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By AIME AIME

THE twenty-second annual meeting of the Canadian Mining Institute was held at the King Edward Hotel, Toronto, on Mar. 8, 9, and 10, and was followed on the 11th by an all-day excursion to the International Nickel Refinery at Port Colborne. The meeting was very well attended and dealt with some of the most important matters, both technical and economic, that have ever come before the Canadian Institute. The question of licensing engineers is before the Canadian members as it is before our own in this country and the attitude of the mining engineers across the border is like that of the American mining engineers, opposed to the licensing of the mining. engineer, however they may feel toward the licensing of other branches of the engineering profession. It was well pointed out that such a law, had it been in existence in the last decade or two, would probably have prevented the rapid development of Canada's mines. Whereas one civil engineer can run a line of survey as well as another, perhaps, it is only a question in his case of whether he can or cannot survey. In the case of a mining engineer employed by a man with capital to invest in a development project, unless the man with the money has confidence in the judgment of his engineer the fact that he is a professional man would carry little weight in inducing a large investment toward the development of Canada's resources. It was also pointed out that although the Institute as a whole had not passed on the matter, it would probably be opposed to legislation aiming only for self-interest, but would be heartily in accord with legislation which could be shown to be for the service of the community at large.

Jan 1, 1920

By T. R. Wildeman

"At the Big Five wetland, which was built to treat drainage from a metal mine, encouraging results have attributed to sulfate reduction. Cu and Zn were reduced to below detection limits of 0.50 mg/L, Fe was reduced by at least 90% to below 3 mg/L, and the pH was raised from below 3 to above 6. The study showed that treatment was primarily through microbial processes within the substrate and that plants were not needed to insure success.Constructed wetlands can be taken through design and proofing stages, and into operations scale in a meaningful time frame for on-line acid drainage remediation. In staged design, laboratory experiments are initiated to determine reasonable substrate materials for remediation of a particular drainage. When a reasonable substrate is found, bench scale experiments are initiated as the next stage in the design. In these studies, removal efficiency, permeability, and flow are analyzed to identify candidate substrate which will support sulfate reduction and be hydraulically reasonable. Using this design method at one site, an acid drainage of pH 2.5 was raised to a pH of above 7. Total heavy metal concentrations in this drainage exceeded 900 mg/L. In the pilot constructed wetland Cu, Zn, and Fe were reduced by 99%.Determining how well these anaerobic cells operate in the winter is done at the pilot plant site in Idaho Springs, CO. It's been found that over the last four winters, those cells that emphasize anaerobic removal within the substrate have operated continuously and effectively the year round. Winter operation is aided by the fact that the water temperature of the acid drainage is always between 14 and 16° C, and the cell can be readily insulated from the cold. Activity of the sulfate reducing bacteria may decrease during the winter. However, it appears that organic complexation of metals helps to maintain low concentrations of metals in the effluent."

Jan 1, 1992

By Charles J. Kucera

Today's highly publicized issues of resource development and environmental protection are not new. But recently these issues have been played one against the other, and some would have us believe they are mutually exclusive. Why? Because modern man has realized that the shortest route to achieving economic progress is to subdue nature. He extracts mineral resources from the earth to provide the raw materials upon which other processes and services are based. But often in his search for economic progress he finds that other highly- held values (e.g., an unspoiled environment) have been violated. The natural response is a counter action - to attempt to protect nature. But this response is basically unsatisfactory because it is reactive.

Jan 1, 1979

In choosing such a threadbare subject for a paper I fear that I may in some measure be taxing your patience, yet as upon the accuracy with which the work is done depends the result of conclusions drawn as to whether a property will be profitable to work or otherwise. The subject cannot be too well threshed out, and I trust that upon certain points that have come within my own experience I may be able to give 'hints that will prevent others from making mistakes. First as to alluvial. Gold is often found from the grass roots down, often ill particular horizontal bands in the wash, but more generally concentrated either on a true or false bottom. When sampling dry ground for proposed hydraulicing I have obtained accurate results only by taking the whole of the dirt from measured shafts, stacking it as it was lifted on a tarpaulin, and putting the whole quantity through a carefully constructed box. In wet ground careful borings will in most cases give fairly correct results, but where it is possible to sink shafts, that should be done, as a guide is then also obtained as to the nature of the wash, whether it is bouldery, cemented, or free. Sampling in a face is a more difficult work in many respects than in new ground, as so many elements enter into action to spoil accurate sampling. Of course the great thing to avoid is sampling in any place where either natural or artificial concentration has taken place, and very much has to be left to circumstance and the sampler's own judgment. In passing I may mention that I have on several occasions seen diggers deceive themselves in wet ground where they were sinking and coping as best they might with water. They would take a dish of dirt from the bottom of their hole, pan it off, and take the result as a fair yield, and on the strength of it perhaps spend a lot of time and money in tail races and whereas in their sample there had been a process of concentration carried on, the movement and working in the water had caused the gold to work down, and anything like accurate estimations by the method pursued were out of the question.

"To prevent the propagation of mine explosions, the Bureau of Mines recommends:1. That all coal and lignite mines, except anthracite mines shall be rock dusted.2. That rock dust shall be distributed upon top, bottom, and sides of all underground openings of every description, to within. at least 4o feet of all working faces and the areas not rock dusted shall be kept wet.3. That the rock dust shall be maintained in, such quantity that the incombustible material in representative samples of dust collected shall not be less than 65 percent. Where methane gas is present in the ventilating current, the minimum percentage of incombustible matter in the mine dust shall be increased 1 percent for each 0.1 percent of methane.4. That when the rock dust in any area becomes caked so thatit cannot be dispersed readily as a cloud in the air, that part of the mine shall be redusted immediately.5. That the dust to be used shall not contain more than 5 percent of combustible matter nor. more than 25 percent of quartz or free silica; all of the dust shall pass through a sieve having 20 meshes per linear inch and 60 percent or more shall pass through a sieve having 200 meshes per linear inch; the dust shall not absorb moisture from the air to such an extent as to cake and destroy its effectiveness as a dry dust.6. That rock-dust barriers shall not be regarded as a substitute for generalized rock dusting.Research and experience have shown that maintenance of an adequate percentage of rock dust in all underground openings, whether gassy or not, of bituminous and subbituminous coal and lignite mines (anthracite dust does not propagate explosions) is the best means of preventing coal dust explosions. In rare instances where all fine coal particles on the floor, ribs, roof, and timbers are in a muddy condition continuously rock dusting is unnecessary.The term ""underground openings"" refers to all unsealed openings whether they contain track or not, and includes rooms, entries, crosscuts, breakthroughs, rock tunnels, slopes, haulageways, airways, and travelingways. The sealing of unused or abandoned parts of a mine in accordance with Mine Safety Board Decision avoids the necessity of rock-dusting the sealed-off openings.The kind of rock dust to be used should have the approval of the State Mine Inspection Service. Pure limestone or pare dolomite produces the best rock dust, as these dusts have low silica content, little tendency to cake, and a light color that aids illumination. To reduce tendency to cake it is preferable that not more than 75 percent of the dust pass the 200-mesh sieve. All sieve sizes are those of the Tyler screen scale. If the mine personnel is repeatedly exposed to breathing high concentrations of the dust, the percentage of free and combined silica should be as low as possible, preferably less than 5 percent. Persons engaged in the application of rock dust should wear approved dust respirators as listed in Bureau of Mines Information Circular 7030 or revisions thereof."

Mar 1, 1940

Keywords: Pyrometallurgy, zinc, electrowinning Zincor has been producing zinc since 1969 via the roast-leach-electrowinning process. It is the only primary zinc producer in South Africa, and currently supplies the entire country with zinc. The plant was built by Goldfields of South Africa, on the site of an old gold and uranium mine. Since then, the ownership of the plant has changed a couple of times, and the plant and process have also been improved. Production output has increased from around 80 000 tons per year to more than 110 000 tons per year. This was done mainly through increasing the capacity of the roasters and acid plant. Zincor produces four main grades of zinc: SHG, Zn1, Zn2, and Zn4, in three shapes: a 25 kg ingot and 1 and 2 ton jumbos. In 2005, a pre-alloy furnace was built that enabled the production of jumbos pre-alloyed with aluminium. This has allowed Zincor's customers to improve the efficiency of their continuous galvanizing lines and to lower their production costs.

Jan 1, 2006

By Guillermo Turner-Saad

"Best practice in the economic evaluation of mining projects and operations is based on the integration of geological, mining, metallurgical, environmental, marketing, economic and corporate information and strategies. Fundamentally, the economic evaluation takes into account mining, blending, stockpiling, processing, smelting, refining and marketing ore resources with grades estimated by geostatistical methodologies.Nevertheless, a realistic economic evaluation consists of a concurrent and integrated optimization process that maximizes the concentrates or products of liberated and selected ore minerals from mineral deposits. The optimum solution is obtained through a trade-off among mining, blending, stockpiling and processing ore reserves with distinct mineralogy and texture characteristics. The concurrent optimization determines both the practical mining sequence of ore reserves and the dynamic and robust mineral processing flowsheet design over the expected life of mining projects and operations.A combined risk-adverse and concurrent optimization process takes into account the spatial uncertainty of the mineralogy and texture characteristics of ore reserves. Additionally, a variety of mineral processing linear, non-linear, additive and non-additive parameters modeled spatially. The spatial uncertainty of these ore reserves characteristics and parameters has a direct impact in the expected mining sequence, mineral processing flowsheet design, concentrates or products quantity and quality, and economic value of mining projects and operations.Geometallurgical domain constrained stochastic geostatistical methodologies and multivariate mathematical models are applied for spatial uncertainty modeling of ore reserves characteristics and parameters. These mathematical models correlate the mineral processing liberation and selectivity responses of the mineralogy and textures within each geometallurgical domain. These models, in turn, are defined based on results of mineral processing and environmental testwork of unbiased and representative samples chosen for their variability. These samples are selected within mutually exclusive spatial geometallurgical uncertainty domains with similar mineralogical and textural characteristics in mineral deposits.Geometallurgical domains are defined by applying and combining multivariate statistical analysis and implicit modeling methodologies. These involve determining and constraining mineral processing liberation and selectivity properties explicitly contained in the extensive and integrated exploration drillhole database."

Jan 1, 2010

By Murray Wood, Michael Schaffer, Makat Katom

"An expert system applied to the control of mineral process unit operations is, by its nature, the site best operating practice, having been designed by the local experts in conjunction with consulting metallurgists. The “common sense” layer in a MET (MinnovEX Expert Technology) solution determines an appropriate action for the current operating conditions through a developed heuristic model of the process (expert system). The magnitude of the setpoint change that is made is proportional to the confidence that the system has in its interpretation of the current conditions (fuzzy logic). The solution is always striving to take the process to a constraint and thereby optimise the operation. An accepted limitation of the solution is that the only way the system can determine if a constraint has been reached is to exceed it and then withdraw – essentially “experimenting” with the process. By leveraging a model, which can accurately ""simulate"" the process, this restriction can be circumvented by pre-testing the set point change through a ""what if"" analysis and then modifying the solution as appropriate.At Ok Tedi, the introduction in 1999 of a MET expert system for SAG milling resulted in significant improvement in circuit throughput. Yet, with the additional inclusion of an accurate model of the process there was still more that could be achieved. Hence, in 2002 a MET Neural Network model was developed and deployed to enhance the existing expert system solution. The principal objective of this model was predicting the effect that changes in SAG tonnage and density would have on the power draw of the mill - essentially a power predictor. The results have seen a decrease in process variance with an associated increase in average circuit performance.This paper describes the methodology by which the Neural Network model was implemented, the considerations and limitations when applying this technology and ultimately the results that were achieved."

Jan 1, 2003

By John A. Mathews

RESEARCH in the steel industry, as in other lines of manufacturing, has for its principal purpose the increasing of profits. That is what manufacturing companies are for, and all departments of the organization must be so coordinated as to lead to profitable operation. To divide a payroll into productive and non-productive labor is misleading. Productive labor, in fact, is necessary labor, and non- productive labor is the labor we can get along without. One might as well say that the steering wheel is not a part of an automobile as to say that the directing minds of an industry are non-productive. Legitimate manufacturing profits in a steel company or any other company are the reward that the public pays for service rendered or risk taken. The desire for profits is the impelling motive that leads investors .to take risks and build up industries that give employment to others. Every department of a company, be it executive, manufacturing, financial, sales, or research, must contribute to the one end which brings success-profits.

Jan 1, 1921

By Scott Turner

Many of you radio listeners have probably never seen a mine . You may be glad of it, but you should not forget that there is a vast army of men in this country who not only have to see mines , but have to work in them day by day in order that you may be supplied with many of the things you need. Specifically , nearly a million men work in the mines of the United States , 700,000 in the coal mines , 110,000 in the metal mines , 100,000 in other mines and quarries , and 75,000 in the oil and gas fields . On a stormy night , the average citizen is apt to think of the perils of the seaman . Particularly in the old days before steamships , many a prayer went up " God help the poor sailor on a night like this . " At the same time , the sailormen often expressed fear for the poor landlubber , exposed as he was to the danger of falling chimneys , swaying signboards , and uprooted trees . So with the miner . Many of you may pity him , for working underground in complete darkness except for feeble artificial lighting , mining coal or ore , drilling hard rock , handling explosives , and perhaps breathing vitiated air . On the other hand , on stormy days , with rain , snow or hail falling , and with the temperature low , or on hot bright days , I have often heard miners joke about the poor fellows who had to stay " on top, " and could not get " down below" where there was no wind , where no snow fell, where the temperature was unchanging , and where a man could have his own working place , arranged to suit himself , with little interference from meddlers and with no automobiles to dodge . So do not feel too sorry for the miner . He is quite apt to be a strong , healthy , hearty person , making pretty good wages , and fairly well contented with his lot .

Dec 1, 1930

By Heribert F. Broicher

By the very nature of mineral deposits the quality of the raw material generally fluctuates and should be known for optimum processing. Early classification, for example, of limestone into road-metal grade or lime grade or of run-of-mine ores into high grade, low grade and waste as well as information for blending or for dosage of reagents are prerequisite for economic processing. Non-contact, real-time and on-line rock identification or assessment of quality parameters can be realised by introducing the analysis of laser-induced fluorescence (LIF) into the mining industry. LIF analysis is an optical method evaluating the basically known photoluminescence properties of matter, however, extending the application into hitherto unimagined fields by use of high-energy pulsed lasers and time-resolved analysis of fluorescence in the ultra-violet, the visible and near-infrared domains of light. LIF analysers and test work in a limestone quarry and a cement plant in Germany as well as in an iron ore mine in Sweden are described. First results of test work are available and proof this technology to be promissing.

May 1, 2002

By Kunihiko Takahashi, Gjergj Dodbiba, Hisayoshi Umeda, Toyohisa Fujita

"An increasing number of mobile phones is increasing the number of the discarded mobile phones. Many efforts are thus being made to collect and recycle these devices. This paper is a short introduction of the recycling system of precious metals from the discarded mobile phone, currently available in Japan. Moreover, an attempt has been made to compare the energy recovery and the mechanical recycling of plastic wastes from the discarded mobile phone. The assessment has been carried out in the context of the life cycle assessment methodology (LCA). The environmental impact of each option was assessed by calculating the following impact indicators: depletion of abiotic resources (ADP), and global warming potential (GWP). 1. Introduction In 2003, the demand for mobile phones was increased since the camera was included in a mobile phone and the 3rd generation of mobile phones was introduced. In turn, the number of discarded mobile phone is rising sharply. Generally speaking, all the metallic parts of mobile phones can be recovered and recycled by using smelting and purification techniques. The recycled materials are then used to fabricate other new products."

Jan 1, 2008

By Z. Q. Zhou

It is the first worke in design of pile foundation to determine the carring capacity of single pile, and a static loading on site is considered to be the lost derect and reliable way. All values P and settlements S induced can be plotted as a broken-line. Since soil is a kind of elasto-plastic and cohesive material, the increasing of settlements is generally greater than that of loads. Different value Pu nay be given by different tester on his P-S diagram, because of erroys in the test and complicated, characteristics of soil. The analytical method of exponential equation shown in this paper derives a specified solution. After using an exponential curve to regress values of loads P and corresponding settlements S from on-site test, coeficients A and B of exponential equation can be obtained. With this curve an ultimate carrying capacity of single pile can be determined. The resistant forces of pile shaft and pile tip can also be defined by the tangent of the calculated knee point, as it is called (tangent method). At last, an example is given to show how the ultimate carrying capacity of f 500mm bored pile is obtained with this method for a project in Kunming.

Jan 1, 2010

By S. McGinn

The Brunswick Mine Diesel Particulate Filter Study was one of several research projects initiated by the Diesel Emissions Evaluation Program (DEEP). The study was carried out at Noranda?s Brunswick Mine in Bathurst, New Brunswick by Noranda Technology Centre and Brunswick Mine personnel with the collaboration of Natural Resources Canada - Canada Centre for Minerals and Energy Technology (CANMET), National Institute of Occupational Safety and Health (NIOSH), Andreas Mayer of VERT, and diesel particulate filter (DPF) system suppliers. The study began in early 2000. Field evaluations continued for 20 months. The final report?authored by Sean McGinn?was submitted to DEEP in the Autumn of 2003.

Jan 1, 2004

By Chris G. Leach

"Abstract A seven storey Northbridge area of Perth, Western Australia presented residential apartment complex located in the an opportunity for a novel application of Cutter Soil Mix technology (CSM). The development included a two-level basement for car parking which covered the full site area. However, the basement was also required to extend under an existing single story heritage building. Soil conditions comprised 2m of fill overlying medium dense to dense sands that in turn were overlying a very stiff clay stratum at approximately 14-16m depth. The ground water table was located at a depth of approximately 1m below the natural surface level.A site boundary consisting of a reinforced CSM retention system and was designed and installed to allow the excavation to proceed to basement level. Two rows of temporary soils anchors or inclined struts were required to achieve this. A CSM support system for the heritage building was also designed and constructed to provide temporary support during excavation and permanent construction works. The brief for the contract works emphasised that it was vital that settlements of the heritage building be kept within strict limits.CSM is a relatively new introduction to the Australian construction market, using a modified trench cutter to mix a binder slurry with in situ soils, generally to form cut-off walls, retaining walls and soil improvement works. This project is understood to be first application of the CSM for underpinning work in Australia.This paper discusses the site background details leading to the decision by the client to adopt CSM technology, and the design and construction aspects to meet the challenges offered by this project.Introduction190 Newcastle St is a 7-level residential apartment complex located in the Northbridge area of Perth, Western Australia. The development includes a 2 level basement for car parking, which covers the full site area. The basement also extends under a single story heritage building, which remained in-situ throughout the building works.A site boundary retention system was required to allow the excavation to basement level to proceed. In addition, a support system for the heritage building was required to provide temporary support during excavation and permanent construction works."

Jan 1, 2014

By Darrell Gillis

Recent accidents in the United States underground Coal Mines and the on-going carnage in Underground Chinese Coal Mines has shown the danger associated with the lack of communication infrastructures in an underground environment. The US Mine Safety and Health Administration (MSHA) have introduced legislation that states all Underground Coal Mines must have two-way voice and personnel tracking capabilities by 2009. If Coal Mining companies are being forced to deal with this problem Tunneling Companies will not be far behind. This paper will examine current practices and best case technology to deal with these issues.

Jan 1, 2007

By Tiziana Apuani

The study refers to an area of about 70 km2, extended in the Italian Central Alps along the the San Giacomo Valley where different civil and mining works are present The regional geological setting is related to the Pennidic Nappe arrangement, characterized by the emplacement of sub-horizontal gneissic bodies resulting from the Mesoalpine isoclinalic folding of crystalline basements, emplaced throw East, and separated by matasedimentary cover units. The investigated geological rocks, belong to the ?Tambò?Unit, overlapped by its meta-sedimentary cover and by the ?Suretta? Unit. The tectonic contact gently dips to the E?NE. The valley, furrowed by the Liro Torrent, follows a N?S striking tectonic lineament, almost parallel to the nappe contact. A number of more then 70 sites, distributed in the studied area, were chosen and detailed structural and geomechanical field surveys were performed to characterize the rock masses, its intact rock and discontinuities. The procedure identifies the number of joint sets, their representative orientation, the set spacing, the type of movement, the amount of dilatation, the degree of alteration, the roughness coefficient, the presence and nature of infill. Rock mass quality indexes, such as the Rock Mass Rating (Bieniawski, 1989) or the Geological Strength Index (Hoek et al. 2002) have been evaluated in each surveyed site. The work is a contribute in assessing how the geometrical and geomechanical properties of the rock masses can be regarded as regionalized variables. The spatial distribution of these properties is a function of the geological and structural phenomena at which the rock masses have been subjected. The presented geostatistical analysis regards the spatial variation of the orientation of the most representative joint set.

May 1, 2009

By G. Lyle

Since its inception CEMI (Centre for Excellence in Mining Innovation) has focused on facilitating innovative solutions to the mining industry in six strategic research areas; GeoRisk, ConstructMine, ValueMine, FindMine, SustainMine and MineTech (visit www.miningexcellence.ca for details). This paper focuses on CEMI?s largest project to date, Ventilation on Demand (VOD). Energy consumption in mines can account for upwards of 40% of a mines operating cost, with a significant portion of this been consumed by the ventilation requirements. VOD provides a significant opportunity to reduce overall mine ventilation requirements and subsequently energy costs, while potentially increasing mine productivity. CEMI is currently in year 2 of an assessment of VOD, focusing on the financial, physical and equipment viability of utilizing such systems in both new and existing mines. This two year program, to be completed by March 31, 2011, is designed to systematically assess such a system to determine if and when it could effectively be applied in underground mines. The paper will describe the process by which the project was initiated, the demonstration projects established to capture data, the means to interpret the data and the modelling developed to calibrate and predict ventilation system requirements.

Oct 1, 2010

By J. R. Koehler

Although two-entry yield pillar-based gate roads supported by wooden cribs have been commonly used throughout longwalling in the Wasatch PlateadRoan Cliffs coalfield of central Utah, a three-entry yield-abutment gate road configuration was recently trialed in the Hiawatha Seam at the Genwal Resources (GRI) Crandall Canyon No. 1 Mine, near Huntington, UT. Pillar, entry, and cable bolt performance were monitored through second panel mining using a fairly extensive array of geomechanical instruments installed over a span of four crosscuts. Ground pressure and entry closure measurements confirmed that the 9.1-m-wide (30-ft) yield pillar was partially shielded from first panel longwall loads by the 36.6-m-wide (120-ft) abutment pillar, and consequently, experienced only minor yielding until the approach of the second panel face. Complete yielding of the 9. I-m-wide (30-ft) pillar occurred when the second panel was approximately 6.1 m (20 ft) inby the instrumentation site. Average cable bolt loads and differential roof sag remained low through second panel mining and tailgate entry ground conditions were excellent; however, very high ground pressures in the abutment and yield pillars, and second panel rib strongly suggest a high potential for coal bumps utilizing this gate road configuration at mining cover depths in excess of 396 to 457 m (1300 to 1500 ft). This conclusion is supported by the suspected occurrence of small coal bumps along the abutment pillar ribs, observed indirectly as fresh debris in the middle entry just behind the second face. This paper presents a case history developed from the geotechnical measurements and on-site observations of this unique application of a yield-abutment gate road configuration and cable support system in the Hiawatha Seam.

Jan 1, 1996

By R. B. Bauder

In connection with a Bureau of Mines research program on utilization of Cuban lateritic ores, a comprehensive review was made of the chemical literature on nickel and cobalt. Initially, the review had as its objective the selection, from the voluminous literature dealing with the chemistry of these two metals, of only those references to reactions that were especially pertinent, or at least closely related, to the field of extractive metallurgy. Later, the coverage was extended to include references to the techniques and plant applications of extractive metallurgical procedures for the recovery of nickel and cobalt. In this report, the period from January 1929 to July 1955 has been covered, as it seemed logical that recent literature should be of greatest value. This cutoff date was established in order that the bibiliography could be issued at an early date, inasmuch as currently much work is in progress on the lateritic ores. Later, a supplement will be prepared extending the coverage to about 1900.

Jan 1, 1957