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By J. R. Mackie

Reserve Mining Company, the first large-scale taconite pellet producer in the United States, mines it's crude ore at the Peter Mitchell Mire located on the eastern end of the Mesabi Iron Range near Babbitt, MN. The ore is processed at Reserve's beneficiation plant on the north shore of lake Superior at Silver Bay, M. The mine and plant are linked by a 47 mile, double track, railroad which is owned and operated by Reserve. (see Fig 1). At rated capacity, the mine can produce 33 million It/yr of crude ore, 15 million It/yr of waste rock and 1.0 - 1.4 million yd3/yr of glacial till stripping. Haulage of all mined material is accomplished using trucks. Ore is transported by tractor-trailer side dump units which have capacitys ranging from 83 to 110 long tons. Waste rock and glacial till is transported in end dump units of 50 to 120 LT capacity. Loading is accomplished by 11/13 yd3 power shovels and 7/10 yd3 front-end loaders.

Jan 1, 1985

By Changyoon Kim

Technological advances in mobile systems, such as smartphones and tablet computers, provide engineers with new opportunities to enhance the current facility management processes. Equipped with powerful system processors, touch screens, and wireless communication capabilities, mobile systems enable the experience of omnipresence of facility information. Building information modeling (BIM) also enables improvements in facility management. With an advanced data structure and visualization capacity, BIM can be used in numerous applications for facility management. This study aims to incorporate the strength of mobile systems and BIM in facility management. The proposed system, which utilizes smartphone technology, allows engineers to conduct facility management functions, such as maintenance planning, inspection, and assessment, irrespective of a user?s location. The integration of building information modeling in a system provides detailed visual information of the building components. A case study was conducted to verify the applicability of the mobile system in terms of the hardware functions, system design, and user interface. This proposed system, with its study results, provides a guideline as to how mobile systems can be effectively integrated with BIM for improved management of facility information.

Aug 1, 2013

By Carla Lupi

Zinc electrowinning from sulfate solutions is the traditional industrial method to produce SHG zinc. Over the past few years several efforts have been done to improve process efficiency in order to reach high productivity with low energy requirement. The latter aim can be pursued both by means of a hard purification of the electrolyte and reducing the anodic voltage. This work is a comparative study of the results obtained in several previous researches on zinc electrowinning from both sulfate and chloride solutions. Zinc electrowinning tests on industrial sulfate solution have been carried out by using Pb alloy anodes and by adding organic depolarizers such as ethanol, acetic acid or ethylene glycol. Experiments on chloride solutions, obtained by purification of zinc exhausted electrolyte, have been performed by using DSA anodes and by testing the effect of additives such as TEACI and TBAC\. Comparing the best results obtained with the two methods it can be highlighted that a high quality zinc is electrowon in both cases with comparable energy requirements.

Jan 1, 2000

By Pual M. Tyler

BLIZKRIEG tactics in the present war have consumed metals on such a profligate scale that some of the best-laid procurement plans for civilian and military needs of even a year ago seem in retrospect incredibly meager. Conservation of raw materials has reached an all-time climax in Germany, where metals are worth more than human life and throwing away an empty toothpaste tube may be legally punished by death. Even the United States and the British Empire, proud masters of nine tenths of the world?s known mineral reserves and processing plants, are being driven to metals and feverishly expanding production facilities that not long ago were deemed overbuilt. After the war is over and inevitable postwar readjustments are completed, it is reasonable to expect that purchasing power ? or at least the ability to procure the comforts and luxuries of life ? will be distributed among vastly larger population than ever before, accelerating the rising trend in demand for industrial raw materials in ever greater quantity and variety.

Jan 1, 1942

By R. E. Wagner

Consistent increase has been the mark of North American potassium (K) consumption. In 23 of the last 25 years there was upward progress The pace of usage has quickened in the past three or four years This, together with a predicted accelerated future demand, has created unprecedented interest -and activity in the potash industry. Potassium enjoyed a ninefold increase in consumption from 1940 to the present time in North America (Figure 1). Since 1950, it increased from just over a million tons of potash (K20) annually to nearly three million tons in 1964. World-wide usage exclusive of mainland China is now about 10 million metric tons. Some predictions call for another doubling in consumption in the next 10 to 15 years, About 20 percent of the four million tons of K20 produced in North America is now exported overseas and this percentage is likely to increase in the years ahead. Ten years ago, exports represented only 3-1/2 percent of total K2O production from this continent.

Jan 1, 1966

By Renn Oler

Corrosion can often cause significant strength reduction and failure of steel rockbolts, thus demanding continuous rehabilitation and posing challenges to underground mines in maintaining long term ground support. The mining industry has traditionally applied galvanized and epoxy coatings for protection of ground support and reinforcement in corrosive environments due to cost considerations. However, under a harsh and corrosive groundwater condition with extreme pH levels, failure of the existing coated rockbolts often results in failure and falls of the mine roof, especially in long-term mine drifts or entries. To prevent the roof falls induced by corrosive bolt failure, DSI developed a new polymer coating, called ?Obduro AP coating,? to combat harsh and corrosive ground conditions. The new polymer coating was tested in extreme conditions to identify weaknesses and was found to be capable of handling highly corrosive mine water solutions. This paper highlights the challenges faced by underground mines with corrosive bolt failure and shows that the DSI Omega BoltTM can withstand the most corrosive ground conditions when it is coated in the new, economic Obduro AP coating.

Jan 1, 2014

By F. Dutoy, M. B. Stella, C. F. Carrozza

Rare earth elements (REEs) are indispensable components in the manufacturing of high-tech devices, renewable energy technologies, and defence applications. As global demand for these elements continues to rise, there is a pressing need to optimize extraction processes for both efficiency and environmental sustainability. This study explores approaches to rare earth extraction using Ionquest® 801 and integrates a predictive modelling to enhance process understanding and optimization. We conducted a screening test varying pH process to evaluate the best extraction efficiency. Starting pregnant leach solution (PLS), solution was prepared in the lab with the following rare earth elements: La, Ce, Gd, Dy, and Υ, at 0.02 M for each element. The data obtained were used to develop empirical and mechanistic models to predict rare earth extraction yields and flowsheet. Further tests were performed by mixing specific concentrations of different extractant and/or phase modifier. Our experimental results demonstrated the effectiveness of the proposedextraction methods, highlighting improvements in both yield and selectivity. The developedmodels successfully captured the complex relationships between process parameters and extraction efficiency, providing valuable insights for process optimization.

Nov 6, 2024

By M. Akram

Stability assessment of entry roofs is an essential precursor to all underground design. Both multi-seam interaction and longwall mining can subject entries to radical changes in the surrounding stress field. Such loading changes frequently produce instability and failure in the roof, floor and pillars. Roofs are shown to be vulnerable to stress-induced failures, particularly when the load is unsymmetrical. To predict the effects of changes in stress field, roof failure conditions under increasing loads were studied using finite element analysis and body loaded photoelastic models. A large range of geologic conditions were evaluated and incorporated into the model using Monte Carlo methods. Entry analysis using the model showed the roof to be particularly vulnerable to shear with the location of the failure site changing to meet loading and geologic conditions. Results were correlated with field data to determine stress levels at which failure could be expected to occur. Based on this research a roof stability model SESAME was constructed for roof stability evaluation under specified loading conditions.

Jan 1, 1993

By Chang Wei, Zhigan Deng, Minting Li, Cunxiong Li, Xingbin Li

A direct hydrometallurgical process of extraction molybdenum and nickel from molybdenum-nickel ore by pressure water leaching without reagent was studied. The extraction of Mo and Ni from molybdenum-nickel ore by oxygen pressure leaching, which exploit the characteristic of molybdenum-nickel minerals contain high concentration amorphous sulfide which has highly active, and make the most of easily oxide to sulfuric acid and sulfate at low temperature and excess oxygen presence of the amorphous sulfide. Under oxygen pressure conditions, considerable molybdenum and almost all the nickel were extracted into solution in the leaching process. The results show that with the leaching time for 3~4h, temperature at 150o C, liquid-to-solid ratio of 2mL/g, mineral granularity of 0.074mm, oxygen partial pressure of 0.4~0.5MPa without other reagent, molybdenum leaching percentage can be over 80% and nickel leaching percentage can be more than 97%. Furthermore, about 80% sulfur in the Mo-Ni ore has been transformed into sulfuric acid.

Jan 1, 2014

By Ryo Kawarabuki, Atsushi Shibayama, Masato Kosugi, Masanobu Fujita, Kohei Mitsuhashi

An investigation on improving copper and iron recovery by removal of organic carbon and carbonaceous gangue mineral through flotation was carried out. The ore contains chalcopyrite and bornite as valuable minerals, and dolomite and calcite as carbonaceous gangue minerals. The chemical composition of the ore indicates that grade of 2.08 and 5.37 mass% for copper and iron respectively, while carbon was 3.70 mass%. The total organic carbon in the feed was recorded as 2.02 mass%. The presence of these gangue minerals is detrimental to copper and iron recovery during flotation. Therefore a two stage flotation study was carried out to remove hydrophobic carbon and carbonaceous material from ore and to improve copper and iron recovery. The objective of the study was to find effective and selective flotation conditions which can eliminate gangue minerals from valuable minerals and improve quality (grade) and recovery of copper and iron. The obtained results could be used to develop a flotation circuit for recovering copper and iron from carbonaceous sulphide ores.

Mar 1, 2018

By Alain Blanchier, Pascal Bernasconi

Blasting operations took place on Channel coast NW of France to extend Flamanville Nuclear Power Plant (EPR new generation). The closest operating reactor building was monitored by a 24 remote vibrations transducers network to fulfil, on one hand, the severe environment constraints and satisfy high degree of productivity required by the project, on the other hand. Although these requirements usually are incompatible, this challenge compelled to introduce a seismic modelling technique to optimize blast designs using electronic initiating system. The “Hybrid Seismic Modelling” (MSH) uses blastholes signatures (seismic vibrations records) which are greatly dependent on geology and alteration of rock mass, explosives, charge geometry, blast configuration, and the final excavation shape. In order to respect severe vibrations limits, excavation layout was divided into areas with specific blasting modules - type and number of charges, single charge, initiating sequence. Thanks to this technique, it has been possible to reach lowest blasts vibrations levels and a better productivity compared to classical blasting operation at the same location in the past. After the modelling method presentation - principle and use precautions, technical improvements are reported.

Jan 1, 2008

By Farrel W. Lytle

Instrumental analysis has become an indispensable tool in research and production of the rare-earth elements. This development can be attributed mainly to a combination of two factors--the marked chemical similarity of the rare-earth elements, which excludes classical methods of analysis, and the speed and accuracy of instrumental-analysis techniques. With continued improvements in methods of producing high-purity rare-earth elements, keeping pace instrumentally is becoming much more difficult. Accordingly, greater emphasis is being placed on improving instrumental limits of detection and accuracy. The methods employed most frequently for determining impurities in rare-earth elements involve use of the optical-emission spectrograph (3, 4)4/ and the spectrophotometer (9). Although numerous X-ray-emission spectrographic methods (6-8) have been developed for analyzing rare earths, these techniques have not included detection of low-level impurities. This investigation was conducted to find the precision and accuracy of X-ray fluorescence in deter-mining impurities in rare-earth oxides in the 0.01-to 1.0-percent-concentration range.

Jan 1, 1959

By J. W. Paul

The material that composes the roof in coal mines differs in strength according to variations in its physical nature and characteristics. Some material such as limestone and massive sandstone, (free from slits) and carbonaceous shale or bone, will often remain in place in narrow work without the use of timber or other means of support, but in wide places the use of supports becomes a real necessity. Roof material composed of shale, fire clay or small laminations of sandstone, or shale or sandstone interspersed with laminations of thin coal, presents conditions that call for timber support in both narrow and wide work. However, in narrow work such unstable roof material may be taken down until the strata assume an arch that is self-supporting for overlying firm strata such as a roof coal, a touch weather-resisting, shale, sandstone, or limestone. The proper support of the roof in roadways used for haulage or travel adds to the economy of operation by preventing delays in transportation and increases the safety of those who travel these roadways.

Jan 1, 1930

By Langtry E. Lynd

The titanium dioxide pigment industry in the United States has always relied to varying degrees on imported titanium concentrates. Dependence on foreign ilmenite was especially high (generally over 85% of consumption) until 1942, when large-scale U.S. production of ilmenite began, and has since ranged from 12% to 47%. Rutile import reliance was generally in the 45% to 80% range until the early 1960's, when increased use in the chloride pigment process raised dependence on imported rutile to over 90% in most years since 1963. Import reliance of zircon, obtained almost entirely as a byproduct of titanium mineral production, has generally ranged from about 30% to 65% of consumption. This paper will examine the history of U.S. sources of these heavy mineral commodities, and will discuss the potential U.S. future supply in view of changing industrial uses and processes and the anticipated development of new heavy-mineral-sand processing operations, such as those at Richards Bay in the Republic of South Africa and in Sierra Leone.

Jan 1, 1978

By K. J. Fair, G. Van Weert, J. E. Schneider

"IntroductionCyanidation is the principal process for extracting gold from ores . Many primary gold ores, however, are partially or totally refractory in the conventional cyanidation process.Considerable success has been achieved with new gold leaching techniques, such as intensive cyanidation, pressure cyanidation, carbon-in-leach cyanidation, etc. These techniques however, do not offer substantial gains in gold extraction from refractory pyrites.The more drastic pretreatment processes such as roasting, chemical oxidation, autoclave oxidation, and bacterial oxidation all utilize oxidation to break down the structures of pyrite and arsenopyrite. This generally renders the gold amenable to cyanidation.Comparative cost studies indicate that the oldest commercial pretreatment method, i.e. high temperature roasting, is currently the least expensive option if the sulphuric acid can be sold. It operates with air at atmospheric pressure and is characterized by fast reaction rates. For an alternative hydrometallurgical con centrate treatment method to be competitive, it too should operate with air at atmospheric pressure and with fast reaction rates. The NITROX process meets these conditions."

Jan 1, 1986

By Ashiwani Kr Gupta

The floatability of coal is affected by the presence of dissolved inorganic ions in plant process water. Water quality is characterized in terms of conductivity, hardness, turbidity and composition of oil. These quality indices are correlated with coal flotation performance for three different water named, ?R&D laboratory tap water?, ?process untreated water? from West Bokaro wahsey-2 Tata Steel, India and ?process treated water? after passing laboratory developed treatment process. The study clearly indicated that a significant quantity of clean coal is being lost due to poor process water quality used in the flotation process. The laboratory investigations showed that if these dissolved salts and suspended solids are reduced to even 50%, a clean coal yield improvement by minimum 5%~10% at the same ash level could be expected. Therefore, the conventional practice of water recycling though a thickener or a tailings pond needs a complete re-look. The water treatment process for recycled water has also been discussed for improving the process water quality as well as enhancement in flotation performance efficiency.

Jan 1, 2014

By N. Gritzuk

The area of Canada with which we are here concerned consists of Yukon Territory and Northern British Columbia. Generally it lies west of the coastal mountain range and access to the sea can be gained at only selected points which are relatively few. It is served by the Alaska Highway as well as a provincial and territorial system of roads permitting transport of mining products to Whitehorse in Yukon Territory. This town it the northern terminus of the White Pass and Yukon Route, which system provides a rail service between Whitehorse and Skagway, Alaska a distance of 110 miles, and thence to Vancouver, British Columbia, by the coastal Motor Vessel C. J. Rogers, a distance of an additional 890 miles. At present the service between Vancouver, B.C. and Whitehorse, Y. T. is on a fourteen day basis. The coastal vessel, capable of carrying 3,200 tons of cargo, was specially designed and built in 1955 for handling containerized cargo and general cargo northbound, and containerized and palletized asbestos fibre, and palletized lead and zinc concentrates southbound.

Jan 1, 1961

By P. M. Sullivan

A physical beneficiation flowsheet was designed by the Bureau of Mines for reclaiming and recycling metal and mineral values contained in municipal incinerator residues, and a continuous processing plant was installed. Residue samples collected from incinerators located in various parts of the country were processed at a rate of 1/2 ton per hour. Continuous screening, shredding, grinding, magnetic separation, and gravity concentration techniques were applied to produce metallic iron concentrates, clean nonferrous metal composites, clean fine glass fractions, and tine carbonaceous ash tailings. Research to develop systems for refining and upgrading the reclaimed metals and glass into marketable products is also underway. From the engineering data developed in the continuous processing plant, evaluations of the capital and operating costs for plants with capacities of 250, 400, 670, and 1,000 tons of dry incinerator residues per day were made. Research on a parallel system to separate and recover the metals, minerals, glass, paper, and plastics from raw, unburned refuse it currently underway, as are studies on the use of air classification to separate the refuse into organic and inorganic fractions.

Jan 1, 1971

By Henk van Muijen

From an interesting and intriguing scientific research topic, deep sea mining has altered into an interesting mining prospect over the last years. Ten years ago most of the focus was on geological investigations, searching for typical deep sea deposits and getting answers on where we can find them and how these deposits were formed. At this moment we know much more about the interesting deposit possibilities and with our quest for minerals, metals and other materials to feed global economic growth, answers as to the technical and economic feasibility to mine these deposits are sought. This is not a new phenomenon as we already witnessed such question late 1970?s and early 1980?s. Most of the focus was on mining manganese nodules and brines in the Red Sea driven by the report of the Club of Rome that predicted shortages in near future at that time. Development went different, but later in the 1990?s a rival of interest could be noticed for mining deep sea deposits.

Jan 1, 2010

By A. Yousefpour, M. Hojjati, G. Chouinard

In recent years, high performance thermoplastic composites such as PEEK and PEKK have been developed for aerospace applications. These materials offer, among the other properties, high toughness and damage tolerances. These are semi-crystalline materials and their processing can lead to different crystallinity that in turn have some impact on the final properties. The effect of cooling rate on degree of crystallinity of PEEK is studied to identify the processing window for manufacturing. Samples were heated at the constant heating rate of 20°C/min up to 375°C (above melting point) and held for 10 minute. The enthalpy of the crystallization was measured at different constant cooling rates of 0.5, 1, 2, 5, 10, 20, 30, and 40°C/min. After cooling, the samples were heated at constant heating rate of 2°C/min using modulated DSC. At temperature between 90°C to 375°C, two endotherm peaks were observed. Results suggest that endotherm peaks are related to a melting and recrystallization phenomenon of one crystal morphology. However, the second endotherm peak could be associated with another crystal structure or morphology.

Jan 1, 2006