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By David van Cleave, David L. Rome

Whether you buy your minicomputer from a manufacturer or another vendor, the first thing you must do is define your needs. With good planning, the initial cost will be low and your return on investment will be maximized over the long term. Involving all members of your staff who will he using the new computer in the planning phase is also important. Their participation will alleviate any potential concerns they may have about new equipment, and their suggestions will provide valuable input for your specifications. After you define your proposed system, survey available hardware and software. The survey will help you in the next step, preparation of specifications. The specifications, along with a quote request, are then sent to various manufacturers. Consider the Manufacturer When selecting your minicomputer, one important item to consider is the manufacturer. Remember, when you buy a computer, you're also buying the services of a computer company. A firm that makes a commitment to its customers and provides a product that is field tested before releasing it for sale is preferable. Examine the company's maintenance and support packages, since every machine requires preventive maintenance. Does your manufacturer or original equipment manufacturer (OEM) support service sites in your area? Has their service record been commendable? Will they provide training for your personnel and a supply of circuit boards so you can retain a degree of self-service autonomy? Three methods of buying a computer involve the manufacturer, an OEM, and the systems house. Buying direct from the manufacturer means you go straight to the source, using no middleman. This gives you maximum flexibility; you can consider every alternative and many possible combinations of computers, peripherals, and software until you find exactly the right system for you. The OEM buys computers direct from the manufacturer and builds them into his own computerized, special purpose product. He usually sells a complete package, including software and hardware, and often noncompetitive equipment as well (a scientific or engineering instrument, for example), designed for the mining market. Because he offers a packaged product, the OEM can often charge less for the system than if you put the pieces together yourself. In many ways, the OEM also provides a unique system. And while the OEM sells a packaged solution, he also usually has the special market knowledge necessary to modify the system to meet your unique needs, if necessary.

Jan 11, 1981

By Golledge P

Safety legislation has a long history and widespread application, but how can one test its effectiveness? One way is to examine safety statistics. Another way is to compare the legislation with principles of good safety practice. Mine safety legislation contains many features that are widely accepted, and these should be examined critically to determine their importance. Uniform legislation and revision of legislation should be considered. INTRODUCTION

Jan 1, 1975

Discussion of the paper of Robert Henry Lee, presented at the New York Meeting, October, 1913, and printed in Bulletin No. 82, October, 1913, pp. 2515 to 2522. J. E. JOHNSON, JR., New York, N. Y.:-This subject is of great and increasing importance, as the exhaustion of the deposits of ore of ideal character compels the iron industry to turn more and more to those which are less desirable on account of physical structure as well as analysis. Thus there has come about the use of the Mesabi ores in this country and also of the Minette ores in Europe, which produce far greater percentages of flue dust than did the lumpy ores first used. It is a matter of common knowledge that the utilization of this flue dust, containing commonly 50 per. cent. or more of metallic iron, has been a problem very difficult and tedious of solution. The number and variety of the solutions now offered is a sufficient proof of this. . I have no intention of going into the merits or demerits of any of these processes as such, but there are certain considerations concerning the effect of their product on the operation and fuel economy of the blast furnace which I believe to be new and which I desire to bring out. There are two methods, so different as almost to be direct opposites of each other, whereby an ore may exercise an unfavorable effect on the economy of the blast furnace. The first of these is well known and results from the ore being refractory and highly resistant to the action of the reducing gases of the blast furnace. This results in its being incompletely reduced when it reaches the zone of fusion and in the reduction being finished by the direct action of carbon in the lower portion of the furnace. This is so well understood as to need little elaboration or comment. There is, however, another action which may be equally as fatal to the economy of the furnace as the foregoing, and as this point is, to the best of my knowledge, not generally appreciated, it is one upon which I desire to lay particular stress. This consists in the ore being, in a sense, too reducible.

Jan 12, 1913

By R Wynn, R A. Pax, S Mann, B Cornish

The semi-autogenous grinding (SAG) mill at the MMG Century operation has failing load cells that are essential to the control strategy used to stabilise the mill. Currently, mill-bearing pressure is used as a proxy for the load cells, but it has been found to be a noisy signal and lacking in useful sensitivity. It is also prone to variations and drift due to temperature. After consideration of a number of options, a non-contact acoustic array has been installed around the SAG mill to provide a more stable proxy load signal as well as other information about the internal operation of the?mill.The installation consists of 12 microphones to provide some detail into the operational differences that occur during normal operations at the MMG Century SAG mill. This acoustic approach acknowledges that operational grinding mills emit significant acoustic emissions that are a consequence of the dynamic environment prevailing inside them.Previous studies have attributed the acoustic noise to a range of events that occur inside these mills (Pax, 2011; 2012). Consequently, non-contact acoustic determinations of in-mill behaviour can provide powerful insights into the operation of the primary comminution tumbling mills. By measuring key microphone signal attributes at different positions around a mill, a holistic picture of mill internal operation can be developed.This paper will describe the installation of the 12 microphones and discuss the use of the acoustic load signals as a proxy for failing load cells. It will also present data from new observations of internal mill dynamics and the results of implementation of control using these acoustic signals. Key to the control approach has been the development of a logically coherent picture of the processes inside the mill.CITATION:Pax, R A, Wynn, R, Mann, S and Cornish, B, 2014. Implementation of acoustic arrays for semi-autogenous grinding mill?operation, in Proceedings 12th AusIMM Mill Operators’ Conference 2014 , pp 273–282 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 1, 2014

For the convenience of members who may be traveling from place to place, the Secretary has compiled a list of libraries or other places in the United States and foreign countries where MINING AND METALLURGY or the Transactions may be consulted. This list will be. sent to members if they so request. LIST OF THE MEETINGS OF THE INSTITUTE AND THEIR LOCALITIES FROM ITS ORGANIZATION TO MARCH, 1920

Jan 1, 1925

By C. Kleine

Coal sorting with an x-ray-transmission (XRT) sensor has experienced a lot of development since first described by Jekinson et.al. in 1974. Powerful computers and increasingly sensitive X-ray scintillation counters enabled the development of high-performance sensor-based sorting machines. The first industrial installation of a belt-type XRT-sorting for coal is in operation since 2004. It is upgrading high quality coal from 1% ash to 0.7% ash for cathode production. In comparison to the high quality coal which is treated with a belt-type sorter, the chute type sorter has been successfully optimized for high volume coal treatment of lower quality coals. This project was funded by the German Environmental Fund (Project Nr.244444). In cooperation with the RWTH Aachen University and Isambane Processing, CommodasUltrasort(now Tomra Sorting Solutions) conducted extensive pilot test work under production conditions in 2010 for the destoning of power station coal at Arnot Power Station in South Africa. The experience gained during this pilot test phase led to an optimized, redesigned PRO Secondary XRT Chute sorter which is now in operation at a South African coal mine. This flexible semi-mobile modular destoning plant is treating a size range of -120 mm +30 mm at a throughput of 150 tph. The implementation of this plant not only reduces the ash content, abrasiveness index and sulfur content significantly, but also reduces royalties, water treatment and transport costs.

Sep 1, 2012

By Andreas Zielonka

To meet the increasing demands of the quality and long term stability of technical systems also the applied materials have to full fill higher standards. This is of special importance where the function of a whole system depends on the reliability of the used materials for example for connector systems in automotive, computer and other electronic equipment?s. In most cases for connector systems electro deposited top layers are applied. To improve the quality of the applied layers new electro deposited systems are developed. One important field of research are the development of composite materials as dispersion coatings and multilayer systems. Multilayers are systems with a high number of single inter-layers of different metals or alloys with the wide chance of the alloy composition. As gold is one of the most important contact material for high quality connector systems it is used as basis for the development of multilayer systems. For the electrodeposition of multilayers two different methods can be applied, the single and the dual plating process. As in the dual plating process two different electrolytes are used, the single plating process allows the formation of multilayers from one electrolyte. In the presented research results cobalt and nickel are used besides gold for the formation of the multilayers. The properties of the layers can be influenced in a wide range by the change of electrolyte composition and the process parameters as current density, current waveform, temperature, hydro-dynamic conditions at the electrode surface and by the number and thickness of the inter layers of the deposited materials. The paper describes the fundamentals of the electro deposition of multilayer systems. For the investigation of the properties of the multilayers different techniques are applied. One of the most important parameter are the thickness of the total layer and of the applied sublayers. The thickness of the sublayers can be varied between a few nanometers up to micrometers. The wear resistance, the contact resistance and the plug-in forces are measured as these parameters are important for the technical application of such layers. For the description of the structure composition and surface properties the sample where also investigated by scanning electron microscopy (SEM), energy dispersive x-ray-analyses (EDX) and glow discharge optical spectroscopy (GDOS). The paper shows that the deposition of gold based multilayers is possible and that the properties of such systems can be varied in a wide range what opens new fields of applications of such materials.

Oct 1, 2003

By John A. Graves

Anaconda's Jackpile-Paguate mine, located between Albuquerque and Grants, N.M., is situated at an elevation of 6000 ft in a semi-arid desert region. The original Jackpile deposit was discovered by Anaconda air and ground exploration parties in Nov. 1951. A large percentage of the uranium mined in New Mexico comes from the Jackpile-Paguate, which is one of, if not the largest, open pit uranium mines in the world. From 1953 to the present, 120 million tons of overburden, mining waste, and low-grade material have been removed to produce approximately 10 million tons of merchantable uranium ore, having an average grade of about 0.25% uranium oxide. Identifying the Orebody Surface drill holes delineate the ore bodies on a predetermined grid which varies in dimension but usually affords 100-ft control. These holes are probed immediately after drilling by geophysical logging trucks, resulting in a gamma log and digital readout from each hole. From this information it is possible to arrive at an almost immediate conversion to percentage of U3O8 on 6-in. intervals. Initially a hole is probed at a reconnaissance speed of 10 fpm with a time constant of 8 sec. Wherever the gamma recording goes off scale on an initial run, that particular zone is rerun at 2 fpm and at a time constant of 2 sec. This time constant is the interval that emissions are counted and accumulated for recording purposes. The search radius of the Geiger probe is approximately 18 in.

Jan 8, 1974

By R. Padilla, M. C. Ruiz, R. Villa

"Bismuth is an impurity in copper minerals where it occurs mainly as the mineral bismuthinite (Bi2S3). In smelting of copper minerals, most of the bismuth reports to the white metal, as a result, a substantial amount of bismuth accompanies the copper to the electrorefined cathodes. Thus understanding the behavior of Bi2S3 at high temperatures is crucial to eliminate bismuth before electrorefining. In this paper, some experimental data on the decomposition/volatilization of bismuthinite in nitrogen- oxygen atmospheres is discussed. The results indicated that in nitrogen atmosphere, bismuth volatilization occurs through a fast decomposition of bismuthinite to metallic bismuth and sulfur with subsequent volatilization of bismuth in the range 850-1100 °C. Similarly, in the presence of oxygen, bismuthinite decomposes to bismuth too, followed by oxidation to the non-volatile bismuth trioxide at temperatures higher than 750 °C. Both, temperature and partial pressure of oxygen affect significantly the bismuth volatilization and the oxidation rates.IntroductionCopper sulfide minerals are the major source for the production of metallic copper by pyrometallurgical processes, which are the dominant processes in the production of copper by selectively oxidizing the sulfide sulfur to SO2 and the accompanying iron in the concentrates to iron oxide, which can be conveniently removed as a stable slag.Generally, copper concentrates contain some deleterious minor elements such as arsenic, antimony, bismuth and lead, which are present as sulfides. These elements depending on their concentration may originate problems in the copper smelting processes and they can ultimately lead to a final copper product with unacceptable high levels of impurities.During the treatment of these copper concentrates by smelting, the impurities generally distribute themselves in the condensed and gas phases and they are eliminated mainly through the gas phase [1-3]. Thus, smelter off gases contains substantial amounts of volatilized impurity elements. For example, in the case of bismuth, the estimated distribution of bismuth in flash furnace smelting [2] was 15 % in the matte, 5 % in the slag and 80 % in the gas phase, and recently, for Outokumpu flash smelting Davenport [3] reported the distribution of bismuth as 30-75% in matte, 5-30% in slag and 15 -65 % in the off gas."

Jan 1, 2011

By Alton B. Cook

In the Scurry Reef field, Scurry County, Tex., a study was made to determine the physical properties of the oil in all parts of the reservoir by a new method developed for this study. The method involved correlation of data from a survey 1 of the gravity of the produced oil, from measurements of gas-oil ratios on key wells selected to give representative data for the entire reservoir, and from laboratory analyses of reservoir oil samples. A field survey was made of the API gravities of the produced oil by testing oil samples from 107 key wells. Precise gas-oil-ratio tests were made on 45 key wells that were producing under comparable separator-operating conditions. Subsurface-oil samples were obtained from seven wells, selected to provide reservoir oils ranging approximately from a minimum to a maximum in saturation pressure. The physical properties of the subsurface-oil samples were determined, and correlations were made of these laboratory data with the field gas-oil-ratio test data. These correlations were then used to estimate physical properties of the oil throughout the reservoir. A logical procedure of determining the variations in physical properties of reservoir oils in most fields is to obtain and analyze subsurface-oil samples from enough key wells to provide an ample coverage of the field. Under this procedure, data from a large number of samples would be needed to provide the desired information on the Scurry Reef field, as it is one of the largest known in the United States.

Jan 1, 1955

President Mrs. Herman A. Prosser 1001 Park Avenue New York 28, N. Y First Vice-President Mrs. David E Park 115 East 67th Street New York 22, N Y. Second Vice-President Mrs Oliver Bowles 5000 Massachusetts Ave , N W. Wash 16, D C Third Vice-President Mrs. H Bobinson Plate 1215 Vancouver Avenue Burlingame, Calif

Jan 1, 1952

Historical Background. South Africa's industrial history began with the discovery of gold and diamonds during the last century, and the mining industry was the first chief component of our technological development. During the past six decades, quantum leaps were made in other fields, too, when other industries and research bodies such as Escom, NDC, Iscor, Sasol, Foskor, Alusaf, Mintek, cs I R, SA B S, and A E C were established. These meaningful additions have two outstanding characteristics. Firstly, they were linked mainly to primary activities such as energy and minerals and, secondly, their establishment was to a large extent due to the driving force of individuals such as Van der Bijl, Van Eck, Rossouw, Schonland, and Roux, rather than to impersonal government policy. Encouraging signs of the evolution of such policy has emerged during the past few years.

Jan 1, 1989

By J. A. Wates

The paper examines the consequences of dam building with slime of high water content, and therefore Iow relative density, such as the tailings usually associated with the extraction of uranium. It shows how a Iow relative density reduces the practical maximum rate of rise, and hence the establishment cost, of slimes dams built by conventional means. Further hidden costs of such tailings dams are examined. It is concluded that dewatering of tailings before their disposal is the most cost-effective means of increasing the rate at which a particular dam can be constructed, or of reducing operating or stability problems on existing dams. In the longer term, underground disposal seems to be a feasible alternative. However, it is pointed out that there are other factors that can compound the operating difficulties, and that these should be investigated before remedial steps are taken.

Jan 1, 1983

By R. L. Anderson

Mechanical cleaning of bituminous coal in the United States was begun about 1875, with plants in western Pennsylvania and Illinois. The United States Geological Survey began to record the quantity of washed bituminous coal in 1906; and the series was carried forward to 1923, except that no data were collected, for 1922. This statistical work was transferred to the Bureau of Mines in 1925, and the collection of data on mechanical cleaning was resumed in 1927. Data collected before 1927 include only the coal that was washed at the mines and do not include that cleaned by pneumatic methods at the mines and that cleaned at central washeries operated by consumers.2/ The total bituminous coal washed in 1906 was less than 10 million net tons. In 1927, the first year for which complete figures are available for all types of mechanical cleaning, 28 million net tons of bituminous coal were cleaned in the United States.

Jan 1, 1951

MR. MARGOLF: Our final speaker this afternoon before we have an opportunity for some questions for the members of the panel, is a gentleman who has spent more than 40 years in the newspaper industry. He started out as an office boy while he was still in high school. He worked his way through college working for a newspaper in Lexington, Kentucky where he graduated from the University. He has a long association with the Albuquerque Tribune but what brings him here today is in his position as editor of The Rocky Mountain News which is certainly one of our largest circulations. I think it is the largest circulation newspaper in the Rocky Mountain states. Ralph Looney, in that

Jan 1, 1982

By C. Schwandt

Recent research work has led to the development of a new electrochemical hydrogen sensor, which is based on a proton conducting solid electrolyte in conjunction with a self-contained solid hydrogen reference standard and is operated at elevated temperatures. The incorporation of the internal hydrogen reference renders the sensor versatile and user-friendly and makes it attractive for practical exploitation. The present article focuses on the utilisation of the sensor as the integral part of a probe for the quantitative determination of hydrogen in molten aluminium and aluminium alloys. The main features of the sensor and the probe as well as the measuring technique are discussed. Experimental results obtained with the novel analyser in trials under industrial conditions are presented and highlight the good performance of the device.

Jan 1, 2003

An optimization process is described that can be systematically applied by mine planners to produce life-of-mine schedules aligned with their strategic targets, while maximizing the net present value of the mining operation. The software tool employed uses heuristics and an evolutionary algorithm to generate life-of-mine schedules of production and development activities. Generating such schedules is typically a very difficult task due to the large number of operational constraints that must be respected, and the vast number of alternative schedules; as a result the value of the mining operation can be compromised. With an expansion at Newmont?s Leeville mine in Nevada, the mine planners were given the task of producing feasible life-of-mine schedules with significantly increased production rates. Their initial efforts indicated that it would be a considerable challenge to generate such schedules in a timely manner. By systematically applying the proposed optimization process, the mine planners were able to generate optimized life-of-mine schedules with the desired production rate.

Aug 1, 2013

By Kouji Mimura, Tamas Kekesi, Yongfu Zhu, Masahito Uchikoshi, Minoru Isshiki

"The formation and anion exchange sorption of chloro complex ions can offer a great potential to be utilized for the separation and purification of metals in aqueous solutions. Available stability data were primarily used to estimate the predominance of chloro complex species, indicating the feasibility of such separations. Anion-exchange sorption functions, describing the equilibrium distribution of a number of important elements have been determined by the batch equilibrating method in the practical HC1 concentration range. Various oxidation states were stabilized by the addition of appropriate agents. Tendencies in oxidation, complex formation and anion exchange sorption were confirmed by spectrophotometric investigations. Based on the fundamental results, anion exchange processes have been developed for the purification of iron, cobalt, copper and zinc. The efficiency of separation was assessed and the procedure optimized by the analysis of experimental elution curves. Results have demonstrated that by properly controlling the oxidation states and HC1 concentrations, practically all the impurities can be eliminated. Computer programs have been developed to estimate complex formation and redox equilibria, to screen and correct analytical data, to determine distribution coefficients and to evaluate efficiencies of separation.IntroductionBase transition metals have long been used as the staple materials in various fields of industry. In general, there has been an increasing tendency in purity requirements but recent advances have created a rapidly increasing demand for ultra-high purity metals. To give a few examples, ultra high purity copper can be used as bonding wire and interconnection in integrated circuits, or as material for superconductor stabilizing, high-field magnets, beside its use in cryogenics and ultra high vacuum technology [1]. Iron holds promises as a constituent element in the ß-FeSi2 material to be applied in new opto-electronic devices [2] and it is currently used, together with chromium and manganese, in the production of special magneto-optical materials for digital recording. The use of ultra high purity manganese and chromium in semiconductor technology is evolving. Although not considered a transition metal, zinc is also treated here because of the major significance in compound ZnSe semiconductors [3], and the possibility to purify it by the anion exchange method."

Jan 1, 2000

By G. G. Barbante

Copper anode slimes are a valuable source of the precious metals, and selenium and tellurium. They are mineralogically complex and this has led to a great variety of process flowsheets for treating them. The traditional pyrometallurgical method utilises oxidation in a reverberatory furnace, but has numerous shortcomings. Recently deep-bath intensive smelting methods have been developed for use in the larger refineries. Despite these process advances, the thermodynamics of the reactions involved remains poorly understood. An initial description of the thermodynamics of slimes smelting is presented, but is severely limited by a lack of basic data. It is shown that slimes smelting is superficially similar to copper converting, but has many unique features. More basic thermodynamic data on selenium-based systems are needed before the process model presented can be further refined, and work in this direction has already commenced.

Jan 1, 1994

By Vernon Read, John K. Hayes

Generally speaking, drilling equipment and techniques presently in use are not capable of meeting the complex technical-and economic-requirements of deep core drilling. Drilling to great depths involves increasing risk, time, and money. And it is especially true that costs increase with depth when conventional core drilling methods are used. Introduction of wire-line drilling techniques has been a great boon to deep core drilling, and is rapidly gaining general acceptance. But, in spite of recent progress, there remains a great need to improve productive drilling time and penetration rates, and still maintain high core recoveries.

Jan 1, 1959