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By A. F. Banks

"The last time I spoke to you the potash industry was at a low point. Markets were bad and the industry depressed. Many people had left and there was very little being done in terms of development. The current situation is very much changed. The oversupply conditions have given way to a very tight supply capability. All of the firms in the business are expanding in one way or another. These expansions will run from simple debottlenecking through to complete new projects.In New Brunswick, the Potash Corporation of America is proceeding with a new project and the Dennison - Potacan Project is in progress. In Saskatchewan, the Potash Corporation of Saskatchewan has an ambitious 2.5 billion dollar expansion program underway while those in the private sector are taking a somewhat less ambitious but equally significant approach to obtain further tonnage out of existing facilities.The significance of these expansions to mineral processors is that we can expect to see expanded employment opportunities and through necessity a surge in innovation and development in an industry that has been traditionally very conservative. This presentation will review potash processing with a view towards highlighting some of the more recent developments."

Jan 1, 1982

By Adam Wright

"Les Mines Selbaie have been producing copper and zinc concentrates from the A-1 ore zone since 1986. This paper reviews major developments in flotation practice over that period. Firstly, ore blending strategies for Selbaie's non-homogeneous polymetallic ore are discussed. The evolution of reagent use is then reviewed, focussing on copper collector trials. A description of Selbaie's flotation columns follows. Finally, past and future developments for process control are outlined.Depuis 1986, Les Mines Selbaie produisent du concentré de cuivre et de zinc provenant de la zone A-1. Cette conférence présente !es développements majeurs en flottation qui ont eu lieu depuis ce temps. Premièrement, la stratégie du mélange de minerai non homogène polymétallique est présentée. L'évolution des réactifs utilises est démontrée, particulièrement !es collecteurs de cuivre. Par la suite !es colonnes de flottation sont presénteés et finalement !es développements futurs ainsi que ceux qui ont eu lieu dans le contrille de procédé sont expliqués.1.0 INTRODUCTIONLes Mines Selbaie, wholly owned by Billiton Metals Canada Inc., is currently mining and processing ore from a polymetallic surface deposit located 288 km northwest of Val D'or, Quebec (fig. 1). The mine produces copper concentrates containing gold and silver as well as zinc concentrates containing silver. 8000 dmt/day of ore is crushed and ground to 80% passing 49 µm, prior to processing by conventional copper/zinc differential flotation. The flotation circuits consist of both conventional and column cells (fig. 2). Detailed descriptions of the mill are available elsewhere in the literature (8,9)."

Jan 1, 1995

By A. Vien, B. C. Flintoff, R. P. Edwards

"This paper provides a critical review of the development and application of advanced controls in mineral processing at the industrial level. These algorithms can be sub-divided into four broad categories: Kalman filter, self-tuning, extended horizon, and knowledge based or expert systems. Applications from each category are described outlining the benefits derived, the relative advantages of that particular controller, and potential limitations of the controller which may inhibit their more widespread application. The paper will conclude with a description of control algorithms which are currently in the rudimentary design stage, but may hold tremendous potential for mineral processing control systems in the next decade. INTRODUCTIONThe Canadian mining industry has a large installed milling base and many plants are run with manual or low level automatic process control. The competitive pressures imposed by the market will not allow these operations to ignore the significant increase in efficiency that can be achieved through the effective application of advanced process control. These improvements will come in the form of better quality, higher productivity and reduced costs.There have been quite a number of reports of successful applications of advanced control in mineral processing applications. As this trend continues, and more of the work is documented, the technology will be more effectively transferred to process and control engineers. It is the authors' opinion that the most difficult problems facing process control are not really technical in nature. Rather, they lie more in process control education. This extends from management, through engineering to the operators.The purpose of this paper is to provide a tutorial type overview of some of the more frequently encountered advanced control algorithms. The assumption is that the reader has a superficial knowledge of this technology. In the discussions which follow, several techniques are explored within the framework of simple process examples. Industrial examples are cited for each and an evaluation of the expected longer term potential is given."

Jan 1, 1992

By Y. Jiang, B. Li, R. Liu

"In this study, laboratory flow tests were conducted on 2-D artificial rock fracture network models containing a single intersection constituted by two inlet and two outlet branches. Three models with different intersecting angles of 60°, 90° and 120° were tested using both dye solution and distilled water. Constant flow rates were imposed on one inlet, and the flow patterns in the fracture intersections were captured by using a CCD camera. The test results were compared with the predictions made by numerical simulations that solved the Navier-Stokes equations. The results revealed that when Reynolds number (Re) is as low as less than 1, the intersecting angle has negligible influence on the flow rate of each branch and the flow patterns within a fracture intersection. As the interesting angle ? and Re (e.g., from 10 to 200) change, the normalized flow rates of different outlet branches change significantly, due to the inertial effect of fluid flow. These changes could be represented by a series of mathematical expressions involving Re and ?, which could be applied to fracture network models to improve their prediction accuracy on hydraulic properties (e.g., permeability and breakthrough curves of particles) of rock masses. INTRODUCTIONCoupled stress, flow, heat and mass transport are the corner stone subjects for many geoscience and geo-engineering disciplines, such as geological disposal of radioactive waste and geothermal energy exploitation. Many outstanding issues need to be investigated to enhance the knowledge on these subjects, and specifically more in-depth research in testing and modeling of the fluid flow in fractured rock masses is needed. In recent years, discrete fracture network (DFN) models have been extensively used to study the fluid flow and mass transport behaviors of fractured rock masses (e.g., Min et al., 2004; Zhao et al., 2011). In these models, each fracture is usually represented by a parallel-plate model, in which fluid flow exactly follows the cubic law. Therefore, comparative flow rate in each outlet branch of an intersection in these models only depends on its aperture. In reality, due to the surface roughness of fractures, the magnitude of mechanical aperture is usually larger than that of the hydraulic aperture of each fracture (Li et al., 2008; Xiong et al., 2011), and abundant flow patterns could exist in an intersection, influenced by its geometry, varying with changing Reynolds number (Re) (Kosakoswski & Berkowitz, 1999). Recent studies have also revealed that different mixing patterns might exist at a fracture intersection, bounded between streamline routing model and complete mixing model, that determine the final distribution of solutes in fractured rock masses (Johnson and Brown, 2001; Park et al., 2001). Numerical simulation has been the principal method adopted in previous studies, and the studies conducting flow tests on intersected fractures are less reported (Wilson & Witherspoon, 1976; Johnson and Brown, 2001). In this study, laboratory flow tests and numerical simulations by solving the Navier-Stokes equations were conducted on 2-D models containing a single intersection constituted by two inlet and two outlet branches, intersected at different angles. The main objective is to study the influence of intersecting angle on the flow behavior of the intersected fractures and the variations of flow patterns and fluid redistribution in each model along with the changes of the Re and the intersecting angle ?. The influence of surface roughness was not considered."

Jan 1, 2015

By Andre L. De Vegt, Cees J. N. Buisman

"For the past eight years Paques has been engaged in the development and installation of treatment systems based on biotechnological processes to remove sulfur compounds from water, air and gaseous streams. Metal and sulfate can be removed from mine waters using two biological steps:1. Sulfate reducing bacteria convert sulfate to hydrogen sulfide (H2S). The H2S reacts with the dissolved metals to form insoluble metal sulfide precipitates.2. Sulfide oxidizing bacteria convert excess H2S to elemental sulfur.Paques has designed and installed a groundwater treatment system for the Budelco zinc refinery in the Netherlands to remove metals and sulfate as described above. The system has been operating since May 1992 treating a flow of 5000 m3/d. A test program, utilizing a large scale pilot plant, will commence in November 1995 at a copper mine in the U.S.A. to remediate groundwater contaminated with sulfate and heavy metals. Biological reactor performance and selective metal recovery will be studied. Sulfur dioxide (S02) can be removed from fluegas using a combination of scrubber technology and the two biological steps. The end product is elemental sulfur. A commercial size biological desulfurization plant has been in operation since July 1994 treating 50,000 Nm3/h of fluegas. Sulfide can be removed from mining waters or anaerobic wetlands using a THIOPAQ® Sulfide Oxidizing reactor.lntroductionSulfur can be present in various water and gaseous streams in a mining operation. In many cases the sulfur compounds have to be removed because of toxicity, corrosive properties and contribution to acid rain. Mine waters can contain dissolved heavy metals. An efficient way to remove dissolved metals removal is the precipitation as metal sulfides. Paques has developed and installed treatment systems based on biotechnological processes to remove sulfur compounds from water, air and gaseous streams. These treatment systems biologically convert sulfate to hydrogen sulfide (H2S) which can be used in heavy metal precipitation. Excess H2S is biologically converted to elemental sulfur. This paper provides an overview of these newly developed biotechnological treatment systems."

Jan 1, 1997

By Samantha Beeson, Collin Poole

"This paper examines the development of two new selective flocculation techniques for recovering KCI values from low grade carnallite potash ore.Direct recovery of KCI was achieved using one of two mid-range molecular weight polymers, one non-ionic and the other strongly cationic, in conjunction with the same selective anionic dispersant. From initial response studies on pure minerals and selective flocculation tests on synthetic mixtures, investigations were extended to recover KCI values from a natural carnallite potash ore. A single-stage process achieved products grading up to 61.3% KCI at recoveries up to 85.4% for the cationic flocculant suite and up to 64.8% KCI with recoveries as high as 90.3% for the non-ionic flocculant suite, with dispersant and flocculant dosages of 150-250gr1 and 10-75gr1, respectively. These results clearly demonstrate not only the feasibility of treating such problematic ores at low reagent dosages, but also the potential elimination of desliming prior to froth flotation.The experimental results presented are considered in terms of the reagent adsorption phenomena present in the system and various aspects of floe formation and cleaning.IntroductionAs high-grade sylvinite potash ores become scarce, lower grade sylvinite and carnallite potash ores are becoming more attractive. However, these ores often contain large amounts (up to 15% by weight) of water-insoluble slimes which must be removed prior to KC! flotation, owing to their high adsorptive capacity for the amine collectors used. The slimes are generally removed by scrubbing followed by hydroclassification and any residual material not eliminated is blinded with reagents such as guar gum or starch to inhibit interference in subsequent KC1 flotation.An alternative approach used commercially in Canada by Agrium Inc. involves water-insoluble slimes flotation prior to KC! flotation. In this process, the slimes are selectively flocculated and then separated by froth flotation. Losses of KC! to the slimes product and associated brine requirements are both reported to be less than those encountered in conventional desliming, but the technique is somewhat limited in its application at present."

Jan 1, 1997

By L. W. Hamel

"Two 35 foot diameter enviro clear thickeners were tested in series as CCD units from June until October, 1978. Up to shutdown in July, we ran with automatic bed level control via the level probes and underflow pinch valves. Despite extensive efforts, we were unable to eliminate the surges created between the units by the opening and closing of the pinch valves. Early in July, the best rake speed and gap setting were determined. After shutdown, the enviro clears were run by manually controlling the pinch valves. These efforts were successful.A few mechanical problems were encountered while operating the thickeners. New units should incorporate more support for the drive coupling and a rubber feed seal. A few modifications of the instrumentation control scheme will be required before the units can be fully automated. A less sophisticated automatic flocculant addition system will accomplish the desired results. Control of the underflow withdrawal via the pinch valve should be investigated further. Our best results were obtained by keeping the feed volume to the No. 1 enviro clear constant. Surges were controlled by opening or closing both underflow valves proportionately.Capacity of the enviro clears is dependent of many variables. The ore treated during the test program was much finer than that reported on in R & D Project Report 76-02. Conditions were never steady enough to determine best flocculant dosage or addition point(s). The lowest soluble losses were obtained at very high wash rates. The underflow densities drop but the soluble losses also drop. Regression equations were developed in order to assess the effect of the various parameters. Within the range studied, these equations will predict the performance of enviro clear thickeners as CCD units on Elliot Lake ores. Our results show that the enviro clear thickeners are a viable alternative to the conventional CCD thickener."

Jan 1, 1979

By R. Nendick

"IntroductionThe Ancient Egyptians recovered gold from the mud in the bottom of ponds by having teams of maidens sit around the pond dipping goose feathers dipped in grease into the mud. The gold would preferentially stick to the oily surface and was periodically washed off to give a gold concentrate. This was a forerunner of today's flotation processes.In Greek mythology Jason and the Argonauts pursued the Golden Fleece, which was a primitive form of gravity concentrate produced when gold ore slurry was passed over a sheeps fleece. The heavy gold settled and was caught in the fleece, producing a rich concentrate that allowed Jason & Company to perform the first recorded case of highgrading. The process was a forerunner of todays shuiceboxes used in placer mining.From these simple beginnings, gold metallurgy has progressed to a state where very complex flowsheets are proposed, sometimes to perform a simple metallurgical task. Figure (i) shows a hypothetical flowsheet to identify the range of unit processes that might be brought to bear on a refractory ore. The flowsheet identifies the three primary areas of gold metallurgical operations:Ore PreparationExtractionRecovery."

Jan 1, 1986

By Gilles Landry, Mohamed Ourriban, Pierre Pelletier, Ahmed Bouajila, Claude Gagnon

"This paper summarizes the work carried out to develop and implement the gold cyanidation by size class (CSC) process, a novel concept aiming to reduce cyanide consumption.First, the authors will present the methodology and results of laboratory tests conducted to evaluate the response and the expected gains for the selected ore when submitted to the CSC processing. In the second part, focus will be on the methodology behind the CSC scheme development prior to its implementation at Sleeping Giant Mine concentrator. Finally, the evaluation of the modified circuit performance (operating since July 2007) will be addressed as a reduction of cyanide consumption by more than 30% and of free NaCN in the tailings by more than 50% is confirmed.INTRODUCTIONCyanidation is the most widely used technique to extract gold from hard rock ore. Its use of oxygen as an oxidant still makes it the cheapest process available after more than a hundred years. Unfortunately, gold cyanidation is known to be a slow process that requires high consumption of cyanide. In fact, cyanidation plants are designed with very long residence times (Habashi, F., 1967). Drawbacks of long cyanidation times are, among others, loss of gold in tailings, high reagent consumption and high capital investment and maintenance costs.Responding to their members expectations for the improvement of cyanidation process, COREM undertook a challenging R&D program covering the development of alternative concepts (processes) and the understanding and solving of mass transfer, gold passivation and process water chemistry problems. One of the interesting findings of the R&D program is a patent pending process technology based on the cyanidation by size class (CSC) concept (Côté and Ourriban, 2004; Gagnon and Ourriban, 2007; Gagnon and Ourriban, 2004).The new technology was tested at the Sleeping Giant concentrator, a plant member of COREM. The existing flowsheet was modified in order to implement the CSC process in the full-scale plant. The plant has been operated using the modified CSC based process since August 2007. Laboratory testwork was conducted prior to the industrial application in order to properly design the new process scheme. The modifications included:1) Reclassification of the grinding circuit product through an hydrocyclone2) Leaching of the coarse size fraction3) Addition of the fine fraction to the coarse leaching circuit tails."

Jan 1, 2009

By Jesse L. Duke

Outline ?Understanding the context ?The Business, political, social and legal environment ?Recipes for Success (three Ps) ?Develop effective Partnerships/relationships ?Plan carefully ?Actively Manage the ?Process? Business Environment ?Nunavut?Impressive mineral potential ?Emerging diamond industry ?Dominated by Juniors ?NWT ?Maturing Diamond industry ?Emerging oil and gas industry ?Yukon ?Alaska Highway Pipeline ?Junior-dominated exploration and development ?Growing acknowledgement in Canada of the importance of northern resources ?Shift of thinking: north-south infrastructure (vs. East-west)

May 1, 2006

By James A. Finch, Jason S. Doucet, Cesar O. Gomez

"Exercising control over the physical environment of flotation as a step towards process optimization is the driving force for characterizing gas dispersion in flotation cells, a subject of considerable research and still not fully understood. From an operational standpoint, however, there are just a few variables that can be manipulated to manage gas dispersion on a cell-to-cell basis, the most important being gas rate (superficial gas velocity Jg). Measurements in eight plants demonstrate there is often no strategy for distribution of gas to cells in a bank, i.e., there is no particular Jg profile. Two exercises where Jg profiles were set allowed metallurgical performance to be manipulated and an optimum Jg profile to be selected. To facilitate setting Jg profiles, a multi-unit device based on McGill Jg sensor technology is introduced. Possible directions for gas dispersion management are discussed.INTRODUCTIONThe earliest patents regarding the flotation process ignored the importance of air and in certain cases, steps were taken to eliminate bubbles from the system (Nelson and Smit, 2005). Rickard (1916) described a keen metallurgist who observed better than expected performance and hypothesized that entrained air was enhancing the process. Within a few years of this observation, the basic concept of modern froth flotation was developed whereby air is dispersed into slurry to induce bubble particle contact.As research into flotation advanced, the link between performance and the flow-rate of air entering the cell was established. In the first volume of the International Journal of Mineral Processing, Harris (1974) described the importance of airflow-rate and derived parameters such as the superficial gas velocity (then called the superficial airflow velocity) as being important parameters for cell design and scale-up. Mehrotra and Kapur (1974) presented research suggesting that the rate of flotation was strongly correlated to the aeration rate. McKee et al. (1976) continued to demonstrate the importance of airflow-rate linking it to the entrainment rate of hydrophilic gangue material."

Jan 1, 2006

By Roy Lindsay, Paul O'Hara, Gary Halverson

"The New Britannia Minesite is located in Snow Lake, Manitoba, 420 miles north of Winnipeg (figure 1). The mine previously operated from 1949 to 1958 extracting some 5.39 million tons of ore at a 0.150 opt gold grade. From 1959 to 1986 the property was held by Nor-Acme and Hudson Bay Exploration and Development and in 1987 High River Resources Ltd. Optioned the property, dewatered the mine and conducted a diamond drill program between the 1 780 and 2400 levels. In 1988 two companies, Nor-Acme Mines Ltd. and High River Gold Mines Ltd., negotiated an option agreement with INCO Gold whereby !NCO assumed management control of all site exploration work. During this period, a bulk sample of 10,000 tons was extracted from the 1780 level with no further exploration recorded after its removal. Both Hudson Bay Exploration and Development and INCO Gold conducted feasibility studies on reactivating the property but at a calculated capital cost of Cdn $70 to $80 million found the rate of return on their investment unacceptable.In 1991 !NCO Gold merged its interest with the assets of TVX Gold Inc. and in February 1994 TVX Gold Inc. and High River Gold Mines Ltd. entered into a joint venture partnership to develop the Snow Lake property, naming TVX Gold Inc. the operator. Upon completion of a feasibility study in April 1994 by Bharti Engineering Associates Inc., a decision was made to reopen the Britannia Mine at an established project cost of US $33 million.Project construction commenced in July 1994 with the hoist house excavation. The first concrete for the hoist house level footings was poured on August 4, 1994 and the project was completed on October 1, 1995 at a cost of US $36 million. The first gold pour took place November 4, 1995.This paper not only presents the metallurgical aspects of the operation but also describes the novel approach used to complete the design and construction of the site facilities."

Jan 1, 1996

By Elizabeth Gardiner

Tailings and water management facilities are integral components of mine and mill operations. They must be managed for the long term to ensure that safe and environmentally responsible stewardship is achieved. The Mining Association of Canada (MAC) has developed and published two manuals to provide guidance to mining companies on sound practices for the safe and environmentally responsible management of tailings facilities: ???A Guide to the Management of Tailings Facilities; and ???Developing an Operation, Maintenance and Surveillance Manual for Tailings and Water Management Facilities. The Guides were designed to help companies develop and implement tailings management systems that include environmental and safety criteria, to improve the consistency of application of sound engineering and management principles to tailings and water management facilities through their full life cycle, and to demonstrate this to regulators and the public.

May 1, 2003

By Norman O. Lotter, Dominic Fragomeni, Lori J. Kormos, Guy Comeau, Antonio Di Feo

"A performance opportunity was identified for the Raglan concentrator operation by changing the selection of xanthate from Potassium Amyl Xanthate (PAX) to Potassium Isobutyl Xanthate (PIBX). This opportunity was identified by a Statistical Benchmark Survey of the operation and QEMSCAN measurement of these survey samples, in which fine liberated pentlandite was found in the final tailings. This was confirmed by some laboratory scale flotation testwork using High- Confidence Flotation Testing. A statistically designed plant trial was implemented in 2007 to measure and confirm the performance gain. This trial design used on-off switching following a three-month reference distribution of normal operations using PAX. This layout provided both external and internal reference distributions on PAX to be established. These were used to evaluate the internal reference distributions on PIBX. This trial format was deliberately designed so as to block out the effects of autocorrelation in the operations data. In this way, small but significant metal recovery gains may be measured and proven in a plant trial. The paper describes the case study to show that this approach successfully blocks out autocorrelation in time, which is an obstacle in analysing concentrator operations data. The results showed that the PIBX had produced clear and statistically significant recovery gains for Ni, Cu, Pt and Pd. Adjusted for feed and concentrate grades, these recovery gains were: Ni: 1.00, Cu: 0.96, Pt: 5.07 and Pd: 1.90%.INTRODUCTIONConcentrator OperationsMilling and flotation, sometimes accompanied by gravity separation, are well-established unit processes. These have traditionally been used to treat ore that has been mined, producing a lowbulk concentrate containing a high percentage of the paymetal(s) in the ore mined. These concentrates are more economically treated in subsequent beneficiation processes than the ore from which they were produced.This choice of a concentration process results in a significant and variable paymetal loss to the concentrator tailing. This tailing is discarded and disposed of in an impoundment area, and has no immediate business use. This paymetal loss forms the largest loss of paymetal in the entire flowsheet by which refined, or saleable, metal(s) are produced [Cramer, 2001]. The question arises as to whether any particular concentrator is performing at its full potential, and how this answer may be determined. In a concentrator operation, there is always an ongoing performance improvement programme for this reason."

Jan 1, 2009

By C. Larsen, E. Gratch, B. Flintoff, R. Bradburn

"In 1973 Brenda Mines Limited first investigated the potential use of a process computer to aid in the development of a control system for the concentrator grinding circuit. This initial study and its results are reviewed (1) in a previous paper.Since that time the computer system and its applications have been expanded. After the initial success of grinding circuit control, a second process computer was purchased to function as a back-up device. The two processors are currently operated in a foreground-background mode which allows extensive use of the computing facility for engineering and development work as well as operator training.Because of the relative ease of expansion, the computer has been incorporated into a flotation control system as well as an electrical peak power savings program.It is the purpose of this paper to review the successful application:; of the process computer and to indicate applications which are envisaged for the future."

Jan 1, 1978

By E. Gervais

"In today's marketplace, heavy competition between materials is the norm. This is particularly true f or the base metals, which are being increasingly challenged by new or improved materials in all traditional applications. Current usage of base metals results from a combination of a metal's intrinsic properties, and technology. The future of the base metal industry rests with innovative, high-quality product development, its ability to take advantage of the results of worldwide, massive material R&D investments, and with the dynamism and effectiveness of its market development programs.The ZA casting alloys program is an illustration of the zinc industry’s efforts to protect and expand its market position in the casting field through state-of -the-art technological developments. The market potential f or these advanced engineering alloys is substantial, and their impact on traditional zinc die casting alloy consumption is particuarly important. The ZA alloys, in offering increased performance through zinc castings produced at low cost and by a wide range of moulding processes, have unlocked a multitude of new end-use applications.Following a review of the development of ZA alloys, of their key properties and of their performance characteristics, the numerous challenges that the alloys present to the zinc industry and to the R&D community are discussed.IntroductionZinc is anodic to steel and has a low, uniform rat e of corrosion; it has a low melting point, can be cast with precision , and is readily finished. In addition to its use in protecting steel and in the production of a wide range of castings, zinc is employed : (1) to produce brass, high-strength aluminum alloys and magnesium die casting alloys, (2) in the wrought state for coinage and in building products, particularly as roofing materials , and (3) as an oxide, in the rubber industry, in ceramics, glass, cosmetics, pharmaceutical products and as the starting materials for many chemicals.Zinc die castings are produced with accuracy at high speed, at low cost, are easily finished and have excel1ent mechnical properties . Car fuel economy, changes in automobile styling, competition from other materials, increased sophistication of design and miniaturization have all led to a dramatic change in the volume of zinc consumed for die-casting applications. This has been particularly notable in the United States. Throughout the 19505 and the I960s, casting was the fastest growing major use of zinc; it was firmly established, accounting for 35% of the total zinc consumption(1), By 1983, the volume of zinc being purchased for casting applications had dropped to less than 20% of all zinc consumed in the United States. In the western world(2), consumption for zinc casting application s is currently at about 15%; being nearly equal to the zinc consumed by the brass industry. Coating applications dominate with a consumption of more than 40% of the total market."

Jan 1, 1987

The common theme of these four objectives is declaration. Declaration tells the compiler that an entity exists and also provides the name and nature of the entity. Since everything you create has to be declared, you must know how to declare correctly and be able to make appropriate use of all the declaration tools available to you. This objective recognizes the importance of declaration by requiring you to know everything about Java declarations Write code that declares, constructs, and initializes arrays of any base type using any of the permitted forms both for declaration and for initialization. This objective addresses your understanding of all aspects of arrays. Arrays are the simplest possible data collection and are supported by all modern programming languages. However, Java?s arrays are different from those in other languages, especially C and C++, because they are actually exotic objects. This objective recognizes the importance of being able to make use of all the functionality of arrays. You will be expected to know how to declare, construct, and initialize arrays.

May 1, 2011

By Hiroaki Sakurai

Using batch reactors equipped with CO and CO2 gas sensor, CO oxidation over Au catalysts in room air has been investigated and compared with Pt catalysts. For both Au and Pt catalysts, the logarithm plot of CO concentration data during initial 10 min are well fitted by straight line, which mean the first order dependence on the CO concentration between 10 and 10,000ppm. The rate constant value (k) over Au and Pt catalyst generally decrease with increasing initial CO concentration above 100ppm. The value decrease especially rapidly between 100ppm and 1,000ppm over Pt catalysts, which should be due to the strong adsorption of CO on Pt. The k value over Au catalyst has become ten times or more as large as the Pt catalysts at 1,000ppm. Already for the initial concentration of 100ppm CO, the strongly adsorbed CO on Pt metal has been clearly observed by FT-IR during the reaction over Pt/Al2O3. A part of the strongly adsorbed CO has been remained on Pt after the disappearance of gas phase CO, and has gradually changed to gas phase CO2. Such strongly adsorbed species on Au has never been observed on Au/TiO2 under the same reaction conditions. These features of Au catalysts are favorable for indoor air purification.

Oct 1, 2003

By Alain Blouin, Mohamad Sabsabi, Aissa Harhira, Paul Bouchard, Greg Lithgow

"The objective of this study was to demonstrate the application of Laser-Induced Breakdown Spectroscopy (LIBS) to the continuous analysis of online monitoring of Al, Mg, Ni, Mn, Si and Fe in nickel ore limonite and saprolite slurry samples. Analysis was performed on slurry samples in air at atmospheric pressure. Two pure samples of limonite and saprolite were used. Mixtures of the two samples in varying proportions were used to build calibration curves, study the influence of solid/liquid ratio, and evaluate short and long term reproducibility. The LIBS measurement of these elements is independent of the water content (from 70-85%, the range allowed by our setup). Repeatability of the measurement and long term reproducibility (from day-to-day) were below 1.2 % and 2% respectively for all the elements studied in our conditions. The results obtained showed that an industrial LIBS analyzer could provide the chemical composition of the six elements Al, Mg, Ni, Mn, Si and Fe within 1-2 minutes.IntroductionThe metal-producing industry faces the major challenge of increasing productivity, reducing costs, and maximizing benefits from existing equipment. By pyrometallurgy, metal making involves the basic steps of charging the furnace, melting the charge and refining. By hydrometallurgy, the metal refining is carried out through the dissolution of the metal by chemical reaction and electrolysis. During refining either by pyrometallurgy or hydrometallurgy, it is critical that operating parameters be adjusted and controlled so that the chemistry of the melt or the solution is within predetermined limits. Presently, the complete turnaround time for sampling, sample transfer, analysis and communication of the results to the operators is often 30 minutes or more."

Jan 1, 2016

By H. D. Stolovitch, M. L. Lavallée

"An engineering system used to analyze and improve the performance of industrial grinding circuits has been adapted into a training program. The systematic approach to the design of training was applied in order to:Determine if training was an appropriate and effective tool for the transfer of this new technology;Define the technical content of the program;Establish program specifications based on learner and context characteristics;Design and test prototypes of the instructional modules; and,Establish a strategy for plant implementation and maintenance of the training program.This paper thus describes how a engineering system is transferred to the workplace through the use of designed instruction.INTRODUCTIONTraining can change human performance in a permanent way. It can improve productivity for the overall benefit of an operation. Organizations can therefore use training as a mean to achieve their specific goals. Training is not the solution to every performance problem. However, in many cases, it can be a very effective way to attain desired performance.The benefits of training are often difficult to assess. However, to remain competitive, organizations must introduce new products and innovative technologies. Often, they can do both most effectively through suitable training interventions.In order for the effort and investment of training to provide optimal results, two points of view should be adopted.• An overall view of the system in which training is to be applied.• A systematic approach to the design of training (Stolovitch and Keeps, 1989)."

Jan 1, 1992