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By A. L. Williamson

Bio-mining is a cost-effective, energy efficient and potentially environmentally protective method of exploiting a variety of ore deposits, from high-grade base metal deposits of nickel to lower-grade uranium and rare earth deposits such as are found in the uraniferous quartz-pebble conglomerate beds of the Quirke Syncline, Elliot Lake, Ontario. The effectiveness of bio-mining in Elliot Lake depends on the success of bacterially-influenced dissolution of metals of economic importance. The determination of both the dissolution efficiency and rate controls for uranium and rare earth elements from bio-extraction processes is critical to assess the potential for success of bio-mining along the Quirke Syncline. This poster provides an overview of proton-mediated biogeochemical dissolution of more than 50 elements, including uranium and rare earth elements from samples of the low grade uraniferous ore collected as drill core from the Elliot Lake area. The elemental data is quantified using advanced spectroscopic tools (ICP-MS and ICP-AES) to analyze solutions obtained from a series of environmentally controlled biologically-mediated uranium ore extraction experiments. The findings are being to guide design of larger scale bio-leaching experiments to further assess the potential for success of bio-mining along the Quirke Syncline.

Aug 1, 2010

By Aimee Williamson

Bio-mining is a cost-effective, energy efficient and potentially environmentally protective method of exploiting a variety of ore deposits, from high-grade base metal deposits of nickel to lower-grade uranium deposits such as are found in the uraniferous quartz-pebble conglomerate beds of the Quirke Syncline, Elliot Lake, Ontario, using bacterial metabolic processes are used to enhance the solubilization of the metal(s) of interest. The cost effectiveness of bio-mining in Elliot Lake depends on the bacterially-influenced dissolution metals of economic importance, as well as on the ability to suppress microbiological activity following the release to solution of the economically important elements. This poster provides an overview of elemental recovery results and release kinetics for more than 50 elements. The data is obtained using a combination of advanced spectroscopic tools (ICPAES and ICP-MS) to analyze solutions obtained from a series of environmentally controlled biologically mediated uranium ore extraction experiments. The focus will be on rare earth elements, potential environmentally toxic elements, and metals of economic importance. Furthermore, the importance of these findings will be put into an economic and geologic context for the re-development of the mining industry of the Elliot Lake Camp.

Aug 1, 2010

By Robert Voisey, Robert J. Spencer

"LynnGold's MacLellan Mine is located about 8 km south east of Lynn Lake immediately to the east of the Keewatin River (Fig. I). The property is accessible by an all-weather road, leading north from the provincial highway 391, which links with the Town of Leaf Rapids and the City of Thompson to the south.The ore body, as outlined in the original feasibility study, is expected to produce in excess of 9.3 x IQ6 gm of gold and silver over the next 5 years. However, the deposit is open to depth and exploration is continuing on and around the main zone and the many satellite deposits.The start of construction of the MacLellan Mine and mill was scheduled to phase in with the closure of the Fox copper-zinc mine located 48 km west of Lynn Lake. The majority of the employees from the Fox Operation were either employed at the MacLellan Mine or relocated to Sherrin's Ruttan Operation.GeologyThe MacLellan gold ore deposit is located on the northern section of the Lynn Lake Greenstone Belt known as the Rainbow Trend. This Trend is a 40 km gold bearing rock sequence extending both east and west from the MacLellan Mine. The southern section of these two east-west trending structures is known as the Johnson Shear, this is also gold bearing."

Jan 1, 1990

By P. Condori

Palabora Mining Copper (PMC) has two autogenous mills that have been in operation since 1976. The mills were originally designed to treat 30 000 t/d of open cast copper ore in a closed circuit with cyclones. As the ore body went deeper the open cast method of mining was changed to block caving, a consequence of this was the dolerite content (hardest barren material) increased significantly, increasing the production rate of pebbles and thus reducing the milling capacity. In order to cope with the increased ore hardness and to increase mill capacity, a second ball milling stage and pebble crushing were incorporated to the circuit. The above actions created new challenges to the circuit operation and bottlenecks in different areas of the milling circuit. This paper reports the holistic work performed on the Palabora autogenous milling circuit including the implementation of a mill constraint control scheme, the implementation of a pebble removal system from the circuit and a new circuit configuration. The achieved plant stability and increment of ore throughput are also reported in this paper.

Jan 1, 2012

By J. Makgatho, P. Condori, J. Winnett, Fischerm D.

"Palabora Mining Copper (PMC) has two autogenous mills that have been in operation since 1976. The mills were originally designed to treat 30 000 t/d of open cast copper ore in a closed circuit with cyclones. As the ore body went deeper the open cast method of mining was changed to block caving, a consequence of this was the dolerite content (hardest barren material) increased significantly, increasing the production rate of pebbles and thus reducing the milling capacity. In order to cope with the increased ore hardness and to increase mill capacity, a second ball milling stage and pebble crushing were incorporated to the circuit. The above actions created new challenges to the circuit operation and bottlenecks in different areas of the milling circuit.This paper reports the holistic work performed on the Palabora autogenous milling circuit including the implementation of a mill constraint control scheme, the implementation of a pebble removal system from the circuit and a new circuit configuration."

Jan 1, 2012

By Eddy Dénommé, Deni Villeneuve

"Niobec mine, a producer of pyrochlore concentrates since 1976, became a producer of ferroniobium in 1994 and achieved accreditation to the ISO 9002 standard in 1995. The goal of ISO 9002 is to ensure that the products supplied to clients regularly meet their specifications, through explicit work standards and procedures throughout the production process, from deposit appraisal to ferroniobium production.A key element of ISO 9002 implementation at Niobec consists of the quality control procedures applied to the raw materials: the ore fed to the mill and the pyrochlore concentrate fed to the reduction plant. These controls extend from exploration, deposit appraisal, mine planning and reserves estimation, mining, mineral processing and, finally, ferroniobium production. The implementation of ISO 9002 has allowed more efficient control of the quality of the final product sold to clients. It requires interactive team work, the role of the geologist being to relate all information pertaining to raw material and product quality to the geological framework of the deposits."

Jan 1, 1997

By Xing Jin, Dan Graffi, Glenn MacPherson, Dan Rioux

"The complexity of a modern flotation circuit makes it susceptible to disturbances such as changes in feed, ore mineralogy, equipment degradation, poor measurements and faulty instruments. Good measurements and a robust control system are critical to create and maintain a stable and optimum flotation process.This paper focuses on the development and implementation of process control applications in the flotation circuits at Xstrata Nickel’s Strathcona Mill ( referred to as the mill hereafter ) in Sudbury, Ontario. Following the path of ‘stabilize-improve-optimize’, basic controls to stabilize process variables such as flotation cell pulp level, air and reagent addition rates, cleaning-column feed and wash-water rates have been established. Factors such as best practice in pulp level and valve position measurement, feedforward control and the application of an appropriate control philosophy, have contributed to the significant reduction in process variability. For instance, standard deviation reduction of 79% for the Ni impurity in the column Cu concentrate grade was experienced and is shown. The variability reduction of the flotation circuits’ key process-variables paves the way to further improve and optimize flotation performance. A grams-per-metal unit reagent addition control scheme has been improved upon, particularly for different operating scenarios and better robustness. In addition, following significant stabilization of the primary controls and columns feedrates, Cu/Ni separation cleaning-column bias-control (cascaded to the wash-water rate) and hold-up control (cascaded to air flowrate) have been developed and tested. This strategy – from stabilization to optimization - is expected to achieve a more consistent control of final concentrate grades and improve recoveries.INTRODUCTIONFlotation is considered the most important and value-added process in the milling metallurgical plant and is still undergoing continuous evolution to treat greater tonnage and different ores (Wills, 2006). Starting over three decades ago, with the advent of on-line slurry content analysis devices, flotation automatic control has received persistent interest and a large number of applications have been reported (Thwaites, 1983, 1986 ; Mckee, 1991). Bergh and Yianatos (2011) reviewed different aspects of process control in flotation circuits and have evaluated the applicability of model predictive control to the process. Mckee (1991) analyzed the difficulty in developing lasting/robust process control applications for flotation circuits and stated that the path of stabilization-refinement-optimization would more likely lead to successful flotation circuit process control. Best practice on column process control was discussed by Bouchard, etc. where a multi-layered approach was proposed, provided that the measurement of column process variables ( i.e. bias, froth depth, hold-up, etc. ) are measured reliably (Bouchard & Thwaites, 2008). Wills (2006) stated that the best practice for flotation automatic control starts with fulfilling basic control objectives, such as stabilized flotation cell level, air flow, pH, reagent flow etc., before considering more advanced, or even optimal, control of metallurgical targets, which are more closely linked to economic performance."

Jan 1, 2013

By Robert Gannicott

??A mining company without the burden of operating a mine ??Management focused on marketing a high-quality, run-of-mine range of Canadian diamonds ??Robust revenue stream ??Specialist diamond knowledge ??Canadian exploration and development expertise ??BUT ??Single asset revenue base from depleting ore reserve ??Limited influence on production plans

Apr 1, 2005

By Bill Dupley

We believe that the inability of employees to effectively manage information has reached an epidemic problem throughout the corporate world. ? All the available knowledge in the world is accelerating at a phenomenal rate. ? The whole world's codified knowledge base (all historical information in library books and electronic files) doubled every 30 years in the early 20th century. ? By the 1970s, the world's knowledge base doubled every seven years. ? Information researchers predict that by the year 2010, all the world's codified knowledge will double every 11 hours.

May 1, 2003

By E. Onal, C. Craddock, A. Chapman, M. R. Endsley

ABSTRACT Mining equipment operators must interpret and respond to complex information delivered by technology-centric rather than user-centric systems. The ability to achieve high situation awareness (SA) in the face of this data overload is a key challenge to effective decision-making and information exploitation. Incidents attributed to human error that compromise safety and result in loss of revenue, or even life, are often the result of system designs that overload human cognitive capabilities. This paper defines SA as it relates to the operation of mining equipment and describes the design and preliminary evaluation of a new electric shovel operator user interfa

Jan 1, 2013

By E. Onal

Mining operators are faced with complex information delivered by technology-centric rather than user-centric systems. The ability to achieve high situation awareness (SA) in the face of this data overload is a key challenge for effective decision making and information exploitation. Incidents that result in loss of revenue and even life, and compromise safety that are attributed to human error are often the result of system designs that overload human cognitive capabilities. This paper focuses on defining SA as it relates to mining operations and presents methods for improving SA through a scientific approach for electric shovel operator user interface development.

Aug 1, 2013

By Tom Olsen, Tom Ohrling, Peter Taggart, Chris Martin

"North American Palladium commissioned the new concentrator at the Lac des Iles mine in the summer of 2001. The 15,000 tonnes per day mill replaced the existing 2,400 tonnes per day facility, as part of a major mine expansion.At Lac des Iles, the grain size distribution of the platinum group minerals (PGM) is bi-modal. Roughly two-thirds of the PGM are relatively coarse-grained, and often associated with fast floating copper and nickel sulphides. The remainder is ultra-fine, and locked in silicates, which poses a special challenge to the metallurgist. The previous mill typically recovered just the fast-floating mineralisation, but to achieve target recoveries, the new mill has to recover a substantial amount of the ultra-fine PGM. The metallurgical challenges associated with the recovery of fine-grained PGM in the talcous Lac des Iles ores, are described.The paper describes the approach used in circuit optimisation, and how metallurgical and operational optimisation raised palladium recoveries by more than 6% in six months, by tuning the circuit to recover some of the ultra-fine PGM mineralisation.BACKGROUNDThe Lac des Iles mine, owned and operated by North American Palladium Limited, is located about 115 kilometres north of Thunder Bay, Ontario. The mine originally opened in December 1993, and prior to 2001 included a mill capable of handling 2,400 tonnes per day of ore delivered from the nearby Roby pit.Following an intensive exploration programme conducted in 1999, and a detailed feasibility study, conducted in 2000, North American Palladium initiated a mine expansion project, the objective being to expand milling throughput from 2,400 tonnes per day to 15,000 tonnes per day. This required construction of an entirely new mill, which was commissioned in May 2001."

Jan 1, 2003

By J. A. Ressinger

"The purpose of this paper is to discuss some of the differences between various methods of excavating and loading as they relate to mining operations. The intent is not to provide ""pat"" answers, but instead to raise some questions and set forth some reasonable guidelines.Specifically, the paper deals with the differences and relative merits of power shovels versus rubber-tired front-end loaders - or, carrying this further, comparing what could be called ""stationary"" loading or excavating devices to ""mobile"" types."

Jan 1, 1972

By 000-900-009-492

The flotation has been and is still the most widely used mineral concentration method. Because of its complexity, the flotation process required the development of robust control strategies which was facilitated by the introduction of on-line sensing instruments such as x-ray fluorescence (XRF) on stream analyzer (OSA), gamma density gauges and electromagnetic flowmeters. The interest in developing control strategies has persisted because the benefits to be gained in terms of improved metallurgical performance are substantial. As the flotation control becomes more and more difficult due to the emergence of low grade and complex ore cases, other control strategies have to be introduced. Froth based control is one of the emerging useful control strategy This paper will focus on the state of the art in the on-line froth characterization as obtained by numerical image analysis. The technology of machine vision provides a novel solution to several of the problems encountered in conventional flotation systems for monitoring and control, and constitutes a powerful tool for the investigation and interpretation of the effect of various flotation parameters as driven for the froth phases. Copyright @2001CIM

May 1, 2001

By Patrick Pelletier Jr., Pierre-Alexandre Bossé, Gianni Bartolacci, Ian Orford, Steve Parent

"Over the last decades, many authors have shown the importance of froth in the flotation process. Mineral recovery is related to froth recovery and flotation. Selectivity is affected by froth characteristics, especially structure and loading. The characteristics of froth textures could therefore be used for diagnosing flotation.Machine imaging, especially image texture analysis, allows on-line measurement of important froth characteristics and process state classification. The measured characteristics include froth texture, loading and stability indicators. To extract information from images, texture analysis tools are used as well as a block-matching algorithm (BMA). For process state classification, images are analyzed with the same tools and clustering is done with multivariate data analysis algorithms.Two case studies, Brunswick Mine Concentrator Cu/Pb circuit and LaRonde Mine Zn circuit, are presented to show that these indicators may be used for diagnosis and control. The influence of manipulated variables on measured froth features is shown as well as the relationship between froth characteristics, mineral recovery and flotation selectivity.INTRODUCTIONImaging is a way to depict abstract characteristics of a scene or an object; it is often related to other types of scientific observations, chemical component concentrations, for example (Geladi and Grahn, 1996). In this paper, the scene is flotation froth. Imaging can be especially useful in applications where it is difficult to obtain the measurements needed for process analysis – froth flotation, for example."

Jan 1, 2006

By Oliver C. Ralston

DURING the development of froth flotation for the treatment of sulphide ores, a certain amount of information was collected about a few of the nonmetallic minerals, and occasionally the gangue minerals in the sulphide ores showed an embarrassing tendency to float. However, for many years efforts were expended to develop reagents that would cause wetting and depression of these minerals. Among the nonmetallics, the minerals sulphur, graphite, and talc probably should be classified as 'natural floaters', and perhaps sericite. They respond to almost any type of flotation reagent, and their beneficiation by flotation had been attempted years ago. Flotation of sulphur is now common practice, and graphite was concentrated during the World War in many mills, most of which have now closed down. A talc mill has just been constructed, and another may soon be erected. Second to the 'natural floaters' come the 'easy floaters', cassiterite, fluorite, barite, mica, colloidal gangue, and paper pulp from white water of paper mills. That these materials responded to some of the early flotation reagents, as oleic acid, has long been known; occasional references to their behaviour are found in the very early flotation literature and in that of today. In general, however, nonmetallic minerals, valued at $2.00 to $15.00 per ton, have for a long time been regarded as cheap products and not worth much beneficiation. Consequently, only high-grade natural deposits suitable for direct mining and sale have been gouged out. Furthermore, the mining of these minerals has too frequently been in the hands of 'super-practical' men-men of no technical or other training, willing to work for a very low compensation. From the social standpoint, nonmetallics has been the field for small, untrained enterprisers with little money to spend on plant or equipment. But times have been changing. The impact of technically trained men on the old industry has revealed appalling losses and inefficien-cies and proved the value of processing materials discarded or avoided by the old regime.

Jan 1, 1937

By J. X. Guo, A. Pindred, J. Moore

"Two modified centrifugal flotation cells (CFC), Q2 and Q3 models, have been developed for froth flotation. The operating mechanism of Q2 uses a rotating bowl to create a centrifugal force on the feeding slurry. Froth concentrate is collected on the central top of the cell and tailing is discharged along the top edge of the rotating bowl. The Q3 utilizes a vertical rotating feed pipe to introduce the feed slurry into a stationary flotation column cell. A centrifugal force is also created by a rotating pipe for the feeding slurry. Froth concentrate floats over the cell and tailing discharges through the bottom of the cell. The centrifugal force causes the flotation recovery of fine particles from CFC to be higher than from the conventional cell. The major operating variables of CFC are the rotating speed, air flow rate into feed slurry, and slurry feeding rate etc. Flotation tests have been carried out on synthetic mixtures of galena-silica and chalcopyrite-silica, as well as some natural base metal ore samples. Parallel tests were also conducted on a conventional flotation cell. The comparative test results demonstrated that both Q2 and Q3 have the advantage of higher recovery of finer than 10 µm mineral particles, which are very difficult for the conventional non-centrifugal flotation cell to recover. The grade-recovery curves produced from CFC are equivalent to or better than the conventional flotation cell. There is a potential in the future for the CFC to be employed in slime flotation.1. IntroductionA centrifugal flotation cell (CFC) was originally developed by Clean Earth Technologies [I] to separate oil from water and was subsequently applied in froth flotation. Figure 1 illustrates the design of the original CFC, in which a vertical feeding pipe is attached to the center part of a rotating drum and a stationary shell encloses it to direct the float froth and tailing discharge. The slurry flows down to the bottom of the spinning drum, gets in touch with a screen of air bubbles and then migrates outwards under the effect of centrifugal force. After the mineralized froth enters the rotating cell, it is pushed back to the inner surface. The overflowing froth is collected in the froth launder while the tailing slurry is discharged through orifices along the outer rim of the drum."

Jan 1, 1998

By R. R. Klimpel

"SYNOPSISA discussion of the importance of flotation rate in the analysis of mineral flotation is presented. In particular, the highly interactive nature of the flotation ""system"" is emphasized where there are components of chemistry, equipment, and operating conditions simultaneously involved. It is further shown that: 1) flotation rate must be measured in order to economically optimize the performance of an industrial flotation circuit, 2) that consistent patterns exist in both flotation rate and equilibrium recovery when changing various settings of the system components, 3) that knowledge of these patterns is necessary in order to avoid making system changes that are either self-compensating or dramatically re-enforcing in some particular aspect of performance, and 4) the rate related role of the chemistry component (e.g.frothers and collectors) is often much bigger than is sometimes realized (especially in a negative sense involving overdosing of reagents). INTRODUCTIONFroth flotation is widely usedl-6 in mineral beneficiation processes as a method for separating different types of finely divided solids present in a liquid (usually aqueous) suspension. The approach is based on the contacting of solids with upward moving air bubbles in an agitated vessel where the solids are exposed to chemicals (collectors) which create a condition favoring the attachment of a certain portion of the solids to the air bubbles. This selected portion is then removed in a froth stabilized by chemicals (frothers) and subsequently recovered from the flotation vessel. Depending on the settings of the various components of the flotation ""system"" (see Figure 1) it is possible to achieve a wide range of flotation performance."

Jan 1, 1984

By J. -C. Sztuke, M. Cao

ABSTRACT The correlations between froth recovery of coal and air recovery were investigated using a hybrid mechanical flotation column. The particle slurry was fed onto the surface of air-water two phase froths to carry out the tests. Froth recovery was taken as the recovery of particles into the froth product, whereas air recovery was determined by the froth height method. The relationships between froth recovery and air recovery were nearly linear, with greater slopes for more hydrophobic particles. Inside the froth phase, the particles were stratified, with hydrophobic particles concentrated in the upper region and hydrophilic particles in the lower region.

Jan 1, 2013

By M. C. Harris

The past twenty to thirty years have seen unprecedented research activity aimed at understanding the performance of flotation froths. In 1990, Finch and Dobby coined the term froth recovery factor, Rr, to represent the efficiency of the froth in delivering particles from the pulp-froth interface to the concentrate. Originally defined for flotation columns, Rr has also been found useful in modeling mechanical flotation cells, and a number of techniques, based on quite different approaches, have been developed for measuring the froth recovery in industrial flotation cells. None of these techniques is universally successful. This paper reviews the concept of the froth recovery factor, and the basis of each of the techniques that have been proposed to measure Rr, and examines the reasons for this parameter being so difficult to pin down. Advances in Mineral Processing Science and Technology Proceedings of the 48th Annual Conference of Metallurgists of CIM Sudbury, Ontario, Canada Edited by

Jan 1, 2009