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By Junji Shibata

It is important to recover and reuse the metal values contained in various industrial wastes in a viewpoint of environmental preservation. Most of industrial products are made through the processes to separate impurities in raw materials, solid and liquid wastes being necessarily discharged as industrial wastes. Chemical methods such as solvent extraction, ion exchange and membrane, and physical methods such as heavy media separation, magnetic separation and electrostatic separation are considered as the methods for separation and recovery of the metal values from the wastes. In this paper, some examples of the application of solvent extraction to the treatment of wastes are introduced. The treatment of solid wastes such as Ni-Co alloy scrap, Sm-Co alloy scrap, fly ash and flue dust, and liquid wastes such as plating solution, the rinse water, etching solution and pickling solution are accomplished using solvent extraction technique.

Jan 1, 1996

By Larry S. Diaz

The paper considers the selection of control instrumentation for a modern flotation plant, as well as the best interpretation and most effective use of the process data obtained. Process control computer availability is considered from the outset. A general philosophy of control is proposed which leads toward a system that is its own reliability monitor. The bulk of the problems are in grinding and classification. Alternative control methods are described that use particle size measuring devices. Flotation controls, based to a large extent upon on-stream X-ray analysis, are reviewed in detail. Reagent control methods are also examined. Methods to analyze the data obtained from the various measurement devices are introduced. These methods would enable an estimate of the validity of the data and require some redundant information. Another objective of these methods is the protection of operating equipment from possible control malfunctions. Although the discussion generally considers some degree of computer usage, this paper attempts to describe instrumentation and data analysis methods that enable control with or without the process control computer.

Jan 1, 1972

By A. C. Fieldner

The Sectional Committee on Classification of Coals, functioning under the sponsorship of the American Society for Testing Materials and the rules of the American Standards Association, in its 1934 report recommended to the American Society for Testing-Materials5 that Specifications for Classification of Coals by Rank be adopted as tentative. These specifications, slightly modified as recommended by the Sectional Committee, in its 1935 report,6 wore approved as tentative standards by the society in 1935. The specifications rover the classification of coals according to their degree of metamorphism, or progressive alteration, in the natural eerie s from lignite to anthracite. The basic scheme of classification is according to fired carbon and calorific value (expressed in B.t.u.) calculated to the mineral-matter-free basis. The higher-rank coals are classified according to fixed carbon on the dry basis, and the lower-ran]: coals according; to B.t.u. on the moist basis, that is, containing its natural bed moisture but free of visible surface moisture. Agglutinating and weathering indices arc used to differentiate between certain adjacent groups.

Jan 1, 1935

By James W. Reil

A test series of small, precisely-controlled and thoroughly-monitored production blasts was conducted at two quarries. In each series, all variables except delay were kept constant, as much as practically possible. The first aim of the study was to determine the effect of local geology on ground vibration. The second aim was to test several hypotheses relating the effect of millisecond delay intervals to fragmentation and ground vibration. A resonant frequency of ground vibration was shown to be related to the thickness of the overburden, in accord with a model proposed by Gupta (1961). Since the overburden geology creating this resonant vibration cannot usually be changed, two methods were tested to choose delays such that blast vibrations would destructively interfere. These were shown to be effective in modifying both the peak particle velocity and response spectra of ground vibration. The delay interval chosen also affects fragmentation, primarily in massive rock, with an optimum relief between holes of 2 ms/ft. Strain gage records indicate a possible mechanism consistent with this information.

Jan 1, 1985

By H. R. Hardy

Whether the mining engineer is concerned with stress problems in a mine at depth, the development of a new drill bit, or the efficiency of a comminution process, the mechanical properties of the rock with which he must work are of the utmost importance. One of the most popular topics in rock mechanics circles today is ?Is it possible to utilize directly parameters determined from laboratory tests on rock specimens in the analysis of mining engineering problems?? It is the author's opinion that laboratory and .field investigations have not yet reached the stage of development where this question can be answered with any degree of certainty. At present, great difficulties are involved in applying the results of laboratory tests to a mining engineering problem. However, this is due in part to the lack of detailed measurements of stress and deformation in the field and in part to the lack of development of satisfactory structural theories to correlate laboratory and field measurements. Furthermore, if mechanical properties measured in the laboratory are to be directly applied to the analysis of mining engineering problems, the critical mechanical properties must be identified, reliable test procedures must be developed and extensive test programs must be carried out.

Jan 1, 1964

By A. F. Roberts

The subject of mine fires is a very wide one. To give reasonable coherency, the paper concentrates on the behaviour of fires in the ventilated airways of mines; spontaneous combustions are not considered. The following topics are considered in some detail: 1) Material selection: Performance requirements for mining materials in terms of flammability and smoke/fume production; methods of test and need for relevance to mining conditions. 2) Fire growth: The influence of material properties and method of use on the rate of growth of fire in a mine roadway; the influence of ventilation, slope, material orientation, proximity of walls and roof on fire behaviour. 3) The fire in the ventilation network: The influence of fire on the ventilation distribution; the circulation of fire products in the network. The influences of these topics in determining fire control strategy are then considered but topics such as fire detection and fire extinction methods are not reviewed in detail. An extensive Bibliography on papers relating to mine fires is included.

Jan 1, 1989

By Lever R. R

The paper discusses assay methods generally used when prospecting for gold, and also the applicability of various chemical methods, it describes a new paper chromatographic technique.for making fairly rapid semi-quantitative assays for very fine gold. Testing of the method in field work shows that this simple method could have applications in geologic work, in prospecting and in certain routine mine sampling work. It is not yet a method that can be used to detect anomalies in traces of gold dispersed around an orebody, as is general practice in geochemical prospecting.INTRODUCTIONAccording to the English economist Harrod (1958), "the acute shortage of gold in the world-because currency value has not been adjusted in line with the fall in the goods value of the various currencies-has been a familiar fact for some time now". Harrod calculates that a rise in the price of gold to double its present value is necessary to rectify this condition, and that, if this rise were to take place, increase in production and reduction in private hoarding might well bring annual accretion to world stocks from the presentaverage of about $464 million to a figure close to the $2,000 million that would probably eiiminate these shortages.Any increase in the price of gold is bound to lead to a great increase in prospecting at working mines, in abandoned areas and possibly in untouched country. Prospecting, techniques for base metal orebodies have improved greatly in the last thirty years; but methods available to detect gold occurring without accessory metals have not received the same attention. With this in mind a paper chromatographic method of assaying for gold has been developed by Lever (1958). In the field this semi-quantitative method has proved...

Jan 1, 1959

By Ralph B. Stevens

The objective of this 20-month program was to define the relationships between mine ventilation, temperature, humidity, ore properties, material's used in mine operations, etc., and the spontaneous combustion problem in underground metal mines. Tradeoff studies of availability, reliability, cost, and maintenance of spontaneous combustion protection sensors and telemetry were conducted, after which a prototype system was selected from four design alternatives. This selected system was then laboratory tested and demonstrated in an underground copper mine.

Jan 1, 1979

By Richard S. Dennis

Acid recovery employs ion exchange (I-X) resin as separation media for inorganic acids from dissolved metallic salts by physical adsorption and without the use of chemicals. This technology has been used for years on spent etching and plating liquors to recover acid for reuse in the bath and to reduce waste acid neutralization costs. It is also used for electrolyte treatment to facilitate valuable metal recovery via acidity reduction. TETRA's ccrxr'" I-X contactor has been used successfully for acid separation from its metallic salt counterpart in a simple, continuous operating mode using strong base anion resins. Efficient separation is enhanced by acid reconcentration to nearly its original strength or as high as 14-20%. Continuous treatment also recovers heat to the tankhouse or bath and improves metal quality due to consistent acid quality. Conventional fixed bed ion exchange (I-X) systems are impractical for acid recovery because of complex control design and large resin inventories needed to process very low liquid-to-resin treatment ratios associated with strong acid concentrations.

Jan 1, 1996

By David A. Monaghan

On January 14, 1974 a fire occurred in the 3 East mains of the Joanne Mine of Eastern Associated Coal Corp. in Rachel, West Virginia. The mine was evacuated without injury and sealed completely at the surface within 24 hours. It was decided by the coal company along with the U, S, Bureau of Mines, the West Virginia Bureau of Mints and MESA that remote sealing of the fire zone would be attempted. This report summarizes the remote sealing effort and those activities directly related to the remote sealing effort. This chapter provides a brief history of previous remote sealing attempts, a description of the recently developed remote sealing system and a description of the Joanne Mine operation as it related to and affected the remote sealing effort.

Jan 1, 1975

By Terry L. Muldoon

This report describes development and demonstration of an upgraded stench fire warning system for underground wines. Current systems, which have been used since before 1920, release an ethyl mercaptan mixture into the mines' compressed and/or ventilation air during emergencies. Miners, when smelling ethyl mercaptan, evacuate the mine according to predetermined plans. These systems, while simple, have problems with safety and reliability. The upgraded system overcomes these problems. The system uses a different stench agent, is less toxic, less nauseating, and less corrosive than ethyl mercaptan. These combined with the feature of thiophane not reacting with iron oxides, makes the upgraded system safer and more reliable. The system also uses a combination of two simple principles: a standpipe with pressure balancing to provide a constant head, and a sized orifice to control the rate of release of the stench agent. This system enables the mine to release the agent for a longer period which provides better coverage and to ensure that miners will not be exposed to potentially toxic concentrations of the stench agent. The system is easy to operate, requiring only the turning of two 1/4-turn ball valves. The upgraded system has been successfully tested during two evacuation drills at an underground uranium mine. Using three injectors (one on the compressed air line and one on each of two intake air shafts), the system exhibited significant improvements in warning times over the mine's existing system. This report provides a detailed description of the system design and its demonstrated performance in two mine demonstrations.

Jan 1, 1981

By L. R. Stoiser

The mineral resource potential of the Los Bronces deposit was successfully evaluated by an intense, coordinated program over a 37-month period (April 1978-May 1981) as part of an economic feasibility study. The program included more than 120 km of core drilling, 63 km of access road construction under adverse topographic and climatic conditions, detailed geological mapping, plus other related activities. This Tertiary-age copper-molybdenum deposit is composed of an earlier mineralized porphyry-type body intruded in part by a large complex of mineralized hydrothermal breccia pipes. Both intrusive and extrusive igneous rocks are present. Erosion, oxidation, leaching, and supergene enrichment of copper have resulted in a deposit now exposed at the surface that contains more than 368 Mt grading about 1% copper equivalent as sulfides.

Jan 1, 1982

By W. M. Williams

The Canadian steel industry is now in many ways a mature one, having achieved many technical successes during its hundred-year history. It is interesting to look back over this period, to learn something of the histories of the different producers and of the people and forces that shaped their development. The following article provides a thumbnail sketch of the Canadian steel industry as it exists today. It is intended for the general reader, not for the specialist who will want to consult the several books and theses written on the development of the industry during the last hundred years. The famous Les Forges du Saint-Maurice, an important iron producer for a century and a half, provides a natural historical starting point for a look at the four major players - Dosco, Algoma, Stelco and Dofasco - who have provided most of the hundreds of millions of tonnes of steel, in every form from horseshoes to tinplate, needed in the twentieth century. The smaller companies which have sprung up in the last 20 or 30 years are dealt with briefly - but only because their history is so recent. Not so long ago the mini-mill, based on scrap rather than on the blast furnace, was thought to be specially suited to the economies of the smaller developing countries of the Third World. However, recent history has made it evident that the small plant, specializing in a few basic products (e.g. reinforcing bar) or taking advantage of special circumstances, can successfully compete with the large blast furnace/primary steel producers.

Jan 1, 1999

The scope of this paper is to introduce a mathematical model based on matrix algebra in order to determine similitude quantities, which can be arranged in specific formats to simulate the field conditions and associated behaviour. The formulation of a typical mathematical model applicable to Geomechanics is demonstrated here. The examples provided are intended to facilitate comprehension and application of the proposed model in practice.

Jan 1, 1989

By Michael J. Klishis

West Virginia University researchers examined risk and exposure in the roof bolter operator's job and developed approaches for preventing accidents and for evaluating system and human performances that may be appropriate as a general application to improve safety and efficiency in the industry. Using a microanalysis of accident data and underground observations, the researchers classified bolting injuries within one of four work routines: 1) drilling bolt holes; 2) bolt installation; 3) machine tramming, (re)positioning and setting the ATRS; and 4) general face preparation. Time and motion studies were then combined with injury data analysis to develop risk and severity indices, as well as a severity-weighted index that served to determine the degree of risk and exposure by work routine. More than two dozen bolting-related problems were identified as potential situations that could lead to injuries or expose workers during their job. Approaches to avoid these situations were suggested and then applied at six mining operations to evaluate specific problems in roof bolting operations. These suggestions encompassed the three E's of Safety (Engineering, Education, and Enforcement) and emphasized the analysis of worker behaviors that lead to human error accidents.

Jan 1, 1993

The optimum cut-off grade policy maximizes the net present value (NPV) of an open pit mining operation subject to the mining, processing, and refining capacity constraints. The traditional approaches to cut-off grade determination ignore the escalation of the economic parameters such as metal price and operating costs during life of an operation, and consequently lead to unrealistically higher values of the objective function. Further, the NPV of a mining operation declines due to the depletion of the available reserves, causing a decline in the optimum cut-off grade, i.e. higher cut-off grades in the early years of an operation and lower cut-off grades during the later years. Hence, low grade material mined in the earlier years may be stockpiled for processing during later years to offset the effect of escalating economic parameters on NPV. This paper demonstrates the combined impact of introducing economic parameters, escalation and stockpiling options into the cut-off grade optimization model. The model promises an enhancement in NPV as illustrated in a case study incorporating practical aspects of an open pit mining operation.

Jan 1, 2011

By C. Frenzel, N. Blechschmidt

"INTRODUCTION There is no doubt about the time and effort companies put in establishing and maintaining their equipment. However, the question about how these companies can map the benefits comes up. Neither do they have the tools to quantify the benefit of their action, nor do they have the tools to know the actual quality of their current maintenance system. The resources used in the process seem futile to observers. It seems impossible to trace improvements and to get information about the impact of actions in retrospect. Improvements in maintenance performance cannot be recognised by management or shareholders. Thus the necessity for measuring the performance of maintenance systems is given. In this paper ConMoto is systematically showing the strengths and weaknesses of many companies' maintenance management and is providing field-tested proven design elements for measuring maintenance systems and implementing Value Oriented Maintenance. Considering only business assets in production facilities and related machinery out of all investment goods in Europe, you reach a value of around 9.7 trillion euros in 2008. In Germany alone the equipment replacement value amounted to about 1.9 trillion euros [8,10,11,13]. If you calculate a cross sector maintenance costs rate of 4.8 % (corresponding to the average value identified in this study), direct maintenance costs in European production locations add up to over 450 billion euros per year [3]. These figures speak for themselves. Yet maintenance is not only of enormous significance for European enterprises. Our experiences show that maintenance and asset management, particularly sustainability issues, are also increasingly moving to the forefront in the BRIC states, in the Middle East and in many emerging countries. First of all, in order to meet the resulting high quality and cost related requirements of maintenance systems, a comprehensive overview of the issue is needed. This overview is provided by a detailed analysis of 83 companies and production plants from various sectors – with amazing results. SIGNIFICANCE OF MAINTENANCE Current studies show the high financial significance of maintenance and asset management. According to the market study in the Asset Manager [9], in industrialised countries about 10 to 15 per cent of the labour force are employed in maintenance and facility management tasks. In Europe about 40 to50 million people are directly and indirectly involved in retaining the value of machinery, plants, buildings, transport systems and infrastructure facilities. A glance at the costs side also demonstrates the great relevance of maintenance. EU-wide annual direct maintenance costs amount to a total of more than 1,500 billion euros. In Germany alone they are about 250 billion euros. This impressive total is considerably exceeded by indirect maintenance costs caused by technical failures. Indirect costs are estimated to be five times higher (Figure 1). [7,12,14]"

Jan 1, 2018

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Jan 1, 1980

By Richard C. Moore

The U.S. Bureau of Mines contracted a study to review the air and water monitoring requirements of five Federal environmental acts (the Federal Water Pollution Control Act, the Safe Drinking Water Act, the Clean Air Act, the Surface Mining Control and Reclamation Act, and the Resource Conservation and Recovery Act) and to compile information on the currently available monitoring instruments. A literature review of the acts and their associated regulations was conducted to determine applicability to the mining industry as well as any air and water monitoring requirements. In addition, an industry search and literature review was performed to assess the instrumentation available to comply with the monitoring regulations. Based on this research, the instruments are classified by general applicability to air, surface water, or ground water monitoring, then catalogued by monitoring parameters. A discussion is provided on recommended and innovative monitoring techniques.

Jan 1, 1981

By J L. Mauk

The Martha epithermal Au-Ag deposit contains multiple generations of quartz veins with a range of textures. We examined: +        vein textures, +        crosscutting vein relationships, and +        the paragenetic sequence within the pit walls as well as a wide range of hand specimens. Samples include host rock, breccia, and veins, but these groups are not distinct; instead, they form a continuum.   Veins at Martha mine show a wide range of textures on a local scale; these textures also change significantly over both the lateral and vertical extent of the pit. Common textures include crustiform bands, comb quartz, colloform bands, platy quartz, massive quartz, drusy quartz, sedimentary textures and brecciation.   Vein grades relate to textures. Many textures, including crustiform, platy, cherty, and sedimentary textures display predominantly low grades, but some textures are linked with high grades, such as ginguro, massive and comb quartz where they are associated with visible base metal sulphides and/or electrum. Host rocks and most breccias are low grade, as most samples contain <2 ppm Au.

Jan 1, 2006