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By C. Phan

This paper outlines opportunities provided for enhanced management and process control by ISA PROCESSTM technology. ISA PROCESSTM technology has the core advantage of offering the potential for vastly improved electrode handling systems. This fundamental characteristic has enabled ISA PROCESSTM technology to develop management and process control systems that are modular, minimalist in their complexity and tailored to a tankhouse operating environment. A review will be presented on the current status of management and process control in ISA PROCESSTM tankhouses covering the central issue of electrode handling as well as electrolyte circulation systems, voltage monitoring, cathode plate tracking, and product tracking. Particular reference will be made of the recent development by Xstrata Technology (XT) and their technology partners, VRT Systems, of an Radio Frequency Identification (RFID) based solution for tracking ISA PROCESSTM cathode plates. The system encompasses fixed readers which identify plates passing through the stripping machines and the use of sophisticated tracking and database software enabling the development of cathode asset management and operational strategies. The performance of individual plates and batches of plates can be tracked through a full service history.

Jan 1, 2007

By Michel Carreau

Renewable assets have large upfront capital costs but minimal operating expenses over their lifetimes. In some instances, deals can be structured so that direct capital investment is feasible, with paybacks typically within 5-7 years. In others, the burden of renewable CAPEX must be removed in order to create an attractive alternative to fossil-fuel-fired generation. Hatch has designed and oversees the construction of a renewable installation, which is financed, owned and operated by a special-purpose entity. Renewable energy is then delivered to the mining company via a customized power purchase agreement at a price that is lower than the levelized cost of fossil fuels. In this way, the mining company removes the burden of the renewable energy CAPEX from its balance sheet, thus freeing up capital, decreasing risk, and making the predictable, lower cost of renewable power more attractive than the variable cost of fossil fuels. This paper presents the above business model and success stories of hybrid power at remote sites (wind and solar coupled with diesel engine).

Aug 1, 2013

By Tao Cheng

Previous research and applications in construction resource optimization have focused on tracking the location of material and equipment. There is a lack of studies on automated monitoring of the interaction between workers and equipment for safety purposes. This paper presents a new approach for measuring the safety performance of construction personnel particularly when they work in very close proximity to moving equipment as well as static hazards such as chemical and flammable substances. A method of generating hazardous zones according to the geometric and kinematic characteristics of the considered hazard is introduced. The spatio-temporal relationships between the hazardous zones and workers? positioning data collected by real-time location sensing technology are automatically analyzed. This approach has been validated in a controlled test bed environment that simulates a construction site. Results indicate that worker?s safety performance of selected activities can be automatically and reliably measured using the developed approach. Furthermore, a heat map is generated for visualizing proximity related issues in the test bed using the computed results.

Aug 1, 2013

By G. V. Lewis

"INTRODUCTORY REMARKS""I believe we need to communicate as much as possible with the industry. I don't think that we should be a body that just goes around doing dust surveys and writing nasty letters. We should get together on these problems and try and solve them as a group. I've only been with the Department a little over 12 months. I haven't visited all of your plants. I've visited most of the major open pits and I have had a chance to observe a lot of problems that you have encountered and a lot of the problems that you have brought up this morning. I thought the best thing I could do is perhaps mention a few of the approaches to the problems that my superior has suggested to me and we have discussed in the Department, and then perhaps go over a few of the evaluating problems and what we are trying to do with our dust surveys and perhaps ways and means of improving the present setup."""

Jan 1, 1976

By Deng Yang-wu, Zhang Yan, Chen Chun-fei, Luo Xian-ping, Luo Cai-gui

This paper summarizes the ecological imbalance status of abandoned rare-earth element (REE) mines in southern China. These include large areas of vegetation damage, serious water and soil erosion, landslides, mudslides, heavy metal pollution, water pollution, soil contamination, and fluorine pollution. The causes which lead to the ecological imbalances at abandoned rare-earth mines are analyzed, such as: the inadequacies of using vat leaching, heap leaching, and in-situ leaching processes to extract REE resources; low mineral thickness and low grade of REE ore; and low utilization rates of the resource. Southern ionic REE resources are not fully integrated, with limited access and ineffective supervision of REE mining by relevant departments. The ecological recovery research for ionic-type REE mines is lagging behind, and there is no deployable ecological restoration method for REE wasteland. In the end, the following suggestions are made to improve the ecological imbalance status of rare-earth mine in southern China: develop new rare-earth extraction processes, accelerate the integration pace of REE resources, increase investment in ecological restoration research in rare-earth wasteland, and so on.

Jan 1, 2014

By G. Barbery, P. Dauphin

"In order to obtain reproducible and reproducible results in batch flotation, researchers have tried various approaches, from normalized testing, to modifying existing cells, and even designing new machines. The paper reviews the basic concepts that must be fulfilled in a laboratory flotation machine, and present the FLOTOMATEC design, which results from five years of testing and development. In addition to providing accurate measurements of air flowrate, power consumption, agitation speed, the cell eliminates most operator induced errors. Results of experiments comparing FLOTOMATEC to a conventional cell, as well as reproducibility tests are given. Introduction The use of batch flotation machines in mineral processing research and development is very common. These machines have been used for many years without almost any change in their design, instrumentation or automation. Various authors since Raffinot (1960) have criticized the available designs, especially with respect to the large errors that are introduced by the manual mode of operation. Barbery et al. (1986) have presented a review of the problems involved in laboratory testing in flotation research.Batch laboratory machines should have the following characteristics:"

Jan 1, 1989

By Eric D. Marks

Fatalities resulting from ground workers colliding with objects and construction equipment accounted for approximately 18% of the total construction fatalities experienced in 2010. Current injury and fatality measuring methods have proven to be inadequate due to their use of passive measures of safety rather than a more active approach, such as the use of leading indicator data (also called near misses) of hazardous proximity situations between ground workers and heavy equipment on construction sites. The objectives are to create and evaluate the effectiveness of a reliable algorithm for collecting and analyzing the resulting leading indicator data from hazardous proximity situations. Numerous experiments emulating typical interactions between workers-on-foot and heavy equipment are used to evaluate the proximity sensing and detection technology. Safety leading indicator data (also called near misses) generated by the proximity sensing and detection technology during the experimental trials are used to create and assess the resulting algorithm. Results from the experiments indicate that leading indicator data generated from these systems can be processed and analyzed to identify hazardous proximity situations and incidents on construction sites.

Aug 1, 2013

By D. K. Storer, W. Lee, S. Tkach

"A microcomputer-controlled multi-probe K-40 monitoring system was developed internally for the Phase II mill at the Lanigan potash mine. The K-40 probes were mounted in a variety of positions in several process streams, ranging from dry ore on a conveyor belt to brines and slurries. A description will be presented of the objectives, the equipment and the difficulties encountered in correlating results.IntroductionThe successful control and optimization of most metallurgical processes involves monitoring not only physical parameters such as flow rate and temperature, but also the chemical compositions of critical streams. Composition has proven difficult to measure on -line in industrial scale processes. However, in potash processing there is a convenient chemical parameter that has long been utilized to measure in situ the concentration of potassium chloride (KCl). Potassium has a long-lived isotope which is slightly radioactive. K40 decays by beta elimination to Ca40, ultimately radiating a characteristic gamma-ray photon. This gamma emission when detected by scintillation counter can be used to estimate the concentration of potassium in a process stream."

Jan 1, 1990

By Dave N. K., T. P. Lim

"A fast, reliable and accurate method for radium-226 determination in environmental water samples has been devised, using an alpha spectroscopic technique. The correlation between barium-133 and radium-226 in the barium-radium sulphate precipitation mechanism was studied and in the limited experimental recovery range, the coefficient of correlation was r = 0.986. A self-absorption study for various barium carrier concentrations was also undertaken to obtain the least broadening of alpha energy line widths. An optimum value of 0.3 mg barium carrier was obtained for chemical recovery in the range of 85%.IntroductionWith the increase in uranium mining activities, the migration and spread of radioactivity via various environmental pathways is of great concern. Because of its inherent biological hazard and relatively long half-life, (approximately 1620 years), raidum-226 is frequently monitored as a measure of radioactive contamination of the environment. It is, therefore, necessary to modify existing methods for rapid determination of radium-226 in environmental samples for quick corrective measures in the event of seepage, dam leakage or discharge violations."

Jan 1, 1981

By G. J. Hutchins

Precision surface mining is gaining traction in the iron ore, copper, iodine, limestone, bauxite, coal and gypsum markets. In this paper, we first address the possible improvements of a surface miner control using GPS techniques. An application in an iron ore mine in Western Australia is presented. The second item addressed is improvements of a new drum driving technique for a 100 ton surface miner. This technique involves installing a slow speed hydrostatic motor directly on the cutting drum rather than driving the drum through chain and sprockets. Details of the performance of this direct-drive versus the chain-drive are detailed. In addition to the 100 ton machine, we also present a 200 ton surface miner. This larger machine has 1600 hp (894.8 kg), and has been successfully introduced into a large iron ore mine in Western Australia. Performance of the 200 ton surface mining machine in various rock hardnesses is detailed. Some comments on the cost effectiveness of using a built-in loader versus loading with wheel loaders are included.

Aug 1, 2013

By E. Adam, B. Milkereit, M. Salisbury, L. E. Reed, G. Perron

Integrating seismic reflection, borehole geophysical, and physical rock property studies is an effective means of mapping lithological contacts and structures in the crystalline crust. At Les Mines Selbaie in the northern volcanic zone of the Late Archean Abitibi Subprovince, a high-frequency seismic reflection profile has provided the first images of deep crustal structures of this important polymetallic mine site. Physical rock property and borehole geophysical studies confirm that prominent seismic reflections can be caused by lithological contacts, faults and sulphide mineralization. At Les Mines Selbaie, the first two of these are shown by this study. Clearly identifiable reflection images from sulphide mineralization have not been demonstrated in analysis of the profile. The seismic images provide useful information about gross structure in the vicinity of Les Mines Selbaie. They can also place important constraints on the sequence of tectonic events and, therefore, can aid future deep exploration programs.

Jan 1, 1997

By A. R. Harrington

BEFORE discussing some of the technical aspects of the steam generating plants of Nova Scotia Light and Power Company, Limited, it might be of interest to go back through history and see the development of steam generation in this public utility. Back around 1902 Nova Scotia Light and Power Company, Limited, had three slide-valve engines in-stalled at its Water Street, Halifax, generating station for a total capacity of 1,800 kilowatts. The plant remained at about this size until 1910 and in 1911 a 2,000 kilowatt steam turbine was installed to raise the total capacity of the plant to 3,800 kilowatts. In 1916, a 3,000 kilowatt turbine was installed and one of the slide-valve engines was removed to make a total plant capacity of 6,200 kilowatts. The total demand in the Company's service 8rea was at that time 4,000 kilo-watts.

Jan 1, 1958

By Randy McMeekin, Chris Twigge-Molecey, J. Peter Blake

The business objectives of a metallurgical project determine targets and constraints, such as the range of products, production capacities, in-service dates, and capital and operating cost parameters. Permitting is usually left to the project team, as are decisions regarding site location, technology, and construction approach. Success requires an orderly methodology, represented in this book by front end loading (FEL) phases: FEL1 examines several alternative approaches; FEL2 ranks and eliminates less economically or technically attractive options; and FEL3 develops the preferred option to the point of major permit completion, with defined scope, schedule, and cost to submit for approval to proceed with implementation in FEL4. Working through FEL1, FEL2, and FEL3, the project definition improves, estimates become more accurate, and project risks are reduced. The project design basis at the end of FEL3 is the control document for project implementation in FEL4.

Jan 1, 2015

By L. Gutierrez, M. Pawlik

The rheology artificial mixtures of bitumen with fine quartz of varying bitumen content, as well as actual oil sand ores, was investigated under different physicochemical conditions (pH, temperature). All rheological measurements were conducted using a Haake Rotovisco VT550 rotational viscometer, connected to a fixture specifically designed to measure properties of settling suspensions. It was found that at low bitumen contents (1 %, wt.) the pH of the slurries was the most important parameter that controlled the rheology of quartz-bitumen slurries. At higher bitumen contents (10%, wt.), it was a combination of high temperature and high pH that gave the lowest apparent viscosities and yield stresses of the model mixtures. These model observations correlated well with the rheology data obtained for slurries of actual oil sand ores. The overall results were discussed in terms of aggregation-dispersion phenomena between bitumen and mineral particles.

Jan 1, 2009

By P. E. Cavanagh

FOR THE PAST seven years Mr. W. Simpson, Chief Mechanical Inspector for the Nova Scotia Department of Mines, has carried out exhaustive field trials of non-destructive inspection equipment in the coal mines of that Province. This work has demonstrated the usefulness of a number of types of non-destructive inspection when used for periodic inspection of hoisting and haulage equipment in the coal mines of Nova Scotia. As a result, the Dominion Coal Company has instituted a programme of regular preventive maintenance inspection ?by a special staff of qualified and trained men. The purpose of this present paper is to describe how non-destructive testing techniques are used on ropes, axles, couplings, and other hoisting and haulage equipment, how these methods are being used in other industries, and the expected benefits from intelligent and properly organized use of these techniques in the coal mining industry.

Jan 1, 1956

By Joseph Sawicz

By now, the concept of remotely controlling heavy equipment in underground mines has become commonplace. Personnel safety is the biggest justifier for remote control, followed by an inherent cost saving (in certain cases) when wireless video is added to the mix. There are a handful of vendors targeting this need, and for years the mines have remained loyal to their brand. But as the number of remote-control related accidents and maintenance costs increase it forces our industry to take another look at this commonplace concept. And as the blinders are taken off, the mines are getting the revelation that not all remote control systems were created equally. This paper highlights the differences between various remote control systems, and then moves into an in-depth look at HARD-LINE?s package which drastically cuts maintenance costs, and also provides a solid investment toward full Tele-operation.

Apr 1, 2005

By W. A. Lang

"IntroductionCARBONIZATION, gasification, and chemical utilization of coal are interrelated topics, which makes it difficult to review one without indicating its connection with the others. Hence, in Progress in Coal Technology, Series No. 5: Carbonization, reference was made to gaseous products recovered in the carbonization of coal, and .to a number of chemicals made from the tars, light oils, and ammoniacal liquors which are by-products of coal carbonization.In this, the sixth paper in the review series, prime consideration will be given to the complete gasification of coal to give a fuel for domestic industrial, or power purposes and a synthesis gas suitable for the manufacture of gasoline, Diesel oil, and chemicals. The hydrogenation of coal, an alternative source of liquid fuels and of chemicals, will be reviewed, as will be a number of processes for •the recovery of chemical products from coal by extraction and chemical treatment."

Jan 1, 1952

By A. D. Akerman, D. D. Young, G. R. Baiden

The development and maintenance of underground roadways are increasingly important aspects of the modern mining process. With the trend toward automation and track-less mining, roadbeds capable of with standing increased wheel loading have proven necessary to maintain high vehicle speed and reduced maintenance costs. Concrete has been used successfully on some roadways in order to obtain the required characteristics. However, this solution usually involves unacceptable expense. The objective of the Road Router project was to create a drift floor profiling machine capable of cutting a smooth surface out of the existing rock floor of development drifts and ramps. This surface would provide a durable, high strength, low rolling resistance roadbed that would allow for reduced operating cycle times and lower maintenance costs of scoops and haulage trucks. The Road Router has the potential to offer an alternative to concrete with substantial cost savings.

Jan 1, 1997

By A. Ashrafi

The electrochemical deposition of polypyrrole coating on different pretreated aluminum-alloy 7075 substrates was carried out using cyclic voltammetry, The pretreatment of specimens consisted of mechanical polishing and/or electrochemical etching, In the latter case, an aqueous solution of phosphoric acid and ethanol was used, The electrodeposition solution was 0,25 M pyrrole and 0,1 M oxalic acid in double-distilled water, The cyclic voltammetry scan rate used was 700mv/s, Morphology of the coatings was examined using scanning electron microscope (SEM), Using the Tafel experiment, corrosion resistance of the coated substrates was investigated in 0.1 M NaC1 solutions, Results obtained revealed that electropolymerization of polypyrrole on 7075 aluminum alloy would increase the resistance against corrosion in 0,1M NaC1 solution, Also it was observed that, compared with mechanical polishing, electroetching pretreatment would be more effective.

Jan 1, 2005

By A. Warczok

The mechanisms and kinetics of copper oxidation and reduction have been investigated in small scale thermal gravimetric experiments as well as in laboratory pilot scale, packed bed reactors. With blister copper flowing gravitationally down through a packed bed of ceramic particles, counter-current to low oxygen containing combustion gases, the rate of oxidation was found to be very high due to the large surface area created. Similarly, reduction by flowing copper through a packed bed of charcoal lead to rapid de-oxidation. Based on these laboratory measurements, fundamental rate data have been obtained. Modeling of industrial sized packed bed reactors using the laboratory results, opened up the possibilities of developing a new, very intensive, continuous process for copper fire refining. The developed mathematical model together with a computer process simulator, allowed for the design of the industrial-pilot installation to be built and tested at the ENAMI Paipote smelter in Chile.

Jan 1, 2007