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By Bernardo Martins Braga

A prática de inertização de um distribuidor de 17,7 t para lingotamento contínuo de aços foi estudada numericamente através de um modelo matemático tridimensional não-isotérmico. O modelo considera uma única fase gasosa composta de dois componentes: argônio e ar. A turbulência foi levada em conta por meio do modelo k-e padrão. Os cálculos foram executados utilizando o software de CFD comercial ANSYS CFX. Diferentes configurações do sistema de inertização foram simuladas. Os resultados indicaram que a configuração atual é ineficiente e novas configurações foram sugeridas. Algumas recomendações para a correta prática de inertização também são fornecidas.

Jul 30, 2018

By AIME AIME

Adjustable Pyrometer-Stand. By L. W. BAHNEY, xxxvii, 33. Agency of Manganese in the Superficial Alteration and Secondary Enrichment of Gold-Deposits in the United States. By WILLIAM H. EMMONS, xlvi, 767. Application of Descriptive Geometry to Mining-Problems. By JOSEPH W. ROE, xxxix, 173. ARNOLD, C. EVERARD. The Giroux Shaft at Kimberly, Nev., xlii, 461. BAHNEY, L. W. An Adjustable Pyrometer-Stand, xxxvii, 33. BALL, SYDNEY H., and SHALER, MILLARD K. Mining-Conditions in the Belgian Congo, xxxix, 253. BEALS, ROGER L., and TWEEDY, GEORGE A. Cyanide-Plant and Practice at the Minas del Tajo, Rosario, Sinaloa, Mexico, xxxviii, 123.

Dec 1, 1910

By J. S. Jaspal

Mining of thin coal seams is both difficult and uneconomical. As a result, most of thin-seam coal reserves in the U. S. are not being mined. It is estimated that nearly 910 Gt (K. Unrug, 1985) of coal reserves exist in 355 to 710 mm thick seams. The Bureau is attempting to develop new techniques for mining 150 to 1065 mm thick coal seams. This paper summarizes the research work on existing thin-seam mining techniques, testing on small and full scale physical models of the Bureau slot mining concept, and computer modeling of the full-scale process.

Jan 1, 1992

By Catherine T. Aimone-Martin, Elena Oana Jacobs, Brent Meins

Accurate pressure measurements during underwater detonations are critical for the protection of structures and mitigating impacts to fish and marine mammals. Current guidelines that limit underwater pressures are based on past studies, many of which used sample rates of 48 and 65 kS/s (48,000 and 65,000 samples per second). These sample rates may be insufficient to accurately record high frequency, sharp rise time blast pressures. As such, pressure thresholds associated with fish and marine mammal injury or mortality may be underestimated, calling into question the pressure and sound pressure level guidelines that govern underwater blasting today.

Jan 1, 2019

By Fred B. Brost

In 1976, a decision was made to install a conveying system to transport ore 10.3 km (6.4 miles) from the new Eisenhower mine to Twin Buttes. The system, supplied and installed by Cable Belt Ltd., of England, represents a radical departure from conventional conveyor systems. The driving tension is applied through two endless wire ropes while the belt acts only as the carrying medium. Features of the system are a single 2240-kW (3000-hp) drive and a 60° angle bend. Construction was completed in two years and full production was attained alter several mouths operation.

Jan 12, 1979

By Alla D. Mah

Thermodynamic calculations for antimony and its compounds have been hampered by the lack of adequate basic thermal data; much work rains even to fill the more important gaps. This paper supplies heat and free energy of formation values at 298.15° K, for the sesquioxide and tetroxide, based upon new measurements conducted by the Bureau of Mines. The heats of formation were obtained by combustion (bomb) calorimetry, and the free energies of formation were obtained by combination of heat and entropy data. The new values are believed to substantially improve the accuracy of thermodynsunic considerations involving these oxides.

Jan 1, 1962

By C. E. Jordan, B. J. Scheiner

The Bureau of Mines has developed a continuous ultrasonic flotation cell for the recovery of Florida phosphate ore. Within a small mixing chamber near the bottom of the flotation cell, an ultrasonic probe agitates an injected mixture of air, water, and phosphate ore and breaks the air into fine bubbles. Phosphate particles are preferentially attached to these fine bubbles and floated in the main chamber of the flotation cell. Over 94 pct of the phosphate was recovered, resulting in a 30 pct P205 concentrate. The ultrasonic energy consumption was less than 7 kW.h/mt of phosphate ore.

Jan 1, 1989

By K Louie

When BHP Copper's Lower Kalamazoo Project commenced production in January 1997, two of the four original hoists had been converted to hoist ore from the Lower K level. Conversions on these hoists not only allowed hoisting from a much deeper level, but also created a higher hoisting efficiency and higher capacity as well. Conversions included new drums, new cables, SCR drives and other solid state control technologies not available when the original hoists were installed. Two of the original hoists were installed in the 1950's and the other two were installed in the 1970's.

Jan 1, 1998

By A. J. Monhemius, R. G. Reddy, G. W. Warren, E. Peters

Thermodynamic solubility of chromium in pickling solutions (i.e., HF- HN03-H2O solutions) was determined as a function of HF and HNO3 acid concentrations at 298K. Pure Cr, AISI type 316 and 416 stainless steel were used in this study. The results showed that the solubility of Cr increased with increase in the concentrations of HF and HNO3 acids in solutions. The solubility of Cr increased in the order of pure Cr > 416 SS > 316 SS. The theoretically calculated Cr solubility data were in reasonable agreement with the experimental data.

Jan 1, 1993

By V. Panchanathan

The rapidly solidified Nd-Fe-B powders form the entire basis of the bonded magnet industry At present the rapid solidification is carried out exclusively by melt spinning, producing flake like particles having highly stable and magnetically hard microstructure These particles are comminuted into powder before being processed into bonded magnets These powders are magnetically isotropic having coercivities from 4 to 16 kOe The other type of powder recently introduced for bonded magnets is the anisotropic powder made by the hydrogen decomposition desorption recombination (HDDR) process. The characteristics and application of these isotropic and anisotropic powders are discussed.

Jan 1, 1997

By K. O. Bennington

Enthalpies of formation of three sodium titanates were determined by hydrofluoric acid solution calorimetry, The values obtained for formation from the elements at 298.15° K are -370.9±0.5 kcal/mole for Na2TiO3, -832.1±0.9 kcal/mole for Na2Ti307, and -1,510.9±1.7 kcal/mole for Na2Ti6013. Tables of enthalpies of formation and Gibbs energies of formation are given as a function of temperature both from the elements and from the component oxides for Na2Ti03 and Na2Ti307.

Jan 1, 1973

New York Meets first Wednesday after first Tuesday of each month. W. FRANCIS, Chairman, WILLARD S. MORSE, Vice-Chairman. THOMAS T. READ, Secretary, Woolworth Bldg., New York, N. Y. P. A. MOSMAN, Treasurer. LOUIS D. HUNTOON. WILLIAM A. POMEROY. Boston Meets first Monday of each winter month. HENRY L. SMYTH, Chairman. ALFRED C. LANE, Vice-Chairman AUGUSTUS H. EUSTIS, Secretary-Treasurer, 131 State St., Boston, Mass. ROBERT H. RICHARDS, ALBERT SAUVEUR. Columbia FRANK A. ROSS Chairman. RUSH J. WHITE, Vice-Chairman. LYNDON K. ARMSTRONG, Secretary-Treasurer, P. O. Drawer 2154, Spokane, Wash. FREDERIC KEFFER, FRANCIS A.,THOMSON.

Jan 4, 1915

By Michael D. Sopko

This paper describes the project implementation from financing, through the engineering and construction phases, mine and process plant commissioning as well as operating experience realized to-date. The single line flowsheet used to process the lateritic nickel ore to a 75 percent nickel matte is presented with emphasis on the main pyrometallurgical operations. These include a rotary dryer, a unique reduction kiln, a 45 000 kVA electric furnace and two Pierce-Smith type converters. Associated infrastructure facilities and services necessary to sustain the 11 300 tonnes (12 500 short tons) per year nickel production rate are also described.

Jan 1, 1979

Some 30,000 people attended from 50 countries. Over 600 exhibitors brought with them a billion dollars of mining technology, ranging from tiny high-precision valves to giant off-highway trucks. Twenty-seven technical sessions with more than 100 papers covered the gamut of mining advancements. It was a grand display of industry vitality just to power the huge exhibit area required 22,000 kW of electricity each day, and support services for the exposition created more than 1000 daily jobs for local labor. Unquestionably, Las Vagas knew the miners were in town for the American Mining Congress' International Mlining Show.

Jan 11, 1978

Methane predrainage from coal seams in the Western Area of the U.K. has been practiced over the past decade. The differing reasons for the practice include the controlling of gas emission rates in coal headings required to win out coal faces and also the need to control the gas emission rates in the roadways of retreat faces in order to comply with the statutory requirements. There are some similarities with predrainage experience in the Bulli Seam NSW. The several case studies highlight the varying conditions in the Western Area coalfield where the use of predrainage was Required.

Jan 1, 1982

By J. Routh

Analysis of AI, As, Ba, Be, Ca, Cd, Co, Cu, Fe, K,. Mg, Mn, Mo, Na, Ni, Pb, Sb, Se, Sr, 11, V and Zn in various types of samples collected at Van Stone mine (a Pb-Zn deposit in Washington) and surrounding areas indicates that the concentrations of several elements in water, soil and sediment are higher than their background. values. Concentrations of metals in water decrease sharply downstream and are below the maximum contaminant levels specified for drinking water. Under present physico-chemical conditions, contamination of water is insignificant but the enrichment of heavy metals is found in soil and sediment.

Jan 1, 1994

By S. K. Kawatra

Outokumpu Electronics has designed a new on-line coal slurry ash analyzer, based on an instrument developed at Michigan Technological University. The primary goal was to build an accurate instrument at the lowest possible cost. The instrument determines ash content from measurements of X-ray backscatter, iron K, fluorescence, and low-energy y-ray absorption. It is capable of measuring the ash content with a standard error of 1.1% ash over an analysis range of 9-21% ash and 7-22% solids. The analyzer was tested on coals from United States, Poland, Great Britain and the USSR.

Jan 1, 1993

By Abdallah Khair, Nathalie Risso, Arie Herrera, Victor Tenorio

This study introduces a machine learning strategy to optimize icy regolith extraction from the Shackleton-de Gerlache Ridge using autonomous mining equipment. The model incorporates key parameters—distance, road gradient, vehicle load, speed, recharge logistics, and regolith water content—into a cost framework for excavation, hauling, and dumping. Regression models estimate energy and time requirements; classification predicts terrain navigability; clustering groups craters for efficiency; and K-Nearest Neighbors (KNN) determines optimal routing and scheduling. The system adapts to a six-month daylight cycle to maximize productivity and minimize costs, enabling intelligent planning for sustained lunar resource extraction under extreme environmental and logistical constraints.

Feb 22, 2026

One of the first all-hydraulic crawler drills in service at a US open-pit mine has significantly exceeded the penetration rates of comparable pneumatic crawler rigs, according to Atlas Copco Inc. Overall production with the hydraulic unit has been double that of pneumatic crawlers in use. The installation is at the Foote Mineral Co. surface mine at Kings Mountain, N.C., where the company is engaged in mining spodumene, a combination of lithium, aluminum, and silicates. The ore is found in pegmatite dikes, a tough and abrasive host rock with compressive strength of tip to 5800 kPa (40,000 psi).

Jan 9, 1978

T. S. FULLER, Chairman C. H. MATHEWSON, Past-chairman W. A. SCHEUCH, Vice-chairman J. L. CHRISTIE, Vice-chairman E. M. WISE, Secretary International Nickel Co., Bayonne, N. J. W. M. CORSE, Treasurer Executive Committee H. A. BEDWORTH W. M. PEIRCE D. K. CRAMPTON A. J. PHILLIPS E. H. Dix JR. GUY C. RIDDELL R. F. MEHL J. WALTER SCOTT JEROME STRAUSS Finance Committee C. H. MATHEWSON, Chairman W. M. CORSE H. S. RAWDON ZAY JEFFRIES SAM TOUR Data Sheet Committee R. S. ARCHER Chairman N. B. PILLING Vice-chairman L. W. KEMPF JEROME STRAUSS A. J. PHILLIPS F. L. WOLF'

Jan 1, 1932