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By D. Schleiss

Reduced access to knowledgeable workers is creating challenges for operations. We are doing more 4D Operations - dirty, dull, dangerous, and distant. Personnel costs in these environments are high, and it is not always possible to get the people where you need them. Integrated Operations is a strategy to integrate people, process, and technology for faster and better decision making. Adopting an integrated operations approach can help to relocate personnel, improve collaboration, and align objectives to deliver reduced costs and improved performance. In this paper, the authors will highlight the required infrastructure to enable an Integrated Operations platform. Key decision points for enabling this technology for both Greenfield projects and existing mines will be discussed. Furthermore, the benefits and improved return on investment that result from deployment of an Integrated Operations strategy will be presented.

Jan 1, 2014

By S. Kursunoglu

The aim of this study was to investigate the effectiveness of Ascorbic (C6H8O6) Acid (AA), Activated Carbon (AC) and Guar Meal (C6H12O6) (GM) as a reductant for the simultaneous complete dissolution of zinc (Zn) and manganese (Mn) from a spent and mixed Zinc-Carbon (Zn-C) and alkaline battery powders in sulphuric acid (H2SO4) leaching. AA was tested previously as a reductant by other researchers while AC and GM were tested as a reductant for the first time in battery recycling. The effects of H2SO4 concentration, AA/AC/GM dosages, reaction temperature and leaching time on the Zn and Mn dissolutions were investigated according to 2k full factorial experimental design and Central Composite Design (CCD) technique; then, a simple optimization study was carried out for comparing the reductants. The optimum reductive acid leaching conditions for AA were determined at 3 hours leaching time, 70°C leaching temperature, 0.5M H2SO4 concentration, 13 g/L AA dosage, 1/20 g/mL solid/liquid (S/L) ratio and 200 rpm stirring speed. Under these conditions, the dissolution efficiencies were 99.9% for Zn and 99.3% for Mn. The best reductive acid leaching conditions for AC were determined at 3h leaching time, 80oC leaching temperature, 1M H2SO4 concentration, 3 g/L AC dosage and 400 rpm mixing speed. Under above conditions, Zn and Mn dissolutions were not complete. At 2M H2SO4 concentration, 10 g GM dosage, 700C leaching temperature, 200 rpm stirring speed, 1/20 g/mL solid/liquid (S/L) ratio and 3 hours leaching time, full dissolution of both Zn and Mn was achieved. As a result, three different reductants were evaluated in this study for complete simultaneous Zn and Mn dissolutions. This paper also compared present test results with previous spent battery recycling studies for Zn and Mn dissolutions. Full valuable metals dissolutions from spent batteries were achieved at low H2SO4 concentrations with AA and high concentrations with GM. Selective precipitations of Zn and Mn from acid solutions were carried out using NaOH and KOH. Using 3M NaOH as precipitating agent at room temperature and at pH 8; 95.4% of Zn and at pH 10; 93.7% of Mn were precipitated from the leach solution. Under the same conditions, using 3 M KOH at pH 8; 91.6% of Zn and at pH 10, 96.4% of Mn were precipitated. Based on the experimental results obtained, an appropriate flow sheet was proposed to recover both Zn and Mn.

Aug 1, 2013

By L. C. Lien

Tower crane layout (TCL) is a typical construction site layout (CSL) problem, which is suitable for a wide range of work assignments and site conditions. Tower crane is one of the key facilities for vertical and horizontal transportation of materials, especially for heavy prefabrication units such as steel beams, ready mixed concrete, prefabricated elements and large panel formwork such as machinery and equipment, and a wide variety of other building materials within a construction site. However, it is a difficult combinatorial optimization problem to determine the locations of tower cranes with materials quantity supply and demand for engineers. Swarm intelligence (SI) was very popular and widely used in many complex optimization problems which was collective behaviour of social systems such as honey bees (bee algorithm, BA) and birds (particle swarm optimization, PSO). This study applied a hybrid swarm algorithm namely particle bee algorithm (PBA) based on a particular intelligent behaviour of honey bee and bird swarms by integrates theirs advantages. This study compares the performance of PBA with BA and PSO for a proposed hypothetical construction engineering of TCL with materials quantity supply and demand problem. Results show that PBA performs better performance than the mentioned algorithms on a proposed hypothetical TCL problem.

Aug 1, 2013

By K. Horikawa, S. Kitahata, H. Kobayashi

"It has been clarified that the Al-5%Mg alloys containing 200 mass ppm of sodium showed grain boundary (GB) fracture, even when tested at room temperature, as well as at high temperatures (~500°C). SEM/EDX study revealed that the GB fracture was associated with the segregation of sodium on grain boundaries of the Al-Mg base alloys. Differential scanning calorimetry (DSC) revealed that the GB fracture at room temperature of Al-Mg alloys was caused by sodium segregation in the solid state. It was also shown that the tendency of the GB fracture strongly depended on the heat treatment; the alloys after the solution heat treatment showed severe GB fracture compared with the alloys after the homogenizing treatment. Moreover, it was shown that the GB fracture at room temperature by sodium segregation was suppressed by the addition of bismuth or indium. The suppression of the GB fracture by the additional elements was believed to be the scavenging effects by forming the sodium bearing compounds in grains.INTRODUCTIONIt is widely known that Al-Mg base alloys containing high amount of magnesium(~5 mass%)show better workability at room temperature, while that the alloys show grain boundary (GB) embrittlement at higher temperatures ranging from 200 to 500°C, depending on grain size(Otsuka, 1984), sodium impurity level(Ransley, 1959, Okada, 1997, Horikawa, 2001)and testing strain rate(Yamada, 2012). In the case of coarse-grained Al-5%Mg alloys (~300 ?m), 2 mass ppm of sodium causes severe GB fracture around 300°C, however, the Al-5%Mg-2ppm alloy does not show GB fracture at room temperature. It has also been shown that the GB embrittlement caused by 2ppm of sodium was suppressed by the additional elements, such as bismuth (Talbot, 1995), antimony (Ueda, 1997) and indium (Horikawa, 2012). Basedon these facts, we have concluded that the GB embrittlement at higher temperatures of Al-Mg alloys is attributed to the synergy effects of GB segregation of atomic sodium and GB sliding. For the GB embrittlement mechanism of Al-Mg alloys, involvement of low melting point metallic phases has been pointed out (Lynch, 2002),since the GB embrittlement appeared only at high temperatures. Up to date, the effects of high amount of sodium addition more than 2 ppm on GB fracture were not fully investigated in Al-Mg alloys. In the present study, the effect of 100 ppm ordered sodium impurity on GB fracture of Al-5%Mg alloys was examined, together with the effect of another additional elements."

Jan 1, 2017

By McNeely DuBose

INTRODUCTORY PROSPECTING for aluminum has always been, and still is, a peculiar combination of the technical with the physical approach, and 1 want to explain my conception of the term 'prospecting' when applied to aluminum, which differs in some respects from the ordinarily accepted idea of prospecting. In the early days of gold mining, prospecting was a search in the hills and the river beds for the metal, not for its chemical combinations. And so it was in the early days of aluminum, with the difference that the search for the metal was carried on, not in the hills and dales, but in chemical laboratories. Aluminum is never found in the elemental state and at that time the metal bad never been seen, but scientists of that day bad forecast that such a metal must exist and in 1807 Sir Humphrey Davy went so far as to give this unseen metal a name, aluminum, from the Greek word alumen. This word applies to our alum, and it was from alum that Davy sought to produce the metal. It is strange to think that, in laboratories throughout England and on the continent, prospecting for aluminum was busily under way by men who had never seen the metal they were searching for. Their situation was something like that of the fisherman and the 'big one' that got away. They could describe the metal, give its exact weight, and even name it, but they could not produce visual evidence of its existence. Eventually, however, the efforts of the scientist 'prospectors' were rewarded and in 1826 the metal was actually produced, possibly first by Wohler, though Oerstedt, a Danish chemist, is usually credited with the achievement.

Jan 1, 1951

By R. D. Brown

In his April 10, 1978 budget address, Finance Minister Chretien declared that the federal government will restrict the growth of its spending to less than the trend growth of the gross national product; over the past year, both the federal and a number of provincial governments have taken action to cut back on spending policies. This new emphasis in restraint would seem 10 be a response to a mounting public reaction to the rapid growth of government spending - and taxation - over the past 25 years. Although this relatively new government posture on public spending may be admired by many, to others it raises the question: "Can the growth in government spending really be stopped?" This article comments on just how government revenues - and spending - have grown over the past few years in Canada, and mentions some of the issues relating to a slowdown in that growth.

Jan 1, 1978

By P. Morissette

Passive monitoring of support performance during rockbursts was conducted at three deep underground mines. A comprehensive database was constructed of 172 seismic events and the associated damage to support systems at 266 mine locations from January 2000 to September 2012. The majority of pertinent information was obtained through seismic system records and on-site field assessments. This work assesses the quality of collected information and evaluates the dynamic-load demand on support systems in seismically active mines.

Aug 1, 2013

Background Chronology 2008 Positions May 8, 2010 Summit Going Forward Say one thing and do another ??Genuine passion to see our customers succeed?, ?A passion for exceeding our customer?s expectations? Self serving actions to gain competitive advantage at the expense of the customer No single supplier or technology can manage the overall mine and its integrated operation - April 2005: Informal meeting at Toronto CIM 2004 -Unanimous interest - July 2005: Formal Calgary Meeting, developed: - Scope and vision statement , - OEM/OTM communication plan, - industry communication plan - Aug?Nov 2005: Aligned with SMART - Nov 2005?May 2006: Direct OEM, OTM communication - May ?Sept 2006: Developed baseline standards - Sept -April 2007: Developed SMART document - Sept 2007: Document distribution and request OEM OTM response - Jan ?May 2008: Acquired OEM OTM feedback and positions May 2008: Results presented to SMART and discussions on next steps

May 1, 2010

The Stability Graph Method is widely used in Canadian underground hard rock mines for open stope support design and is frequently used in the mine planning phase to assess the viability of stope geometries and to determine maximum permissible spans. The Method is well accepted due to its simplicity and suitability to a wide range of mining methods requiring the use of sublevels to access and extract the mining blocks. While this Method is reliable in situations where the maximum induced tangential stress creates adequate compressive stress keeping the face in a state of confinement, the Method fails to reflect the effect of low confinement caused by lower compressive stresses and instances where tensile stresses are developed. In this paper, a new Rock Stress Factor, A?, an update to the original Rock Stress Factor, A, is proposed, which will reflect the impact of low confinement or overstress regime on critical face stability. Two case studies, based on two Canadian operating gold mine shows that using the new Rock Stress Factor A? to predict the stability of stope hanging-wall and footwall gives better agreement with the CMS survey results, compared with the prediction using the original rock stress factor.

May 1, 2011

By P. Nayak

"Comminution is an energy intensive and expensive process consuming approximately 40-50% of the total processing costs in a mining operation. This process poses an even greater challenge with gold ores due to their low elemental concentration and small particle size. Over 99.9% of the ore fed to the mill is waste which must be removed during the ore processing stage. Preconcentrating the Run of Mine (ROM) ore before feeding the mill will result in significant cost savings. In partnership with Sacré-Davey Engineering, Agnico Eagle Mines Limited identified this opportunity and is currently evaluating the implementation of sorting technology to preconcentrate the ore or upgrade the waste material at its operations. This paper will discuss the steps adopted by Agnico Eagle in the evaluation and installation of sorting technology at its operations. Since the Company has a large portfolio of operations, the first step in the project was to shortlist the operations that had the highest probability for successful application of the technology. Following this, the top three operations were selected for bench scale evaluation. The projects which showed the most economic potential were then considered for detailed evaluation and pilot plant installations. This paper provides an insight into the methodology followed by Agnico Eagle and Sacré-Davey in the evaluation of the technology.INTRODUCTION The benefits of ore sorting technology are being increasingly understood by the mining industry today. The application of ore sorting in gold mining is attractive due to the nature of the mineral distribution. The presence of high value minerals distributed in an extremely small mass of the ROM ore creates a tremendous opportunity for preconcentration with ore sorting. Since Agnico Eagle currently has a portfolio of eight operating mines and numerous development projects and exploration properties, the challenge was to identify the deposits which had the most favourable mineralogy and grade distribution for successful ore sorting. The success of ore sorting is mostly based on the minerals present in the deposit and the grade distribution. The minerals signify the amenability of the deposit for ore sorting and the kind of sensing technology to be used. On the other hand, the grade distribution demonstrates the amount of material that can be rejected without losing value. In order to understand a deposit’s characteristics, it is important to examine the sample’s behaviour with various sensors and then assay it to know its actual value. It is a common practice in the mining industry to document assay value of drill cores and/or material feeding in and out of the mill. However, those VALUES (are insufficient to understand the grade variability on a granular basis. To capture the ore variability in very high resolution and significantly improve the selectivity of the material feeding the mill, it is vital to assay the samples on a rock-by-rock basis, as this is the level of resolution which will be examined by the ore sorter during sorting. A careful and elaborate procedure was followed in evaluating the technology at Agnico Eagle’s operations which is discussed in this paper."

Jan 1, 2019

By Liangtian Liu, Tie Ou, Guangqiang Li, Chenghuan Yu

For stabilizing the production of containing nitrogen steels, a study on nitrogen absorption behavior of killed molten steel has been carried out by means of the RH vacuum device in which nitrogen was used as a driving gas. The results showed that there was an increase of nitrogen content in molten steel under vacuum processing but the rate of nitrogen absorption was slowed down by the surface active elements. Therefore, a kinetic equation for nitrogen absorption of molten steel with apparent first order reaction was derived by constructing a modified model in which the adsorption of closed surface site was taken into account. The experimental results confiimed that the calculated values agreed with the observed ones. This model is suitable for the prediction of nitrogen adsorption operation for containing nitrogen steels.

Jan 1, 2004

By D. Furrer, M. Dallaire

The arrival of Image analysis in the last 20 years has changed the world of quantitative metallography. Many standard measurement techniques which were previously manual can now be done with fully automated systems. This reduces subjectivity and operator fatigue and therefore enhances the quality of the statistical results. In many laboratories, Titanium Alloy microstructures continue to be evaluated by traditional methods, where quality of results is subject to operator fatigue and level of experience. Advances in Camera technology have tremendously improved image acquisition. One can often see clearly at 500x what can not be observed at 1000x, allowing for a larger area to be analyzed, without the inconveniences associated with very high magnification objectives. Powerful and versatile Image analysis software combined with a high precision motorized stage gives access to a multitude of applications, which were extremely challenging or impossible until now. Image Analysis tools such as Multilayer Grab, which reconstructs an uneven image into one plane of focus (ex. Observation at high magnification of texture resulting from etching) and Mosaic which builds an image from a number of fields of view (ex. Reconstruction of very large grains at low magnifications) expand even further the power and flexibility of IA systems. This presentation will describe how automated methods are applied to the point count method and grain size measurement. We will show how cameras and software work together to permit quantitative measurements of primary alpha and prior beta microstructures, as well as lamellar alpha plate thickness in titanium alloys.Automated and semi automated quantitative measurements of various Titanium microstrures have been assessed, using the Clemex Vision PE. Examples of the methods and steps used are presented.

Jan 1, 2006

By C. H. Knight

"THE OBSERVATIONS that follow are confined to simple wet cyclones such as the cylindro-conical unit developed by the Dutch States Mines and marketed in America under the trademark 'Dorr-Clone'. Energy to do the work comes from the inlet velocity of the feed slurry, which is usually pumped' to the unit by a centrifugal pump.Such cyclones are simply classifiers of enormous capacity and depend for their separating effect on differences in rates of particle settlement. These particle settling rates, of course, vary with particle size, particle density, particle shape, pulp viscosity, and pulp density.The dilution of the overflow product affects both pulp viscosity and pulp density. In most operations, the temperature and the composition of the liquid -hence its viscosity --are fixed, but both pulp viscosity and pulp density can be changed by changing pulp dilution.Since the separating effect depends on differences in rates of particle setting, a perfect split with 100 per cent of the particles coarser than a given size in the underflow and 100 per cent of the finer sizes in the overflow is not possible. Just how far the separation departs from this perfection can be calculated rather exactly from the following principles, which also apply to mechanical classifiers. In removing or settling out of the overflow product all particles up to a specified size, some of the finer particles must settle out simultaneously."

Jan 1, 1955

By Floyd Smith

Based on underground observations made in .the coal mines of the Dominion Coal Company Ltd., this paper deals with the stress phenomena in the approach roads and headways and in the gob areas associated with the longwall method of total extraction. The deformation of roadways during development and the deformation of roadways during the total extraction period is delineated and presented in graphical form .. Conclusions are made as to the feasibility of the introduction of the retreat method of longwall extraction in one of the colhenes. The importance of future studies are enumerated, especially. those pertaining to the determination .of the opti.m.um sizes of protective pillars and to increasing the efficiency of the current methods of artificial roadway support.

Jan 1, 1967

By F. A. Forward

"NINETEEN sixty-six is a year of unusual significance in our Institute and in our country. It marks two-thirds of a century of service by the Institute to the people of the mineral industry and two-thirds of the century that Sir Wilfred Laurier said ""belongs to Canada."" As we meet here today within the historic walls of Canada's oldest city, a city that looks back on three hundred and fifty years of progress, I am reminded that it is almost a third of a century ago -in April, 1934 -that here in Quebec I first attended an Annual General Meeting of the Institute. It occurred to me that it might be appropriate to examine briefly the change that the middle third of this century has brought in the affairs of the mineral industry and, with some trepidation, to consider the prospect for the third that lies ahead.Opinions differ as to the relative importance of factors that have been responsible for the expansion and growth of Canada in its first hundred years. Some will say that it has been due to the abundance and fertility of agricultural land, others to the early enterprise of the railroads, and financiers believe that the banking system has been a major factor; -the fisherman -the forester -the teacher -each has his own view. I suspect, however, that most of us here would subscribe to the thesis of T. A. Rickard -miner, author, imperialist -who wrote, a gene-ration ago, ""Trade follows the flag, but the flag follows the pick,"" and thus agree that the finest contribution to progress, to wealth, to extension of frontiers and to inter-national trade has been provided by the mineral industry."

Jan 1, 1966

By L. M. Amaratunga, G. G. Hein, D. N. Yaschyshyn

Fine tailings produced in the milling process have traditionally been disposed of in tailings ponds. Attempts have been made to use these fine tailings in backfill, however, to date the majority of backfill operations have utilized only a small percentage of fines. The remaining fines are, therefore, being sent to tailings ponds creating a waste disposal and environmental problem. This disposal practice is even more acute in the gold milling industry where fine grinding, required for value liberation, results in the production of large quantities of fine tailings, of which a large percentage cannot be used in backfill. Through Cold-Bond Tailings Agglomeration (CBTA), these fine tailings can be agglomerated into pellets which can then be used as a coarse aggregate in back-fill. This paper presents the results of using these pellets to create an Agglomerated Tailings Paste Fill (ATPF) made entirely of fine gold mill tailings and cementing binders. Through this process, supplementary imported aggregates such as sand, gravel, rock-chips are not required while still maintaining adequate back fill strength. By using this CBTA technology, fine tailings are diverted from tailings ponds and becomes utilized as a value added resource in the form of aggregates for use in paste fill.

Jan 1, 1997

By Adrian Rosen

When one thinks of innovation and leadership in wireless communications, one would rarely consider a potash mine to be leading the way. Agrium Incorporated has proven that they are leaders and innovators, as is evident in their recent deployment of a large-scale 802.11 wireless network in their underground potash mine located at Vanscoy, Saskatchewan. 802.11 is an IEEE standard for Wireless Local Area Network (WLAN) technology. Rather than simply replace an aging communications infrastructure, Agrium chose to let technology provide the framework for future success

May 1, 2006

By G. Guzman

In the framework of the optimization of Teniente Converter operation the new system of automatic flux feeding through gar-gun was implemented in the Potrerillos Smelter, Codelco Chile, Salvador Division. The control algoritm based on simple iron and silica balance adjusted by empirical coefficients was incorporated in the logical programmer. The programmer works in real time gathering information from the plant instrumentation events and introduced chemical assays of concentrate, slag and flux. Through the auto-tuning of the automatic operation the criterions of optimal flux dosage were determined. Four month of operation of the automatic flux feeding system demonstrated the stabilization of magnetite content in the slag in the narrow range from 18 to 20% and the decrease of flux consumption, corresponding to annual savings US$ 340,000. Additionally, the automatic system helps operators in the control room in fast determination of optimal fluxing and avoid the errors in flux dosage affecting the slag quality and its impact on refractory wear.

Jan 1, 2007

The Autogenous milling of ores holds an increasing attraction as the focus moves towards reducing energy usage, both direct and embodied in grinding media. However, most of the early AG mills were converted to SAG for improved stability and increased throughput. This imposes a huge penalty in steel grinding media consumption. The LKAB iron ore operations in Sweden process highgrade magnetite through fully-autogenous milling lines to a final product P80 of about 45µm. The outcomes of P9O AMIRA research surveys, covering a wide range of mill fillings and throughputs and with different feed blends, are presented. Insights are provided on operational strategies, opportunities, the influence of feed size control and balancing the blend of competent gangue and softer magnetite. Areas of importance in the successful operation and control of energy-efficient autogenous circuits are highlighted.

Jan 1, 2012

By M. G. Stamatakis, C. Zagouroglou, C. Helvaci, J. Kanaris

"Abstract -Borate minerals, such as colemanite, ulexite and borax, have been reported in Tertiary continental basins of West Anatolia, Turkey, and Samos Island, Greece.Tuffaceous rocks interbedded with the borates are rich in authigenic silicate minerals such as zeolites, potassium feldspar and opal-CT, all of which have a genetic association with the borates. Chemical analyses of the tuffaceous rocks show variation in major elements due to the varying percentage of carbonaceous, detrital, and volcanic derived material.The volcanic activity in the vicinity of each particular lacustrine basin created ion-rich fluids from which a series of borates were precipitated under arid climate. Additionally, the saline-alkaline character of these fluids was responsible for the diagenesis of the silicic glass of the tuffaceous rocks, altering them to silicates and silica polymorphs."

Jan 1, 1993