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By Paul Swatkowski

A Note About Copyrighted Material ??Permission to Use? has been granted ?Teachthe7habits ?Think win/win (4thHabit) ?Don?t stop here ?i.e., buy the book

Jan 1, 2009

By Akira Tsune, Shingo Sugimoto, Tadayuki Ishiyama, Nadao Saito, Masatsugu Okazaki

"The Deep Ocean Resources Development Co. Ltd. (DORD) of Japan signed a 15-years contract with the International Seabed Authority for exploration of polymetallic nodule in a 75,000 km2 area, consisting of West and East Areas in the Clarion and Clipperton Fracture Zone in 2001. The exploration work is now concentrated in resource estimation of the first generation of mining area, the High Abundance Area.A detail survey of the Model Area, set in the High Abundance Area, was conducted using AUV (Autonomous Underwater Vehicle) equipped with MBES (Multi-Beam Echo Sounder), SSS (Side Scan Sonar), Sub-Bottom Profiler (SBP) and still camera. The seafloor topographic map based on 1 m grid data was produced in an area of approximately 80 km2 (Figure 1). Photographs, continuously covering the seafloor taken by AUV along two west-east trending traverse lines, together with detail seafloor topographic map produced from MBES give an excellent opportunity to observe distribution manner of pollymetalic nodule related to topographic features. This helps to understand more accurate resources estimation of a whole area of the High abundance Area. Furthermore, information of micro-topography gives ideas for conducting ore collecting operation and designing ore collector."

Sep 1, 2014

By S. Ndlovu, M. Malatse

"The Witwatersrand Basin is the heart of South Africa’a gold mining industry. The cluster of gold mines located in the Witwatersrand Basin generates a significant amount of mine tailings, which have adverse effects on the environment and ecological systems. In addition, disposal costs are very high. The exponential population growth in the Witwatersrand area has resulted in pressure on the reserves of traditional building materials. Quarrying for natural construction material is very expensive and damages the landscape. This work therefore examines the use of gold mine tailings in the production of bricks.Different mixing ratios of gold tailings, cement, and water were used. The resulting bricks were then cured in three different environments - sun dried, oven dried at 360°C, and cured in water for 24 hours. The bricks were then tested for unconfined compressive strength, water absorption, and weight loss. The results showed that the mixture with more cement than tailings had a compressive strength of approximately 530 kN/m2. It was also found that the best brick curing system was in a water environment. Bricks made from tailings cost more than conventional bricks because of the higher quantity of cement used, but the manufacturing process consumes less water. Overall, the results indicated that gold mine tailings have a high potential to substitute for the natural materials currently used in brickmaking.Paper written on project work carried out in partial fulfilment of BSc. Eng. (Metallurgyand Materials Sciences)"

Jan 1, 2015

By César Arce

El presente texto establece una plataforma de comunicación oficial entre la empresa y sus socios estratégicos logrando la estandarización del comportamiento empresarial y humano en temas relacionados con medio ambiente, salud, seguridad, relaciones con las comunidades, recursos humanos y la legislación vigente. En este sentido, las empresas que trabajan en forma directa o indirecta para el titular, impactarán directamente en los resultados y reputación del mismo, sino mantienen una visión, objetivos y comportamientos similares

Sep 9, 2007

Sustainable development is a critical discussion topic in the mining industry today. The topic is necessarily broad and complex, covering an entire spectrum of related areas, from geology to end-use products. The objective of this keynote address is to focus on the chemicals and chemistry aspects - especially research and technology transfer - in sustainable mineral processing. Chemicals came to play a critical role in mineral processing during the last century, and they will play an equally vital role in confronting the sustainability challenges of the 21st century, particularly in the areas of greener chemicals, water efficiency and water resource management; waste reduction and remediation; minimising environmental impact, safety and health risks (meeting and exceeding the requirements of regulations); energy efficiency; and converting mineral resources into reserves. This keynote address argues that the current research framework is no longer adequate to serve the goals of sustainable mineral processing. The problems studied are often too narrowly defined or irrelevant, while the research efforts are fragmented and the methods and approach employed are often too reductionistic to produce useful knowledge. A new framework for research is needed. This address further argues that a new framework based on a holistic or systems approach can best tackle the challenges of sustainable mineral processing. Central tenets of this approach include a recognition that, in complex systems, the behaviour of the whole system is more than the sum of the individual contributions, and that interactions occur in real time, often in subtle and complex ways. The focus is thus on the behaviour of the whole system. Indeed, a comprehensive understanding of the system through large-scale measurements should precede a study of parts or of idealised models of the complex system. The result will be a sound knowledgebase, better solutions to the challenges of sustainable development, and improved technology transfer. Developing such a framework will pose a formidable challenge, requiring significant time and effort as well as a confluence of diverse specialties and strategic collaboration. Fortunately, recent developments in the context of reagent optimisation provide us with a prototype of a holistic approach. We can also draw upon methodological innovations in the biological sciences, where the critical need for a systems approach is well recognised and significant advances have been made.

Sep 13, 2010

By Pedro Condori

Usualmente, la minera Atacocha está expuesta a grandes precipitaciones pluviales durante una larga temporada húmeda. Por lo que es necesario eliminar gran parte del agua colectada por las lluvias a través de las plantas de tratamiento de aguas de exceso que garanticen los contenidos metálicos por debajo de los limites máximos permisibles. En ese sentido, el presente texto describe la aplicación de un modelo matemático para comprender, manejar y optimizar las diferentes variables que afectan al proceso del tratamiento. El modelo está basado en los fenómenos de transporte de solución a través de la pila y la cinética de cianuración de los metales contenidos en el mineral, el cual permitirá simular los cambios en los parámetros operacionales y metalúrgicos como diferentes tipos de mineral, flujos entre plantas Merrill Crowe y CIC, un mejor tratamiento de excesos de agua para minimizar su efecto en la producción de oro y el manejo óptimo de soluciones y predicciones a futuro de producción de oro.

Sep 9, 2007

By Peter Swanson

One of the primary methods for analyzing roof stability in underground mines is the age-old method of “roof sounding” where a miner taps on the roof and listens for the hollow sound of loose blocks of rock. This paper looks at the feasibility of using noncontact laser-based vibration measurements to detect roof fall hazards with the ultimate vision of improving, expanding and automating procedures for mine roof inspection. Vibration measurements made on loose blocks of rock in underground mines are summarized and compared to estimates of fundamental resonance frequencies for rock slabs of the size responsible for highly hazardous “skin failures.” Both laser Doppler vibrometry and full-field interferometric methods are examined and are considered to be feasible methods for detecting anomalous vibrations in loose roof rocks. Results from simple laboratory experiments using laser vibrometry demonstrate some of the proposed application concepts. While considered a challenge to move these techniques from the laboratory to heavy industrial or outdoor environments, the potential for success in the current application is enhanced by the reduced requirements of qualitative analyses.

By Anthony T. Iannacchione

The Roof Fall Risk Index (RFRI) is a new method introduced by the National Institute for Occupational Safety and Health (NIOSH) to assist the underground stone mine operator in 1) assessing defects the mine strata and 2) rating the relative roof fall risk these defects pose. The RFRI utilizes observational techniques to identify defects in the roof strata caused by local geologic, stress, and mining conditions. Assessment values for ten defined defect categories provides the foundation for estimating a range of risk conditions between 0 and 100 that define the potential for a roof fall. This paper examines how the defect information is collected using two field verification sites and proposes methods to analyze the RFRI data. These examples provide information on how well the method replicates observed conditions and how it might be applied in practice.

Jan 1, 2006

By Glenn Clarke, Ben Holloway, Barry Lumsden

"BHP-Billiton’s Cannington mine in Northwest Queensland produces a silver-rich lead concentrate and a zinc concentrate. The plant has the capacity to treat 3.1 mta and for the year to June 2006 mean feed grade was 10.3% Pb, 461 g/t Ag and 3.7% Zn. Recovery losses of lead and silver are primarily in the fine fractions. In 2001, the plant was modified when it was determined that splitting the lead feed into two size fractions, and floating the two fractions separately increased fine lead and silver recovery. The fine lead fraction (called the split float) is 80% <16µm and about a quarter of the lead and silver is in the finest fractions. In 2006 to further improve lead and silver recovery a statistical plant trial of magnetic aggregation conditioning of the split float feed was undertaken. While pure galena is diamagnetic the Cannington galena contains iron within the galena mineral resulting in the galena having a paramagnetic, magnetic susceptibility. The trial demonstrated to greater than 98% statistical significance an increase in lead recovery, and to 99% statistical significance an increase in silver recovery, and to greater than 97% significance an increase in the lead in concentrate in the split float circuit. These economic recovery benefits with magnetic aggregation of the split float feed, has led to the incorporation of this technology in the plant.INTRODUCTIONThe BHP-Billiton owned Cannington silver, lead and zinc mine is located in the Australian state of Queensland about 800 kilometres west of the coastal city of Townsville. This is a pastoral area characterised by large cattle farms, low population density and very little infrastructure. The area has two seasons, a wet, hot summer and a dry, mild winter. Because of its isolation and lack of infrastructure the mine has always operated on a fly in fly out basis.Geological drilling defined the resource as 43.8 million tonnes grading 11.6% lead, 4.4% zinc and 538 ppm silver (Walters and Bailey, 1998). At times during its history Cannington has held the crown as the single largest lead and silver mine in the world (Torrisi and Smith 2003). Another unique characteristic of the operation’s history is the rapid progress from discovery to operation. The first drill to intersect the ore body was in 1990 and the mine and plant was commissioned in 1997."

Jan 1, 2008

By Allen Chung, John Twomey, Christopher J. Greet

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

Jan 1, 2011

By P Gunn, M Watts

The general goal of passive acid mine drainage (AMD) treatment is to reduce levels of acidity and metals to acceptable levels. Most treatment systems use either an oxidising or a reducing strategy. In oxidising systems, alkalinity is added along with dissolved oxygen; in reducing systems, dissolved oxygen is removed (if present) and then alkalinity is added. It is recommended that small-scale field trials be conducted as part of the methodology of selecting the best remediation strategy at AMD sites. Following successful field trials at the Sullivan Mine AMD, the Pike River Coal Company (PRCC) has shown foresight by using the same system to treat AMD generated as a result of taking a bulk sample of coal at the Pike River coal field. The system reduced acidity by 100 per cent, iron by 99 per cent, aluminium by 96 per cent, nickel by 95 per cent, manganese by 51 per cent and zinc by 99 per cent. The success of this field trial suggests that a system using a reducing strategy may be appropriate for the Pike River Adit AMD site.

Jan 1, 2005

By Dave Minney

The South African mines health and safety regulations require that mine management establish a quality management system for rock support material. Quality control of resin capsules used as a support medium in South Africa is specified under SA National Standards No 1534. Experience has shown that this specification, while addressing the chemical and physical aspects of the products, but does not address the required performance criteria. In order to address this shortcoming, the industry has put a lot of emphasis on short encapsulation pull tests, performed insitu, in the underground workings of the mine. This is also fraught with many shortcomings, particularly as regards site availability, cost and repeatability of results. To try and address these issues, the Department of Mechanical and Aeronautical Engineering at Pretoria University were approached to develop equipment and machinery that could produce reliable, repeatable results in a laboratory environment which reasonably simulates installation practice underground. The test method is based on the ASTM F432-95 Strength Index test, but modified to use push test rather than pull tests. The paper describes development of the test method and the preliminary results and findings of the work.

Jan 1, 2007

Computation is believed to be a powerful tool in scaling-up chemical processes and in designing materials, however, is being challenged by low predictability and limited scalability. This presentation will discuss the promising future of multi-scale computation in solving these two problems to realise the real-time simulation of industrial processes. Multi-scale structures are a common nature of most chemical systems and the meso-scale phenomena are believed to be the road blocks not only in improving the predictability of physical modeling but also in extending the scalability of computation. Focusing on the meso-scale phenomena, a series of research has been carried out at the Institute of Process Engineering, Chinese Academy of Sciences, for the past three decades. Starting with a simple idea of modeling the meso-scale clusters in gas-solid two phase flows, the so-called EMMS (Energy-Minimisation Multi-Scale) model was established. In verifying the stability condition of the model, the pseudo-particle approach was proposed to explore the micro-mechanisms in particle-fluid systems, and the strategy of the EMMS model was extended to other six different multi-phase systems, resulting in a unified conceptual formulation of multi-phase complex systems expressed by a multi-objective variational problem. In applying this model to different multi-phase systems and to industrial problems, it was recognised that the EMMS model defined a new paradigm of multi-scale computation by realising the structural similarity between software, hardware and the problems to be computed. This paradigm of computation was implemented on a multi-scale supercomputer with a capacity of 1.0 petaflops by integrating CPUs and GPUs (Graphic Processing Units), showing high efficiency and low cost. Running the EMMS model on this computer, the simulation of hydrodynamics of multi-phase systems can be speeded up very much, indicating a promising future of virtual reality of process engineering. The presentation will review this series of work, introduce successful applications in industries, and will be concluded by emphasising the critical importance of the meso-scale phenomena as the bridge between macro-dominants and micro-mechanisms. This is an ABSTRACT ONLY. No full paper was prepared for this presentation.

Sep 13, 2010

By Marina Carreiro-Silva, Cátia Cardoso, Bruce Shillito, Lisa Mevenkamp, Alastair Brown, Maria J. Bebianno, Juliette Ravaux, Inês Martins, Nélia C. Mestre, S. Sousa Vânia

Mineral extraction activities in the deep sea will expose the local fauna to potentially toxic compounds. However, very few data are currently available on the complex ecotoxicological risks to deep-sea fauna from the potential release of heavy metals, trace metals and Rare Earth Elements (REEs). Nonetheless, this is key information essential to support the regulation of industrial activities in the deep sea. One of the fundamental issues that the MIDAS project will address consists in exploring the concept of whether the existing toxicity test protocols and limits established in shallow-water species are applicable to deep-sea mining. We will detail the specific challenges to recommending exposure limits within the deep sea and show preliminary results of comparative toxicity tests in the shallow-water and in the deep-sea environment.

Sep 1, 2014

By R. Guimarães, L. Silva, J. Milboume

The São Bento concentrator was built by Gencor in 1985 to treat refractory gold-bearing flotation concentrate. The plant was the first commercial application of pressure oxidation for refractory gold ore following about a year after the first use of pressure oxidation on a whole ore at Homestake&apos;s McLaughlin operation in California. Ore from the Sao Bento mine is remarkably consistent in gold grade and arsenic and sulphide concentration as is typical in banded iron formations (BIF) (l). Gold content is approximately 9 g/t with approximately 30 - 40% free milling. The balance is associated with arsenopyrite and pyrrhotite. An expansion of both process facility and mine was undertaken between 1996 and 1998, raising the treatment capacity from 32,000 t/mo to 45,000 t/mo.

Jan 1, 2004

By Minghao Hu, Hongbo Zhao, Jun Wang, Wenqing Qin, Rui Liao, Central South University

"In the present work, X-ray diffraction (XRD) analysis, X-ray photoelectron spectroscopy (XPS) analysis and electrochemical analysis were carried out to investigate the intermediate species and electrochemical dissolution process of chalcopyrite in the presence of sulfur and iron oxidizing microorganisms. For bioleaching of chalcopyrite by the sulfur oxidizing microorganism Acidithiobacillus caldus, the redox potential was always lower than the appropriate value and chalcopyrite was mainly directly oxidized to polysulfide (Sn 2-), thus resulting in low copper extraction. As for bioleaching of chalcopyrite by the iron oxidizing microorganism Leptospirillum ferriphilum, chalcopyrite was mainly directly oxidized to polysulfide at the initial stage where redox potential was lower than the appropriate value and resulted in low dissolution rate. At the middle stage where redox potential was appropriate (about 350–480 mV vs. Ag/AgCl), chalcopyrite was mainly transformed to intermediate species of Cu2S rather than polysulfide, thus resulting in high dissolution rate. At the later stage where redox potential was higher than the appropriate value, chalcopyrite was mainly directly oxidized to polysulfide which caused the later passivation of chalcopyrite. Finally, a model of electrochemical dissolution process of chalcopyrite in the presence of sulfur and iron oxidizing microorganisms was provided.INTRODUCTIONBiohydrometallurgy is considered as one promising mineral processing technique in processing low grade ores due to the advantages of simplicity, low cost and eco-friendly. Chalcopyrite (CuFeS2) is the most abundant copper-bearing resource, accounting for appropriately 70% of the known reserves in the world, while is recalcitrant to bio-hydrometallurgy mainly due to the coated passivation layer (Klauber, 2008; Li, Kawashima, Li, Chandra, & Gerson, 2013). However, the detailed dissolution and passivation mechanisms of chalcopyrite bioleaching are still uncertain. The microorganisms assisting chalcopyrite dissolution can be mainly classified into three types, including mesophilic microorganisms (e.g., Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans and Leptospirillum ferrooxidans), moderately thermophilic microorganisms (e.g., Acidithiobacillus caldus, Sulfobacillus thermosulfidooxidans and Leptospirillum ferriphilum), and extremely thermophilic microorganisms (e.g., Metallosphaera sedula, Sulfolobus sp., Acidianus sp., and Sulfurcoccus mirabilis). Moderately thermophilic microorganisms have a better prospect in the future industrial application of chalcopyrite bio-hydrometallurgy (Olson, Brierley, & Brierley, 2003; Rohwerder, Gehrke, Kinzler, & Sand, 2003). Hence, investigating the detailed dissolution and passivation mechanisms of chalcopyrite bioleaching by moderately thermophilic microorganisms is of important significance, which will provide essential information for promoting chalcopyrite bioleaching by moderately thermophilic microorganisms in laboratory or industrial plant."

Jan 1, 2016

By L. W. Beckstead

The use of acid ferric sulfate solution as a lixiviant for chalcopyrite concentrates has been of little interest from a practical standpoint due to the formation of a tenacious layer of elemental sulfur which severely impedes the reaction progress. CuFeS2 + 4Fe+3 ?Cu+2 + 5Fe+2 +2s° For example, an acid ferric sulfate leach of chalcopyrite concentrate results in only 12% copper extraction in a three hour leach at 93°C. Experimental results suggest that particle size is the only controllable variable which has a significant effect on the rate of acid ferric sulfate leaching at ambient pressure. Size reduction of the concentrate prior to leaching was exam¬ined using various methods of grinding. Of the grinding methods considered, attrition grinding was found to be the most effective. Leaching of an attritor-ground product (median particle size 0.5 microns) resulted in approximately 90% copper extraction in a three hour leach at 93°C. Energy measurements suggest that the costs associated with attrition mill¬ing are not unreasonable. Evidence indicates that "activation" or stored strain energy is not responsibile for the enhanced reaction kinetics of the finely ground concentrate, but rather the experimental results can be explained simply in terms of the increased surface area due to size reduction. Leaching reaction mech¬anisms operative in the acid ferric sulfate system are discussed and the application of ultra-fine grinding technology to other systems is considered.

Jan 1, 1976

By Albert H. Clough

The West Lynn Canal subarea of the Juneau Mining District (JMD) is defined by Lynn Canal on the east, Davidson Glacier to the north, Icy Strait to the south and the Glacier Bay National Park Boundary to the west (figs. C-l and C-2). This area extends along the main-land west of Juneau (across Lynn Canal) northerly, to approximately 20 miles south of the city of Haines. The only roads in the area are relatively new logging roads at the southern end constructed to support a U.S. Forest Service timber sale. There is also local road access near the community of Excursion Inlet. Access to the remainder of the region is either by boat, aircraft, or &apos;foot. Helicopters provide the only time effective access to all but the coastal parts of the West Lynn Canal subarea. Coastal areas may be reached by small boat or float aircraft. There is an unimproved dirt airstrip just north of the mouth of the Endicott River. This airstrip is suitable for use by light aircraft. The subarea lies within the Tongass National Forest and is managed by the Department of Agriculture, U.S. Forest Service. Approximately two-thirds of the forest lands are open to mineral entry under the current Tongass Land Management plan. The remaining forest lands comprise the Endicott River Wilderness area, which is closed to mineral entry. Private lands within the study area are sparse, with scattered homestead tracts along the coastal regions and in the Excursion Inlet area. Sealaska (Southeast Alaska Regional Native Corporation) also has land selections in the southern Chilkat Range. Tidal and submerged lands are owned by the State of Alaska.

Jan 1, 2012

By Gene R. Reid

The contract objective is the development and in mine testing of an Automatic Fire Control System (AFCS) for mobile underground metal mining equipment. The effort described by this report covers the period from June 21,1975 through June 30,1976 and accomplished the following tasks: ? Preparation of Data Handling Plan and data acquisition which included visits to twenty mine sites in eleven states, visits to Bureau and MESA facilities, and a literature survey. ? Data analysis which determined the most hazardous type of vehicle for use in the demonstration, and design requirements for the AFCS, ? Development of recommended design concepts for the AFCS. ? Design and development of the AFCS including tests on a full-scale mock-up of a load-haul-dump (LHD) vehicle. ? Underground fire tests on an ST-2B-LHD vehicle at the Hecla Lakeshore mine Casa Grande, Arizona.

Jan 1, 1976

By Koehler Stout

Previous work done by the authors of this report indicates that hydraulically-placed backfill can be strengthened several fold by various placement methods. Sunshine mill tailings were tested by these placement methods and strength increases up to thirty times were achieved over the ordinary placement methods. A computer simulation study of the test stope in the Sunshine Mine showed that a high-modulus fill absorbs up to 27% of normal stresses versus 7% for "normal" fill while reducing maximum convergence 28% versus 8% for "normal" fill. Although high-modulus fill was not placed in the test stope during this contract, various instrumentation was purchased, designed and built to record necessary data in the stope. Stress gauges were placed in the pillars and recorded data corresponded quite closely with theoretical projections.

Jan 1, 1983