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By M Bird, B Oats, M Sganzerla

Mining operations are continually aiming to reduce operating costs to improve plant profitability. One way in which the Cannington operation sought to achieve this was by increasing the wear life and reducing the energy consumption of their flotation mechanisms. This was made possible using Outotec’s FloatForce mechanism. The FloatForce mechanism has been developed by Outotec over a six year period involving both CFD modelling and rigorous site testing. FloatForce delivers improved air dispersion and cell agitation efficiency; as such it can be operated at lower rotor tip speeds when compared to Outotec’s previous mechanism.Cannington trialled three FloatForce mechanisms in a train of ten OK38 zinc roughers. The mechanisms’ rotational speed was reduced by 10% compared to the previously installed MultiMix mechanisms. The purpose of the trial was to quantify the energy saving and assess whether there was any reduction in plant metallurgical performance.The trial was successful with FloatForce delivering a 17% reduction in power, an improvement in wear and improved recovery. Analysis of pre and post-installation metallurgical accounting data showed the following:The FloatForce installation resulted in a recovery increase of zinc to zinc final concentrate of 0.4 – 4.0%*The FloatForce installation resulted in a recovery increase of lead to zinc final concentrate of 0.0 – 0.3%*There was no statistically significant change in silver recovery to zinc final concentrate that can be attributed to FloatForce**95% confidence interval (CI) using multiple linear regression models.The Cannington operation is now in the process of further optimizing its power consumption and wear savings by changing the remaining OK38 zinc and lead rougher float cells to FloatForce mechanisms.CITATION:Bird, M, Oats, B and Sganzerla, M, 2015. Improvements in flotation cell maintenance, power consumption and operation at South32 Cannington, in Proceedings MetPlant 2015, pp 230–245 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Sep 7, 2015

By Gregg Davidson, Lonnie Jacobs, Brett Zernich, Alan Howard, Robert Pintabona

All Rights Reserved. Printed in the United States of America. Information contained in this work has been obtained by SME, Inc. from sources believed to be reliable. However, neither SME nor its authors guarantee the accuracy or completeness of any information published herein, and neither SME nor its authors shall be responsible for any errors, omissions, or damages arising out of use of this information. This work is published with the understanding that SME and its authors are supplying information but are not attempting to render engineering or other professional services. If such services are required, the assistance of an appropriate professional should be sought. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of the publisher. Any statement or views presented here are those of the authors and are not necessarily those of SME. The mention of trade names for commercial products does not imply the approval or endorsement of SME.

Dec 1, 2014

By Filipe Sathler

Mediante efeitos de sazonalidades do mercado Siderúrgico, períodos de crise, aliados às necessidades de reparos de equipamentos, os Altos Fornos são, eventualmente, submetidos ao desligamento. O procedimento específico mais utilizado é o Blowdown, com o abaixamento de carga até nível de ventaneiras, facilitando posterior limpeza e reparo. Para sucesso deste procedimento, é essencial um planejamento adequado das atividades. Informações técnicas e experiências operacionais permitiram o embasamento teórico e a execução do Blowdown do Alto Forno 03 da ArcelorMittal FCSA (Tubarão). Como preparação, foi efetuado o aumento do fluxo periférico (remoção de cascão) e o aumento da permeabilidade do Cadinho (maior circulação de líquidos, limpeza e drenagem). Realizou-se também a preparação de equipamentos específicos e controle dos parâmetros operacionais. O abaixamento de carga foi devidamente realizado conforme planejado, até o nível de ventaneiras e permitindo paredes internas livres de cascões.

Aug 16, 2017

By James Warner, Peggy Ganse, Glen Smoak, Raymond Henn, Sam Bandimere

Over the past several decades, cement-based grouts using ultrafine cement as are placement for portland cement have begun to gain acceptance as an alternative to chemical solution grouts, however the amount of information currently available on these grouts is limited. For this reason, the authors developed a field testing program to evaluate the penetration capabilities of various ultrafine cement grout mixes. The tests were conducted by injecting sand columns using different portland and ultrafine based grouts, the measuring penetration distances after applying equal injection pressure for the same time period. Results of tests performed in 1999 and 2000 are discussed herein.

Jan 1, 2001

By Neil J. Mansfield, Setsuo Maeda

The purpose of using experimental subjective and/or perception methods is: (a) to understand human subjective impressions of the physical characteristics of vibration; (b) to determine the relationship between the subjective perception of some aspect of the vibration and an evaluation index of the physical vibration characteristics; and (c) the establishment of target values for design of vibration environments in terms of human sensation of vibration characteristics. In order to understand the relationship between a physical measure of the mechanical vibration and the subjectively perceived aspect of the vibration environment, experimental methods shown in Table 1 have been used1. [ ] The constant measurement methods of Table 1 are mainly used for measurement of the threshold of human sense. The subjective scaling methods are mainly used for obtaining subjective (or proportional) scaling between the perceived quantity and physical quantity. In this review, the fundamental approach of experimental methods for obtaining the target values used in the design of vibration environments, and the different findings between the subjectively perceived methods for evaluating human response to vibration characteristics and the physical quantity of the vibration environment are summarized. Fundamentals of Subjective Scaling The relationship between the experimental psychological methods for providing target values in the design of the vibration environments and the physical quantities is illustrated in Fig. 1. Vehicle mechanical vibration can be characterized using many metrics, and these can be considered the ‘input’ to the human. In order to predict subjective responses to the vibration, it is necessary to link the characteristics of the source of vibration and human reactions, the ‘output’.

Jan 6, 2006

Review of the mining legislation in New Zealand has coincided with a number of radical changes. These include a redirection of economic management towards a more open and competitive economy; major reform of the state sector aimed at greater efficiency, transparency and accountability; a new environmental administration; and a fundamental review of policy for management of natural and physical resources. These changes provide an opportunity to develop a consistent and coherent approach in the minerals and related statutes that will achieve objectives of economic efficiency, equity, practicability and good environmental management.

Jan 1, 1987

By James J. Meadows, Jason D. Pampena, Emanuele G. Cauda, Lauren G. Chubb

Exposure to respirable crystalline silica (RCS) can cause serious and irreparable negative health effects, including silicosis and lung cancer. Workers in coal mines have the potential of being exposed to RCS found in dust generated by various mining processes. The silica content of respirable dust in one single mine can vary substantially over both time and location. The current monitoring approach for RCS relies on the use of traditional air sampling followed by laboratory analysis. Results generated using this approach are generally not available for several days to several weeks after sampling, and this delay prevents timely and effective intervention if needed. An alternate analytical method is needed to reduce the time required to quantify the RCS exposure of mine workers. The National Institute for Occupational Safety and Health (NIOSH) has developed a new method using commercially available portable infrared spectrometers for measuring RCS at the end of the sampling shift. This paper will describe the application of the new field-based RCS analytical process for coal mines, including the use of the new method with the existing Coal Mine Dust Personal Sampler Unit. In a case study conducted by NIOSH with a coal mine operator in West Virginia, field-based RCS analysis was completed at a mine site to evaluate the new technique. The RCS analysis results obtained by the field-based method in this case study showed sufficiently strong correlation with results obtained by the MSHA standard laboratory analysis method to allow the mine operator to use the field-based method for evaluating process improvements.

By Judy K. Todd

Double benching has been utilized as an excavation technique in open pit mines for many years. This process involves drilling, blasting, and excavating the material for the design bench height. A second bench is then excavated without the creation of a catch bench, i.e. only minimal offset from the first bench face is allowed when drilling off the second bench. The result is a double high bench face or double bench. When drilling off the second bench, the offset of the drill from the bench face projects the lower bench face into the pit up to an extra five meters. This reduces the maximum attainable bench angle, enhances the probability of rock escaping the catch bench and increases the overall strip ratio. The generally utilized process of trim blasting also can impact on the final bench profile by contributing to blast damage of the face. BHP Billiton Diamonds Inc., Ekati Mine Diamond MineTM, has pioneered the usage of a technique that eliminates this offset. Double benching is accomplished by drilling a single, 30m pre-shear (two 15m benches) to define and protect the final bench profile. This article provides a comparison of the attained face angles obtained in the field utilizing both of the above methods, as well as a comparison with the analytically predicted angles prior to excavation.

May 1, 2002

By Peter White

Mine Planning Shaft Collar Shaft Sinking Raises Ramp Underground Water Storage

May 1, 2009

By P. Lefebvre, J. Sargent, K. Major, B. Darnton

"Stillwater Mining commenced mining operations at Nye, Montana in 1987 for the recovery of platinum and palladium. Exploration identified that the J-M Reef extended for 43 km. In 1998 Stillwater Mining made the decision to develop the East Boulder mine complex, located approximately 13 miles from the Stillwater mine complex at Nye, to increase production. This paper describes the design, construction, and start-up of the East Boulder process plant.INTRODUCTIONStillwater Mining Company have been producing Platinum and Palladium from their Nye, Montana operations since 1987. The mine production from Nye had been increased in stages with mine production being delivered through several portals and one vertical shaft.The deposit is narrow veined which prevents the application of bulk mining methods and thus limits the production capabilities.In order to increase the production of platinum (Pt) and palladium (Pd) Stillwater made the decision to access the ore from the J-M Reef from the East Boulder site. The East Boulder mine site is located about 21 km (13 miles) from Nye, however as shown in Figure 1, the travel distance is closer to 188 km (114 miles). Distance, on strike, and space availability at Nye precluded the expansion of the Nye concentrator to handle the increased mining rate and supported the decision to install a new concentrator at East Boulder."

Jan 1, 2003

By Barnet Clemente, David Huaman

El sostenimiento de las labores en las operaciones mineras, son cada vez más consistente y seguros con la aplicación del concreto lanzado, en la unidad minera cerro lindo se ha migrado a este tipo de sostenimiento en un 100%. Todas nuestras labores están sostenidas con shotcrete, incluso el frente de la labor aplicamos el sostenimiento con shotcrete, que llamamos malla de sacrificio, sin embargo este tipo de sostenimiento es costoso, pero te da muchas facilidades para mejorar los rendimientos y se hace más segura la mina, para lo cual contamos con una planta de concreto exclusivamente para este servicio, con una capacidad de 30 m3 por hora, lo que necesita la mina es 7000 m3 mensuales para cubrir todas la labores de producción, preparación y desarrollo, incluso hemos considerado la labores de rehabilitación y resanes por la misma operación minera, esta operación nos da una demanda de 9 mixcrets en operación y un stand by, con 4 alphas operativos y 1 en stand by.

Sep 1, 2017

By P Williams, S Flynn, R Birchfield, R Simcock, R Toft, P Comeskey

Direct transfer, or community translocation, comprises salvage and replacement of intact æsodsÆ of vegetation together with underlying soil. It has been applied to New Zealand mine sites restoration of native grasslands, wetlands, scrub lands, and forest. It is an equivalent technique to æinstant lawn or tree gardenÆ, commonly used in urban landscaping. Two to six m2 scoops of vegetation, with up to 0.7 m of soil attached, and including root plates of trees and shrubs, are relocated from stripped areas ahead of mining to sites prepared for restoration. Direct transfer uses hydraulic excavators or face shovels and dump trucks, possibly with the aid of bulldozers and other earthmoving machinery. The main advantages of direct transfer, compared with sowing or planting systems for mine site restoration, are the recycling of plant and soil materials which were often wasted by burying under overburden materials, a significantly faster revegetation process, and restoration of the whole ecosystem (plants, animals, birds, invertebrates, and microbes). The main disadvantages are higher costs of stripping and dumping, a greater degree of machine operator skill required, and scheduling becomes critically important. To illustrate the key principles, this paper gives examples of successes and failures of the technique for a variety of New Zealand mining situations. Direct transfer has been successful for a range of communities, from fern wetland and sub-alpine tussock grasslands to 5 m-tall beech forest under storey and seral shrub land, and from temperate to sub-alpine climates. Successful examples show both rapid recovery of indigenous vegetative cover and conservation of habitat for birds and invertebrates. Failures have resulted from excessive death of plants because of inadequate soil salvage depths, acidic leachates, inappropriate handling of stripped sods by inexperienced machinery operators, or prolonged drought conditions immediately following relocation. Change in plant species composition has occurred where clumps of vegetation are too far apart, or shifted plants were too small - in both cases invasive weeds have smothered the original vegetation. Changes in hydrology can also have significant impacts. Our experience indicates that the advantages of direct transfer far outweigh the disadvantages and is now used as the preferred restoration method, where practicable, at mines where it has been trialled.

Jan 1, 2000

By Garry Biles

The Eskay Creek Mine is a high-grade gold and silver underground mine in northwestern British Columbia. The mine started operations in late1994. For the first three years, ore was crushed to -50 mm(-2 in.), blended to satisfy smelter terms and shipped to smelters in Japan and Canada. Preliminary evaluations indicated that a complex metallurgical facility, requiring a large capital investment, would be required to recover the precious and other economic metals. So markets for raw ore were identified and underground mining and ore transportation operations began at a production rate of 300 t/d (330stpd).

Jan 1, 2000

By Wolfang Ladewg

Desde enero hasta agosto de 1965 se probó un prototipo del telémetro electro-óptico EOS de VES Carl Zeiss JENA, a través de las mediciones en unos 70 días. En ese sentido, el objetivo del presente texto es determinar la exactitud de medición, así corno la constante de adición y el alcance del EOS. Para ello, se midieron distancias geodésicos a base estandard en los campos de ensayo geodésicos de Potsdarn y en una red de ensayo determinada trigonométricarnente. La medición de las distancias se realizó en tres días, empleándose un reflector de siete prismas con sus correspondientes cuñas adicionales. Mientras que en los campos de ensayo geodésicos se midieron 19 distancias entre O, 1 y 7,5 km. Las mediciones se efectuaron en un espacio de tres meses en total con diferentes números de series

Nov 1, 1970

By Germán Mallén

Como parte de los estudios línea base realizados por MWH Perú S.A. para el proyecto aurífero Chucapaca de las Canteras del Hallazgo en el distrito de Ichuña de la región Moquegua, Perú, se investigó el origen de boro, alta salinidad y otros componentes que perjudican la aptitud de los ríos Ichuña y Tambo para irrigación y otros usos. En este sentido, se encontró que la calidad de agua es perjudicada principalmente por altas concentraciones de sodio, entre otros, precipitándose como hidróxidos de estos metales debido al pH neutro en el río. En ese sentido, el presente texto describe la relación de este impacto químico con los manantiales entre el Cerro Chucapaca y el cañón del Río Ichuña/ Alto Tambo, ubicados al Norte de Moquegua, donde presentan la característica distribución de diferentes tipos de aguas volcanogénicas sobre un sistema de convección hidrotermal de agua meteórica profunda reciclada, calentada y movida por una cámara magmática andesítica que aporta calor y gases.

Sep 21, 2013

By R. A. Franks

An evaluation of a nuisance-emissions-discriminating smart mine fire sensor system was made in an operating coal mine. These field evaluations were conducted to determine the sensor system?s ability to discern nuisance emissions, such as diesel exhaust, emissions from flame cutting and welding operations or hydrogen gas from a charging station, from real fires and to compare the number of falsely reported fire alarms generated between the sensor system and a standard carbon monoxide (CO) monitor. The sensor system?s ability to operate successfully in the working environment of an operating coal mine was also evaluated. The smart mine fire sensor system consisted of four sensors whose data outputs were fused with the use of a neural-network-type computer program. Long-term trials were conducted in a haulage way, a belt entry, and a track entry. The system functioned successfully in the belt entry, in accordance with its developmental goals, where the sensor system even discriminated events not anticipated during development. It was not totally effective in the haulage way and track entry, though, due to a combination of significant diurnal air temperature variations, dust, and mechanically induced vibrations. Also, deteriorating rib conditions contributed to operational problems in the haulage way evaluation. In general, the smart mine fire sensor provided nuisance emissions discrimination and was shown to be a viable new approach for mine atmospheric monitoring, enhancing miner safety. This paper describes the in-mine evaluation of the smart mine fire sensor system and discusses recommendations for improving the system. Disclaimer: The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the National Institute for Occupational Safety and Health.

Jan 1, 2008

One of the chief drawbacks to Bendigo mining always has been the difficulty of draining the mines in an equitable manner, so that each company or mine owner bears the properly share. The trouble seems to have been apparent on this field since the diggings were discovered. One mine would push on more expeditiously than its neighbour in looking for the precious metal and sink its shaft, whilst those in the vicinity would simply potter about, and discontinue sinking until gold was struck in the deeper ground, and: then they would go ahead, start sinking, while the pioneer would have to pump all or most of their water. This sort of thing continued here for years until the leases were worked down to the very deep ground and the water became such a b.urden on those companies that had deep shafts, that first one stopped hauiing and then others; with the result that over 1000 feet of water was allowed to accumulate on the New Chum line. lt appeared that if something were not done the whole of the main line of reef in the Bendigo district would be at a standstill, when a scheme was formulated and handed to Mr. Lansell, who, with other gentlemen, took the matter up, and at the present time all the mines on that particular portion of reef are in full work and the water all bailed out.lt is this scheme that I am requested to place before you and also to give you the details of the work done since its adoption.

Jan 1, 1902

By Frank Armstrong

ALL the mining machinery of the Penn Iron Mining Co. has been operated by electric power for several years and when another shovel for stockpile loading was required the advantages of an electric shovel were naturally considered. After considerable study, serious objections suggested themselves the use of a shovel operated directly by electrical apparatus by reason of the complicated control, severe service on the motors FIG. 1.-ELECTRO-HYDRAULIC SHOVEL FIG:. 2-THE SHOVEL AS IT WAS OPERATED CINDER CONSTRUCTION. THE FIRST YEAR. and the heavy surges of current required from the line. It was finally decided to construct an electro-hydraulic shovel using water under pressure to perform all the necessary operations except that of propelling, for which a separate motor was best suited. A car body with boom, dipper handle and dipper of late design, but without any of the steam machinery, was purchased. A motor-driven centrifugal pump, a pressure tank, an air tank, a small air compressor and water cylinders with plungers, pistons and valves, were installed in place of the; steam equipment. Fig. 1 shows this shovel under construction and Fig. 2 shows it as it was operated during the first year, the summer of 1914. The large tank at the back of the car, in Fig. 1, carried air under

Jan 2, 1916

By K. Y. Lee, J. M. Park, C. W. Park

Laboratory-scale experiments were carried out to investigate the effect of ladle slag composition on the decreasing behaviour of aluminum content in steel, i.e., reoxidation of molten steel in contact with slag, using a vertical tube furnace. The steel composition and the slag system chosen were for ultra low carbon and CaO-Al2O3-FeO-MnO-MgO based to simulate ULC steel grades. It has been observed that the reoxidation rate shows a good relationship with (T. Fe) content in slag. In case of (T. Fe) content higher than 1.5 weight per cent, the reoxidation rate increases linearly with increasing (T. Fe) content. For a given (T. Fe) content, it decreases with the increasing (CaO)/(Al2O3) ratio of the slag. However, in the case of (T. Fe) content lower than 1.5 weight percent, no particular relationships are observed between the reoxidation rate and (T. Fe) content or the (CaO)/(Al2O3) ratio of the slag. These results were used to propose for an aim a slag composition for the ULC steel grades in a steelmaking plant. Keywords: slag deoxidation, slag killing, slag composition control, IF steel, ULC steel grade

Jan 1, 2004

By Jhonny Torre, Mario Carpio, Elmer Boulangger, Jesús Fuentes

El INGEMMET, a raíz de la importancia del avance energético y de las innovaciones tecnológicas, propone entre los años 2015 a 2017, realizar estudios en ambientes primarios pegmatiticos-intrusivos y metamórficos tanto en las unidades morfoestructurales de la Cordillera Oriental y Cordillera de la Costa, para definir ocurrencias y futuros depósitos que albergan litio en el Perú. Entre los años 2018 a 2019, INGEMMET, por intermedio del programa de Rocas y Minerales Industriales, de la Dirección de Recursos Minerales y Energéticos (DRME), realizó dos proyectos denominados GE34 A-5: “Prospección regional de Litio en el Sur Peruano” y GE34 A-6:“Prospección regional de Litio en el Centro y Norte del Perú”, para determinar ambientes geológicos favorables en relación a valores anómalos de litio en el Perú

Sep 30, 2022