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By Denise Crocce Romano Espinosa

The recycling of waste of electric and electronic equipment (WEEE) is one of the main modern challenges. Among the variety of WEEE, batteries can be set apart due to their composition and their growing demand along with portable devices. The objective of this work is to characterize the thermal behavior of a sample of mixed types of batteries using a thermobalance (TGA). The results of tests showed that Cd evaporated up to 800ºC, Zn evaporation occurred mainly above 900ºC and manganese oxides were pre-reduced to MnO at temperatures above 900ºC.

Jan 1, 2009

By J. W. Thompson

ESTATE IN MINERALS. Minerals beneath the surface may be made the subject of separate ownership either by a grant of the minerals by the owner of the land or by a grant of the land excepting the minerals, and thereby an estate in fee simple is created in the minerals, as corporeal things real. Colby, In re, Iowa, 169 Northwestern 443, p. 444. DEEDS EXCHANGING DIFFERENT MINERALS-RIGHTS OF PARTIES. The lands of two adjoining owners were underlaid with cement rock and clay at a depth of about 100 feet from the surface and with coal veins some 600 feet below the surface. By an exchange of deeds one of the land owners conveyed to the other the cement rock and clay with the right to mine and remove the same without entering upon the surface, but the deed contained no covenant not to injure the surface. The other deed conveyed the coal seam and so much of the rock and other minerals just above and below the coal as might be required in connection with the mining and removing of the coal, together with the right to mine and remove the same, and the adja- cent rock, clay, and other minerals, without entering upon or injuring the surface, with one immaterial exception. The deeds do not define the word "surface" and neither expressly nor by implication did they secure to the coal owner the right to subside the overlying cement rock; but the implication is to the contrary, as the deed gives the right to mine and remove coal without entering upon or injuring the surface. The provision that the coal owner should not enter upon or injure the surface amounts to a clause that the coal mine. shall not be worked so as to let down the surface and this does not create any inconsistency with the provision giving the right to mine and carry away the coal.

Jan 1, 1919

By James W. Wade

This paper describing the mining practices at the Tintic Standard mine is one of a series being prepared by the United States Bureau of Mines. In the preparation of this paper each subject has been presented by the engineer in charge. L. R. Dobbs wrote the part pertaining to tae technique of square-set mining, J. M. Snow the part on geology, and M. D. Paine, the part on ventilation. All of the drawings are the work of H. W. Waterfield of the engineering department. The statistics of the Tintic district ware prepared by A. G. MacKenzie. Each writer has attempted to show the difficulties that arise in operating and the practices used to overcome them.

Jan 1, 1930

By L. M. English, Y. J. Wang

When plotted as head vs. volume, fan curves start high and decrease in head with increasing volume while mine head curves start low and rise with increasing volume. Their intersection is the system operating point. But wait a minute: Isn't head loss a negative number, a debit? And isn't fan head an energy addition, a credit? This, as every ventilation instructor knows, is often a stumbling block to student or audience comprehension. It is possible to use the intuitively correct curves - pressure losses as negative values and energy additions as positive values-and still obtain the correct operating point: adding the two curves produces a third curve that intersects the x-axis at the operating point, the point at which the fan energy input exactly matches air circulation energy loss. Using this technique also makes it easier to account for outside influences on the system, such as natural ventilating pressure; with the standard approach it is quite easy to add or subtract such influences to the wrong curve. This approach can be extended to the graphical solution of any series/parallel circuit or ventilation network. The results are the same, and the approach is logically consistent and less confusing.

Feb 24, 1997

By G. Montes-Atenas

Throughout the years, research studies have reached a consensus in acknowledging the relevancy of surface chemistry phenomena on minerals separation and metals extraction. Many techniques, and notably, scanning electron microscope-based technologies have revolutionised the entire mineral processing industry. Nevertheless, the comprehensive understanding on how surface chemistry properties influence the performance of many processes involving ores is still a challenge, a matter of controversy. The latter is mainly due to the fact that all interfacial processes do not necessarily require stoichiometric and well defined atomic structures. This is particularly true in the case of sulphide minerals which are well known to be superficially unstable in aerated media. When trying to measure any variable related to mineral-mineral or mineral-aqueous solution interfaces, there are too many unknowns regarding how sensitive the interface is when facing sampling protocols and sample handling. The aim of this research work is to make a case for improving future concentrators? survey protocols. It suggests a methodology to study effectively chemical changes at the outmost mineral surface layer at different stages of a mineral processing operation. The sampling protocol and sample handling is presented in details and it is applied to the regrinding stage of an industrial plant.

Feb 27, 2013

By Steve Dillingham

The explosives business by nature is providing a specialized, valued service and associated products to a variety of customers whether mine, quarry or construction related. The level of performance demanded by the customer will typically coincide with his or her individual needs. Some will seek out the skills and knowledge of a blasting expert, while the focus of others is simply on production amounts.

Jan 1, 2003

By A. R. T. Denues

Liquid oxygen explosives are ordinarily made from a carbonaceous absorbent and from liquid oxygen of high purity. These explosives have a limited but definite field of usefulness; their properties have been described in the literature, which includes several publications of the Bureau of Mines, the most recent dealing with fire-retardant treatments.3/ It seems generally conceded that the outstanding hazards in the use of these explosives are their high inflammability and their relative sensitivity to mechanical action. Each of these topics has been studied, and some interesting practical results have been obtained. Treatments have been described[7] that render liquid-oxygen explosives prepared from granular carbonaceous absorbents practically immune to the action of igniting agents representing or exceeding practical hazards in violence.

Jan 1, 1941

By Steve Wiig

In 1987, the Rock Springs, WY district office of the US Bureau of Land Management (BLM) began to develop an automated system to store, maintain and manipulate more than 14,000 drill hole logs contained in the district's office files for various solid leasable minerals. The development of this system was based predominantly on a trial-and-error basis, with many procedural changes incorporated over time. The current Automated Drill Hole Database and Analysis System will continue to evolve with new software developments and increased personal expertise in this field. The mission of the BLM's Branch of Solid Minerals is mandated by a series of federal laws. The most important are The Mineral Leasing Act, the Federal Land Policy and Management Act, the Federal Coal Lease Amendments Act and the Surface Mining Control and Reclamation Act. Several regulations, promulgated from these laws, dictate that BLM must perform certain tasks and functions as part of its specific duties. The regulations that apply to the BLM Solid Minerals program are codified at 43 Code of Federal Regulations (CFR) 3400 for coal, and at 43 CFR 3500 for non-energy solid leasable minerals, such as sodium, phosphate and potash. Specific functions required of the Branch of Solid Minerals necessitates the use of geologic and drill hole data analyses. These functions can be divided into pre-lease and post-lease. Examples of pre-lease functions that normally require some level of drill hole data analyses include:

Jan 1, 1992

By L. E. Cardwell

This publication contains routine analyses and related source data for 475 natural gas samples from 17 States and two foreign countries. Of this total, 454 samples were collected during calendar year 1971. The remaining 21 samples were collected during previous years, but releases granting permission to publish the analyses were not received until 1971. All samples were collected as part of a continuous survey of the free world for occurrences of helium in natural gas. This survey has been conducted in the United States by the Bureau of Mines since 1917. In late 1965, the survey was expanded to include foreign gasfields. The analyses published herein were made by mass spectrometer and a special helium analysis apparatus, which are described in Bureau of Mines Bulletins 4863 and 576.4 Thirteen previous publications have presented the results of 9,427 gas analyses prior to 1971. The first three, Bulletins 486,5 576,6 and 617,7 contain analyses and related source data on 5,218 gas samples collected from

Jan 1, 1972

By William E. Ford, Edward Salisbury Dana

1. Normal Class (25) Barite Type 2. Hemimorphic Class (26) Calamine Type 3. Sphenoidal Class (27) Epsomite Type Mathematical Relations of the Orthorhombic System Crystallographic Axes. - The orthmhombic system includes all the forms which are referred to three axes at right angles to each other, all of different lengths. 296 Any one of the three axes may be taken as the vertical axis, c. Of the two horizontal axes the longer is always taken as the b or macro-axis * and when orientated is parallel to the observer. The a or brachy-axis is the shorter of the two horizontal axes and is perpendicular to the observer. The length of the b axis is taken as unity and the lengths of the other axes are expressed in terms of it. The axial ratio for barite, for instance, is a : b : c = 0'815 : 10 : 131. Fig. 296 shows the crystallographic axes for barite.

Jan 1, 1922

By PW Meisel

An hydraulic-powered reel system to minimize peak tension transients in shuttle car trailing cables has been theoretically designed and analyzed using a computer. A single spring-loaded take-up sheave stores or gives up cable to maintain tension within specified limits. Controls have been incorporated to shut down the vehicle before all cable is removed from the reel and to de-energize the cable in the event of a reel/cable jam. Full-scale hardware configuration drawings sufficient for manufacture of a test system have been completed.

Jan 1, 1983

By D. Grgic, A. Giraud, F. Homand

RESUME : Le comportement mécanique partiellement saturé du minerai de fer a été étudié à partir d’essais de compression simple sur des éprouvettes à pression capillaire imposée par les solutions salines. Les échantillons restent peu saturés (32 %) même pour une humidité relative de 94 %, du fait de la présence de mésopores. Jusqu’à 90 % d’humidité relative la résistance diminue régulièrement. De 90 % à 94 % une forte chute est observée et pourrait être liée à la fois aux effets capillaires et à l’hydratation de certains minéraux. Le cycle hydrique subit par la roche dans la mine a été modélisé en 1D à l’aide d’un code de calcul entièrement couplé pour les milieux poreux partiellement saturés. Les calculs ont montré notamment une diminution importante en paroi des contraintes totales au cours de la phase de désaturation et une augmentation importante au cours de la phase de resaturation. Ces variations pourraient induire un endommagement du massif et être à l’origine d’instabilités, et soulignent l’intérêt d’une modélisation avec une géométrie plus adaptée. MOTS-CLEFS : mines de fer, partiellement saturé, pression capillaire, résistance, modélisation. ABSTRACT : The partially saturated mechanical behavior of iron ore has been studied from uniaxial compression tests on samples in which the suction is imposed with aqueous solutions. Samples are little saturated (32 %) even for a 94 % relative humidity because pores are too large. Up to 90 % relative humidity the strength decreases regularly. From 90 % to 94 % a great decrease is observed ; it could be explained by the capillary effects and the moisturizing of some minerals. The hydrous cycle imposed to the rocks in the mine has been modeled with an 1D fully coupled code for partially saturated porous media. The computations have shown an important decrease in the total stresses at the wall during the desaturation stage and an important increase during the re-saturation stage. These variations could induce a rock mass damage and instabilities, and highlight the necessity of a modeling with a well-adapted geometry. KEY-WORDS : iron mines, partially saturated, suction, strength, modeling. ZUSAMMENFASSUNG : Das mechanische Verhalten von teilweise gesättigten Eisenerz wird durch einachsige Druckversuche untergesucht. Die Prüfkörper haben einen durch Salzlösungen gestimmten kapillarischen Druck. Sie bleiben kaum gesättigt (32 %), sogar bei einer relativen Feuchtigkeit von 94 %, aufgrund der Anwesenheit von Mesoporen. Bis eine relative Feuchtigkeit von 90 % verringert sich gleichmässig die Druckfestigkeit und zwischen 90 % und 94 % merkt man eine starke Abnahme in Verbindung, möglicherweise, mit kapillarischen Effekten und Hydratation von bestimmten Mineralen. Die nümerische 1D Modellisierung des gezwungenen Wasserzyklus im Stein der Mine ist mit einem für porösen Medien ganz vernetzten Rechnungcode geführt. Sie zeigt besonders ein bedeutendes Sinken der Gesamtspannung während der Entwässerung und eine bedeutende Steigerung während der Sättigung. Diese Veränderungen könnten die Beschädigung des Gesteines herbeiführen und die Grundlage von Unstabilität sein. Sie unterstreichen die Wichtigkeit eine Modellisierung mit einer gut geeigneten Geometrie. STICHWÖRTER : Eisenminen, teilweise gesättigt, kapillarischer Druck, Druckfestigkeit, Modellisierung.

Jan 1, 2003

By Slobodan Radosavljevic

The polymetallic W-Pb-Bi-Ag ore from the ?Nova jama? ore zone of the Rudnik ore field have been investigated. Contact-pneumatolytic (skarn), pneumatolytic-hydrothermal, and hydrothermal mineralization phases are defined in this ore zone. The most significant mineralization phase that gave compact ore bodies is pneumatolytic-hydrothermal phase. A relatively pure Mo-free scheelite is the only tungsten-bearing mineral. Lead minerals are mostly presented by Pb-Bi sulphosalts and much less with galena. The image analysis coupled with Energy Dispersive Spectrometry (EDS) analysis on a Scanning Electron Microscope (SEM) was applied to the characterization of a W-Pb-Bi-Ag ore as an efficient tool for mineral quantification. Results of EDS (Energy Dispersive Spectrometry) analyses gave the empirical formulae: Pb1.91Ag0.05Cu0.08Bi1.93S5 for cosalite, Pb0.98Ag0.03Cu0.05Bi1.99S4 for galenobismutite and galena Pb0.99Ag0.03S.

Jan 1, 2006

By Rachel Bernau

Water wells, aquifers, and pipelines rarely incur damage from nearby blast vibrations. Extensive ground vibrations may cause a drop in the water table thereby changing an aquifer’s structure or drying up a well. Studies on the reactions of aquifers and water wells have been performed in Montana, North Dakota, and the Appalachia Coal Region. All of these studies reported that vibrations did not change the properties of the monitored aquifers and water wells. Rather, evidence suggests that any incurred damage was caused by block motion and downsloping.

Jan 1, 2001

By E. D. Palmes

This report was prepared by New York University Medical Center, Institute of Environmental Medicine, 550 First Avenue, New York, New York under USBM Grant Number G0133066, Personal Samplers for CO, NO and NO2 in Air. The grant was initiated under the Coal Mine Health and Safety Program. It was administered under the technical direction of the Pittsburgh Mining and Safety Research Center with Dr. George H. Schnakenberg acting as the Technical Project Officer. Mr. L. Young was the contract administrator for the Bureau of Mines. This report is a summary of the work recently completed as part of this grant during the period 3/1/73 to 11/30/76. This report was submitted by the authors in March, 1977.

Jan 1, 1977

By G. Atesok

Turkey?s EU affairs started in 1963 with the Ankara Treaty. On 31 December 1995 the Customs Union between Turkey and the European Union came into effect. In order to achieve the Copenhagen Criteria?s, Turkey, made laws parallel to the Framework Programs. On 3 October 2005, with the confirmation of ?Membership Framework Document? the negotiation process of Turkey has started. Coal had important role in the industrialization of EU and it is directly related to Energy and Environmental subjects. In this point many restriction became with the some protocols, in last decades. European Union composed Energy and Coal Policy, therefore engaged to reduce the emissions, and made new regulations. This regulations concern Turkey?s energy future, since large; but low quality of lignite reserves of Turkey, it is expected to have some difficulties with Union?s Environmental Legislation during Turkey?s congruity process. With the last natural gas import agreements of Turkey, the production and consumption of coal sunk in last seven years. However, considering environmental sustainability, the role of coal in energy production will rise up in the coming future. In this paper, in terms of Turkey Energy Sector, production and consumption problems of coal discussed and evaluated considering EU?s coal, energy and environmental rudiments.

Jan 1, 2014

By Grafton Thrasher

For the proper discussion of this subject it is necessary to incorporate in this paper the substance of part of an article published by rite in Metallurgical and Chemical Engineering for January, 1915. CAST-IRON TEST PLUG, SHOWING LOW MOTTLED AND MOTTLED FRACTURES. Several years ago, while I was thief chemist for a malleable-iron company, it occurred to me that the mere regulation of silicon was not sufficient to produce the desired degree of chill. But only after repeatedly encountering this fact in befit open-hearth and air-furnace, as well as cupola metal, was I led to regard variation in the total carbon as the principal cause of disturbance; and I resolved to determine the total carbon as well as the sill on ill every heat, and by a carefully prepared test piece to gauge the approximate degree of chill. The test piece selected was a round plug, 2 in. in diameter and 12 in. long, cast on end

Jan 10, 1915

By Launa G. Mallett, Jr. Brnich

Overview: The first step to emergency preparedness and maintaining a safe workplace is defining and analyzing hazards. Although all hazards should be addressed, resource limitations usually do not allow this to happen at one time. Risk assessment can be used to establish priorities so that the most dangerous situations are addressed first and those least likely to occur and least likely to cause major problems can be considered later. Purpose: This training package was developed to assist instructors as they (1) determine how to use risk assessment to improve safety preparedness and (2) present risk assessment concepts and tools to trainees. The concepts and tools presented here can be applied to any mine hazard.

Jul 1, 2003

By Kyle W. Charlton

The Bureau of Mines utilizes special testing methods for the analysis of underground mine atmospheres for use during or after mine disasters and fires. These methods depend upon drawing sample gas to the surface through multiple tube bundles with the subsequent analysis of grab samples or the automatic analysis by often remotely located instruments on a continuous, 24-hour basis. During cold weather, low ambient temperature causes condensation and freezing of condensable vapors in the sample which can result in delayed response times or complete blockage of the sample line. This report covers research and resulting development conducted by the Bureau of Mines to produce a reliable method to selectively remove condensable vapors and particulate in the sample gas stream under worst-case field conditions. The effort resulted in two prototype systems which have greater field utility than originally anticipated. The innovative project resulted in two patent applications submitted through the Bureau of Mines.

Jan 1, 1981

By Corate L. Brierley

Low-grade porphyry copper ores containing chalcopyrite as the primary mineral was leached by two strains of acidophilic, thermophilic microbes belonging to the genus Sulfolobus. Leach tests were conducted in glass columns heated to 60-70° C. Pinto Valley and San Manuel ores sized to -1/2 inch + 50 mesh were effectively leached by the thermophilic organisms, but pinto Valley and Cyprus Bagdad ores sized to -2 inch + 1/2 inch resisted leaching. Aeration did not contribute measurably to bacterial copper extraction, since two columns, one inoculated and one sterilized, having a rest/ leach cycle without recurrent aeration exhibited copper extraction patterns similar to those of the aerated columns. Distilled water can be substituted for 9K medium without diminishing copper extraction. Decreasing the pH of the leachate to about 1.8 enhanced the extraction of copper from pinto Valley ore with the thermophilic microbes. Thiobacillus ferrooxidans was found to be relatively ineffective at copper extraction from pinto Valley ore. Of eleven solvent extraction reagents tested, Adogen 364 and Warsol at concentrations of 0.1% and 0.012 were inhibitory to oxygen uptake by the two Sulfolobus strains. Di-2-ethyhexyl phosphoric acid at concentrations of 0.1%, 0.01% and 0.001% were totally inhibitory to the respiration of both organisms.

Jan 1, 1979