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By Charles Rich, Robert Munson, Leonard Obert

Improved methods of predicting the caving characteristics of ore bodies is discussed. Experiments were conducted at Climax mine, Climax, Colo., on varied rock compositions. The cavability of adjacent areas, as well as seismic energy absorption proved to be good factors in determining cavability. Seismic velocity, core recovery, and rock quality designation (RQD) were found to be not as reliable.

Jan 1, 1977

(Under this heading will be published notes sent to the Secretary of the Institute by members or other persons introduced by members.) Experienced mining engineer, Columbia School of Mines graduate, practical experience in drifting, shaft sinking and development work, also in mining, operating and equipping iron, copper and zinc properties. Married, age 32, available at once. Open for position as superintendent or assistant. No. 462. Member, mining engineer, age 39, married, technical graduate, 12 years' experience in gold mining and milling; past four years as superintendent of large properties. At present employed but open for engagement after July 1; will consider no position not offering a future. Salary $4800. No. 467. Member, mining engineer, age 46, married, desires a position as superintendent, or an opening with an industrial company of permanency. Western and Alaskan experience in mining, cyanidation anti concentration. At present manager of an Eastern property, but desires a change. Available on thirty days' notice. No. 468.

Jan 7, 1918

By B. W. Wallace

Permitted explosives in South Africa are those explosives approved by the relevant State authority for use in fiery coal mines. The main tests that an explosive must pass for this approval are the gallery tests derived from the Buxton (U.K.) classification. These tests are described briefly. In addition, the safety of permitted explosives is affected by their ability to deflagrate, and to produce a naked flame after blasting, rather than to detonate fully. Tests done on this phenomenon are discussed. A further potential hazard of explosives is after-blast fume. The testing and behaviour of several permitted explosives in this respect are covered, both in the laboratory and in the field. Performance testing of permitted explosives, specifically the double-pipe, underwater, and ballistic mortar tests, and their relationship to field use, are considered in some detail. The application of traditional and new tests to permitted explosives leads to guidelines for the safe and efficient formulation and use of these products.

Jan 1, 1986

Comalco Aluminium Limited uses a computer system for cost, supply and maintenance reporting and control at its bauxite mine in Weipa, North Queensland. The system collects data on a daily basis at a high level of detail on both cost and maintenance history. This allows useful reporting to all levels of management from the shop floor to the General Manager. The most successful aspect of the system is that the information is available in all workshops on visual display units. This allows the real spenders of the Company's money, Foremen and Tradesmen, to make well informed decisions. The system has also decreased the time taken to find parts and information which gives the Foremana greater opportunity to do his real job of supervision and quality control.

Jan 1, 1983

By Andrzej M. Wala

The determination of the air quality needs to dilute diesel exhaust gases to a safe level must be individually evaluated for particular cases. One such case is when diesel-powered vehicles are working in long dead- end headings with forcing auxiliary ventilation. The vehicles perform specific operations in a cyclic order required by the technical process. The dynamics of this process in certain conditions has a vital influence on environmental conditions in the working area and in the rest of the heading. Recent studies on diesel gas behavior in long headings have shown a zone of increased concentration of pollutants (accumulation) between the face and the mouth of the heading. To be able to control these accumulations of pollutants, use of the concept of planned air discharge by using the Coanda-type ducts is proposed. The main objective of this paper is to demonstrate an application of computer simulation of that process. It is shown that, by planning the additional air discharge, the concentration of diesel gases can meet required limits along the heading.

Jan 1, 1987

By M. Galetakis, C. Roumpos

A sustainable coal industry needs to achieve a number objectives concerning mainly with superior utilisation of deposits and improved environmental performance. Modern quality control systems, which are greatly based on the on-line analysers, play an important role in achieving sustainability targets. This paper discusses the testing and application of on-line ash analysers installed in the Ptolemais and Megalopolis lignite mines in Greece and examines the possibility of using this type of analyser to control blending and homogenisation operations. The effect of the accuracy of on-line analyser to control process, when used for the characterization of low rank coals with complex and variable composition, such as greek lignites, is examined.

Jan 1, 2005

By P. Barnes

Several interesting and important considerations may be based upon an analysis of the cost of producing Bessemer rails, and the facts thus set forth may be much more clearly emphasized by re ducing each item of cost to its own fractional proportion of the sum total in each branch of the manufacture. The estimate given below is not absolutely complete in minute ness of detail, but it may be fairly taken as a basis for the suggestions to be noted : Perhaps the most striking comments that can be made upon this statement are those arising from a consideration of some of the smaller items, and even the least of these quite loses its insignificance when its proportion of the whole is expressed in actual money, as for the work of a year, or even for a single day. Thus, if the item as be considered, the importance can be clearly

By Miguel Olivas-Martínez

A two-dimensional computational model for the hot filament chemical vapor deposition (HFCVD) process to produce diamond films is presented. The model incorporates the transport of momentum, energy, and mass inside the reaction chamber of a HFCVD reactor. The gas-phase homogeneous reactions were represented by a simplified reaction mechanism. The gas-phase transport equations were coupled to the kinetic expressions representing the catalytic dissociation of the molecular hydrogen at the filament surface and the deposition rate of the diamond film on the substrate. The computational model was solved numerically by means of a commercial software. The model predictions showed good agreement with the experimental data reported in the literature in terms of both temperature and methyl concentration profiles along the filament-substrate center distance. Examples of the potential applications of the present formulation for the design and further optimization of the HFCVD reactor are discussed.

Jan 1, 2006

By Antonio Peralta, Guillermo Dante Ramírez-Rodríguez

Mining is generally considered a large-scale hightech industry. However, it has estimated that about 12 million people, about 30% of the world’s total mining workforce, relied on small-scale mining for their livelihoods. During the years, the large-scale mining industry has developed best practice environmental procedures, which have been applied in diverse settings through the world. In contrast, small-scale mining is better known for its high environmental impact and the lack of safe and healthy working conditions. This paper will discuss the environmental control strategies used by the large-scale mining industry, and its applicability to small-scale mining in developing countries.

Jan 1, 2005

(Members are urged 'to, send in for this column any notes of interest concerning themselves or, their fellow-members.) Members and guests who registered at Institute headquarters during the period Sept. 10 to Oct. 10, 1915: George H. Blakemore, Sydney, N. S. W. W. B. A. Dingwall, San Antonio, Tex.. H. Haege, Sydney, N. S. W. R. H. Jeffrey, London, England. C. A. Filteau, New York, N. Y. H. S. Emlaw, Spring Lake, Mich. Myron R. Walker, Cerro de Pasco, Peru. Y. T. Woo,' Tientsin, China. William R. Grunow, Morenci, Ariz. A. L. DeDeken, LouVain, Belgium. E. DeGolyer, Norman, Okla. K. P. Swensen, Tokyo, Japan. William W. Elmer, Tuttletown, Cal. Charles Enzian, Wilkes-Barre, Pa. Huntington Adams, Iquique, Chile. C. F. Schnepp, Cobalt, Ont., Canada. W. Ray Cox, for several years Mineral Inspector of the General Land Office at Portland, Ore., has been appointed Professor of Mining and Metallurgy in the School of Mines, Oregon Agricultural College, Corvallis, Ore.

Jan 11, 1915

By R. H. T. Garnett

Offshore mining of placer diamond deposits along the coast of South Africa and Namibia has become a multi-scale activity. It is a successful offshoot of a land-based mining industry that has operated along the coastline for more than 80 years. Onshore diamond deposits have been worked by several methods from the foreshore to some kilometers inland (Hodgen). These deposits are the foundation of an ongoing industry along the coastline. The offshore diamond industry began in the late 1950s and has now come of age. Diamonds are produced along 800 km (500 miles) of coastline in water 200 m (660 ft) deep. About half of the coastline is in Namibia, north of the Orange River that defines the border with South Africa. The other half is in South Africa.

Jan 1, 1995

Several surface coal mining operations in North America are attempting to adapt microprocessor-based monitoring equipment as well as programmable logic controllers onto rotary blasthole drills, towards improving overall drill and blast productivity. These Monitoring While Drilling (MUD) systems permit the recording and processing of important drilling parameters such as rotary speed and torque, instantaneous penetration rate and weight on the bit, and enable the operator ultimately to optimize drill and bit performance. MWD systems on production drills in surface coal mines offer the potential to define mine bench geology in detail and in advance of explosives loading. Recent advance s in explosives and initiation technology will require such a detailed knowledge of ground conditions in order to be fully exploited. Additionally, the logic developed from drill monitoring technology will eventually enable full drill automation through feedback and control, once a more complete understanding of the influences of rock mass characteristics on machine performance is achieved.

Jan 1, 1988

By F. Bourgeois, J. A. Herbst, R. P. King

The ultrafast load cell (UFLC) has proved to be an exceptionally good device for the study of the fundamental processes associated with the impact fracture of particulate material. A new high- sensitivity UFLC has been commissioned at the Utah Comminution Center for the study of low-impact energy single-particle fracture. The force-time histories of individual fracture events have been measured. The force and energy absorbed at crack initiation have been measured at several particle sizes. The mass specific energy for fracture and the associated breakage function have been determined. The distributions of particle breakage energy and particle strength have been measured as a function of particle size.

Jan 1, 1992

COUNCIL OF NATIONAL DEFENSE W: S. GIFFORD, Director, GROSVENOR B. CLARKSON, Secretary. The Council of National Defense The Advisory Commission NEWTON D. BAKER, DANIEL WILLARD, Chairman, Secretary of War, Chairman.. (Transportation). JOSEPHUS DANIELS, BERNARD M. BARUCH, Secretary of the Navy. ' (Raw Materials). DAVID F. HUSTON, HOWARD E. COFFIN, Secretary of Agriculture. (Munitions, Manufacturing). FRANKLIN K. LANE, HOLLIS GODFREY, Secretary of the Interior. (Science and Research, including En¬ WILLIAM C. REDFIELD, gineerlng and Education). Secretary of Commerce, SAMUEL M. GOMPERS, WILLIAM B. WILSON, (Labor). Secretary of Labor. F. H. MARTIN, (Medicine and Sanitation). ' JULIUS ROSENWALD, (Supplies). At the request of Dr. Hollis Godfrey, Chairman of the Advisory Committee On Science and Research, which includes Engineering and Education, a Sub-Committee of Engineering Societies has been appointed with representatives as follows:

Jan 6, 1917

New York Meets first Wednesday after first Tuesday of each month. . DAVID H. BROWNE, Chairman. JOHN H. JANEWAY, Vice-Chairman. . F. E. PIERCE, Secretary, 35 Nassau St., New York, N. Y. P. A. MOSMAN, Treasurer. LEWIS W. FRANCIS. BENJAMIN B. LAWRENCE. Boston Meets first Monday of each winter month. HENRY L. SMYTH, Chairman. ALFRED C. LANE, Vice-Chairman. HENRY A. WENTWORTH, Secretary-Treasurer, 60 India St., Boston, Mass. A. H. EUSTIS, F. G. STANTIAL. Columbia Holds four sessions during year. Annual meeting in September or October. STANLY A. EASTON, Chairman. FREDERIC KEFFER, Vice-Chairman. LYNDON K. ARMSTRONG, Secretary-Treasurer, P. O. Drawer 2154, Spokane, Wash.

Jan 2, 1916

By Kathleen M. Kowalski-Trakofler

This paper discusses human judgment and decision making under stress. The authors review selected recent literature across various disciplines and suggest a definition of stress within the context of decision making during the management of emergencies. They also discuss fieldwork by the Pittsburgh Research Laboratory, NIOSH, which explores traumatic incident stress, the relationship between previous training and performance under stressful conditions, and human behaviour in underground mine fires. The authors assert that stress is one of the factors that decision makers must contend with in most life-or-death situations. They suggest that a better understanding of individual judgment and decision making activities whilst under stress would yield a better understanding of how people reach the choices they make in emergencies. This enhanced understanding would be of enormous value to emergency managers, researchers and policymakers.

Jan 1, 2003

Recent research publications in extractive metallurgy were analysed for their stated and self-evident objectives. Over 100 different objectives (not specific to a metal or unit operation) were identified. These were divided into groups of economic, environmental, professional and fundamental significance. Comparisons were made of the objectives adopted in universities, industry and national research organisations. The most common primary and secondary objectives (by a large margin) were "to develop a new process (different chemistry)" and "to determine the effects of variables on a process" respectively. It was concluded that, overall, recent research has been dominated by commercial objectives. Objectives related to thermodynamics and kinetics have been the most common of the fundamental sort. Those related to professional methods in general, sensors and process dynamics, among others, have been largely neglected.

Jan 1, 1986

By María Cristina Krause

"Dado que las empresas mineras tiene que respetar no solo las leyes particulares de cada país, sino también las exigencias internacionales planteadas por los inversionistas a través de estándares de entidades financieras,entre las que se encuentra el Banco Mundial, se plantea la obligatoriedad de implementar la participación ciudadana o consulta pública. En ese sentido, el objetivo del presente trabajo radica en mostrar el proceso de consulta pública o participación ciudadana no sólo como parte de un Estudio de Impacto Ambiental, sino como un proceso cuya eficacia permite utilizarlo durante toda la vida de la mina: etapas de exploración, de explotación, de cierre y abandono. De forma que este método posibilita conocer la percepción que las comunidades tienen del entorno minero y de un proyecto particular con la finalidad de advertir la opinión de los pobladores sobre las actividades mineras, enfrentar conflictos y monitorear los puntos de impactos socio-económicos, etc. "

Jul 31, 2003

By Boyd R. Davis

Like many pyrometallurgy researchers, Ralph Harris? work extended over both light metals (lithium and magnesium) and base metals. His work looked at feed preparation, primary production, and secondary treatment. The thermodynamic principles of chemical metallurgy allowed Ralph to move between these two groups of metals. However, these metals have few similarities when projects are being developed. The traditional ?deposit-based? drivers for base metal operations do not apply to the same degree with light metals projects. While high purity, low cost feed is important to light metals projects, it should not be considered as the main reason for a smelter project. While it is clearly understood that technology (energy costs) is the driver for aluminum production, it is less considered for other light metals. This paper will look at the break down of base and light metals? production costs to try to quantify the balance between feed costs and technology for each metal group.

Jan 1, 2013

Chlorination of organic matter by direct injection of chlorine gas or hypochlorite has been investigated metallurgically worldwide with little understanding of the basic chemistry of the passivation mechanisms in- volved. In this paper, chlorination of carbon is attributed to oxidation-reduc- tions, resulting in surface halogenation of graphitic or amorphous carbon. It is proposed that chlorine and carbon interact to form thin coatings of chioro-carbon complexes that block the adsorption of gold cyanide com- plexes, thus passivating the gold adsorption sites of carbonaceous matter. Analytical, spectrographic, microscopic and electron-optical methods have been applied to demonstrate the proposed mechanism of chlorine-carbon bonding, as well as to evaluate the advantages and limitations of chlorination in the pretreatment of refractory carbonaceous gold ores.

Jan 1, 1991