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Laboratory flotation tests on sized fractions of a certain number of selected minerals with homologous fatty acid derivatives (i.e. sodium salts and amine acetates) confirm that the higher homologues are more efficient collectors than the lower. Tests were carried out on sized material and finer size fractions floated at lower collector concentrations.It is suggested that selective flotation is best achieved with the reagent which most readily floats the most friable mineral in the ore, and that grade of product will be improved with the lowest usable homologue.INTRODUCTIONFlotation of non-sulphide minerals with fatty acids as collectors is usually less selective than the flotation of sulphide minerals with xanthate collectors. It is common to use the gradation in collecting power of homologous series of xanthates, as well as the more specific effects of activators and depressants, to achieve the separation of sulphides.The original aim of the work was to ascertain whether sodium salts of fatty acids (anionic) and fatty amine aceta:tes (cationic) could be selected from a homologous series to achieve better selectivity in separation of nonsulphide minerals by flotation. Subsequently the importance of friability of minerals in selective flotation was observed and the aim was expanded to develop a more practical approach to the testing of ore.MATERIALS USEDMineralsA series of massive mineral specimens, as pure as could be obtained, was procured. The specimens were cleaned by removing extraneous material, and then crushed and dry...

Jan 1, 1965

By Donald W. Gentry

This section deals with one of the most fascinating aspects of mining the evaluation of mine investment opportunities. Be-fore proceeding further, it is important to clarify the meaning of some fundamental terms used frequently in the text. 6.0.1.1 Mine Valuation vs. Evaluation The words "valuation" and "evaluation" in a mining context are often used interchangeably. However, for the purposes of this section, a distinction is made between the two terms in accordance with commonly accepted practice. The word valuation in a mining project context has the rather narrow meaning of placing a dollar or other currency value on the worth of the project as a whole. In other words, the value of a mining project refers to a measure of the desirability of ownership of that property. As such, the major item of interest is, "what is the mine worth?," or `what is the value of the mine?" The value of a mining project may actually be determined in the marketplace at any specific point in time, or it may be estimated by one of several methods. The topic of mine valuation is discussed in more detail in Chapter 6.1. The word evaluation in a mining project context connotes the broader meaning of determining the numerical values of all

Jan 1, 2008

The early history of the mine is traced from the beginning of shaft sinking in 1886 to the purchase by the Broken Hill Proprietary Co. Ltd. in 1949. A necessary preliminary to mechanisation of the Borehole Seam was development of the Young Wallsend seam, andthis development is described. Surface reorganisation and coal handling arrangements are dealt with in detail. Then follows a description of the Borehole Seam mechanisation, the provision of power supply for this purpose, arid pumping arrangements in themine.INTRODUCTIONStockton Borehole Colliery is in the Parish of Teralba, between the townships of Teralba and Boolaroo, and about 12 miles from Newcastle. The colliery holding, a freehofd area of 2,560 acres, was apparently an original land grant when acquired by Teralba Co-operative Coal Company who decided to mine for coal and named the mine "Teralba Colliery." Shaft sinking was commenced in 1886 but was delayed by financial and water troubles to such an extent that it was not until 1901 that the Borehole Seam was reached.Coal was won until 1904 using a single 16 ft. diameter shaft, ventilation being achieved by means of a wooden boxing down one side of the shaft. This collapsed, and operations ceased until the mine was taken over in 1906 by a company known as "Borehole Colliery Limited," the principal stockholder being the Stockton Coal Company. It renamed the mine "Borehole Colliery." This new company immediately commenced sinking a 13 ft. diameter air shaft. In 1908 the Stocktol1 Colliery at Stockton was abandoned, and during the following year much of its equipment was transferred to Borehole Colliery. The name was again changed becoming "Stockton Borehole Colliery." From this period on, coal was produced from the Borehole Seam by...

Jan 1, 1957

By D. R. Hack

The complexity of commercial mining software has gained rapidly over the past decade as hardware developments have surpassed software capabilities at a staggering rate. Software users, recognizing the limitations of off-the-shelf applications, have adapted embedded scripting languages. Custom programming has always had a vital role in mine computing innovations, yielding a dynamic research environment in industry and academia. Fields such as industrial minerals can benefit from customization of existing software, since the majority of mine planning software was designed for large metal mines. Different customization approaches utilizing embedded scripting languages are presented, with examples of sand and gravel applications in development. Following implementation by Surpac and development of the Surpac Command Language, Tcl has been widely applied. Mintec introduced Python, also extensible and portable amongst various operating systems, for use in their MineSight products. In early 2000, Gemcom introduced the use of Microsoft Visual Basic for Applications, widely used customization tools for a decade. Datamine implemented a flexible multi-language approach, with all program commands and processes available through the COM Server Interface. This extends customization from the existing macro language to scripting in HTML, JavaScript, or any language that supports COM.

Jan 1, 2003

By T. P. Williams, M. B. Rydzewski, B. Corner

Konkola Copper Mines (KCM) plc is an integrated copper producer operating on the Copperbelt in Zambia. KCM has numerous mining operations located in the towns of Chililabombwe (Konkola Mine), Chingola (Nchanga Open Pit and Underground operations), Lusaka (Nampundwe Mine), with a smelter located in Kitwe (Nkana Smelter) and an SX-EW plant in Chingola (Nchanga Tailings Leach Plant). [ ]

Jan 1, 2005

By L. Frederick

Measurement of gamma radiation occurring in nature to characterize geological formations has been widely recognized in mineral exploration. Different methods and apparatuses have been developed for drill hole logging purposes. Geological formations vary in amount of naturally emitted gamma radiation. A gamma signature from a geological formation is captured by utilizing different types of gamma detectors. A natural gamma radiation detector (NGRD) can be used to control mining whenever there is a significant difference between the radiation levels in the mineral or ore being mined and the waste materials surrounding the ore. Surface miners, such as the one shown in Figure 1, can precisely control the elevation of the cutter as the machine moves over the surface of the formation. This type of machine is predominantly used in selective mining operations, e.g. surface coal mining. If there is a means to know the position of the cutter relative to the interface between the ore and waste, the miner can recover all or most all of the valuable mineral with very little out-of-seam dilution. This paper discusses the results of a successful application of gamma detectors to control a surface miner at one of North American Coal Corporations? locations - Red Hills Mine. The mine has nine coal seams in total with thicknesses ranging from 12? to 60?. The bottom six seams (Figure 2) are minable. The mine has complex geology and a significant amount of annual rainfall (4.7 ft). The mine produces approximately 3.5 million tons of coal and about 40 bcy of overburden per year. The operation utilizes diverse mining equipment including Dragline Marion 8200, electric shovel P&H 2800, Caterpillar end dump trucks CAT 785 and 789; bulldozers CAT D11, D10, D8, and D6. Coal is mainly extracted by utilizing a Wirtgen SM 4200 surface miner that is loading CAT 785 trucks with high volume coal bodies and payload of 150 t. Operational cutting depth is 24 inches with maximum cutting depth of 36 inches. Surface miner operators determine a cutting depth based on multiple cues, the most important being visual observations of a coal seam being cleaned or mined. The cleaning process involves removal of the last foot of waste material covering the coal seam. This is one of two critical phases in the coal extraction process. If, during the cleaning process, an operator sets a cutting head too deep, valuable product is wasted. If it is set too shallow, waste material is left to be mined with the coal. The second critical phase occurs in the last cut on the interface between the coal and waste material at the bottom of the coal seam. If the cutting head goes deeper than favorable, then waste material is delivered to a power plant.

Feb 27, 2013

Jan 1, 1882

By A. Choudhury

Deep open-pit mines are becoming increasingly common in the highly mineralized arctic and sub-arctic regions. Air inversion is a frequent occurrence in these regions, and is exacerbated by the natural topography of an open-pit mine. Due to such inversions, the air quality in open-pit mines deteriorates very rapidly. Transport of gaseous pollutants under arctic air inversion is complex and involves an interaction between flow, thermal and convective transport systems. This paper discusses the construction and validation of a three-dimensional model that simulate the flow of air and the transport of gaseous contaminants in an arctic open-pit mine and the effect of low influent velocity and large gust velocities on the contaminants profiles in the mine. It was found that while higher velocities may remove contaminants from the pit bottom, they may not remove the contaminants from the pit entirely, necessitating artificial mitigation measures.

Jan 1, 2012

By Virginia T. McLemore

The Gallinas Mountains are in northern Lincoln County and southern Torrance County, New Mexico, USA where a series of alkaline igneous bodies, including porphyritic latite, trachyte/syenite, andesite, and rhyolite laccoliths, flows, dikes, and plugs, have intruded Permian sedimentary rocks belonging to the Permian Abo, Yeso, and Glorieta Formations. A small amount of bastnaesite, a REE mineral, was recovered during processing for fluorite from the Gallinas Mountains. Four types of deposits are found in the Gallinas Mountains: epithermal REE-F veins, Cu-REE-F veins, REE-F breccia pipes and iron skarn deposits; all are associated with Tertiary alkaline to alkalic-calcic igneous rocks. Alteration includes brecciation, silicification, chloritization, and fenitization. District zonation is defined by Cu-REE-F (±Pb, Zn, Ag) veins that form center of the district, surrounded by REE-F veins. Carbonatites are inferred at depth by the presence of fenitization, carbonatization of the breccias, presence of REE and similarity of the intrusive rocks and mineralization to areas with known carbonatites.

May 1, 2011

By Bernard Lewis

This report summarizes fundamental research end technical studies conducted in the Explosives and Physical Sciences Division, Region VIII, of the Bureau of Mines in the 2 years July l, 1950, to June 30, 1952. It is the fifteenth of a series of, ordinarily, annual reports whose aim has been to provide the reader with a resume of the research results that have appeared in published form during each fiscal year under the authorship of members of the staff. These are referred to throughout the report. ACKNOWLEDGMENTS Acknowledgments art, made to the following members of the Division wider whose mediate supervision the described studies were carried out. Stuart R. Brinkley, Jr., chief, Mathematical and Theoretical Physics Section, and special assistant to the chief of the division.

Jan 1, 1953

By Esteban Chumpitaz, Miguel Pacoticona, Ricardo Huancaya

El sistema cuenta con una alarma audible dentro de la cabina del camión que alerta al conductor en caso que el sistema detecte una condición de somnolencia. La información es almacenada en la base de datos y explotada gracias a los reportes que el sistema brinda, dichos reportes permiten identificar cuáles son los horarios en los cuales se da mayor incidencia de somnolencia, así como el récord por operador y por empresa. La instalación del sistema ha resultado bastante sencilla debido a que los componentes se concentran en un solo dispositivo que es la cámara Kinect, esta cámara consolida diferentes sensores en un solo dispositivo permitiendo su fácil instalación y adaptación por parte del operador. La implementación del presente sistema mantiene una excelente relación costo beneficio, ya que la inversión a realizar es mínima y el beneficio que se obtiene es bastante importante.

Sep 1, 2017

By Deepak Vidyarthi

This paper deals with the significance of Explosive Energy in the optimization of blast design parameters, and the benefits emerging out of it. It is based on the original work done by the author in developing and successfully implementing a site-specific software package on ‘Blast Design Optimization’ at Kudremukh Iron Ore Mine in India with a production level of 22.5 million tonnes of crude ore and off-take of Explosives of approximately 5500 tonnes per annum. The software package has yielded tangible results in effecting reduction in Explosive Consumption, substantial savings in the Cost of Explosive, besides Environmental Improvements by way of attenuation of Blast Induced Ground Vibrations as well as Air-Blasts. By carrying out regular ‘Regression Analysis’, and determination of the Rock Constants, it has been possible to further develop software packages as well as prediction curves for prediction of Peak Particle Velocity, Safe Charge of Explosive, Air-Blasts etc. A model has also been developed for the prediction of ‘Fly Rock’ although at KIOCL, fly rock does not pose any problem.

Jan 1, 2006

By Erich K. Bender

This report summarizes work performed under Phase I of USBM Contract No. H0366024, Noise Reduction of Jumbo Mounted Percussive Drills. Four drills -Gardner-Denver D93LAR and DH123 and Ingersoll-Rand 0475 and VL120 models were measured at the two manufacturers? test sites; data are given in terms of characteristic noise and vibration levels. A survey of percussive rock drill users is reported. The rationale for the choice of a demonstration drill, the Gardner-Denver DH123, is given and a desired noise reduction goal is established.

Jan 1, 1976

By Grey CA

Any economic evaluation of a lead-zinc mining project requires the estimation of net revenue per tonne of concentrate at the "mine gate". The value at the mine gate equals the Net Smelter Return minus all realisation costs. The paper develops a simple predictive model for Net Smelter Return based on metal prices.

Jan 1, 1990

By James C. Conti

A surface charge sensor has been developed that responds to changes in the double layer properties of colloidal silica during the cationic flotation of silica from taconite ores. Sensor design allows for the measurement of two aspects of the electrical double layer surrounding all solids immersed in ionic solutions. One aspect responds to a flow induced change in the double layer properties of a solid. The other is a function of the chemical composition of the aqueous phase. Evaluation of sensor performance during froth flotation experiments has been encouraging. Process monitoring capabilities are indicated.

Jan 1, 1981

During the extensive research which has been conducted in the Metallurgy Department of the University of Melbourne, into the properties of lead and its dilute alloys, the Brinell test has been used for the determination of hardness.The work described herein represents part of an investigation into the influence of various factors on such determinations, particularly when carried out on different qualities of "pure" lead. It is intended to publish the more theoretical and controversial aspects of this research elsewhere.MATERIALS USED AND THEIR PREPARATION FOR TESTINGThe tests to be reported have been conducted on a specially pure electrolytic lead, and several brands of commercially "pure" lead. The analyses of the samples upon which most of the work has been carried out are given in Table 1.Note: Oxygen was not determined, but from the work of H. W. Worner, in the Rosenhain Memorial Laboratory, it appears probable that it was approximately 0-0003% in all samples.

Jan 1, 1940

By Eduardo Luiz Sales Marinho

A Fábrica de oxigênio da AMT produz gases O2 e N2, utilizados no processo de produção de aço. Neste processo de fracionamento de ar, existe um compressor de ar que é responsável pela captação do ar atmosférico. Este compressor é do tipo centrifugo de 4º estágios de compressão, fabricação Hitachi, e tem capacidades de vazão de 114.000 Nm³/h e pressão de descarga 5.4 Kg/cm². Em Novembro de 2012, foi realizada inspeção no compressor e identificado trincas nas pás do impelidor do 4º st e perda de espessura de parede das pás do impelidor do 3º st de compressão. Houve perda da confiabilidade de operação do equipamento, sendo necessária uma ação para correção do problema. Depois de identificado a causa raiz das trincas,foi decidida a compra de dois novos impelidores com modificações no material para aumentar a resistência à corrosão. Na aquisição dos novos impelidores havia duas possibilidades: 1) Adquirir novos impelidores junto ao fabricante original do equipamento; 2) Adquirir novos impelidores por processo de engenharia reversa (levantamento de desenhos da peça desgastada para fabricação de uma nova) em conjunto junto com empresa especializada. Este trabalho irá mostrar os critérios e considerações que levaram a AMT decidir pela compra de novos impelidores por “Engenharia Reversa”, bem como, suas vantagens e riscos assumidos.

Sep 25, 2017

By Dhyemila de Paula Mantovani

Hoje em dia, a necessidade de utilizar materiais ecologicamente corretos tem aumentando em paralelo com a constante busca de novas tecnologias para produzir materiais renováveis, economicamente viáveis e tecnologicamente avançados, o que justifica esse trabalho. O presente trabalho consiste em estudar o comportamento mecânico de compósitos de matriz poliéster reforçados com fibras de cânhamo e testadas com impacto Izod. Para a realização deste teste, foram feitas amostras com dimensões de 10 mm de largura, 63 mm de comprimento e 12,7 mm de espessura em diferentes frações volumétricas de fibra, 0%, 10%, 20% e 30%. As amostras foram testadas em um conjunto pendular PANTEC na configuração Izod, modelo XC-50 localizado no LAMAV/UENF. A energia de impacto Izod dos compósitos de poliéster de 30% de fibras de cânhamo foi de 169,4 J/m.

Oct 30, 2017

By Carlos León Aguilar

Como una acción destinada a mejorar las condiciones de productividad de la compañía, Southern Perú desarrolló un programa conjunto de expansión de sus operaciones mina–concentradora tales como la marcha, evaluación y optimización de los circuitos de molienda, flotación, filtración y espesamiento. De acuerdo a este proyecto de extensión, los resultados metalúrgicos de la planta, recuperación y grado de concentrado posteriores a la expansión, son mejores que los estándares que manejaba la Concentradora previos a la expansión. Esto significa que los esfuerzos realizados para obtener mejoras constantes en productividad y calidad tuvieron resultados positivos. En ese sentido, el presente trabajo describe el proceso de ampliación de la compañía minera que conlleva una optimización en sus parámetros operativos como en el criterio ambiental, de forma que se permita optimizar la productividad y reducir los costos específicos de producción constantemente.

Jul 31, 2003

By Alfonso Rizo-Patrón Remy

El objetivo del siguiente trabajo es señalar un método que permita la recuperación económica de metales preciosos como el oro, plata y otros metales básicos (tales como plomo y cobre) de sus respectivas menas naturales y de los concentrados o relaves que los contengan. Para ello, se utlizará dos formas de aplicación: La primera se da en el tratamiento por cianuración de las menas, donde el carbón mineral es el medio precipitante de los metales disueltos. Mientras que la segunda ocurre cuando el carbón ha sido separado de las pulpas cianuradas, conviertiéndose en un agente reductor de los metales de fundición. De forma tal que se logra una recuperación integral de los metales preciosos y básicos en las barras de fundición.

Jun 20, 1954