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By L. Chunpongtong

The mining limit in oil sands is regulated by the ratio of total mining volume (ore, interburden, and overburden) one has to mine per volume of bitumen in place (TV/BIP). This paper presents a mathematical solution for creating the most economical pit outline where the TV/BIP ratio upper limit is 12, by combining mining economic theory and the Lerchs-Grossmann (LG) algorithm.

Jan 1, 2014

By D. Sprott, P. A. Kirsch, J. Harris, D. Cliff

This paper details the work of RISKGATE, the largest Australian Coal Association Research Program (ACARP) occupational health and safety initiative to date. The program is an interactive online risk management system developed to maximize health and safety performance in the coal mining industry by implementing continuous improvement in managing major unwanted events. The comprehensive knowledge base covers tires, collisions, fires, isolation, strata control underground, ground control open cut, explosions, explosives, manual tasks, and slips/trips/falls. All major Australian coal mining companies contributed topic experts to this broad industry initiative: nine coal mining companies, more than 80 experts, and more than 400 days of individual time for knowledge-capture workshops.

Jan 1, 2014

By E. Michelotti, M. Cardu

This paper presents the results of a new method that has been tested to recover metallic cobalt lost by diamond beads from rock cuttings. When dimension stones are cut using diamond wire saws, the beads become worn and, before the end of their cycle life, lose a certain amount of material; this material is prevalently made up of sintered metal and diamonds. The material is then washed away, together with rock debris, in a dilute pulp. In effect, this process involves the dispersion of economically valuable, but potentially polluting, materials (such as cobalt) that are used to confer indispensable technological features to the beads. This current research aims to develop a waste-processing pilot plant (High-gradient Magnetic Separator or HGMS) to recover metallic components from the pulp by means of a suitable separation. The research\u2019s purposes are two-fold: a. to remove the polluting components from the rock debris before their disposal and b. to start a recycling process of the valuable metals.

Jan 1, 2010

By A. Galley, R. Tosdal, F. Robert

The Canada Mining Innovation Council (CMIC) Exploration Innovation Consortium developed a 10-year business case for developing new discovery criteria, exploration techniques, and better data management and analysis to improve exploration success in deep, remote, and covered terrains. Within this context, the CMIC devised a five-year project proposal to create improved multiparameter exploration tools to detect ore systems and more efficient vectoring toward high-grade mineralized cores. The Footprints project was approved March 2013. More than CAD$13 million funding was provided through the CMIC-led joint sponsorship from 30 companies and the Natural Sciences and Engineering Research Council. Consistent industry leadership and integration of dedicated industry and academic expertise has the project on track for reaching its well-defined objectives.

Jan 1, 2014

By J. S. Laskowski

Anisotropic minerals are important constituents of many ores. This group includes both valuable minerals (e.g., molybdenite in Cu-Mo ores) as well as gangue minerals (e.g., talc in platinumbearing sulphide ores in South Africa, graphite in Cu-Ni sulphide ores in Canada, chrysotile in Ni sulphide ores in Australia, and clay minerals in all types of ores). Aqueous suspensions of anisotropic minerals exhibit different properties than suspensions of isotropic minerals. The presence of anisotropic minerals in flotation circuits affects the flotation process.

Jan 1, 2012

By A. McQuillan, N. Bar

Geotechnical engineers are routinely tasked with advising suitable stand-off distances below highrisk sections of slopes in open-pit mines that are identified to have potential to deform or collapse. Accurate prediction of failed material runout can mean the difference between continuous safe mining and unwanted high-potential incidents that result in loss of production, equipment damage, injury, or loss of life. This paper updates previous empirical relationships presented by the authors for estimating the volume and runout distance of excavated slope failures, in an open-pit mine operation, using slope geometry as the primary predictor. Cases are sourced from varying slope geometries (fall heights up to 385 m, slope angles up to 80°) and a range of commodities (iron ore, coal, nickel, gold, copper, boron, and limestone), excavated in sedimentary, banded-sedimentary, epithermal, and copper-porphyry deposits, across all six inhabited continents. Analysis of these cases identified positive correlations between slope height and runout distance, and slope height and failed material volume. In general, negative correlations were identified between Fahrböschung angle and slope height, and Fahrböschung angle and failed material volume; however, significant scatter is observed in these datasets. A definitive relationship could not be derived comparing Fahrböschung angle with failed material runout. Slope angle was also found to be a poor indicator of runout. Of the parameters analysed, slope height (i.e., fall height) was found to be the simplest and best predictor of runout distance. This paper presents new charts for predicting failed material runout distance for rock slopes. Relationships are defined for structurally and rock-mass driven slope failure mechanisms at average, 75%, and 95% prediction intervals

Jul 10, 2024

By K. G. Philo, R. C. W. Webber-Youngman

mining, where data-driven decision making optimizes resource extraction, enhances safety, and ensures sustainability. The adoption of digital technologies like artificial intelligence (AI) and the Internet of Things has amplified the importance of digital information. However, the integrity and security of this information are paramount, leading to the exploration of blockchain technology as a potential solution for secure digital value exchange in mining. This research examines blockchain's capabilities, drawing insights from its applications in sectors like banking, government, healthcare, and entertainment, and evaluates their relevance to mining's core value chain processes. The study identifies blockchain's distributed ledger technology, cryptographic security, and decentralization as unique advantages that can revolutionize mining by enhancing transaction speed, reducing costs, and improving supply chain transparency and compliance with sustainability standards. Blockchain's transparent and auditable records can enhance business transparency, fostering trust among stakeholders, including investors and regulatory bodies. The technology's consensus mechanisms and smart contracts further promote trust in collaborative ventures. This research provides a foundational understanding for decision-makers in the mining industry to evaluate blockchain's feasibility and potential return on investment, guiding strategic planning and resource allocation for blockchain applications. By leveraging blockchain, mining companies can optimize operations, improve sustainability practices, and establish a robust foundation for future growth, positioning blockchain as a transformative technology in the sector

Jul 10, 2024

By N. Mutemeri, T. -L. Field, M. Chuma

The categorization of artisanal and small-scale mining has a significant impact on perception and understanding of the sector, particularly from a livelihood perspective. Several developing countries classify different types of artisanal and small-scale mining based on legal status. Given the nature such activities, the tragedy of the commons theory has been applied to understand the inevitable environmental, economic, sociocultural, safety, and health negative externalities – which are products of informality and illegality. Consequently, formalization is a panacea to sustainability. This article aims to offer a conceptual organization and foundational knowledge for characterization of artisanal and small-scale mining. It seeks to identify existing literature on the subject to avoid replication and acknowledge other scholars. Moreover, the article aims to place the study within the context of existing literature, establishing relationships with other studies and why the research is necessary. This paper pinpoints gaps left from other studies in so far as the characterization of artisanal and small-scale mining is concerned. Thus, reviewing literature abetted in finding similarities and differences on how artisanal and small-scale mining is defined from a scholarly and legal basis. The paper ascertains major claims made by earlier research on this topic, such as environmental impacts, the lack of adequate regulatory framework, and presents querying and probing questions lacking from other studies.

Jul 10, 2024

By L. W. Palmer

Compositing or regularization of drillhole data is common practice in mineral resource estimation and is deemed a necessary step in producing unbiased estimates of mineral resources and reserves. Commonly, data are collected over irregular distances due to the varying relative thicknesses of lithologies drilled or sampling/assaying strategies. This necessitates data transformation to regular lengths of equal size to ensure that all data have the same sample support. However, there have been few detailed publications on the effect of this process on the composited data that are subsequently taken forward for the estimation process. In this paper, three currently available compositing methods are reviewed and the effects of inappropriate compositing methodologies presented. It is shown through a case study that compositing samples to different lengths leads to changes in the average and variance of the grades in the drillcores in the dataset, which will impact the final estimated value. These differences are exacerbated by breaks or gaps in data where, for a variety of reasons, there has been no data collection or data have been lost. The importance of appropriately treating blank and zero data is also presented. Globally, these differences might be minimal, but locally may be substantial, affecting the efficiency of the estimation and subsequent use of the results in, for example, mine planning and reconciliation. Further detailed investigation of compositing practices is required if the full implications of compositing are to be understood and any induced bias effectively defined.

Jul 10, 2024

By J. Maritz, K. de Beer, S. M. Buthelezi

The economic upheaval of COVID-19 forced companies to invest in emerging technologies to aid recovery. One such technology is extended reality, which is becoming a mature and innovative tool. Early adopters are seeing significant benefits in learning, training, immersive data visualization, and remote assistance. In South Africa, the mining industry is increasingly interested in using extended reality to optimize and innovate operations. The Minerals Council of South Africa's July 2021 report highlighted the potential of extended reality's to achieve zero-harm production and modernize the industry. However, the extent of extended reality adoption in mining remains unclear due to limited information on its usage. This study addressed this gap by distributing an online survey to assess awareness, knowledge, and current uses of extended reality in South Africa’s mining sector. The results indicated that virtual and augmented reality had the highest levels of awareness and usage, primarily for learning and training. Mixed reality, however, had the lowest awareness and knowledge levels. In terms of applications, visualization and remote assistance had the least use cases. These findings highlight that the South African mining industry is deficient in its understanding and use of extended reality technologies. Without better awareness and application, the South African industry risks missing out on the full benefits of extended reality. The study underlines the need for the South African mining industry to improve its outlook on extended reality technologies to fully leverage their potential applications and benefits.

Jul 10, 2024

By T. T. Chiweshe, L. S. Mokhahlane, M. Welman-Purchase

This study examined an alternative technique of extracting tungsten from wolframite ore using a fusion method with ammonium phosphate salt. Current techniques use alkali salts to decompose tungsten ores and use various purification methods to produce ammonium paratungstate, which is a key intermediate precursor in the extraction of tungsten. In this study, a two-step extraction process, which involves thermal decomposition of the ore using fusion and a separation stage, is examined. The novelty of this technique is the ability to completely decompose wolframite ore and form an unstable tungsten oxide phosphate (WO2(PO3)2) compound. The instability of WO2(PO3)2 in deionized water enables selective isolation of tungsten as insoluble precipitates of WO3 and WO2. The decomposition reaction of WO2(PO3)2 is influenced by the presence of oxygen and determined to be first order under ambient conditions. Scanning electron micrographs and X-ray diffraction analysis showed above 80% of the tungsten precipitated compared with the amount that remained in the filtrate solution.

Jul 10, 2024

By B. Ceki, A. Mabentsela

The BCL furnace is scheduled to restart operations after being placed on care and maintenance in 2016 due to depressed nickel prices. The decision to start operations after such a stoppage ought to be led by a techno-economic evaluation of process options to make operations more resilient. For BCL, the decision lies between using the existing flash-smelting furnace (FSF) or a top-submerged lance (TSL) furnace. Available studies show that the FSF combined with other converting technologies is cheaper to operate; however, such studies are based on flowsheet simulation results of single copper concentrates and therefore do not provide a full scope of practical capabilities based on smelter operator skills. Using a t-test on normalized prior operational data from three Cu FSF and two Cu TSL, it was found that the only statistical differences between the operating costs of the FSF and TSL technologies are in the coal use for heating the feed blow and number of rebuilds: the FSF consumes coal to heat the feed blow and the TSL requires 2.4 rebuilds during a course of a single FSF campaign. A summative operating cost comparison over the existing BCL FSF 11-year life shows that BCL can decrease operational costs by some BWP 55.5 million if the operation were to change to the newer TSL technology. The savings derive from reduced coal use, which is normally associated with heating the blow when using the FSF. Despite the TSL carrying added costs of 2.4 rebuilds during a life time of one FSF furnace campaign, the cost associated with the TSL rebuilds of approximately BWP 1.3 million is minimal compared with the overall operational expenditure decrease that BCL will incur on using the TSL technology. In terms of the technology, BCL can have higher Ni–Cu recoveries at lower operational costs by elimination of Ni–Cu losses and eliminating the slag-cleaning furnace by converting to a TSL furnace.

Jul 10, 2024

By Helder Keitaro Arçari Ambo

Aços IF (Interstitial Free) são materiais com grande capacidade de serem conformados a frio, normalmente na forma de chapas, utilizados na indústria automobilística na fabricação de carrocerias de automóveis e outros componentes similares. Neste artigo foi realizado ensaio isotérmico de dupla deformação com objetivo de determinar a fração de amaciamento que ocorre no intervalo entre passes e o parâmetro de amaciamento4. O método para obter estes dados foi utilizando software da Instron em conjunto a maquina de torção e o forno de indução. Os resultados obtidos foram de grande importância no estudo para avaliar o comportamento do material quanto aos fenômenos metalúrgicos e termomecânicos envolvidos, ou seja, se ocorre recuperação, recristalização dinâmica entre outros processos de restauração do material quando submetido a forças externas em elevadas temperaturas.

Oct 30, 2017

By Claudio José Martins da Silva

A planta siderúrgica da TKCSA possui em seu sistema de distribuição de gás dois flares (bleeders) que possuem funções distintas durante o regime normal de operação. O flare 2 é responsável por queimar o gás de alto forno de baixo poder calorífico, gerado no início do processo de partida do alto-forno até que o gás atinja as características adequadas para o aproveitamento e ser direcionado para o gasômetro. Já o flare 1 trabalha em conjunto com o gasômetro no processo de controle de pressão e vazão excedente de gás, quando da redução intempestiva de consumo de gás de alto forno. O presente trabalho apresenta a solução implantada pela TKCSA para garantir, sob quaisquer condições de fornecimento de energia elétrica, a operação dos equipamentos elétricos e de todo o sistema de automação e controle operacional dos flares. Podemos dizer que a operação do flares torna-se autônoma e relação ao sistema elétrico e sistema de automação e controle da distribuição de gás de alto forno. O sistema implantado promoveu uma elevação na segurança operacional dos flares, já que, a autonomia operacional impede o apagamento da chama eliminado a possibilidade de lançamento de gás cru na atmosfera.

Jul 31, 2018

By Jorge Luiz Ribeiro de Oliveira

A indústria siderúrgica na América do Sul tem sido desafiada desde a crise econômica mundial do final de 2008, como as demais siderúrgicas ao redor do mundo. O cenário de continua degradação das matérias primas, em especial o minério de ferro e a necessidade de reduzir custos, considerando que cerca de 70% do mesmo está relacionado à produção de gusa, atuando em direção oposta, torna este desafio maior ainda. Operar um Alto Forno com elevadas taxas de injeção de carvão (mais que 180 kg/t de gusa) e baixo taxa de combustíveis (menor que 490 kg/t de gusa), considerando a elevação da taxa de geração de escória devido a matéria prima em degradação (~300 kg/t de gusa) torna-se obrigatório ter estabilidade operacional por meio de boas práticas operacionais suportado por adequado sistema de manutenção centrado em confiabilidade (RCM). Este trabalho objetiva mostrar como a ArcelorMittal planta de Tubarão está enfrentando esta situação, visando atingir os objetivos citados anteriormente.

Aug 16, 2017

By Júlia Beltrami

O trabalho estudou a formação, a interação com a escória e a solidificação de inclusões geradas durante o processamento de aços dual-phase com alto teor de silício (>1%). A composição destes aços, se não bem controlada, pode gerar inclusões sólidas de sílica pura durante o lingotamento contínuo. Para o estudo, foram feitas simulações termodinâmicas com o software computacional FactSage 6.4. As simulações mostraram que os fatores mais importantes para a composição inicial das inclusões é a relação %Mn/%Si e o teor de alumínio dissolvido no aço. Ao interagir com a escória, a tendência é que as inclusões se aproximem da sua composição ao longo do tempo. Durante a solidificação, a maioria das inclusões apresentou fases deformáveis e de baixo ponto de fusão, com exceção das inclusões sem CaO e da inclusão com 25% de Al2O3 e teor intermediário de CaO, que apresentaram as fases tridimita, coríndon e gehlenita de alto ponto de fusão e não-deformáveis.

Aug 16, 2017

By Juliana Segura Salazar

Algumas estratégias vêm sendo incorporadas na cominuição de minérios, voltadas para reduzir os custos operacionais (OPEX) e garantir o funcionamento de suas operações no longo prazo. Paralelamente, elas permitem reduzir os impactos ambientais desta operação sob a ótica da sustentabilidade, devido às melhorias na eficiência de uso dos recursos e na mitigação das mudanças climáticas. Porém, a incorporação dessas estratégias é restrita pelo tipo de tecnologia empregada e pelo layout da usina e, portanto, o maior potencial de minimização dos impactos econômicos e ambientais encontra-se principalmente na etapa de projeto dos circuitos. Este potencial muitas vezes é desperdiçado, sendo ainda poucas as implementações sistemáticas adotadas na indústria mineral, visando melhorar a ecoeficiência dos processos. Neste trabalho é proposta uma metodologia fundamentada em princípios de sustentabilidade e aplicável ao beneficiamento de minérios, usando uma abordagem simplificada da Avaliação de Ciclo de Vida (ACV). A metodologia é focada na cominuição de minérios brasileiros, tendo sido aplicada ao beneficiamento de Itabiritos, os quais estão se tornando estratégicos no Brasil.

Aug 16, 2017

By Thiago Pinto Silva

Este estudo teve como objetivo investigar o efeito da adição de minérios com diferentes comportamentos a alta temperatura (assimilação e penetração de fase líquida) nos indicadores de processo em uma sinterização piloto. Para isso, seis sinter feeds foram caracterizados e, em seguida, submetidos ao ensaio de sinterização, considerando diferentes misturas a sinterizar. Foi observado que a substituição parcial de um minério que possui grande capacidade de assimilação por aqueles que assimilam pouco o líquido formado no processo de sinterização, resultou em maior resistência mecânica do sínter. Essa propriedade pode também ser associada ao formato dos poros no sínter produto, que reflete na sua redutibilidade. Em termos de penetração de fase líquida, os resultados indicam relação direta com a resistência mecânica do sínter. Dessa forma, esses ensaios de caracterização, juntamente com os aspectos mineralógicos, químicos e granulométricos, permitem subsidiar a tomada de decisão para a substituição mais adequada de um minério na mistura a sinterizar.

Aug 16, 2017

By Mariana Boger Netto

O fósforo é um elemento crítico para a qualidade dos aços, tornando a redução dos teores desse elemento uma exigência para a indústria siderúrgica. Uma forma de se medir a eficiência da desfosforação é através do coeficiente de partição do fósforo (Lp=%P(escória)/%P(aço)). O objetivo principal deste trabalho é avaliar escórias de um forno elétrico a arco através da comparação entre o Lp real com o Lp calculado por simulação termodinâmica, avaliando, também, o comportamento da partição de fósforo com relação à composição química. A partir de dados de composição química de amostras de escória e aço de uma usina siderúrgica, foram feitas simulações termodinâmicas utilizando o software FactSage. Com base nesses resultados, concluiu-se que o cálculo computacional através do software descreve bem o comportamento termodinâmico, mas tende a superestimar o Lp, provavelmente por questões cinéticas e/ou de transferência de massa e calor.

Aug 17, 2017

By Manuel Enrique Rodriguez Blanc

A planta industrial de produção de ferroníquel da Anglo American Barro Alto, localizada no Estado de Goiás, recebeu notificação de clientes como Aperam (Bélgica) e Acerinox (Espanha), em relação ao formato esférico apresentado pelo ferroníquel produzido. Para solucionar o problema, foi realizado teste na planta piloto da empresa de engenharia UHT para desenvolvimento de novos projetos e de nova tecnologia com objetivo de aperfeiçoar o formato do produto final. A utilização de disco de 4 canais solucionou o problema do formato esférico, no entanto, forma-se muito “bodes” ocasionando explosões. O sistema de granulação utilizando um tundish rotativo, mantem as mesmas características físicas do metal granulado com disco de 4 canais além de aumentar a segurança da operação, reduzindo os riscos de segurança do trabalho.

Oct 30, 2017