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By S. B. Bhagwat

Before the Clean Air Act Amendments of 1990, coal policies-especially coal research policies-were geared to find a solution to the sulfur emission problem. However, technologies to reduce sulfur emissions cannot be tailored for a single coal. A technology that will clean Illinois coal to compliance levels will do the same, or nearly the same, for most other types of coal. This paper will discuss an integrated approach to the analysis of the future of coals from different regions in the United States and its implications for coal-related policies by government and industry.

Jan 1, 1994

By D. G. Mirakovski, B. Krstev

The paper presents models of auxiliary ventilation systems with leaky ducts and algorithms for calculations of pressure loss, air leakage, and volume flow ratio and pressure fans. Two basic models are discussed: 1st model for a duct with leakage through the flange joints; 2nd model for a duct with an equivalent longitudinal aperture. The present analytical system has been successfully applied to developing of computer software named DAVentS. A. sample problem is used to illustrate efficiency and accuracy of DAVents software in solving most common problems in process of designing AVS.

Jan 1, 2002

By W. C. J. van Rensburg

Exploration of unconventional mineral resources is stimulated by uncertainties about the cost and security of conventional resource sup- plies. Costs of the latter are likely to increase as a result of inflation, higher energy costs declining productivity, a lack of sufficient investment in politically volatile areas, or through cartel-like action. Exploration of unconventional resources is likely to be delayed by these same factors, insufficient research and development facilities, and a decline in capital formation. World economic growth is likely to be slow, so there will be more emphasis on material conservation. Therefore, the incentive to explore for unconventional resources may be reduced.

Jan 1, 1983

By N. T. Rempe

The underground voids that result from mining provide opportunities for deep geologic waste disposal (DGWD). Such disposal could solve many environmental problems. DGWD takes careful planning, technology transfer and true partnership between waste generators and mine/repository operators. The US government is now planning on using specially mined excavations to dispose of radiotoxic and mixed waste. Using the experience gained from the domestic projects that are now in preparation and from foreign repositories that are now in operation, US mines can claim their rightful share of the growing market for DGWD.

Jan 1, 1998

By V. Bhagavathy

This paper describes a method for the determination of traces of rare earths using energy dispersive x-ray fluorescence spectrometry (EDXRF) after preconcentration of their oxine complexes onto activated carbon. Various parameters that influence adsorptive preconcentration of rare earths onto activated carbon viz. pH, amounts of activated carbon and oxine, time of stirring and aqueous phase volume were systematically studied. A numerical method based on simple least square procedure using fifth order polynomial with 25 consecutive values was developed for smoothing and differentiation of EDXRF data which was previously digitized and averaged. First order derivative EDXRF in conjunction with adsorptive preconcentration on activated carbon enables to determine as low as 10 ppb of each of individual rare earth elements.

Jan 1, 1989

By Jack Eloranta

Transmission of sound through the atmosphere is affected by local conditions. Anecdotal accounts of the sound of cannon fire traveling great distances go back to the Civil War. The Royal Society published a paper near the turn of the century concerning the reports from the cannons fired in London at the funeral of Queen Victoria. Early computers were used by the U.S. Army at Aberdeen in Maryland in the 1950’s to model airblast problems during munitions demolition. Today’s blaster has to have access to weather information beyond a simple local forecast. Surface winds, winds aloft and temperature profiles have a dominant role in neighbors reaction to blasting. Many ground vibration complaints are really airblast complaints. Blasters who maintain ground velocities under . 1 inches/ second are often perplexed by complaints from distant neighbors, even when local monitoring shows airblast to be under 110 dB. This paper will help the blaster identify warning signs of high airblast conditions.

Jan 1, 2000

By E. N. Pugh, J. V. Craig

WhILE it has been established that well-defined microhardness impressions can be produced in germanium by room-temperature indentation,1-3 the role of dislocations in the process is the subject of continuing discussion.4-7 Recently, Carroll and ~anaka'

Jan 1, 1969

By A. A. Berk

LAGGING technology and the slow spread of in- formation have been the chief obstacles to wide- spread participation in minimizing the industrial pollution load. These obstacles can be conquered by fact finding and applied research. There are three aspects to the problem of waterborne mineral waste: to minimize the amount being thrown away, to select a predisposal treatment, and to use the products or dispose of them.

Jan 7, 1957

By J. F. Kemp

The death, on the 30th of May, 1896, at Paris, of the venerable Gabriel Auguste Daubrée, an honorary member of the Institute, recalls with emphasis the great value of his varied contributions to geology, mineralogy and hydrology. In fact, more and more as the years pass, and as attention is given to the obscure problems of metamorphism, of the development of joints, of slaty cleavage, of schistosity, of fault-systems, of the subterranean circulations of water, and of many other agencies which are often closely involved in the production of ore-bodies, the appreciation of his work increases, and quotations from his papers are made. Daubrde was born June 25, 1814, at Metz. After receiving

Jan 1, 1897

By G. V. Basham

"Environmental audit" is a phrase that can raise the blood pressure of otherwise cool and calm corporate personnel. There is widespread concern that any organized effort to find environmental problems will do so and may result in the imposition of substantial liability against the business that engages in such activities. However, such audits can reduce rather than enhance possible liability. Relevant issues include: the role of the attorney in the process, liability risks associated with environmental audits, steps to maximize confidentiality of audit results, reporting requirements and use of audit results in a proactive manner.

Jan 1, 1995

By A. Stumpf, Y. Berube

An experimental apparatus for studying the aqueous oxidation of sulfide minerals is presented. The oxidation kinetics for molybdenite in solutions of caustic soda and dissolved oxygen are discussed; results of leaching experiments on chalcopyrite concentrates are given. Preliminary results on the transfer of oxygen into water are also discussed.

Jan 1, 1974

By Heinrich 0. Hofman

A T THE meeting of the Board of Directors on June 24, Prof. Heinrich O. Hofman was elected an honorary member of the American Institute of Mining and Metallurgical Engineers. Professor Hofman is best known to the world at large for his publications, and in this respect he is to this generation what Schnabel was to the previous one. The first edition of Professor Hofman's "Metallurgy of Lead and Desilverization of Base Bullion"; was published in 1893; the fifth edition in 1898. In 1913, he published his work on "General Metallurgy;" this was followed by "Metallurgy of Copper" in 1914, and a revised and enlarged edition of the "Metallurgy of Lead" in 1918. "Metallurgy of Zinc and Cadmium" is now in press. He also published, through the Massachusetts Institute of Technology, "An Outline of the Metallurgy of Iron and Steel" for students' use. Since the founding of "Mineral Industry" in 1892, he has been continuously the annual contributor on the metallurgy of lead, and all Institute members know that his contributions to the TRANSACTIONS have been liberal in the extreme. It is through this medium that the results of the extensive research work, which he has always carried on in connection with his work at the Massachusetts Institute of Technology, have been published. Of the greatest importance are his papers dealing with the formation temperatures of slags, but many other metallurgical subjects have been covered.

Jan 1, 1921

By R Dimitrakopoulos, C Paduraru

The optimisation of mine complexes and related value chains is a challenging problem due to the simultaneous presence of a highly-dimensional decision space, integer decision variables, non-linear constraints and recovery functions, as well as geological and market uncertainty. In addition, if the uncertainty is revealed progressively, then decisions need to continuously adapt to new information, which poses additional challenges. Stochastic dynamic programming is a well-known class of methods for addressing problems where a decision-maker reacts to new information. While simplistic applications of dynamic programming using exact representations would be intractable for any realistic mine planning problem, new dynamic programming methods using approximate value function representations have been successfully implemented in the past to address problems of similar complexity. This work formulates the problem of mine complex optimisation as an approximate dynamic program and presents an application of the resulting method to a gold-copper deposit.CITATION:Paduraru, C and Dimitrakopoulos, R, 2014. Mineral supply chain optimisation under uncertainty using approximate dynamic programming, in Proceedings Orebody Modelling and Strategic Mine Planning Symposium 2014 , pp 415–422 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Nov 24, 2014

By D. O. DeGagné, J. F. Archibald

Spray-on polymer linings, as partial or full replacement for traditional forms of area rock support, have seen rapid growth in interest within Canada. A wide variety of lining types, ranging from polymer chemical to water-based cementitious materials, have been developed and commercially introduced to the underground mining market. Following approximately one decade of development work, several general conclusions have been reached regarding the performance of this class of area support media, these being that: health and safety assessment of the broad range of materials has shown the majority of them to be acceptable and safe for underground use; significant ground support potential can be offered by them, being equivalent to or better than capabilities offered by traditional support forms such as bolt-and-screen or shotcrete, and; their abilities to be rapidly deployed and provide near instantaneous support restraint offer considerable operational and cost benefits to underground operators. A review of currently available liner materials, their historic development within the Canadian mining industry, and overviews of support, health and safety, operational considerations and cost benefits are provided in this paper.

Jan 1, 2001

By R A. Stevenson

The purpose of this paper is to outline a recent development in ground fault protection. The paper deals with the A problems of both grounded and ungrounded systems, with regard to hazards to personnel and equipment, and shows that the increased sensitivity and speed of operation of this new detector results in increased safety to personnel and reduced stresses on equipment, and permits the detection of leakage currents before they become serious faults. The detector can be applied to all distribution systems, either A.C. or D.C., up to 15 kv., and the detector itself can be tested at regular intervals without interrupting line circuits. T HERE is always controversy among engineers as to whether distribution systems should be grounded or ungrounded. There are many experi-enced engineers on both sides of this controversy, and each have valid reasons for their choice

Jan 1, 1964

By P. H. Mell

THE little village, from which this formation receives its name, is situated on a bluff of the Alabama River, 175 feet above water level. This bluff is a portion of high table land that begins in the western portion of Choctaw and extends through Clarke and Monroe counties. We find points on this ridge more than 100 feet higher than Tuscaloosa, and nearly as high as the Tennessee River at Tuscumbia. Through this the Alabama River cuts its way, exposing a beautiful cross-section of the strata, of which the accompanying sketch may give some idea. The fossils are found about 75 feet below the surface and 100 feet above the level of the river. There are seven distinct strata. 1. The lowest, extending from the water's edge up the bluff 80 feet, is a soft calcareous rock containing about 15 per cent. of carbonate of lime, with occasional specks of mica. In this a few Ostrea, Turritellce, and Flustrce were found, but so friable as to fall to pieces when handled. 2. Next comes a stratum varying from 2 to 8 feet, consisting of

Jan 1, 1880

By James C. Fowler

The use of ground-probing radar as a reflection mapping tool is gaining acceptance in subsurface investigations. This tool may be used to obtain near-surface information useful to geotechnical engineers. Along with the lightweight field equipment now available, radar is being used to obtain information that may impact the safety and production of mining, tunnelling, and excavating operations.

Jan 1, 1982

By Andrej Šubelj

The paper tries to determine all which are interested or involved in collecting, evaluating, processing and distributing data on mineral resources, either "economic" or "uneconomic" and for what purposes. It shortly describes some of the most known classification systems, CMMI and UNFC, and their features, and discusses their advantages and weaknesses. Author also tries to define all the properties, a system should have to be declared as "World Code". Perhaps the ,integration of both systems would best accomplish the task and leave the “interest groups" the freedom to use only those parts of the system, they are interested in.

Jan 1, 2002

By M. R. Paterson, M. K. Suddaby

Operational and economic factors tend to favor the application of continuous processes in preference to batch processes in the majority of mineral processing applications. In this paper, the requirement for a continuous elution process is established and the development of a large-scale pilot plant is described. It is based on a continuous elution apparatus that has a number of special features. These are the subject of various patent applications. The apparatus is suitable for adaptation to the AARL, Zadra, and other methods of elution. The performance of the atmospheric continuous elution system (ACE) is concluded to have significant advantages over the batch process.

Jan 1, 1988

By Young-Dong Cho, Han-uk Lim, Bok-Ki Park, Sang-Eun Lee

Many methods and techniques have been developed to reduce ground vibrations. Some of them are an adoption of electric millisecond detonators with a sequential blasting machine and an improvement of initiating system with an adequate number of delay intevals.

Jan 1, 1995