the mineral, beryl. Many of the conventional methods for the determination of beryllium in beryl are not suitable for control purposes because of lack of speed and accuracy, especially in the range below a few tenths percent. Beryl resists the usual chemical attack and can be lost in a hurried chemical analysis.

Jan 1, 1958

By James H. Aase

[This study provides data on the physical and hydrological makeup of the ,t hakes waterway system and forecasts quantities, traffic patterns, and ping cost of prospective bulk mineral commerce projected to be transported it. Factors affecting the shipping cost of iron ore, bituminous coal, imestone were quantified and integrated into a computer program that can d to estimate costs under varying sets of conditions. Combined ship of iron ore, bituminous coal, and limestone in 1995 were estimated at million tons. The cost of operating the U.S. vessel fleet for trans-ng an indicated 80 percent of this traffic tonnage was projected to be $163. 5 million.]

Jan 1, 1970

By H. B. Brunot, L. C. IlsLey, E. J. Gleim

"INTRODUCTION To supply inspectors, safety engineers, and others with detailed information as to the safety features of the various electrically operated machines that have been approved as permissible by the Bureau of Mines, three bulletins and five reports of investigations have been published dealing with the various classes of approved machines:Bull. 313, Permissible Storage-Battery Locomotives and Power Trucks.Bull, 343, Permissible Coal-Handling Equipment Approved from January 1926 to December 1930, inclusive.Bull. 382, Permissible Coal-Cutting Equipment Approved Prior to July 1, 1932.Rep. of Investigations 3309, Permissible Electrically Operated. Air Compressors.Rep. of Investigations 3326, Permissible Electrically Operated Room Hoists.Rep. of Investigations 3345, Permissible Electrically Operated Rock-Dust Distributors.Rep. of Investigations 3363, Permissible Electrically Operated Hand-Held Coal Drills.Rep. of Investigations 3391, Permissible Electrically Operated Post Drills and Drilling Machines.The present paper gives similar information relative to the mine pumps approved before October 1, 1939."

Mar 1, 1940

By Rachel Bauer, Jacob Henderson, Dr. Catherine Johnson

Capital Quarries in Owensville, Missouri faces several challenges when designing a blast that allows for ease of movement while maintaining controlled throw and compliant air over pressure. The primary challenge is the nearest non-owned structure (NNOS) is a residential home located 250 feet from the quarry. Another challenge is a production bench which is 100 feet tall and separated from the NNOS by Pennsylvanian fire clay that filters out high frequency waves from the blast. Material from the blast must also be less than 5 inches in order to be processed by the crusher in the quarry. To provide as much relief as possible, production shots will consist of a single row with the minimum required burden. To design the shot, signature hole analysis was used to determine the optimal timing between powder columns. Electronic detonators provided an accurately timed shot to minimize the amplitude of the vibrations while maximizing the frequencies. Boretraking and 3D profiling with Renishaw laser profiler and Strayos drone photogrammetry provided an accurate burden measurement. Powder factor was kept at 1.3 tons/lb using bulk emulsion. The boreholes were split into 5 powder columns with the top of the hole firing first in order to blast to floor grade. The resulting shot produced good fragmentation and shot to floor grade. Seismograph readings showed air over pressure vibrations within legal limits. Due to this success, multiple shots will be designed using the process described.

Feb 6, 2023

By G. Mousavian, R. Bagheri, N. Dalili

Polypropylene (PP) and its composites have an increasing use in automobile and domestic industries. Since the published results on strain rate effect on yield behavior do not match, and there is a high attention paid for effect of nanometeric fillers on deformation behavior of composites, in this research the strain rate effect on yield behavior of PP and the effect of nanometeric fillers on deformation behavior of PP have been studied. Microscopic observations and tensile tests in different strain rates on neat PP samples and on samples filled with 5, 10 and 15 %wt have been used. A dramatic change in behavior for the modulus and post-yield slope curves when the strain rate is between 0.0433-0.05 s-1 has been observed. Microscopic observations on PP indicate a change in deformation mechanism from shear yield to crazing at the same strain rate that the change in behavior of curves occurs. It has been observed that in PP nanocomposites with higher amount of calcium carbonate, fracture in early stages of deformation occurs in lower strain rates. In other words for a fixed stain rate there is a critical filler percentage such that if the filler percentage is higher then early-stage fracture will occur. Similarly for a fixed filler percentage there is a critical strain rate and in higher strain rates early fracture will occur. The critical stain rate will decrease as the filler percentage increases and vice versa.

Jan 1, 2006

By AIME

The Taconites Are Ready, the editorial appearing on P. 933 of the September issue, has provoked comment from several informed engineers to the effect that the indicated profit margin was considerably exaggerated. The cost figures in the editorial, taken from the Congressional Record, were characterized as inaccurate by some correspondents. The theme of the story was, however, substantiated in the announcement (P. 1023, October) that Republic and Armco had joined forces in a $160 million project for taconite development. Chief among the dissenters was E. W. Davis, , Director of the Mines Experiment Station at the University of Minnesota. Mr. Davis has worked up the following set of cost figures:

Jan 1, 1950

By R. L. Every, A. G. Fonseca

"Sulphur deposition on the internal wall of a pipeline is caused by the temperature effect on the solubility of sulphur in the carrier fluid and is not due to particulate sulphur present. Deposition can be completely eliminated by proper insulation of the pipeline to prevent ""cold-spots"" and the resultant temperature gradient necessary for sulphur to precipitate from solution. Friction head losses for sulphur-condensate slurry systems are quite acceptable from a technical and economic standpoint and, in fact, are less than many present commercial slurry systems. Slurry transportation of sulphur in a hydrocarbon pipeline is a viable possibility and promises to have economic advantage over currently accepted transportation modes."

Jan 1, 1972

By A. C. Lordi

Present industrial plant design is influenced by motivators beyond the usual powerful one, creativity, on which Consultants thrive. The respected, although annoying, ever-present Return on Invested Capital becomes even more significant with anticipated escalation. Government regulations are having an increasing influence as air and water protection, sound and electrical safety requirements must be met And more recently, the increasing cost and uncertain availability of energy sources are having a revolutionary affect on plant design. More than ever before, the Consulting Engineer is faced with requirements and restrictions which tax even the most original thinkers -- and the result is good. This paper includes a brief review of recent trends in Cement Plant Engineering Design.

Jan 1, 1975

By David Mitchell, Daan Delport, Frik Marx, Mike Shapiro

The use of copper cooling elements to enhance refractory lining life in pyrometallurgical vessels is common in modern furnace design. Copper elements typically incorporate a base panel with cast in cooling passages and an integral extended surface (formed of pins, fins or similar) onto which suitable refractory material is cast. The metallic, conducting parts are located towards the cold face of the lining, with the refractory material interposing between the coolers and the process. The coolers are designed to arrest wear of the refractory material by freezing a layer of slag or partially reacted material onto the hot face, thereby rendering the lining inert to further attack [1]. These coolers have achieved success in new furnaces and relining of existing vessels. The freeze layer is prone to mechanical damage during operational and process instability. The coolers must be capable of extracting the additional heat flux under upset conditions to facilitate rapid self-repair of the freeze layer and prevent further refractory wear in the intermittently exposed areas. However, operational experience has shown that the high heat flux capabilities of the copper coolers have some disadvantages, especially in processes producing vapours which form corrosive compounds when condensing onto the cold surfaces of the coolers. When corrosive conditions develop, the entire composite will fail due to loss of structural integrity, and as a result of leaks from the cooling water passages. This paper describes recent developments in the approach to the design and manufacture of copper cooler panels customized to achieve specified heat fluxes and temperature profiles, thereby reducing the formation of corrosion mechanisms in applications with corrosive gaseous environments and enhancing refractory lining life. Condensation formation prevention is achieved by adjusting the geometry of the cooler and selection of suitable materials of construction.

Jan 1, 2007

By C. Gasparrini

Mineralogy may be applied to the selection of appropriate separation techniques, as well as to assist in the evaluation of problems causing loss of metals and other economically important elements during plant processing. Mineralogic studies may thus help develop techniques to optimize metal recoveries. The present paper describes how such factors as the minerals in which the elements of interest are concentrated, their chemistry, the chemistry of the associated minerals, grain size and textural associations with other minerals in the ore, may affect decisions on separation techniques for the recovery of economic elements. A number of case studies are described in which the mineralogical observation of ore samples has revealed the cause of problems experienced in the extraction of select precious and base metals, or has been decisive in the choice of appropriate techniques for recovery.

Jan 1, 1981

By J. A. Lepinski

The FASTMETSM Process is a coal-based process for converting iron oxide fines into metallic iron. The end product, direct reduced iron (DRI) is used as a low residual charge material in electric arc furnace steelmaking. This paper describes the FASTMET Process and its potential application in the United States. Operating results from a 175 kg/h process simulator are presented. Characteristics of the end product are discussed. Process economics are reviewed along with plans for scaling-up the process to full commercial size.

Jan 1, 1993

By William R. Yernberg

Most citizens take it for granted, but minerals produced in the mines of the western United States, including Colorado, are crucial to nation’s standard of living and quality of life, said Colorado’s Gov. Bill Owens in his welcoming remarks at the 106th National Western Mining Conference. The conference, which was organized by the Colorado Mining Association (CMA), was held Feb. 4-6, 2004, in Denver. Attendance was425, up substantially from last year’s meeting. The meeting included the CMA annual membership meeting as well as the CMA chairman’s and president’s reports. The meeting also included awards presentations in which companies were recognized for their efforts in pollution prevention, health and safety, and reclamation. The conference also included a tradeshow.

Jan 1, 2004

By A. B. Hooker, R. A. Kearns

Material used for flame safety lamp gauzes should possess the following qualities: (1) mechanical strength, (2) resistance to corrosion under service con- ditions, (3) a relatively high thermal conductivity, (4) a melting point above the ignition temperature of mine gas. Heretofore, three metals have been used for flame lamp gauzes, namely: steel, brass and copper. While each of these has the requisite qualities to some extent, none of them is an ideal gauze material. Copper gauzes lack mechanical strength, especiall, after they have been heated; brass and copper both have comparatively low melting points so that before the gas ignition is reached the gauze metal is attacked and oxidized under the action of the heat. Steel corrodes readily in damp atmos- pheres and if the lamp stands unused under these conditions for some time, the gauzes become unfit for service. Tests of these three materials have shown that steel offers the highest degree of safety. Manel metal, the natural alloy of nickel and copper, is practically noncor- rodible. Its relting point is approximately the same as that of steel. From time to time it has been suggested that this alloy might be a better gauze material than steel, since gauzes made of Monel metal should have all of the good qualities that steel gauzes possess and, in addition, would not corrode appreciably in ordinary mine atmospheres. One advocate of this use for Monel metal, the International Nickel Co., through their development engineer, Mr. Robert J. McKay, cooperated with the Interior Department, Bureau of ines, to the extent of supplying twelve sets of 30 mesh, Monel-metal gauzes for tests. Those gauzes were made up by the same lamp manufactur- er ho rade the steel gauzes used in the previous investigation. Being made by the same processes as the steel gauzes, these Manel-metal gauzes were needlessly given the same anti-rust coating that is always applied to steel gauzes to prevent any corrosion before the gauzes are used. In previous tests the Bureau of Mines had collected data as to the behavior of steel gauzes. In determining the value of Monel metal as a gauze material, it was planned to obtain similar data with Monel-metal gauzes, and thus make a direct comparison with the steel gauzes. In addition, steel and Monel-metal gauzes

Apr 1, 1923

By Pedone Ezio Michele, Mohamed Dahir Holad

"The 4c segment is a part of the ""Oman National Railway Project” linking the mining area in the surroundings of Thumrait and the port of Salalah. It is 90 km long and the last 40 km stretch crosses a mountainous area near the city of Salalah. The project includes the excavation of a 33 km double and single bore tunnel and 10 km of safety tunnels. This mountainous area is a holiday destination for Omanis, thanks to its beautiful landscapes, especially in summer time due to the monsoon rains. The tunnelling design had to take into account both these environmental constraints and the limestone rock formations crossed, which are affected by significant karst features. Given the context, the conventional tunnelling method has been preferred. INTRODUCTION The Oman Railway Project (Fig. 1) covers the construction of approximately 2,150 km of railway line for freight and passenger transport which will connect together Oman’s main towns and industrial sites and it will form part of the Arabian Peninsula railway system “GCC Project”. The non-electrified double-track railway line must guarantee a speed of 220 km/h for passenger trains and 120 km/h for freight trains and must guarantee the transit of AAR (Association of American Railroad) H and D plates using clearance envelope according to AREMA (American Railway Engineering and Maintenance-of-Way Association) requirements. The design alignment must have maximum radiuses of curvature of 3,250m and a maximum gradient of 1.0%. The project is divided into 9 constructional and functional segments. •,Segment 4c will be constructed in the southern region of Oman, close to the border with Yemen, to connect the town of Thumrait with the Port of Salalah. •,Segment 4c will run through the Dhofar region and will be mainly used by the freight traffic which currently travels by road."

Jan 1, 2016

By T Baumgartl, D Mulligan, R Haymont

Mining at the Mt Leyshon Gold Mine in semi-arid north Queensland stopped in 2002. Newmont Australia has recently initiated a thorough post-closure water management study of the site by revisiting the existing information and conducting new water-related investigations. The focus of this paper, which is the first publication on post-closure environmental management of the site, is an overview of the site water quality in view of the sources and spatial distribution of polluted mine water, and also the performance of cover systems in controlling water flux though mine wastes. Since the mine closed the rehabilitation of waste rock dumps and tailings dams have significantly improved water quality in the surface receiving waters. However, the Scats Stockpile, the Heap Leach and Old Plant areas, which can potentially produce acidic waters, enriched with heavy metals and arsenic, are the top management priority. Modelling of the potential transport of contaminants in groundwater needs further investigations. A detailed examination of the waters in seepage sumps showed high concentrations of manganese, cobalt, nickel and selenium, which were previously overlooked. The study also showed distinctive chemical signatures for waters at different locations: the waters draining from scats, supergene materials and waste rocks have distinctly lower pH and higher concentrations of dissolved iron, sulfate, heavy metals, Mg, Mn, U, Se and As. While, the tailings sumps are more alkaline, and are enriched in Na and Cl. The southern tailing sump is characteristically As rich. The waters draining from the supergene materials have higher Cu concentrations. Assessment of the cover monitoring systems showed that although covers pass the design criteria, automated recording of data may ignore any failure of the monitoring system. Recalibration of the moisture sensors not only showed realistic moisture values compared to rainfall data but also showed that the permanently installed system records values that are higher than those of the mobile system. Event-driven recording of data overlooks infiltration events. Besides, with a higher time resolution (daily measurements) the breakthroughs could be clearly detected. Modelling of the water balance in covers is underway and an example is given here. Newmont is currently reviewing water management options and is willing to share the lessons learned.

Jan 1, 2006

By Vernon C. Allison

The explosibility of coal dust has long been recognized by competent investigators as constituting one of the dangers of mining coal and in the use of pulverized coal as a fuel in industrial plants. The Bureau of Mines has carried on extensive series of experiments dealing with this subject, and has not only developed methods for the practical prevention of this danger, but in the, course of these experiments has developed a standard method of determining the relative explosibility of coal dusts and other organic dusts.3 Oil shale contains compounds 'of carbon and hydrogen that are either of a petroleum nature and are strongly ,adsorbed upon the incombustible part of the shale, or else are present in the shale as a compound ("kerogen") which has the property of changing into petroleum-like products when acted upon by heat. The oil shales may contain varying amounts of the organic matter, ranging from a trace to more than 66 per cent, depending upon their richness; therefore, it is important to know whether the dusts formed in mining and handling these oil shales are explosive when mixed with air and if so, to indicate remedial measures. This paper gives the results of explosibility tests of several pulverized oil shale's, selected as being typical of those which in the future may be used in commercial shale-oil production test on a sample of typical Colorado oil shale has been., published in an earlier paper.4

Jan 1, 1926

By W. F. Cannon

Many high-grade manganese deposits of the world occur in marine transgressive sedimentary sequences deposited on stable platforms. These include the Nikopol and related deposits in the Soviet Union and Groote Eylandt, Australia, among others. We suggest that the Atlantic and Gulf Coastal Plains and the vast area of Cretaceous rocks in the middle of North America are favorable provinces for sedimentary manganese deposits because regionally transgressive units are widespread. North America has 16% of the world's land area but only about 0.2% of known high-grade manganese reserves. This disparity is difficult to reconcile in view of the fact that large areas of North America are underlain by rocks that we consider at least broadly favorable to contain manganese ores, and we suggest, therefore, that important high-grade deposits remain to be found in North America.

Jan 1, 1982

By Rachel E. Gooding, George C. Emmett, David R. Bradley

The United States (U.S.) Department of Homeland Security (DHS) Directorate of Science and Technology (S&T) is using a probabilistic risk assessment (PRA) approach to evaluate the risks from terrorist use of explosive materials against the Homeland. A similar approach is currently being used to evaluate the risk from terrorist use of chemical, biological, radiological and nuclear materials.

Jan 1, 2017

By N. A. Sithole, S. A. C. Hockaday, P. J. A. Bezuidenhout

The Northern Cape Province in South Africa has high levels of annual direct normal solar irradiance and reserves of zinc (Zn) ores. The question arises as to the benefits of integrating renewable solar energy into the beneficiation routes of these reserves. The paper evaluates a novel flowsheet for the production and beneficiation of Zn in this region, maximising localised solar energy as a source for both electricity and process heat. Solar variability is discussed and the cost and benefits of thermal storage in the flowsheets are evaluated by its influence on the levelised costs of electricity and process energy over the project life-time at a possible implementation site. The results of the developed scoping model showed that solar photovoltaic integration to provide electricity for electrowinning without battery storage can lead to more than 10% cost saving on electricity over the lifetime of the project. Additional savings potential was identified when battery storage was included to enable the solar PV system to supply electricity during peak tariff periods. The solar thermal case showed the most promise with savings of 70% on heating costs for casting, while solar PV electricity without storage resulted in a 16% cost saving on heating for casting over the lifetime of the project. Solar PV electricity generation resulted in the avoidance of more than 20% of CO2 emissions from grid electricity use. Solar thermal heating can avoid up to 80% of the CO2 emissions associated with grid electricity use for remelting of Zn cathodes for casting. The CO2 emissions are indirect and not subject to South African carbon tax. Keywords: Solar process energy, zinc beneficiation, flowsheet evaluation

Jan 1, 2020

By Samuel Tescher

The operation of gaseous mines is a problem, due to the fact that we have not only the ordinary mine accidents to guard against, but have also the ever present menace of a mine disaster involving a large number of human lives, and the destruction of valuable property. In looking over the reports of mine disasters throughout the country in the past several years, we find that methane gas, coming in contact with an ignition agency of some kind, has been the source of at least 75 per cent of our mine explosions. Coal dust, of course, plays its part in propagating the explosive action throughout the mine workings and rendering it more violent and destructive; nevertheless, the initial ignition of a body of explosive gas-sometimes of very small volume-has been the primer for the large majority of our mine disasters. We find also, that the places of initial ignition are most frequently found at the working faces, or in close proximity thereto. This is mainly due to the following reasons: First-The working faces are, as a rule, the places where methane gas is most freely generated. Second: They are places that are most poorly ventilated. Third-They are the places where ignition agencies are most frequently found. The sources of ignition, as a rule, consist of naked lights, the shooting -of shots, defective flame safety lamps, and electrical arcs. The problem, then, in the operation of gaseous mines, is primarily to so ventilate the working faces that an explosive mixture is not likely to occur, and to endeavor to keep away from the working faces all sources of ignition. To do both of these things may seem impossible. Nevertheless, by working along both of these directions, a great many disasters can be avoided. The efficient ventilation of the working faces is paramount. By efficient ventilation, we mean the continuous passing of large volumes of air at the working faces. This can only be accomplished by adequate ventilating equipment, capable of being driven by at least two independent and distinct sources of power, together with large, clean, straight air courses which are free of short turns, constructed areas, and leaky doors and stoppings. In other words, furnish a suitable course for its travel through the mine. Many of us sharpen our pencils and rack our brains to properly estimate the proper size pump and pipe equipment that may be needed to handle a certain amount of water. We estimate the size of copper conductors to a nicety. We immediately rush to repair leaks in our water, compressed air or electric lines. But how many of us give serious thought to the travel of the air through our mines, the health and safety-giving fluid on which so much depends! In driving air courses, a certain economical cross-sectional area should be adopted and maintained as standard. When turns are necessary, they should be made with long radius curves, and the cross-sectional area should be increased on the curves. All entry stoppings should preferably be built of monolithic concrete, with suitable hitches into floor and ribs, and after the concrete has set, they should be examined and leaks due to shrinkage and settling should be eliminated. Overcasts and their approaches should have cross-sectional areas larger than the entries leading to them, to allow for the sudden change of direction, bearing in mind that air wants to travel in straight lines. In the early development of a property, ample provision should be made in the size of the main entry pillars to allow for the driving of additional

Jan 1, 1925