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By Samuel de Lima Silva

A Comissão Interna de Conservação de Energia (CICE) atuou com uma série de ações para aprimorar a rotina de trabalho com finalidade da redução do consumo específico de gás natural na Unidade de Juiz de Fora da Votorantim Metais Zinco. As principais ações adotadas foram o desligamento de um dos queimadores da Caldeira Aalborg, e regulação do outro para 50%, utilizando o primeiro apenas quando necessário; estudo de melhorias na operação da Planta Polimetálicos, visando a redução de consumo pelo queimador do forno; melhoria no acompanhamento de consumo diário, tanto na chegada de gás quanto na caldeira; levantamento dos pontos de vazamento de vapor e contratação externa para adequação. Como resultado dessa série de ações tomadas, obtivemos uma redução de 17% no consumo específico de gás natural da planta.

Jul 31, 2018

By Agustín Chang Wong

"El presente trabajo señala la aplicación del Planeamiento Estratégico en la Sociedad Minera El Brocal como herramienta conductora empresarial que permite establecer correspondencia entre los problemas identificados y suscausas, los objetivos previstos para superarlos y los planes de acción que se organizan para alcanzar los resultados. El diagnóstico se realizó en el año 2000 y utilizó las siguientes estrategias: reestructuración organizacionalsistemas de gestión, outsourcing, alianza con proveedores y mejoramiento de procesos. De forma, que el mejoramiento sostenido de las operaciones se relaciona con el incremento de la productividad, rentabilidad de la empresa y reducción de costos. "

Jul 31, 2003

By Bill Mariucci, Gary Almeraris

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. 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 individual authors and are not necessarily those of the SME. The mention of trade names for commercial products does not imply the approval or endorsement of SME.

Dec 1, 2009

By T. Field, N. D. Nxumalo

Since the discovery of gold on the Witwatersrand in 1886, mining has been at the centre of South Africa’s development. Although mining continues to contribute significantly to the country’s economy, it is a temporary land-use activity, and mine closure is inevitable. This paper reviews mine closure planning at Tshikondeni coal mine, which commenced in 2014 with the initiation of mine closure. The review presents the mine closure processes undertaken at the Tshikondeni coal mine as regulated by South Africa’s principal mining legislation, the Mineral and Petroleum Resources Development Act 28 of 2002, and other relevant regulatory frameworks. To compile this review: (1) A desktop study was conducted; (2) empirical data was collected through one-on-one interviews with research participants at Tshikondeni coal mine; and 3) physical observations were made of the rehabilitation at various mine operations within the Tshikondeni coal mine complex. Research participants consisted of mine officials from different departments, i.e., human resources, and environmental, social, and business strategy, who were directly involved with the Tshikondeni coal mine closure. A questionnaire with semi-structured questions was developed. It was utilised to acquire a better understanding of mine closure planning at Tshikondeni coal mine and identify mine closure processes that aim to achieve post-mining land uses and align with Tshikondeni coal mine’s post-closure strategy, namely the Tshikondeni Legacy Project, with a post-closure strategy that has the potential to transition a mining economy to an eco-tourism economy that can preserve livelihoods and selfreliant communities.

Dec 15, 2025

By John M. Rogers

Risk management has rapidly developed to become an integrated, holistic approach that now encompasses the main risk elements such as product quality control, occupational health and safety, security, environmental liability, social issues and related management information systems. Given the obvious economic benefits, a seamless blend of risk management components has become essential to allowing organisations to sustain a competitive advantage, and is also looked upon as an important attribute in organisational growth. Juxtaposed with this management philosophy is the global trend towards outsourcing, which has seen the emergence of independent, and specialist risk management organisations. The New Millennium will undoubtedly see a shift away from "in-house" risk management practices, and consequently, the selection of a suitable risk management partner - a major vehicle for improving shareholder value - will become an important strategic management decision.

Jan 1, 1999

By C. Frenzel, N. Blechschmidt

"INTRODUCTION There is no doubt about the time and effort companies put in establishing and maintaining their equipment. However, the question about how these companies can map the benefits comes up. Neither do they have the tools to quantify the benefit of their action, nor do they have the tools to know the actual quality of their current maintenance system. The resources used in the process seem futile to observers. It seems impossible to trace improvements and to get information about the impact of actions in retrospect. Improvements in maintenance performance cannot be recognised by management or shareholders. Thus the necessity for measuring the performance of maintenance systems is given. In this paper ConMoto is systematically showing the strengths and weaknesses of many companies' maintenance management and is providing field-tested proven design elements for measuring maintenance systems and implementing Value Oriented Maintenance. Considering only business assets in production facilities and related machinery out of all investment goods in Europe, you reach a value of around 9.7 trillion euros in 2008. In Germany alone the equipment replacement value amounted to about 1.9 trillion euros [8,10,11,13]. If you calculate a cross sector maintenance costs rate of 4.8 % (corresponding to the average value identified in this study), direct maintenance costs in European production locations add up to over 450 billion euros per year [3]. These figures speak for themselves. Yet maintenance is not only of enormous significance for European enterprises. Our experiences show that maintenance and asset management, particularly sustainability issues, are also increasingly moving to the forefront in the BRIC states, in the Middle East and in many emerging countries. First of all, in order to meet the resulting high quality and cost related requirements of maintenance systems, a comprehensive overview of the issue is needed. This overview is provided by a detailed analysis of 83 companies and production plants from various sectors – with amazing results. SIGNIFICANCE OF MAINTENANCE Current studies show the high financial significance of maintenance and asset management. According to the market study in the Asset Manager [9], in industrialised countries about 10 to 15 per cent of the labour force are employed in maintenance and facility management tasks. In Europe about 40 to50 million people are directly and indirectly involved in retaining the value of machinery, plants, buildings, transport systems and infrastructure facilities. A glance at the costs side also demonstrates the great relevance of maintenance. EU-wide annual direct maintenance costs amount to a total of more than 1,500 billion euros. In Germany alone they are about 250 billion euros. This impressive total is considerably exceeded by indirect maintenance costs caused by technical failures. Indirect costs are estimated to be five times higher (Figure 1). [7,12,14]"

Jan 1, 2018

This paper details a brief history of the Australian gold industry from the 1980s gold boom to the present day, highlighting an industry characterised by innovation in plant design and junior companies prepared to "have a go", in contrast to the conservatism of many larger mining companies. Design flexibility, the innovation of new processes, the preparedness to exchange "process know how" and technology singularly differentiated the gold industry from other sectors during the 1980s to the present. The introduction of two stage crushing, semi autogenous (SAG) milling, and pebble crushing, mill innovations, carbon in pulp (CIP) and carbon in leach (CIL) and the North Kalgoorlie screen etc were all exciting changes in the industry.

Jan 1, 2011

By André Luis Martins de Souza

O objetivo do estudo foi medir e aumentar a produtividade das equipes de manutenção - em uma mineradora multinacional - dentro e fora das paradas de manutenção, avaliando os principais fatores que influenciam o indicador e, ainda, reduzir os custos de manutenção referente a contratação de efetivo terceirizado através da inovadora metodologia Six Sigma, para este trabalho utilizou-se um metodo quantitativo, analítico e experimental. Após a finalização do projeto obteve-se o aumento da produtividade da equipe de manutenção em todos os turnos analisados e os custos foram reduzidos em aproximadamente R$ 200.000,00 e o tempo para resolver pendências que era de 50,1 dias foi reduzido para 18,1 dias.

Oct 30, 2017

By M G. Shaw, M A. Rhamdhani, S P. Singh, A R. Duffy, B Eisenbart, A K. Shukla, G A. Brooks

The field of astrometallurgy is a growing area of study. Metal production on the Moon is likely to begin in less than a decade as major space agencies such as NASA (National Aeronautics and Space Administration) and CNSA (China National Space Administration) are preparing to construct permanent lunar bases. The utilisation of regolith to generate oxygen and metals is expected to be important in the development of a sustainable lunar habitat. This paper provides an overview of potential metallurgical processing methods for lunar conditions, emphasising the impact of lunar factors on slag chemistry. The interaction between regolith and the extracted metals, as well as their impact on slag composition and refractory performance, are critical considerations in metal production on the lunar surface. The initial research on lunar metallurgical technologies is focused on oxygen extraction and Fe-Si alloys are reported as the by-products of these processes. This paper delves into the fundamental thermodynamics associated with the carbothermic reduction of lunar regolith. Thermodynamic analysis using the FactSage™ ver 8.2 software package indicates that the Fe-Si alloy can be produced as a metallic product from the lunar regolith at temperatures ranging from 1400°C to 1600°C under terrestrial conditions. However, under ultra-high vacuum conditions (3 × 10-15 bar) on the Moon, the required operating temperature for producing ferrosilicon would be significantly reduced. Thermodynamic modelling results indicate that under lunar vacuum conditions, Fe-Si alloys only exist as solid phases at lower temperatures below 650°C. At higher temperatures, both Fe and Si are expected to be present in the gas phase. In this work, the carbothermic reduction of the Lunar Mare Simulant (LMS-1) is conducted under terrestrial conditions. The findings indicate that the process can readily yield Fe-Si alloys with 7–10 wt per cent Si at 1600°C. Additionally, energy dispersive spectroscopy (EDS) analysis of the resulting Fe-Si alloy indicates the presence of phosphorus up to 1 wt per cent.

Aug 21, 2024

By Semih Perdahcioglu, Arthur E. Morris

"The curricula for the majority of Materials Science and Engineering programs is devoid of all but the most rudimentary coverage of the principles of material and energy balance calculations. As a result, graduated engineers that need to make such calculations are faced with three unpalatable options. First, attempt to learn the subject by attending workshops or short courses sponsored by corporations or industry groups. Second, outsource the needed work to a consulting engineering company. Third, purchase a software package that's capable of simulating a process. Each of these options require a considerable investment of employee time and effort. The first option might be the best if suitable computational software was readily available. We review the recent development of such software, which is entirely based in Excel. The software tools include a thermodynamic database, tools for multiple computations, and a flowsheet simulation program. These tools employ teaching by simulation.IntroductionPracticing engineers often come up with situations where they must learn a technical subject that they didn't cover in their college classes. One possibility is to obtain a couple of texts on the subject, and delve in. Or, they may sign up for an intensive short course where they can get personal instruction and guidance. But the first option requires a lot of study time, and the second option may not provide the specific instruction (or intensity of instruction) required to appropriately master the subject. Here we look at ways of using simulation techniques to learn the methodology for making material and energy balances on industrial processes.Industrial heating processes have undergone many changes over the past dozen years, as vendors have introduced new heating equipment designed to recover the greatest possible amount of heat from the fuel, and to meet stringent environmental challenges for emissions (especially NOx). Even though the recent unprecedented drop in price of natural gas may have altered the urgency for improving a plant's energy efficiency, the need is still there. Until recently, there was a dearth of readily-available software for process engineers to use for simulating a plant's flowsheet. The good news now is the existence of several Excel-based software tools that make the calculational process much easier. [ 1]. Plant engineers may also be interested in a DOEsponsored program[2] which allows plant-wide and ""what-if' analyses of the energy balance."

Jan 1, 2013

Much has been published in recent years on the challenges facing the engineer of the 21st century and the consequent challenges facing the education providers and industry. The world is changing rapidly on the social, economic, political, technical and environmental fronts and our metallurgists/mineral processing engineers of the future will arguably need to have a different set of skills than those which were traditionally regarded as adequate during the latter half of the 20th century. This paper attempts to explore some of these issues and their ramifications.

Jan 1, 2014

The STATE MINERAL SUMMARIES publication provides estimated data and summaries of mineral activities at the State level for 1993. Most of the estimates are based on nine months data. Individual State summaries are published separately as State Mineral Industry Surveys and copies can be obtained from the appropriate State mineral officer. In an effort to facilitate the rapid dissemination of information and publications produced by the U.S. Bureau of Mine, an electronic document dissemination system is now available for use. MINES FaxBack is a simple-to-operate automated fax response system that operates 24 hours a day, seven days a week. All a user needs is access to a fax machine with a touch-tone telephone. MINES FaxBack can be accessed by calling (412) 892-4088, using the touch-tone telephone attached to the user's fax machine. After calling MINES FaxBack, the requester is guided by a series of voice messages to assist in ordering the desired documents.

Jan 1, 1994

By Christian Heili

In 1991 the Government of the Republic of Zambia passed legislation providing for the privatisation of Zambia Consolidated Copper Mines Limited (ZCCM). The newly formed Mining Companies, established after nearly a decade of difficult and protracted negotiations on such matters as, cash at close; retained percentage interest by ZCCM; equity investment; future investment commitment and tax concessions, were faced with great internal challenges and a harsh external environment. There was a convergence of a number of negative forces that had and will continue to have an impact on the mining environment in Zambia. The most crucial of these being, the competitive pressures of the global economy, fluctuating copper price and the prevailing HIV/AIDS pandemic. In the short period after privatisation, the Industry has seen the collapse of Binani Industries (Luanshya Mine), the withdrawal of Anglo America Corporation from Konkola Copper Mines Plc and the disposal of Chambishi Cobalt and Acid Plants by Anglovaal Mining Ltd. The objective of this paper is to provide a theoretical and practically researched foundation, which may be used to assist Zambian Mining Companies in making informed decisions on the issue of Strategic Outsourcing and the degree to which this may support the successful and sustainable growth of the Zambian Copper Mining Industry. If judiciously implemented, Strategic Outsourcing has the potential to generate a practical business valuation and process to assist Mine Management in the achievement of their business goals and consequently the return on investment to their Shareholders.

Jan 1, 2005

By Cary Hirner, Dan Lopez, Ross Webb, Stephen O’Connell

"Construction of the largest desalinization plant in the Americas has commenced in northern Chile. It is part of a several billion dollar expansion at a copper mine whose operations nearly stopped due to the challenge of securing a reliable source of water from the Pacific Ocean in a safe and environmentally sound manner. This paper discusses the risk management, design and construction of a quadruple chamber intake and outfall shaft, high capacity pump station, three 7m diameter vertically drilled marine shafts and three subsea tunnels constructed through challenging Andean hard-rock geology. The three 2.5m diameter subsea microtunnels are being mined with vertical curves through variable quality rock 30 meters beneath the ocean and retrieved in the wet from the 7m diameter marine shafts. INTRODUCTION AND BACKGROUND The battle for securing the rights to a constant water supply is a worldwide issue and nowhere is that more evident than the Atacama Desert of Chile, the world’s driest place with areas of the desert that have not seen rainfall in recorded history. The Atacama Desert also happens to be home to some of the world’s largest ore deposits which require huge amounts of water to extract and process. What available water there is comes from three main sources: deep seated wells, glacial water from the Andes Mountains, and desalinated water. Vying for water from wells and glacial streams and lakes are numerous agricultural and domestic facilities in the valleys surrounding the Atacama Desert. Environmental regulations and legal rulings have limited the amount of “natural” source water which can be used for mining purposes. Desalination plants are a known solution for combating water scarcity, albeit a costly one. The total estimated cost of constructing this desalination plant is over $3B USD, which will include a 2500lps capacity and an approximately 118km pipeline from the coast up to the mine located in the Andes. The overall scope of the project includes design, procurement, and construction packages for the 2500lps desalination plant including the seawater reverse osmosis plant, water conveyance to the mine, power transmission, the reservoir and the marine works package which forms the basis of this paper. Key components of the underground construction portion of the Marine Works are:"

Jan 1, 2016

By Manish Kumar Jain

The mineral industry in India is an important contributor to the country?s GDP and foreign trade, and also a significant source of employment generation. The industry is distributed almost all across the country and has operations in some of the remotest areas, where it has also served as a sole source of infrastructure development. India produces 89 minerals, out of which four are fuel minerals, 11 metallic, 52 non-metallic and 22 minor minerals. The mining leases are occupying about 0.21% of the total land mass of the country. Indian mining industry is characterized by a large number of small operational mines (approx 3000 mines). Appropriate systems have been put in place to ensure sustainable growth of the sector, which include formulation of procedures for scientific prospecting and mining and development of a mechanism of prior environmental and forest clearances for mining projects. Main emphasis is to protect the health and safety of mine workers, as well as to safeguard the interests of indigenous people through rehabilitation and resettlement packages. Efforts are under way to mainstream the artisanal and small-scale mining sector in order to promote equity in the mining industry. The issue of scientific closure and reclamation of the abandoned mine sites poses a major challenge. Present paper illustrated several initiatives have been taken in this direction along with case studies, which could be replicated in other parts of the country.

Aug 1, 2013

By J Kwak

Driving sustainability concepts and practices into the heart of the design process is the key to achieving a successful, sustainable plant design. Engineering design practices, tools, systems and methodologies should be prepared around true eco-efficiency parameters, adopt wholesystems-thinking and consider life-cycle impacts for the design task. Experience dictates that the application of sustainable plant design practices is most likely to succeed if: The principles are well documented and explained. All stakeholders agree on what sustainability means. Sustainable plant design is treated as a core process. The principals of sustainable plant design are equally applicable in brownfield and Greenfield environments. Although brownfield situations provide the designer with less latitude for change, these types of projects do allow easier measurement and demonstration of relative impacts. This paper further develops the above points by drawing on case studies from HatchÆs repertoire.

Jan 1, 2004

By Aidan Giblett, Karen McCaffery, Robert Dunne

"A worldwide decline in competency levels of practicing metallurgists over recent decades has become clearly evident and is a common topic of discussion among senior practitioners and professional associations. The associated impacts on the industry are material and include operational inefficiencies, missed optimisation opportunities and suboptimal new plant designs. There are many contributing factors to this condition. Decrease in competency is particularly evident both in regions where imbalance between supply and demand has led to a general reduction in experience levels for comparable roles over time and in emerging regions where a rapid rise in demand for practitioners has occurred in conjunction with rapid economic development and industrialization. The context, depth and breadth of education curricula and levels vary with location such that solutions to the technical competency dilemma may need to be developed specifically for each region with these influences in mind. Delivering, demonstrating and maintaining competencies are a critical requirement of undergraduate training and ongoing professional development. Other factors such as generational and cultural characteristics and expectations, political influences, role requirements and employment reward and recognition systems all play a critical role in determining if core competencies can be effectively developed, applied and subsequently maintained. This paper reviews factors impacting and some common approaches to competency development. The authors’ experiences in the management of professional development efforts within the global industry are reviewed and a blueprint proposed to address industry requirements in this area."

Jan 1, 2014

By V. N. Kazakidis

With increased levels of automation, capitalization, and empowerment of citizens, the traditional axis of labour versus capital or national government versus capital, upon which the allocation of benefits from a mining project was traditionally based, has shifted primarily to a capital versus community axis. In light of this paradigm shift, it is critical for the sustainability of mining that economic indicators be considered at the pre-feasibility, feasibility, and permitting stages of a project. Such indicators should emphasize the ?ripple effect? of the economic impact of a capital-intensive mining investment on a region due to outsourcing, as well as the diversified spin-off opportunities and the technological advances that can be exploited by local communities.

Jan 1, 2003

By J. Hendry, K. Brady, J. Yorzyk

Drawing from the experience of nickel, copper, aluminum and mineral borates, this paper illustrates the business value that the mining, minerals and metals industry as a whole can gain from applying life cycle assessment (LCA) to products and operations. Through the use of case studies, the paper explores how companies and industry associations have used LCA to their advantage: from evaluating capital investments, meeting customer information needs, supporting new product applications, and developing credible marketing information on the environmental performance of their products. It also explores the dynamics of LCA adoption and integration within companies, and provides recommendations to further strengthen institutionalization of LCA.

Jan 1, 2010

By Theodore M. Katz, W. Stephen Brightwell, David E. LeGrande, Joseph J. Hurrell, Jane A. Lipscomb, Nancy Lessin, Lawrence R. Murphy, Michael J. Colligan, Steven L. Sauter, Richard A. Lippin

Revolutionary changes in the organization of work have far outpaced our knowledge about the implications of these changes for the quality of working life and for safety and health on the job. This gap in knowledge is one of the 21 priority areas for research under the National Occupational Research Agenda (NORA)—a framework crafted by the National Institute for Occupational Safety and Health (NIOSH) and its partners to guide research into the next decade. This report was developed under NORA as the first attempt to develop a comprehensive research agenda for investigating and reducing occupational safety and health risks associated with the changing organization of work. Research and development needs identified in the agenda include (1) improved surveillance mechanisms to better track how the organization of work is changing, (2) accelerated research on safety and health implications of the changing organization of work, (3) increased research focus on organizational interventions to protect safety and health, and (4) steps to formalize and nurture organization of work as a distinctive field in occupational safety and health.

Jan 4, 2002