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By Edmund Newton

The Haile mine has been the outstanding gold-mining operation and the largest single producer of gold in the Appalachian region. Gold was discovered at the Haile in 1827, previous to the present operation, production has been nearly $4,500,000 (gold at $20.67 per ounce.) from somewhat over a million tons of ore, with an average extraction of about 70 percent. The Haile property, now operated by Haile Gold Mines, Inc., is in the southern part of Lancaster County, South Carolina, 3-1/2 miles northeast of the town of Kershaw and 55 miles north of Columbia, the State capital. (See fig. 1.) The corporation has a lease and purchase contract on 1,805 acres, covering the present productive area. In addition, it holds lease contracts on 1,500 acres additional adjacent to this area.

Jan 1, 1940

By Juan Ayza

Dado que la geología económica estudia las materias del reino mineral que el individuo extrae para sus necesidades vitales, el presente texto señala la relación de ciertos minerales (estaño, tunsgteno, antimonio, manganeso, oro, plata, cobre, zinc) de la zona minera sur del Perú, con la geología regional y sus contribuciones económicas a través de personalidades como Balta, Steinmann, Dueffas, Douglas, Bulman, G. Peteraen, Newell, Heim; Newell, Chronic y Roberts; Jenka, Ahlfeld y Bruggen. De acuerdo a este estudio geológico se infiere que tanto el oro y el hierro pertenecen a la costa, así como los yacimientos de plata, plomo y zinc son de la cordillera volcánica, la línea de tungsteno de Cabanillas se encuentra asociada a granitos, los depósitos telegramáticos de cobre, antimonio, mercurio y plata, se encuentran relacionados a líneas tectónicas en la depresión del Titicaca. Asimismo en el yacimiento oriental, tenemos el peri y apomagmáticos de calcopirita, plomo-zinc, plata, plomo-plata, antimonio, oro, tungsteno y estaño. Finalmente, la repartición de zonas mineralizadas responde a dos causas: la asociación a varias clases de intrusiones y la relación directa a distintas categorías de líneas y regiones tectónicas.

Jul 20, 1956

By Wayne Burmeister, Danie Benade, Louis Meyer, Hugo Joubert

What is not measured cannot be managed. This is true of most things, including a furnace lining. This paper describes a Lining Management System used for this purpose. It provides the operations staff with a management tool to predict long term lining life and acts as a process optimisation tool. It alarms and records upset furnace conditions. Outputs from the system are described as presented through a specially developed software package and interface. It includes vertical and horizontal furnace sections showing estimated isotherms through the lining as well as the furnace bath. It also shows calculated heat flux values, estimated lining wear and the freeze layer profile. A novel three-dimensional display is described which provides the operator with a big picture view of the furnace crucible profile under real time operating conditions. The powerful trending facility for analysing both measured and calculated values is discussed. The required instrumentation hardware as well as the installation thereof is described, with special reference to an electrically insulating thermocouple socket design. Finally feedback is provided on the first year?s performance of the system installed on an open ferrochrome furnace at Assmang Chrome, Machadodorp, South Africa.

Jan 1, 2007

By S. A. Aye

Vibration levels on a variety of equipment in a South African opencast mine were measured in this study. The well-established ISO 2631-1 (1997) standard methodology was used for the computation of weighted root mean square (WRMS) and vibration dose value (VDV). This method was used to evaluate the whole-body vibration (WBV) on a wide range of equipment in the opencast mine using the two main parameters, namely the daily exposure A(8) which is based on the WRMS concept and the VDV which measures shocks. The results obtained show that while the majority of the equipment rendered exposure levels that are below the exposure limit value (ELV), exposure levels on about half of the equipment do exceed the exposure action levels. The study also highlights the importance of shock in the observed responses.

Jan 1, 2011

By Tian Sugui

By means of the measurement of the enduring property and microstructure observation, an investigation has been made into the influences of the element Re and TCP phase on the enduring property of the single crystal nickel base superalloys. Results show that the needle-like TCP phase is precipitated along the <110> orientation on {111} planes in Re-containing/free superalloys during the long term aging, the TCP phase is identified as µ phase, and the precipitated µ phase in 4.5%Re alloy is gradually spheroidized during aging. Thereinto, the needle-like µ phase may obviously decrease the enduring lifetimes of the alloys due to the consumption of the refractory elements and the effect of the stress concentration. But the stress concentration is not easily generated in the regions near the spherical-like µ phase, which is a main reason of reducing the enduring lifetime of 4.5%Re alloy to a small extent.

Jan 1, 2010

By R. Daignault et G. O. Allard

The Chibougamau area represents a part of the Abitibi greenstone belt. The rocks constitute a volcanic pile (Roy Group) overlain by a volcano-detritic sequence (Opemisca Group). Three important periods of tectonic deformation have been distinguished. The first one produced folds with north-south horizontal axes. The second one is responsible for the isoclinal east-west folds, and the associated regional schistosity. Reverse faulting contemporaneous with this period of deformation, produced two distincts effects. In some cases the faults cause a repetition of the stratigraphic sequence. Whereas in others the faults truncate second period folds. Domes and basins interference pattern are produced by the superposed effect of Di and D2 deformations. The motion of these two periods would be more or less contemporaneous. The deformation could be generated by rising diapirs of early plutons combined with the progressive formation of troughs by gravitational subsidence of denser strata. The rising diapirs of late granitoid plutons produces a wraparound of the host strata.

Jan 1, 1984

By Richard Addison

Rosario Dominicana, S. A. operates an 8,500 tonne per dayopen pit gold/silver mine in the Dominican Republic on the Caribbean island of Hispaniola. The mine is located in an agricultural area which is also an earthquake and heavy rainfall zone. In the 64 years from 1910 to 1974 there were 19 earthquakes within 300 km of the mine in the range of 6 to 8 on the Richter scale and the most recent earthquake in this range occurred in March, 1979. Average annual rainfall in the area is 1.7 m and is distributed throughout the year. Safe and environmentally sound tailings disposal in such conditIons has demanded the buiIding of an extremely strong dam wall and use of a fail-safe system of tailings disposal and solution reclaim. The type of dam, the system of tailings disposal and solution reclaim comprise an interesting example of the manner of handling tailings for a medium tonnage mine. The system is relatively costly but does assure a long-term, safe and trouble free structure and operating system. General views of the dam wall and tailings pond are shown in Figures l through 4.

Jan 1, 1980

By Bernhard Leist, William D. Leech, Johann Kröyer, Holger Evers

Landsvirkjun—the national electric power company of Iceland—is building the Kárahnjúkar Hydroelectric Project in eastern Iceland. Two glacial river systems will be dammed and channeled through a series of tunnels into a 690 MW underground powerhouse. The Project has a total of 73 km of tunnels to be excavated of which mosthave been completed. From three access adits, three large diameter (7.2 m to 7.6 m),main-beam, gripper-type, Tunnel Boring Machines (TBMs) are being used to complete50-km of the waterway tunnel. Using the TBMs was a first in Iceland to excavate the complex Icelandic basalt formations, which consist of inclined layers of hard basaltic flows with weaker scoriaceous and sedimentary interbeds. Faults, fissures and dykes that frequently cross the lava flows posed both geologic and hydrogeologic difficulties to the TBM tunneling. This paper describes the extreme challenges that the men and equipment had to endure to complete the tunneling, including the harsh winter weather on the surface and the cold, abundant ground water inflows within the tunnels.

Jan 1, 2007

By Miguel Calderón Rojas

"Quiruvilca, es una mina con sistema de mineralización de vetas angostas , donde el buzamiento de veta es variable entre 35° a 85°, y la calidad de roca es baja. En ese sentido, el presente trabajo describe el proceso de optimización del sostenimiento de las labores de minado (corona) a través del uso de pernos splits set y malla de acero electro soldada, en reemplazo de la madera. De forma que se genera mayor tiempo para elproceso de perforación y se determina labores que realizen voladuras masivas, mejorando la productividad y minimizando los ciclos de perforación y voladura."

Sep 14, 2009

The West Coast region of the South Island is situated astride the Pacific û Australian plate boundary zone. The most significant component of this zone is the Alpine Fault. A variety of reconstructions of the pre-Alpine Fault plate tectonic configuration of the New Zealand continental area have been attempted over the past 25 years or so. Most of these have not been closely constrained by a regional compilation of field data related to the age and horizontal displacement history of the Alpine Fault. A model in which the Alpine Fault was initiated no earlier than the interval 18 - 16.5 Ma (B.P.) is proposed, a significantly younger age of inception than has been widely accepted as the onset of dextral displacement along the plate boundary through the South Island. A subsequent history of displacement is presented consistent with the West Coast basin stratigraphy. The alluvial gold content of some parts of the Miocene to Pleistocene conglomerate sequences is also discussed.

Jan 1, 1996

By P. Rostami

It is important to study the ventilation system in order to better design and control of the working environment in deep underground mines. With increasing depth, heat, and humidity performance may be reduced and impair the attention of workers. The purpose of this paper is to apply a complex; development-end model configured in the MULTIFLUX program, developed at the University of Nevada, Reno, USA. The MULTIFLUX development-end model template has been benchmarked against measurement results from two UK coal mines in previous studies. The present study is a test of MULTIFLUX application in a metal mine. The model incorporates the simulation of the air flow field in the drift and the auxiliary air duct; simultaneous heat and humidity transport from the drift wall; heat and mass exchange between the air in the drift and the ducts; and the evaporation of process water and/or condensation of vapor as governed by the psychometric conditions. The results are compared with field data, measured at the Lucky Friday Mine (LF) in Idaho, USA, an underground mine and also shown between the results from the MULTIFLUX-based model, and those from another program, Kduct, developed at the Kyushu University in Japan.. Gao, K. Uchino & M. Inoue Fukuoka, Japan (2002)?

Jan 1, 2011

By R. K. Dunham, D. J. Reddish, X. L. Yao

Paper presented at the conference: Risk assessment in the extractive industries, held in Exeter, UK, 23-24 March 1994, and first published London: IMM, 1994, preprint volume, 10pp., 10 refs. The integrated approach combines a powerful ground movement prediction program with a knowledge-based expert system. ESDAS (Expert Structural Damage Assessment System) was developed to evaluate mining subsidence damage in the form of risk and in terms of the three vital contributing components (mining factors, site factors and structural factors). Using a certainty factor risk assessment technique, the system can be used to predict the likely damage to a particular structure subjected to mining subsidence. A previously developed powerful ground movement prediction program, SWIFT (Subsidence With Influence Function Techniques), has been combined with the expert system to allow the mining factor to be more accurately determined in a broader range of mining layout. Since SWIFT can be calibrated to any particular coal field using local subsidence data, it is believed that the integrated system could be used in any coal field worldwide for the assessment and control of mining subsidence damage risks

Dec 1, 1995

By D. Settles, R. Rose, P. L. Dunn

"A new mineral sands operation is being developed in Georgia by Southern Ionics, Inc. (SII). Prevailing mineralogy and certain design constraints required detailed testing and circuit analysis to create a robust separation processes. The floating wet concentrator plant (WCP) and mineral separation plant (MSP) flow sheets were designed based on historical testing information and recent SII test campaigns on various composite feed samples. The flow sheets were finalized through rigorous process and orebody sequence modeling.The process uses traditional physical separation equipment; however a new MT spiral, the MG12, was selected for use on board the WCP for roughing duty. The MG12 spiral is a two-stage, twelve-turn spiral that has been proven to achieve very high recoveries of heavy minerals. The floating plant includes feed desliming operations, a central MT surge bin for optimum spiral circuit feed control and ancillary operations for concentrate and tailings handling. Scrubbed heavy mineral concentrate (HMC) is then transported to the MSP for concentration of the titanium and zirconium bearing mineral fractions.The testing, flowsheet development, and plant design will be described and explained, and a brief summary of the current project status will be given.IntroductionSouthern Ionics Inc. (SII) is a privately held chemical manufacturing company, founded in 1980 by Milton Sundbeck. SII focuses primarily on the sale of specialty and intermediate inorganic chemicals. Core markets include cement and refinery catalysts, molecular sieves, zeolites, pulp and paper, pharmaceuticals, TiO2 and water treatment. SII is built on the four cornerstones of service, quality, technology and delivery with all SII facilities ISO certified and key products used in potable water treatment certified to NSF standards. SII owns and operates its own transportation fleet and is focused on being a low cost producer, committed to safety and the environment."

Jan 1, 2015

Inhibition of Bubble Coalescence by Salts and Sugars

Sep 13, 2010

By Pati±o A

The Argentine pyroclastic loess arevulcanogenic deposits, which have their sources in the circumnpacific rim. The object of this work is to realize a de-tailed mineralogical characterization of this sediments, to use it like a geo logic outline which regiters discordance or similarity in them, The sampling zone extend from 714N-4125 to 622W-339S. The descriptions of these sediments was considered like basic, mesobasic or acid rocks. The basic sediments, looking like andesite-basaltic composition, are fill-ing the andean valley. The mesobasic one have a similar composition with a pyro-clastic dacite rock, and have been found in marshy pleistocene sediments in the intermountain valley and in the pampeana prairies. The acid ashed conform rhyoda-cite-rhyolite sediments which form the pampeana loess covers in the prairie.

Jan 1, 1990

By G. T. Engel, W. G. Gruzensky

Jan 1, 1960

By Don Phelps, Dean Brox, Peter Procter, Andy Saltis, Tom Morrison, Jeff Pringle

The Greater Vancouver Water District is currently constructing the Seymour-Capilano Water Filtration Project to enhance the quality of drinking water in the Vancouver metropolitan area. The Seymour-Capilano Water Filtration Project comprises the 1,800 million litres per day Seymour-Capilano Filtration Plant, the 1,080million litres per day Capilano Pumping Station, twin tunnels with associated shafts, and the Capilano Energy Recovery Facility. The twin tunnels will convey raw water under pressure from the Capilano Reservoir to the Seymour Filtration Plant and return treated (filtered) water for distribution. The Twin Tunnels component of the project comprises twin, 3.7 m diameter, 7.2 km TBM bored tunnels, the 180 m deep Seymour Shaft as the main launch shaft, and two 4 m diameter, 268 m deep raise bore exit shafts at Capilano. The Twin Tunnels have been planned as predominantly unlined tunnels sited at depth entirely within granitic bedrock and cross under two major buried glacial valleys of breadths in excess of 1500 metres that are filled with glacial sediments to depths up to 200 metres. The maximum overburden along the tunnel alignment is approximately 400 metres. Comprehensive site investigations and studies were completed during the detailed design stage of the project. The construction of the twin tunnels started in the fall of 2004 and is planned to be completed by mid-2008.

Jan 1, 2005

Electrochemical measurements are presented on electro-deoxidation of silica in molten calcium chloride at 900°C, with porous silica pellets as starting material. Measurements during pre-electrolysis (to remove water from the melt) showed electrochemical noise, which is consistent with the evolution of hydrogen. Throughout, the dominant anodic reaction appears to be CO2formation, based on the observed potential at the anode, and measured anode wear. Because of the presence of dissolved CaO in the melt, some of the CO2 candissolve in the melt; the resulting calcium carbonate formation was confirmed by electrolyte analysis after reduction runs. Reduction of dissolved CO2 at the cathode is likely to contribute to the background current during the reduction process. For the electrode and cell configuration used here, most of the over potential arises from polarization of the anode, and ohmic potential drop in the electrolyte.

Jan 1, 2006

A pilot plant was constructed for the low temperature carbonization of Wallarah (N.S.W.) coal at the rate of 300 lb/hr. The design was based on an entrained state carbonizer developed by Parry and D.S. Bureau of Mines co-workers. Prior to delivery to the client, the plant was successfully operated over periods of several days duration.INTRODUCTIONIn September 1961, the Australian Mineral Development Laboratories (A.M.D.L.) was engaged by the Broken Hill Pty. Co. Ltd. (B.H.P.) to design, construct and test an entrained state coal carbonizer with a capacity of 300 lb/hr of Wallarah (N.S.W.) coal. Char product was required within the specification 15&#183;5 -I- 1 per cent volatile matter. The design was to be based on a pilot plant developed by Parry and others in the D.S. Bureau of Mines Coal Research Laboratory at Denver, D.S.A. The method involved the carbonization of fine coal by entrainment with air in an externally heated reactor. The heat required for the carbonization of the coal was to be supplied to the bed both through the reactor walls, and also by internal combustion of products in the bed. Several D.S. Bureau of Mines Reports of Investigations weFe used as the main guide to the physical layout and proportions of the plant. However, the individual units required detailed designing, before engineering drawings could be prepared and fabrication begun.A 10 ton sample of crushed Wallarah coal was used for preliminary testing of the plant. The first test run on the pilot plant was carried out in February, 1962. After some modification a second test of longer duration was conducted in August, 1962. These operations aimed at running in the plant and also at determining the operating temperature to produce specification char and the maximum capacity of the...

Jan 1, 1963

By Earl S. Greiner, Eric R. Jette

The constitution of the iron-silicon alloys containing from 14 to 33.4 weight per cent silicon has been studied by a number of investigators, whose results have been reviewed in a monograph published by the Engineering Foundation1. In these previous researches, the solubility of silicon in iron was determined by thermal, microscopic or magnetic methods and the compound Fe3Si2 was reported to be stable at temperatures from 0 to approximately 1030&apos; C. This paper describes the results of an X-ray investigation of the solubility of silicon in iron and gives data which prove that the Fe3Si2 phase is unstable below 825" C. In order to obtain the present results on the solubility of silicon in iron, the authors have utilized the lattice constants of the alpha-phase iron-silicon alloys given in a previous publication2, and also some additional data which will subsequently be described. Materials and Methods The alloys used in this investigation are listed in Table 1. They were prepared in 30 or 50-gram ingots by melting specially purified silicon and electrolytic or carbonyl iron in alundum crucibles under a pressure of less than 1 mm. of mercury. The purity of the silicon, electrolytic and carbonyl irons has been given by the authors in previous publications2, 5. The ingots were homogenized in vacuo at approximately 1000" C. for at least 96 hr. and then slowly cooled. The homogenized specimens were ground to powder in a hardened steel mortar. This powder was passed through a 150 or 200-mesh screen and sealed in evacuated quartz, Jena or Pyrex glass tubes and heat-treated as noted in the various tables. Specimens 23A, 24B, 33 and 35 and the specimens heated for one month at 700" C. were quenched by quickly removing the tubes from a horizontal tubular furnace and dropping them into water. The other specimens were quenched by means of a drop-quenching device, which has been described previously3.

Jan 1, 1937