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By Dietrich Gross

This paper describes an advanced oxy-fuel combustion technology for re-melting aluminum that significantly reduces energy consumption and emissions. This oxy-fuel combustion technology developed by Jupiter Oxygen is a patented process for combustion of fossil fuels with pure oxygen while excluding air, thereby creating an undiluted high flame temperature and increased efficiency for process heating in industrial furnaces. This unique process has led to improved heat transfer and longer residence time while maintaining the same process temperatures as with air combustion. The energy efficient combustion process allows aluminum companies to operate at a substantially lower cost due to a dramatic fuel savings of up to 70% for natural gas and waste oil (1). The results of more than 10 years of day-to-day experience utilizing the Jupiter Oxygen Corporation oxy-fuel combustion technology licensed to Jupiter Aluminum Corporation in the aluminum re-melting business are discussed.

Jan 1, 2008

By J. Kallioinen

Theoretical considerations, experimental results and plant experience have lead to a new design concept called the unit reactor approach. It has been successfully implemented to the largest flotation cell on the market, the 4000 cu ft OK TankCell. The work has also lead to a new operating idea called size specific flotation. The paper discusses these concepts in the view of full scale field experiments. In large scale porphyry copper flotation experiments conducted in Chile the new large TankCell with its new low energy input Free Flow mechanism out-performed the more conventional designs. The recovery was substantially better, especially in the coarse fractions. In some experiments the difference in total recovery was up to 10%-units and the savings in total energy consumption at the same time over 40%.

Jan 1, 1995

By C. Langer

Although the existence of precious metals, particularly those of the platinum group, in the nickel ores in the Sudbury district has been known for a good many years- almost as long as the ore deposits themselves- the Mond Nickel Company were the first to effect their recovery on a commercial scale. The precious metals values of the different Sudbury ores vary considerably, and are generally higher in the copper-rich ores. These values are so very small that a direct determination in the ores gives quite unreliable results. This is not surprising if one considers that some of the ores contain on1y one unit of total precious metals in about two million units of ore, and that this one unit will consist of seven different metals, each with a different chemical behaviour. It is only after the ores have been smelted to a Bessemer matte containing about 80 per cent combined copper and nickel that the precious metals content can be determined with some degree of certainty. From the figures thus obtained, the precious metals content of the ores can be calculated, provided the tonnage of ore used to produce one ton of matte is known. The recovery of these minute quantities of precious metals out of ?such a large amount of gangue and sulphides of iron, copper, and nickel seems at first glance a commercial and technical impossibility. Nevertheless, science has found a way to conquer all the difficulties, and quite substantial quantities of the precious metals contained in the Sudbury nickel-copper ores have been regu1arly recovered for many years by the Mond Nickel Company.

Jan 1, 1927

By Barnettm Ray R.

As a result of the Farmington explosion, the U. S. Bureau of Mines commissioned the National Academy of Engineering to a determine what steps could be taken in a short time frame to significantly reduce fatalities as a result of underground fire and explosion in coal mines. Three areas were named by the Academy as having the greatest potential; survival, communications, and rescue. The Bureau subsequently awarded a $3-5 million contract to the Special Systems Division of Westinghouse Electric Corporation for the development of prototype equipment and procedures. These were recently tested in a simulated emergency situation and will be delivered soon. Contractor recommendations for utilization and for further development effort will be studied and appropriate action taken.

Jan 1, 1971

By John P. Mahaffey

Thank you Mr. Chairman, Ladies and Gentlemen of SME-AIM? for this opportunity to talk to you about, one of the most interesting and challenging facets of our mining industry. Because the need was then -we built in 1964 what is still today, one of the most sophisticated AC mining machine simulators for this or any industry. It simulated the electrical controls and circuits of an AC shuttle car. The student activated the controls on the main console, which represented the elementary control and power circuits. Its accompanying slide-tape program, student manual and worksheets provided our customers with an effective and highly motivational means to teach their face mechanics: 1. practical AC circuit and motor theory 2. print reading 3. troubleshooting techniques Nearly 10,000 men have put in over 100,000 manhours of training on the AC panel and its DC counterpart. The DC panel was modeled after the 14BU10 Loader. The success of these larger panels pointed out the need in our industry for an orangized, basic electrical program designed around mining machinery components & circuits. But probably more importantly, they brought to light the tremendous thirst for upgrading by our industry's employees. We then turned our attention to developing programs around very basic panels. The resulting programs were designed also to assure maximum student involvement.

Jan 1, 1975

By F. D. DeVaney

The supply of manganese is a subject of much interest. The idea of obtaining it from rhodochrosite-MnC03 is attractive because the carbonate is supposed not to be so contaminated with impurities as the commonly utilized oxides. Large bodies of rhodochrosite-bearing rock have been known for a long while to exist at Butte, Mont. Hence samples were obtained from that place. In the two samples examined quartz was the chief diluting substance. The leaner sample was about one half quartz; some copper, lead, zinc, and iron sulphides were also present. The rhodochrosite amounted to about 40 per cent, so that the sample had a tenor of about 20 per cent manganese. This sample was the subject of the examination reported herein.

Jan 1, 1928

By Honggang Zhong, Wei Du, Qijie Zhai, Junjie Sun, Jingzheng Ye

"Effects of pouring temperature and cooling water flux on solidification structure of ferritic stainless steel are investigated with a thermal simulation setup. The results show that with pouring temperatures 1518° C, 1528° C, 1538° C and 1548° C, both Lmean (the mean length between columnar to equiaxed transition(CET) position and chill surface of the samples) and the mean dimension of equiaxed grains increase. On the other hand, with cooling water flux 400, 800, 1200 and 1600mL/min, Lmean gradually increases, and the mean dimension of equiaxed grains decreases. In addition, low pouring temperature and cooling water flux enlarge the ratio of fine equiaxed grains.IntroductionFerritic stainless steel plays an important role in industry products nowadays. Compared with austenitic stainless steel which contains both chromium and nickel, ferritic stainless steel can obtain good corrosion resistance despite the absence of nickel [ 1]. F erritic stainless steel has been widely applied in automotive exhaust systems [2], electrical equipment, construction and chemical industries and also has broad development prospects. At present, continuous casting technique has developed into an important technology applied in iron and steel making. The solidification structure of continuous casting slab has significant influence on the final properties of stainless steel. The developed columnar grains of ferritic stainless steel would result in negative effects on mechanical property [3]. However, fine and homogeneou& equiaxed grains can improve the comprehensive properties of ferritic stainless steel [4] Therefore, it makes great sense to promote the columnar to equiaxed grain transition (CET). Recently Baosteel has developed a new type of Cr-saved ferritic stainless steel, but the effect of continuous casting conditions on its solidification structure is unknown. It is important to investigate the effects of solidification conditions on solidification structure of this new ferritic stainless steel, which can give guidance for optimizing the production process."

Jan 1, 2014

By J. R. Ruark

This report presents results of the research and development work and operations performed during stage II of the gas combustion retorting research program conducted by the Colorado School of Mines Research Foundation and six major oil companies at the Bureau of Mines Anvil Points Research Facilities. The experimental program, including retort modification and air-gas distributor development, effects of shale quality and particle-size distribution, and other variables on the process, is discussed. Although operating problems are not fully resolved, it appears that the gas combustion retorting process can be successfully applied to achieve oil yields in excess of 85 percent of Fischer assay at mass shale feed rates of 500 pounds per hour per square foot of cross-sectional bed area, approximately twice the rate previously demonstrated to be reasonably practicable.

Jan 1, 1971

By David J. Forrester

"CANMET’s research into underground coal mining is primarily conducted at the Cape Breton Coal Research Laboratory (CBCRL), established in 1981 to conduct safety research in underground coal mines. Located close to Canada’s largest underground coal producer, in the Sydney Coalfield of Nova Scotia, CBCRL’s program also includes the two western underground coal operations. CBCRL is a relatively small laboratory with a staff of thirteen — eight professionals and five support staff — with an annual budget of over $1 million. In order to maintain effective research response, flexibility is key and staff are increasingly working in project teams, crossing traditional section ties and also drawing from specialist expertise elsewhere within CANMET.CBCRL’s research activities have had a substantial impact on the Canadian underground coal mining industry, particularly in Cape Breton. CBCRL contributed to Cape Breton Development Corporation’s (CBDC’s) threefold reduction in lost-time accidents in the 1980s. Also, in the last four years alone, CBCRL’s work has enabled CBDC to save over $17 million in improved utilisation of reserves and cost savings. The work embraces the three traditional areas of mine environment, strata mechanics and mining technologies, however the current direction has been strongly influenced by recent external and internal factors. It is timely to review progress and recent directions."

Jan 1, 1996

By Herbert Pöllmann

Waste disposals are needed for safe deposition of different kinds of materials which can not be used as secondary raw materials. Often high contents of heavy metals must be bonded tightly to cristalline compounds to protect the environment from contamination. Therefore it is important. to find minerals which are capable to incorporate different heavy metals and protect the ground water. The power of resistance against leaching out effects of highly water-soluble salts can be increased. Mineral groups of metal hydroxy salts, ettringites, apatites, sodalites and calciumchlorosilicates and their hydrates are recommended for their formation in mineral reservoirs. Different wastes as red mud, gasification ash, garbage combustion ash and fluidized bed ashes were included in this study. The formation of different new compounds and their properties were determined.

Jan 1, 1991

By Juan Manuel Ojeda Sarmiento

Los clusters como concentraciones geográficas de compañías interconectadas e instituciones dentro de una actividad particular. La interacción de estas organizaciones generan un clima de negocios que estimula la mejora en su desempeño, competitividad y rentabilidad de largo plazo. En ese sentido, el presente texto describe el cluster alpaquero como propuesta de desarrollo comunitario local para la provincia de Candarave - Tacna, que integra la producción primaria de fibra de alpaca, transformación en sombreros, peletería y textiles, y su comercialización en mercados regionales, nacionales y externos.

Sep 14, 2009

By E. A. Cleveland

A glance at the map discloses the fact that the Pacific Great Eastern railway either traverses or crosses some of the most important rivers of the province: the Squamish with its branches the Stawamus, Mamquam and Cheakamus; and the Green, Lillooet, Birkenhead, Fraser and Quesnel rivers. Each of these and some of their tributary streams, having their ?sources and upper reaches in the higher altitudes in regions of abundant snowfall, is capable in greater or less degree of furnishing water under suitable heads for the economic production of power. Beginning at its present terminus at Squamish the railway has the only hydro-electric development within its territory among the whole list of streams mentioned. A 225 horsepower installation at the edge of the East branch of the Squamish river, using water from Stawamus river, a branch of the former, under a head of 418 feet, is a modest beginning. Two or three additional sites, where water may be used under somewhat similar heads, may be found on this little stream. Next above Squamish, along the route of the railway, is the Mamquam, a long tributary of the Squamish from the eastern slopes. It has a drainage area of something like 130 square miles with widely varying discharges of from less than 50 to about 14,000 cubic feet per second. The preliminary investigations so far have disclosed no suitable storage sites, so the Mamquam may be regarded as a small continuous power stream - probably less than 1000 horsepower.

Jan 1, 1925

By E. J. Gleim

[of- ac tore affecting the e -success of recent conveyor miningsystems forLt. extraction. 1 GL C ,_tfreedom shoot &apos;_)`u 2--ethe.1 is coal while e en othershot firers re:7 t _e&apos; _U-tin , w J, e coal .Z- 311.ing States conveyors because ;-.;lax .ca requires thatblasting be limited to when c .. men os. _o tend neces¬sary officials 1 s . re out c-z ,r 7t ...y e:e l z<: woes no t a -¬#to 1 C" such restriction on blasting conveyor miningbeen extendedWhere ere t ere. re no _ c: t&apos;_ _c tit-----! . kind cutlasting;,1CL?; C&apos;. _ z)carried anI-7LC. AT continuouslyHowever, unless et._&apos;0:, precations are taken under r&apos;t e , accidents, n is or such, as111 electricity r 1C- from.J--_,._.1t ,° =&apos;1?without usingholes, as well as numerous-o _&apos;1&apos;-1 -= e troublehe record of mineexplosions (some of themSo so _C&apos;_ °:&apos;,v 0f rock- dusting]

Jan 1, 1941

Jan 1, 1925

By J. A. Bartnik

Flocculation, the process of coagulation or coalescence of finely divided particles, is commonly used in separating fine solids from fluids. Forces disposing of the particles to flocculate include: ionic forces of attraction, secondary entropic forces, and magnetism. Magnetic flocculation is due to a physical magnetizing process which affects suspended ferromagnetic particles. Such particles, after exposure to magnetic fields strong enough to cause reorientation of the particles and alignment of the induced magnetic poles, tend strongly to retain this induced magnetism, as the magnetic retentivity of ferromagnetic particles is a linear function of its specific surface.1 Thus, because they become small magnets with high residual magnetism, the particles become and remain attracted to one another, forming large agglomerates. Fine magnetic particles close to domain size can exhibit energies of the magnetization of the order of 105 ergs/cm3,2 which is many times greater than the energy affected by chemical flocculents. Therefore magnetic flocculation can be used to agglomerate particles having surfaces ionized with like charges and only a minute quantity of ferromagnetic material will be necessary to develop sufficient force to overcome the repulsive ionic forces and hold together relatively large masses of fine solid agglomerates suspended in fluids. Since flocculation occurs after the fine suspension passes through a magnetic field generated by magnets surrounding a pipe section, the simplicity of the process and economic advantage makes magnetic flocculation very attractive.

Jan 1, 1971

Nearly as impressive as the machines that will be on display at MINExpo are the massive engines and tires that keep the machines moving. As you can imagine, it takes a special tire and special engine to run these machines. The following is a look at some of the exhibitors that will be at MINExpo displaying engines and tires. Cummins Inc. Cummins Inc. will display a lineup engines from 37kW to 2,983 kW (49 hp to 4000 hp) at MINExpo, representing the most extensive ?smallest to largest? range the company has ever put on display.

Jan 1, 2012

By A. J. Basu

Rock mass properties testing for determining strength parameters is an integral part of geomechanics. These tests are performed either in a laboratory environment or in a field (in-situ). The authors share their experience in using numerical modelling in simulating the laboratory test procedures. This approach helps studying the rock breakage and failure mechanism more efficiently and provides a high degree of visualization. Moreover, imperfections and discontinuities can be easily incorporated in these models. This capability of providing arbitrary fractures and discontinuities facilitates in building a large knowledgebase of rock strength and failure mechanisms. This knowledgebase may then be used to generate heuristics for determining rock strengths for rock mass with fractures and discontinuities.

Jan 1, 1997

By S. B. Castor

Proceeds from industrial mineral mining in Nevada were approximately equal to those from metal mining during the barite boom in the late 1970s and early 1980s; however, since then the economic importance of industrial minerals has been overshadowed by gold mining (Fig. 1). The total value of industrial minerals mined in Nevada increased by about 60% during the 1980s, reaching an estimated $306 million in 1990 before falling slightly in 1991. The state&apos;s most important industrial mineral commodities, in order of estimated value, are aggregate, lithium carbonate, diatomite, lime, cement, gypsum, barite, clay, silica, and magnesia (Fig. 2). Industrial minerals produced on a smaller scale are colemanite, dimension stone, dolomite, perlite, salt, and zeolite. In 1991 industrial mineral commodities other than aggregate were produced at 39 operations in Nevada. Most of these operations are located near the two major metropolitan areas of the state, or along the major transportation routes (Fig. 3).

Jan 1, 1993

By M Russ, J Gediga

This paper shows an economic feasible approach to implement greenhouse gas (GHG) reduction measures into the mining and metallurgy industry (MMI). The goal to improve energy consumption is directly linked to the reduction of GHG emissions in the MMI. A baseline scenario of the considered reference system and of the respective reference year has to be designed and analysed. In a second step an analysis of the same operation using the best available technology (BAT) processes is carried out to generate a basis for a benchmark system. The identified gaps will be reported and the potential GHG emission reductions will be put into relation to the investment, running cost and generated carbon credits of the new process technologies to be implemented. This economic feasibility calculation is necessary to realise a cost efficient GHG reduction roadmap decision-making for implementing new technology into the companyÆs business operations. The GHG reduction roadmap is developed using the marginal abatement curve approach.

Jan 1, 2009

By K. C. Ko

The pit slope angle dictates the economics as much as the depth of the pit. Steeper slope provides more ore reserves, at the same time, the steeper slope presents higher probability of instability and associated maintenance problems. While large open pit mines mostly belonged to nonferrous metals in the past, other mines are becoming deeper as the mine economics permits deeper mine operations, Such minerals include coal, uranium, phosphate, and others. There are some basic differences between an open pit slope and slopes that are encountered in usual civil engineering work such as dam embankments and highway cuts (Figure 1). The stability of the civil engineering slope changes continuously with time due to ground-water movements, weathering, etc. But the stability of the open pit slope (Figure 2) changes more drastically day-to-day or even hour-to-hour, These changes occur because not only is the slope geometry being continuously changed by the mining operation, but also different geology and geologic structures are being exposed on the slope. Even when a particular slope area is not presently being mined, excavation in adjacent areas can affect the general condition of that slope area. A pit will experience some slope failures during its life.

Jan 1, 1977