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By Jr. Sillers

This is the third report of investigations dealing with the application of electrolytic manganese to steel-foundry practice and the seventh in a series of reports dealing with tests to establish the technological acceptability of electrolytic manganese in the iron and steel industries. The work was carried out by Metallurgical Division of the Bureau of Mines as part of an extensive program for the development and utilization of domestic ores. The electrolytic manganese used in the tests was produced by the Bureau at its Boulder, City, Nev., pilot plant by the process developed by the Bureau of Mines.

Jan 1, 1949

By Luis Wilson Arzapalo

El tema refiere a las acciones que llevara a cabo el equipo de operaciones, una vez terminado el "Comisionamiento" donde la Planta ha alcanzado el estado "Listo para Arrancar". En el periodo de puesta en marcha de una planta de proceso, se encuentra una serie de dificultades de índole operativo; saltan a luz las propiedades físicas y químicas del mineral no detectados durante las investigaciones metalúrgicas previas, se hacen presente los defectos de diseño de los equipos los cuales a su vez pueden estar sub o sobredimensionados y otras manifestaciones no esperadas. En tal virtud el conocimiento de los metalurgistas experimentados en este tema, las continuas prácticas de liderazgo participativo y la capacidad de decisión, deben hacer que los motores y equipos reciban la alimentación planeada y entreguen el producto esperado para garantizar el equilibrio del sistema.

Sep 21, 2015

By V. Galla

In the present paper, two large diameter columns 2 m tall and 1.3 m diameter filled with crushed (finer) and run off mine (coarser) heap leach materials respectively were used to perform unsaturated flow studies. Instruments measuring moisture content and matric suction were placed in the columns at different depths as water was applied at calibrated flow rates from the top of the columns. The outflows from the columns were recorded using tipping bucket rain gauge placed at the bottom of the columns. Unsaturated hydraulic parameters were also obtained for the heap leach materials, scalped (passing 4.75 mm sieve size) and whole (passing 37.5 mm sieve size) sample. The measurements obtained from the columns were later compared with unsaturated flow modeling results. The comparison indicated sensitivity towards the sample size selection for unsaturated hydraulic parameters, and initial conditions considered in the model.

Jan 1, 2009

By T. M. Ruff

A GPS-based traffic awareness and collision avoidance system has been implemented at mines with long, narrow access roads to help avoid accidents involving two approaching vehicles or vehicles following too close. A simple display in the cab of each outfitted vehicle gives an indication of oncoming traffic and a voice announcement indicates the type of vehicle that is coming as far out as 300 meters. Advanced warning of approaching vehicles is increasing driver awareness, especially around blind corners and in adverse weather such as heavy fog, snow, or rain. Speeding alarms have also been implemented and are especially critical as a vehicle approaches reduced speed areas near single-lane bridges or tight curves. A description of the system, safety improvements seen since its introduction, and implementation challenges will be discussed.

Aug 1, 2013

By John Dasher

The impetus given to mineral dressing arid chemical engineering by the war has placed many persons without previous experience in positions where they are concerned with the size of solid materials they are testing. Many good textbooks cover this field in considerable detail but are more concerned with the "why" than with the "how" For beginners and those to whom size is not of primary concern, this brief circular has been prepared. Refer-

Jan 1, 1942

By Jose M. S. Ramos

This paper describes the slope stabilization procedure at Cauê Mine, Companhia Vale do Rio Doce - CVRD, Itabira, State of Minas Gerais, Brazil. Cauê Mine, is a large open pit, to produce about 41 million tons of iron ore during 1974, and an intensive program of investiga Lion was carried out to provide the basic data for stabilizing its slopes, The ultimate rock slope in the W area will be about 400 m high with dipping angles decreasing gradually from top to bottom of the pit. The investigations started in 1969 and since then many geologists and engineers, from both CVRD and Geotécnica S/A., assisted by international consultants, have given their contribution to the achievement of solutions. It is hoped that this paper may contribute to the slope stability of other mines in tropical climate.

Jan 1, 1974

By J Cardozo

El presente texto señala las pruebas que comprenden el proceso de rehabilitación de la mina Pierina de tajo abierto. En esta perspectiva, las pruebas y monitoreos identificaron que los paneles cubiertos con el sistema de confinamiento geocelular Geoweb asociados a otros geosintéticos y a un tratamiento biológico de los suelos tienen buen rendimiento, generando vegetación y un comportamiento estable en los cinco años que tiene el proyecto.

Aug 1, 2013

PRESIDENT SAMUEL A TAYLOR, District 3 PITTSBURGH, PA PAST PRESIDENTS WILLIAM KELLY, District 5 IRON MOUNTAIN, MICH J V W. REYNDERS, District 0 NEW YORK, N Y FIRST VICE-PRESIDENT E DEGOLYER, NEW YORK, N Y TREASURER CHARLES F RAND. . . NEW YORK, N Y

Jan 1, 1923

By Paula Rodrigues Caumo

A tecnologia da fabricação de aços, nas últimas décadas, apresentou grandes avanços, os quais resultaram em melhorias da qualidade, principalmente no que se refere à remoção de inclusões. As inclusões podem ser responsáveis por prejudicar as propriedades mecânicas por meio da geração de trincas ou fraturas entre outros defeitos. O distribuidor do lingotamento contínuo também pode atuar na remoção destas partículas. A eficácia desta função do distribuidor demanda o conhecimento das características do escoamento do aço líquido de modo que se possa propor modificações na configuração do distribuidor. Esse conhecimento pode ser obtido mediante a utilização de modelos físicos para simular os fenômenos envolvidos. O objetivo deste trabalho é, a partir de um distribuidor com jato aberto, construído em acrílico e em escala 1:1, verificar o percentual de inclusões passantes pelo veio com ou sem a presença de bolhas. O trabalho foi executado com e sem tubo longo, sendo o tubo longo empregado para prevenir o arraste de ar para o interior do modelo. Os resultados foram obtidos por meio do ensaio de remoção de inclusões com o auxílio do ensaio de distribuição de tempos de residência. As variáveis utilizadas neste estudo são: presença bolhas e velocidade de lingotamento.

Aug 16, 2017

By R. Fuenzalida

Since 2007, a number of Multivariable Predictive Control (MPC) Applications have been implemented on SAG mills, among others, within the Kairos Mining Concentrator Automation Program using ?Profit Controller?? and other tools comprising the ?Profit Suite??. Along this journey, several interesting and challenging issues related to SAG mill operation and control have been faced, which are relevant to be shared with the Mineral Processing community. These advanced control applications have an operational objective whose goal is to increase marginal profit on the concentrator, together with increasing mill stability. In regard to this objective, the issues to be presented and described are in direct relationship with ?Profit Controller? features and the SAG role; they are also stated and linked to get the most of the mill. Some conclusions and findings are also presented, leading to recommended practices on how to use the controller. These findings have also lead us to decide further actions to be taken on new applications to deploy and also on devising and implementing some complementary components to increase robustness of the overall automation solution, as well as reducing the need for operator intervention.

Jan 1, 2012

By William H. Shockley

[SECRETARY'S ]NOTE.-The following notes, arranged and edited in this office, but not yet revised by the author, were placed at my disposal with much modest hesitation (due to their incomplete and fragmentary character), upon my earnest request, and my argument that such recent and trustworthy data concerning a new and important mining industry ought not to be withheld from our Transactions, simply because they are not sufficient to constitute a, complete academic treatise on the subject. This argument is recommended to the attention of many other members, who are waiting for the opportunity to contribute something "monumental" to our Transactions. In a number of instances, death has nulli¬fied this ambition, and the intended "monumental" contribution has turned out to be an obituary notice by the Secretary, instead of a valuable record of the professional experience thus hopelessly lost to the world.-R. W. R.] The official publications of the the Russian Government give fairly complete statistics of the dredges operated in the Empire; and in a recent English bluebook, Mr. Cook's report on Siberian Trade presents a brief account of dredging in Siberia. The data in Table I. (not given by Mr. Cook) have been taken from the Gold Mining Messenger (Russian) for July, 1905. These interesting statistics, though incomplete, show that the Yenisei dredges are working on poor ground and yield small returns. According to report, but few yield a profit exceeding 10 per cent. per annum on the capital invested. In the summers of 1904 and 1905, I traveled in the Urals as far north as lat. 61° N., long. 61° E., on the the Lozva river, a part of the vast system of the 01) river. This clear-water stream starts from the summits of the Urals at an altitude of 4,000 ft., and flows through a flat country, densely wooded with larch, spruce, pine, fir, birch and poplar. The river is full of fish, and is navigable for good-sized steamers as far as Ivdell. Winter lasts from early November to late April, the temperature rang¬ing from -60° F. to a summer maximum of 90° F. The rain¬fall is 20 in.. The climate is healthy, although mosquitoes,

Jul 1, 1906

By Luis Paretto Olivera

El objetivo del trabajo estriba en el desarrollo de un método práctico para la determinación del bióxido de nitrógeno a niveles de mayores niveles de concentración mayores, donde se utilize el reactivo de Saltzman especificado para el gas, elimine el problema de utilizar botellas o jeringas hipodérmicas, y se mejore los resultados productibles. El estudio fue complementado por comparaciones de concentración de bióxido de carbono determinadas con la jeringa hipodérmica y el burbujeador poroso y la relación de los mismos (técnica de muestreos, métodos de análisis,y estandarización).

Aug 20, 1963

By D N. Castendyk, J L. Mauk

The world-class Waihi (>6.6 Moz Au, >41.8 Moz Ag) and adjacent Favona (>0.5 Moz Au) deposits are within a single volcanic-hosted epithermal Au-Ag district located in the southern Coromandel Peninsula, New Zealand. Gold and silver mineralised quartz veins at both deposits are hosted in porphyritic andesite flows of the Waipupu Formation. Both deposits have veins surrounded by intense widespread hydrothermal alteration that is characterised by the assemblage of quartz, pyrite, adularia, illite or interstratified illite-smectite, plus less common chlorite and albite, which is locally overprinted by minor calcite or rare kaolinite. Quantitative mass transfer calculations using Gresen's general metasomatic equation indicate that hydrothermally altered andesite at both deposits is enriched in silicon, potassium, rubidium, barium, sulphur, gold, arsenic and antimony, whereas sodium, strontium and calcium are mostly lost. Iron and magnesium show mixed gain and loss. Element gain or loss can be directly related to the prevailing alteration mineralogy. Addition of potassium, rubidium and barium coupled with the concomitant loss of sodium, strontium and calcium in intensely altered wall rocks corresponds to the replacement of plagioclase by adularia or illite. Partial retention of sodium and calcium reflects the presence of hydrothermal albite and calcite, respectively. Mass balance calculations show distinct element gain and loss that can be related to the intensity and type of alteration mineralogy. However, because most rocks are intensely altered and the progression into less altered peripheral rocks is not observed in this study, the lateral extent of elements gain or loss is unconstrained with anomalies extending at least 200 to 300 m away from major veins.

Jan 1, 2003

By Enrique Monge

"El presente texto describe las funciones y objetivos del Instituto de Investigaciones de la Siderurgia (TRSI ). Dicho instituto fue creado en 1944 por el Comité de Organización de la Siderurgia de Francia e inició sus actividades en 1946. Su objetivo fundamental es efectuar investigaciones, tanto científicas como de aplicación industrial, sobre los problemas que afectan a la Siderurgia Francesa. Asimismo, este instituto dispone de un laboratorio de mineralogía en París para sus estudios minerales y de instalaciones en Thionville y Lonwy, para sus estudios sobre fundiciones y coque. "

Nov 1, 1960

By J P. Barkas

World demand for iron ore is far from peaking, and the substantial price decline that has captivated commentators since early 2014 is not the result of widespread misreading by producers of the prospects for global market growth. Recent price movements provide little useful insight into the industry’s longer-term fortunes, apart from reminding mining companies that their businesses need to be robust against the volatility and inescapable cyclicality of mineral commodity markets. It is timely to take a strategic view of the history and longer-term prospects for the iron ore industry and of Australia’s place in it.CITATION:Barkas, J P, 2015. Perspectives on the long-term outlook for iron ore, in Proceedings Iron Ore 2015, pp 3–6 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Jul 13, 2015

By W. Ellison

Worldwide development of commercial markets for FGD (flue gas desulfurization) gypsum is described and used as a basis for assessing potential overall market growth and regional demand foreseen in the U.S. during the 1990s. Diverse strategies are outlined for cost-effective substitution of this major supply from acid rain control retrofits (power plant scrubbers) for natural gypsum in the principal, existing markets: gypsum board and portland cement. Another focus of utilization forecasting is a key group of related. new-product advancements including floor screeds, mining mortars and various types of innovative construction products.

Jan 1, 1993

By Detlef Ehlert

With the proven “Plug & Work” concept developed by SMS Siemag, automation systems are tested and optimized in the test field in a near-reality environment before being shipped and commissioned at a customer’s site. The process and production simulations provide scenes showing the specific mechanical equipment, the drive systems and the technology of the corresponding customer plant. Beside the technological simulation of the plant and the IO-simulation with the automation system, the production simulation is one of the three important parts of the Plug & Work simulation environment. It serves two important additional purposes: the 3D visualization of the entire customer plant on the one hand and the mapping of the logistic procedures in the plant on the other. In order to provide a close-to-reality visualization of the plant, the original design data of the individual customer plant are used for creating the visualization and prepared using an appropriate export filter. In this way, it is ensured that production sequences can be optimized in advance together with the customer, so that each customer can be trained on his own future plant.

Aug 16, 2017

By Y. C. Kim

Using an exhaustive data set of Walker Lake, four different kriging techniques plus the inverse distance squared weighting were compared with regards to each one's performance in accurately estimating the block grades. The North-West quadrant of the Walker Lake data area was used because of its extreme variability of values and its distinct contour of the values. There were 1900 exhaustive data points in the selected area from which a total of 121 samples were drawn following the sampling strategy given in Isaaks and Srivastava (1989). The average of 5 x 5 exhaustive data points was treated as the true, known block grade. A total of 780 blocks, each block corresponding to the average of 5x5 exhaustive data points, were then estimated using the 121 sample points. The resulting estimates were then compared with the true known values to determine each technique's prediction performance. For this particular portion of the Walker Lake and for the given sampling strategies used, the obtained results for the global estimation are mixed. For the variable U which is much more variable, the rankings are; 1) Jackknife Kriging (JK), 2) Indicator Kriging (IK), 3) Inverse Distance Square weighting (IDS), 4) Ordinary Kriging (OK), and 5) Log-Jackknife Kriging (LJK). For the variable V, the results are; 1) OK, 2) IK, 3) JK, 4) LJK, and 5) IDS. When we apply several cutoff grades to the estimates to determine the conditional mean grades and tonnage, the above rankings generally get shifted around. Two exceptions to these cases are; a) UK for U and b) IDS for V. These two consistently ranked at the bottom.

Jan 1, 1995

By André Oliveira Galon, Elton Volkers do Espírito Santo, Caio Vaccari Silva, Victor Bridi Telles, Raphael Mariano de Souza

Para atender a demanda do mercado por aços com teores de fósforo cada vez menores, dominar os métodos desfosforantes mais eficientes é fundamental. Desse modo, o uso da termodinâmica computacional é extremamente importante, uma vez que as simulações vias softwares representam um caminho rápido, seguro e eficiente para se obter resultados no campo da aciaria. No presente trabalho foi proposto com uso do FactSage 7.2 a análise da eficiência de desfosforação de diferentes fluxantes: fluorita, sodalita, B2O3 e barrilha; que foram adicionados a uma mistura desfosforante padrão de 70g, nas simulações a massa total foi mantida constante em 70g e a porcentagem em peso usada dos fluxantes na mistura foi de 5 e 10%. Como tem-se em literatura que é possível correlacionar o fator de desfosforação (FDeP) com a eficiência, após o cálculo do FDeP feito através das simulações do FactSage, foi feita a correlação com a eficiência para se saber qual o fluxante era o mais eficiente e qual era o efeito do aumento da porcentagem em peso dos fluxantes na mistura desfosforante. A fluorita mostrou-se o fluxante mais eficiente seguido da barrilha, e a maior eficiência era atingida quando a porcentagem em peso dos fluxantes era de 5%.

Oct 1, 2019

By Allen Chung, John Twomey, Christopher J. Greet

"It is widely accepted that the type of grinding media has an impact on the grinding chemistry and subsequent flotation behaviour of the sulphide minerals being separated. There are countless laboratory investigations demonstrating that inert grinding media produces more oxidising pulp potentials, reduced levels of grinding media corrosion products and superior concentrate grades and valuable metal recoveries. However, taking these results to industrial scale has proven difficult.Work conducted at the Ernest Henry Mine, in north western Queensland, Australia, at laboratory and pilot plant scale clearly indicated that using a high chrome grinding media resulted in significant improvements in both copper and gold recoveries. However, advancing this work to plant trial represented considerable financial and technical risk to the mine.This paper provides details of the protocol developed and used during the high chrome grinding media plant trial. It describes the test regime employed to measure changes in pulp chemistry, and the statistical methodology utilised to interpret the results. The work also highlighted the need for close cooperation between the metallurgists on site and the researchers conducting the trial.To date, the trial has produced excellent results: indicating that the copper recovery has improved by about 2 percent. The successful application of high chrome grinding media to the Ernest Henry ore has increased metal value by $18.7 million USD per annum based on current spot price for copper.INTRODUCTIONTheoryThe application of electrochemically inert grinding media to mineral systems has been extensively studied (Table 1). Broadly, these studies indicate that most sulphide minerals are more noble than the grinding media used during comminution. Therefore, the sulphide minerals are cathodic with respect to the forged steel grinding media, and the following reactions apply:"

Jan 1, 2011