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By I. L. Nichols, K. C. Dean, P. H. Johnson

Hydrochloric acid , sulfuric acid , and chloridizing roast- water leaching methods for dissolution of cesium and rubidium from Maine , Canada , and Southern Rhodesia pollucite ores and their flotation products were investigated by small- scale tests . Optimum conditions were determined to be ( 1 ) for hydrochloric acid leaching , use 12.7 equivalents of 8.8 normal acid per equivalent of cesium in the sample and leach for 6 hours at 100 ° C ; ( 2 ) for sulfuric acid leaching , use 12.7 equivalents of 14.4 normal acid and leach for 2 hours at 120° C ; and (3 ) for chloridizing roast - water leaching , roast minus 200 - mesh ore, limestone , and calcium chloride in a ratio of 2 : 4 : 1 , respectively , for 1 hour at 900 ° C , and leach the calcine for 1 hour at 80 ° C with enough water to give 35 pct solids . Extractions of cesium from ores and flotation products containing over 20 pct cesium were in excess of 97 , 93 , and 96 pct for the hydrochloric acid , sulfuric acid , and chloridizing roast - water leach processes , respectively .

Jan 1, 1964

By Charles H. Bucknam

A gold sampling optimization study was carried out in support of open pit gold mining operations for the Newmont Gold Company Bootstrap-Capstone deposits in Northeastern Nevada. Six bulk samples were tested using fire refining techniques at field particle size, to determine coarse particle heterogeneity of the ores, and by gravity .concentration methods at 10 mesh particle size, to observe any particulate gold liberation. An overall sampling model is presented for the deposit based on the pooled test information, to reconcile the results of coarse particle heterogeneity testing and the fine particle 'liberation testing. The sampling model is used to recommend procedures to control the variability of gold grade estimation due to the fundamental error (nugget effect) during sampling, sample preparation and assaying of the ores and other fundamental variances. The technique of simplified quantitative risk analysis (SQRA) is used to provide an economic justification for implementation of. recommended improvements to field sampling practices.

Jan 1, 1999

By Shiqiang (Rob) Hui, Jiaren (Jimmy) Jiang, Rees Llewellyn, Yongsong Xie

Wear has been estimated to cost the Canadian mining/mineral processing industry over $15 billion per year mainly for repair/replacement of worn parts in 2013. The associated production loss is difficult to quantify but add considerably to the problem. The Canadian oil sands sector which has to deal with extremely abrasive and erosive solids, has traditionally incurred extremely severe and often unique attack. Demonstrable progress in mitigating the wear problems has been achieved through materials development, more informed materials selections, and better component and operation condition designs. An integral contributor to these advances is a long-term collaborative research partnership between NRC and the mining/supply industry. In this paper, this continuing collaboration will be described. A main focus is to identify degradation mechanisms occurring in the most severe and important service applications and to correlate these findings with laboratory test data. Relevant abrasion and erosion (often combined with corrosion) properties have been established and correlated with composition and microstructures for all classes of resistant materials ranging from relatively soft elastomers to ultra-hard ceramics. A comprehensive wear properties database has been compiled. This capability has been instrumental in facilitating the development of improved materials, optimizing materials fitness/selection for service, wear failure analysis, and quality assurance.

Jan 1, 2015

By C Fong

Compliance Planning is an active approach to ensure mining operations align more closely to their longer-term plans. Through Compliance Planning, operations can not only measure their performance on intervals as short as intra-shift, but they can then apply corrective measures to ensure they remain as close as possible to the plans. Compliance Planning targets short-term and execution level teams, as these are the shortest duration planning divisions commonly found in mining operations. Compliance Planning combines live information with intelligent planning capabilities to provide a framework that enables mining operations to realise a significant improvement in reconciliation of plan to actual movements.

Jun 22, 2022

By Simón D. Strauss

El presente texto señala los factores que han influenciado el comportamiento de los precios de los metales no ferrosos desde el fin de la Segunda Guerra Mundial. Tras la finalización de este periodo bélico, se dio una inflación que afectó los niveles de precios de todos los productos, alterándose los costos de cuatro de los ocho metales no-ferrosos en la industria minera peruana. Para ello, se realiza un estudio comparativo de los precios estipulados durante la Segunda Guerra Mundial con los precios vigentes al 31 de octubre de 1969. Asimismo se analiza los problemas básicos de oferta y de demanda, encontrándose que la demanda es mayor a la oferta, pese al descubrimiento de nuevas reservas del mineral. En consecuencia, tanto el avance científico y tecnológico como el desarrollo de la competencia son factores de importancia en la tasa de mercado actual que necesitan evaluarse constantemente.

Nov 20, 1969

By R. E. Gertsch

Mechanical mining holds great promise for the mining industry. Realizing this promise depends on giving mine operators the capability to evaluate the higher production, the lower costs, and safety enhancement that comes with mechanical mining. The opportunities for low cost and high production must outset the high capital costs associated with mechanical excavation. Giving the mining industry the tools to effectively evaluate and successfully implement mechanical methods defines the challenges and directions of the mechanical mining industry.

Jan 1, 1994

By R. L. Solmer

During 1959-61, the Bureau of Mines investigated the strain and deformation induced in rock and concrete linings around mine openings by retreat panel caving at the Climax Molybdenum mine. Two concrete-lined slusher drifts on the Phillipson level of the mine were instrumented with both electrical strain gages and extensometers. Changes in strain and deformation were recorded over an 18-month period during the undercutting and caving of the mining panel. General agreement was found between the strain and deformation measurements and the hypothesis that the vertical component of the stress field on the openings is almost completely removed by undercutting. This phenomenon is a possible explanation for the structural failures that occur in the slusher drifts during the undercutting cycle.

Jan 1, 1965

By MattelmSki M

Outokumpu Harjavalta Metals Oy has been producing nickel since 1962, based on conventional flash smelting technology followed by electrowinning of nickel. In the 1980s, a research project was initiated to develop a converterless direct smelting process to produce matte for further refining in the then existing refinery. The process was tested on a pilot plant scale at Outokumpu's research centre in Pori and was found to be viable. The process was named the Direct Outokumpu Nickel Smelting Process or the DON Process. At the turn of the 1990s, Outokumpu studied various options to develop its nickel business and the Harjavalta operations. As a result of this work, the DON Process was further developed to produce two mattes: low iron matte in the flash furnace to be leached in the existing leaching circuit and high iron matte in the electric furnace to be leached in the new leaching circuit. In Harjavalta's case, it was essential and important that the process could use the existing flash furnace and electric furnace without converters.

Jan 1, 1996

By R. D. Brown

The Federal Government's White Paper on Tax Reform received further major criticism in the reports of the Committees of the House of Commons and the Senate, which recently completed a lengthy review including public hearings of the government's proposals. These reports both criticized the emphasis placed by the White Paper on its concept of tax equity rather than on a system which would promote economic growth. However, the Finance Committee of the House of Commons was prepared to accept, with modifications, a number of the White Paper's key reform proposals. The Senate Finance Committee was more critical of the basic thrust of the tax reform program and recommended that a modification of the existing tax system would be more appropriate to Canada's needs. Both Committees re-commended a more favourable treatment of mining income than that originally proposed in the White Paper, and to some extent both Committees suggested proposals that were even more favourable to the industry than those set out in Finance Minister Benson's amended proposals made in August of this year. This article out-lines the principal recommendations and comments in the reports of both the House of Commons Committee and the Senate Finance Committee.

Jan 1, 1971

By M. Saghaeian, R. Hejazi, R. Barreiro, M. Tavousi, M. Ahadi, O. Asghari

"Banded iron formations are the major iron source for producing high grade concentrate. BIF are generally lower grade and more difficult to extract. In order to know how best to process BIF ore, it require comprehensive knowledge on ore bodies even in the early stages of the mining process. Geometallurgy combines geological and mineral processing information and allows for higher flexibility in response to changes in the plant feed when mining different parts of the ore. This can lead to economic benefits, owing to improved plant operation, yet is time consuming and correspondingly costly. The main focus of this paper work has been to develop a comprehensive geometallurgical testing framework for developing Yogi BIF low grade magnetite deposit located at Western Australia. In order to provide successful geometallurgical mapping, was collected data from several different disciplines (geology, chemistry, mineralogy) and parameters (physical properties, metallurgical response and geotechnical measurements) during drilling activities and test work. The investigation shown magnetic separation behavior of material had high variation and is most important element in the proper design of ore beneficiation plant. This paper provides an improved and efficient magnetic separation test methods used for the investigation of separation behavior and variability of the Yogi Ore deposit and evaluates their applicability and potential in the geometallurgical context. In this paper a small-scale magnetic separation has been developed that allows estimating from single pass separation test using small amounts of sample material. Verification of the evaluation method and validation was done with different mineral systems."

Jan 1, 2018

By Marcos Paulo Kohler Caldas

Após a sanção da RoHS Directive 2002/95/EC que entrou em vigor em 01/07/2006 proibindo a utilização de seis substâncias perigosas, sendo elas: chumbo, mercúrio, cádmio, cromo hexavalente, bifenilos polibromados e éteres difenil-polibromado fabricantes de equipamentos eletroeletrônicos tiveram que restringir os usos de tais substâncias. Com isto, as placas de circuito impresso dos equipamentos passaram a ser identificadas com a sigla RoHS ou outra identificação que indique o atendimento a diretiva. O presente trabalho visa analisar um lote de placas mãe de computadores obsoletos direcionados ao CEDIR-USP (Centro de Descarte e Reuso de Resíduos de Informática) no período de 01/01/2013 a 30/05/2013, identificando-as como “lead free” ou “comuns”, a fim de verificar a relação entre placas livres de substâncias perigosas e placas contendo tais substâncias. O lote possuía quantidade aproximada de 3.230 placas. Após a separação, as placas “lead free” foram classificadas por marca e nacionalidade. O resultado da pesquisa mostrou que mesmo após onze anos da edição da diretiva o percentual de placas livres de substâncias perigosas ainda é muito baixo. Cerca de 97,80% das placas de circuito impresso coletadas ainda possuem em sua composição substâncias perigosas. Verificou-se que todas as placas “lead free” encontradas são de origem chinesa e seus fabricantes são: Gigabayte, Itautec, Intel e CE. O estudo também classifica a origem dos resíduos como: industriais, da própria universidade ou residenciais.

Aug 8, 2018

By R LEATHAM

Long hole drilling underground has come a long way since 'down the hole' surface drills were first taken underground. The underground miners have progressively developed the use of long hole stope drilling from the 'quarry blast' to a precise and selective removal of ore while leaving the remaining structure as undamaged as possible. To reach this position has involved the development of equipment and explosives to give the desired results. This paper reviews some aspects of long hole stope production drilling.

Jan 1, 1992

The primary steel industry of the Prairie Provinces consists essentially of three companies whose total annual melting capacity, as of January 1, 1963, was 333,000 net tons. These companies have steel rolling facilities. In addition, there are five other companies producing steel castings by melting scrap in electric furnaces which, with the plants having rolling facilities, gives a total annual furnace melting capacity of 380,000 tons. Since 1954, the annual production of steel ingots and castings has ranged from a low of 66,588 tons, in 1954, to a high of 211,138 tons in 1961. The present facilities on the Prairies for making steel ingots from scrap, and rolling them to produce light merchant mill products, appear to be sufficient for many years ahead. Steel scrap, as electric furnace feed to make steel ingots for the present line of products, will probably continue to be available at reasonable prices either on the Prairies or from the north-central United States. It is recognized, however, that residual elements in scrap may be-come of greater significance and necessitate more rigid control of scrap quality.

Jan 1, 1963

By E. R. Bauer

A primary goal of Ground Control Research, Bureau of Mines, U.S. Department of the Interior, is to develop information that can be used by the mining industry to reduce accidents and fatalities due to failure of mine roof. A specific research objective is to determine methods to detect hazardous coal mine roof. This paper reviews the existing and experimental techniques, and describes a recent Bureau of Mines contract research project that resulted in a simple technique and prototype instrument for evaluating mine roof competence.

Jan 1, 1986

By William J. Campbell

The columbite-tantalite mineral series was studied by various instrumental techniques to establish the relationship of density to composition. The samples used were carefully selected to obtain a mineralogical purity of at least 98 percent. Impurities were determined by optical microscopy, X-ray diffraction, and optical and X-ray spectroscopy. Each sample was analyzed by fluorescent X-ray spectroscopy for iron, manganese, columbium (niobium), and tantalum. The existence of a unique relationship in this isomorphous series permits a simple correlation of the intensity of a spectral line with the concentration of the analytical element.

Jan 1, 1955

Although mining, particularly of gold and coal, played a significant role in the development of New Zealand, from the time of the spectacular gold rushes of the 1860s its economic importance to the country as a whole has decreased substantially since that time. Gold, coal and non-metallic agricultural and industrial minerals have been found in economically significant quantities, however, the search for base metals has not been successful.

Jan 1, 1982

By W. R. Reed, D. E. Pollock, T. W. Beck, J. A. Organiscak, J. D. Potts

In underground continuous mining operations, ventilation, water sprays and machine-mounted flooded-bed scrubbers are the primary means of controlling respirable dust exposures at the working face. Changes in mining arrangements — such as face ventilation configuration, orientation of crosscuts mined in relation to the section ventilation and equipment operator positioning — can have impacts on the ability of dust controls to reduce occupational respirable dust exposures. This study reports and analyzes dust concentrations measured by the Pittsburgh Mining Research Division for remotecontrolled continuous mining machine operators as well as haulage operators at 10 U.S. underground mines. The results of these respirable dust surveys show that continuous miner exposures varied little with depth of cut but are significantly higher with exhaust ventilation. Haulage operators experienced elevated concentrations with blowing face ventilation. Elevated dust concentrations were observed for both continuous miner operators and haulage operators when working in crosscuts driven into or counter to the section airflow. Individual cuts are highlighted to demonstrate instances of minimal and excessive dust exposures attributable to particular mining configurations. These findings form the basis for recommendations for lowering face worker respirable dust exposures.

Jan 1, 2016

By Jorge Luis Barreto

A CBMM aplicou aços microligados ao nióbio de elevada resistência mecânica em caminhões basculantes que operam nas suas instalações de Araxá, com o objetivo de reduzir o peso das caçambas e obter maior desempenho com aumento da carga transportada, redução do consumo de combustível bem como das emissões de CO2. Também tinha o objetivo de eliminar as trincas de fadiga que ocorriam sobre os chassis desses equipamentos. Os caminhões já operam há 12 meses e o objetivo desse trabalho é apresentar os resultados obtidos até o momento. Com a aplicação dos aços de elevada resistência, foi possível desenvolver um novo desenho para sua estrutura e componentes. Houve uma redução de 25% da massa da caçamba o que proporcionou um aumento médio de carga transportada de 40,0t para 41,1t ou 2,7% por viagem, trazendo até o momento, economia de 3,00% no custo total de transporte e redução de consumo de combustível de 8,00%. Não houve trincas ou deformações no sobre chassis que apoiam as caçambas.

Aug 8, 2018

By L. R. Hougen

The Falconbridge Matte Leach Process yields high-purity nickel chloride by selectively dissolving nickel from copper-nickel converter matte with hydrochloric acid , purifying the solution by solvent extraction and crystallizing NiCl2 4H2O by further acidifying the purified leach liquor. In the Kristiansand Matte Leach Plant, a granular oxide is produced by high-temperature hydrolysis of the nickel chloride for subsequent reduction to a high-purity granular metal product, designated NICKEL 98. This paper describes the investigation of on alternate route to processing nickel chloride in which high-quality cathode nickel is produced by electrowinning from all- chloride electrolyte. The investigation was made in a pilot circuit containing two production-size electrowinning tanks operated in conjunction with the commercial-scale leach plant.

Jan 1, 1977

By L. Yuan, J. H. Rowland, R. A. Thomas, D. Bahrami, G. P. Cole

"The past several decades have seen a steady increase in the use of atmospheric monitoring systems (AMS) in underground mines as sensor technology has advanced and costs for this technology have decreased. The AMS is a reliable tool for early mine fire warning by detecting gaseous products of combustion in underground mines. During a mine fire emergency, mine decision makers rely heavily on the prompt and accurate knowledge of the ventilation and fire situation in the mine, such as fire location, fire size, and the spread of smoke to make effective and efficient decisions on firefighting strategies and miner evacuation. Meanwhile, a prediction of the potential for fire development at a later time, such as whether the currently designated mine escapeways will be contaminated by smoke and toxic gases with the progress of the fire, is critical for effective decision-making to save lives that are in danger. The AMS monitoring data, including carbon monoxide (CO) concentration, airflow rate, smoke, etc., can provide information as to whether the smoke has reached the locations where AMS sensors are installed and if a mine-wide smoke spread has occurred. The National Institute for Occupational Safety and Health (NIOSH) has undertaken a task to integrate real-time AMS monitoring data with the mine fire simulation program, MFIRE, to simulate and predict the spread of smoke and toxic gas in a ventilation network based on the real-time AMS data. This paper reports the developed real-time method for characterizing the size and location of an underground mine fire and for predicting the spread of contaminants throughout the mine ventilation network using sensor data from the AMS.INTRODUCTIONNIOSH conducts research to develop workplace solutions to improve detection of and reduce the risk of hazardous conditions in underground mines. The advancement of senor technology and the increasing demand for real-time mine parameters monitoring have led to extended applications of atmospheric monitoring systems (AMS) in underground mines worldwide. In the United States, AMS is primarily used for early mine fire warning by detecting carbon monoxide (CO) in fire hazard areas, such as belt entries. Mine fires can grow rapidly, and time is the critical element. Prompt detection, timely and accurate warnings to those miners potentially affected, and a proficient response by underground miners can have a tremendous impact on the social and economic consequence of a small underground mine fire (Conti et al., 2005). The early detection of a mine fire could gain time for the first responders to put out the fire before it develops into a disaster. An AMS system with CO sensors has especially played an important role in the early detection of mine fires. The continuous monitoring of an underground mine atmosphere with an AMS could generate a large amount of data in a mine fire event. However, the current application of AMS is mainly limited to sending out an alarm when monitored CO concentration exceeds a certain level. An opportunity arises as to whether these data can be further used in fire emergency response. In order to make effective decisions on firefighting strategies, mine workers’ seeking refuges, evacuation and escape, and the timing on when to send rescuers, decision makers need accurate and timely knowledge of the ventilation and fire situation in the mine. Information about the fire intensity, where in the mine the smoke and toxic gases have spread, and whether designated mine escapeways have been compromised by smoke and toxic gases from the fire would greatly increase the effectiveness of these decisions. However, the monitored AMS data only provides atmospheric conditions in the vicinity of sensor locations. What is concluded from the monitored AMS data highly depends on the decision makers’ capability and experience. Predictive insight into fire growth and smoke transport would greatly help decision makers during a fire emergency."

Jan 1, 2019