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By Zhiqian Zhang, Chao Wu, Chao Li, Hongxu Li, Chuanqi Jiao

"Many used electronic and optical products contain cerium of rare earth oxides, but it is difficult to recover such rare earth compounds by traditional metallurgy methods. The proposed supercritical water metallurgy is a novel way, perhaps it will be very helpful for rare element recycling, but the thermodynamic properties at such special systems is not clear. In the paper the H20-CeO-CeO2 and H2O-CeO2-Ce2O3 ternary system phase diagram were produced under the pressure of30MPa with different temperature of350°C, 375°C and 400°C. The stability existing area of possible cerium compounds and different ions like Ce2+,Ce3+,Ce4+,W,HO2-,0ff ,CeOH2+,CeO+ and CeO2· were determined.IntroductionCerium is an extensively used metal element playing an important role in the rare earth elements. CeO2 is an apparently simple binary oxide with cubic fluorite structure [l]. Ce0O gives rise to a range of important technological applications because of its oxygen storage capacity at moderate temperatures as below: CeO2=CeO2.x+ X/2O2 [2]. The oxygen storage phenomenon gives ceria important technological uses in different fields as automobile exhaust purification catalyst [3-4], fluorescent powder, ultraviolet absorption material [5], polishing powder, fuel cell materials [ 6], and gas sensors, etc. The excellent properties of CeO2 nano powder make its synthesis and preparation become one of the hot spots of world scientists study."

Jan 1, 2013

By V. V. Morozov, I. S. Barmin, A. V. Tugolukov, V. V. Polivanskaya

"It was presents the results of research on improving reagent regime and scheme of enrichment of slime classes of Apatite-Staffelite ores and tailings stockpile of Kovdorsky enrichment plant. It was investigated the regularities of flocculation in the processes of thickening and selective flotation apatite-bearing ores. It was established character of the influence of flotation reagents on the flocculation process. It was shown that the sodium silicate and soda ash have a stabilizing effect by thickening of sludges. Neonol and oleic acid have a coagulating or flocculating effect. It was tested the new regime flotation, involving an initial conditioning with using of reagent - dispersants before feeding the pulp into the flotation and subsequent conditioning with reagents having a coagulating effect. The flowsheet and reagent regime for enrichment of fine-grained tailings stockpiled was developed, which providing production of standard apatite concentrate and increasing the recovery of valuable components. There are presented results of the research of activities of strong organic surfactant on solubility of colloidal form fatty acid collector and aggregate stability of fine minerals in the process of thickening and flotation. Surfactants such as Neonol have been investigated for increasing the activity of the collectors. When using the process of thickening sludge fraction with flocculant Praestol 2540 and stadial conditioning of sludge were obtained concentrates containing up to 38.1% P2O5 at recovery. INTRODUCTION A feature of the Apatite-Staffelite ores of the Kovdorsky deposit is the presence of a large number of fine mineral particles and a reduced hardness of phosphate minerals (Beloborodov et al., 2010, Tugolukov et al., 2012). Formed in the ore-preparation process, sludges are lost with a discharge in the thickening operation. Sludge is characterized by an increased content of phosphorus pentoxide (P2O5). Losses of P2O5 at enrichment of the stale tailings of Kovdorsky GOK reach 14.0%. The high losses of P2O5 caused a profound study of the behavior of thin apatite classes under conditions of thickening and flotation."

Jan 1, 2018

By Ning Yang, Sup Hong

INTRODUCTION Metal components contained in deep-seabed mineral resources are being highlighted as “energy metals”, which are widely utilized in the entire fields of energy: harvesting and generation, storage and transportation, and saving. Those are mostly trace and rare metals, and rare earth elements as well: manganese, nickel, cobalt, copper, molybdenum, tellurium, selenium, platinum, etc. Toward low carbon society, for global sustainability, the role of metals and minerals is growing up in industries of energy and transportation [1]. In this context, the production and supply of energy metals from deep seafloor have to be approached also based on sustainable development. In deep-seabed mining activity, the sustainability is focused on potential impacts on ecosystems in benthic area and water column. The environmental impacts in deep-seabed mining are caused basically by intervention in benthic zones and transportation of materials. Those are, in particular, removal of benthic habitats, generation and dispersion of sediment plumes, surface transportation of seawater and sediment, tailing from mining vessel, sound and light noises, and chemical leakage, etc. This paper is aiming at fundamental guidance towards sustainable mining of polymetallic nodules.

Jan 1, 2018

By W. de Bruijn

Differential reduction and expansion or shrinkage of hematite under the influence of intimately associated foreign oxides may be a source of stress formation and sinter degradation during blast furnace reduction. To study specific effects, synthetically pre-pared hematite powder evenly doped with 1% by weight of several elements present as oxides, was pressed into tablets and sintered at high temperature prior to reduction. Continuous thermo-gravimetric and dilatometric analyses were per-formed on the sintered tablets as these were being subjected to reduction under simulated blast furnace time/temperature/gas composition conditions up to 1183 K. These findings were coupled with observations on the microstructure of tablets removed from various stages of the reduction process.

Jan 1, 1988

The Mineral Sector Development Project, sponsored by the World Bank, has been set up to revise the legal, regulatory and fiscal framework for the minerals industry in Tanzania, with a view to attracting mining companies and investors to the country and facilitating future minerals development. One component of this project, the Environmental Management Framework for the Mineral Sector, was awarded to Wardell Armstrong of the UK and ENV Consult of Tanzania. In developing a new framework of environmental regulations, emphasis was placed on developing realistic standards which reflect local conditions and prevailing values. The main corner-stones of this approach are; effective environmental impact assessment procedures; establishment of environmental management procedures; and monitoring and auditing of companies? performance. The favoured approach involves a three-tier framework, as follows: ?Framework environmental provisions within the new Mining Act; ?Regulations covering more detailed environmental requirements ?Guidelines and/or Codes of Practice, which may in future become regulations in their own right. Careful consideration has been given, in developing the framework, to the limited resources likely to be available for implementation to the Ministry of Energy and Minerals and this has influenced the approach that has been adopted. This paper outlines the main components of the environmental management framework and discusses some of the important issues raised by these proposals.

Jan 1, 1998

By C. W. Owings

"Coal may be and has been hauled safely at approximately the same cost with permissible2 storage-battery locomotives as with trolley, cable-reel, crab-reel, or nonpermissible storage-battery locomotives. While in general, thinking mining men readily admit the relative safety of the permissible storage-battery locomotive there are some persons who question the safety of this type; however, the greatest opposition to the widespread use of storage-battery locomotives is from those who believe them to be more expensive to operate and to be more expensive in first cost than the trolley or cable-reel locomotive. Data collected during a comprehensive study- of storage-battery and wired transmission of power in some Pennsylvania and West Virginia coal mines indicate that there is but little difference between the cost of hauling with cable-reel or with storage-battery locomotives. It would appear that if this fact were mere generally known mine operators of the more progressive type would install such equipment and avail themselves of greater safety in hauling coal.The need for greater safety in haulage in coal mines is readily understood when it is considered that during the 12 month period, July 1, 1929 to June 30, 1930, trolley or cable reel gathering locomotives caused four explosions in which 407 lives were endangered, 11 persons were injured, and 30 lives were lost. Still another disaster was averted by the vigilance of a fire boss, who discovered a stratum of gas 3 feet thick at the top of an entry into which a gathering locomotive was about to enter. Other explosions not resulting in any fatality probably have not been reported. In addition numerous fires have been caused by trolley or cable-reel locomotives, and these fires probably would have been avoided had permissible storage-battery locomotives been used."

Nov 1, 1930

By A T. Spathis, K E. Leslie, K R. Blay

Many open pit mining operations seek to control blasting-related movement of ore and waste to minimise loss and dilution. Tracking the movement of ore boundaries can result in the maximisation of ore recovery and minimisation of waste sent to the mill, thereby optimising the economic performance of the operation.A novel solution for tracking the ore–waste boundary location before and after a blast uses subsurface markers placed along the boundary with all measurements and scans conducted remotely from the blast block. Upon system activation, user-operated equipment on the surface determines the three-dimensional (3D) location of the subsurface markers.The patented system concept combines two electromagnetic mechanisms, magnetic positioning and radio frequency through-rock communications to enable remote battery-powered markers, buried within the rock to be accurately located in 3D space.Field trials at a quarry have demonstrated the system can comfortably handle over 100 subsurface markers with a complete scan, including set-up, taking less than an hour. Location accuracy for each marker in 3D space is better than 0.5 m at a range up to 50 m from the magnetic source, and the system has an overall operational range in excess of 75 m.CITATION:Blay, K R, Spathis, A T and Leslie, K E, 2015. A remote, rapid and accurate three-dimensional ore waste boundary tracking system, in Proceedings 11th International Symposium on Rock Fragmentation by Blasting, pp 297–306 (The Australasian Institute of Mining and Metallurgy: Melbourne).

Aug 24, 2015

By Yukika Miyashita, Takahiro Inoue, Kenji Namikawa, Masashi Matsumoto, Junichi Koseki, Yoshihiro Terashima

"In order to construct an underground two-layer expressway branch junction structure with a height of 14.7 m and a width of 22.3 m, two shield tunnels in each layer were combined by using a non-cut-and-cover enlargement method in sedimentary soft rock. Before and during the construction work, preliminary analysis, in-situ investigations and laboratory tests were conducted to ensure the construction safety and to evaluate the deformation characteristics of sedimentary soft rock. The construction project was safely executed without any water leakage or collapse of tunnel working face. The predicted results from preliminary analysis were almost similar to the measured values. From the detailed investigation of measured results, it was confirmed that the deformation characteristic of the sedimentary soft rock was observed to a small extent as the ground deformation derived from construction work. INTRODUCTION In recent years, some newly constructed urban expressways in Japan are being planned as underground structures due to the consideration of roadside environment. The construction of such underground expressways is frequently conducted using a shield tunneling, a typical one of non-cut-and-cover methods, to prevent any adverse effect to traffic in arterial roads, operation of nearby commercial establishments, and daily lives of local residents during construction work. For underground urban expressway, the connections with existing road network on ground surface or on elevated sections are indispensable, which require the construction of an underground branch junction with large cross-section. This raises a technical difficulty regardless of the open-cut or non-open-cut construction method."

Jan 1, 2016

By Keros Cartwright

Sanitary landfilling has become one of the most widely used methods of disposing of solid refuse. A principal concern of regulatory agencies and the public itself is that landfill operations do not degrade the physical environment, including water resources, and the ground-water reservoir in particular. Ground-water and engineering geology can guide landfill operations into suitable terranes or develop measures to compensate for any natural limitations at a particular site Experience and research in Illinois suggest four activities relating to landfill disposal that warrant attention by geologists and engineers: (1) Regional delineation of favorable and unfavorable hydrogeologic conditions to facilitate planning and preliminary screening of potential landfill sites. (2) Site evaluations, with considerations of geologic materials, topography, water levels, flow systems, and local occurrence and use of water resources. (3) Re- search on aspects of the hydrogeologic environment that control effects of, or are modified by, landfills. (4) Formulation of practices in the siting, construction, and operation of landfills that prevent, mitigate, or isolate deleterious effects. The first two activities are basically in the domain of earth science, requiring the application of fundamental concepts of geology and hydrology and conventional site-exploration methods. The third activity, research, requires contributions from geology as well as other disciplines, including soil physics, sanitary engineering, and chemistry. The fourth calls for policy decisions by regulatory agencies and elected officials, using the contributions of scientists and engineers.

Jan 1, 1970

By Q. H. Liao, B. G. Monaghan

The options for designing slopes in complex geological conditions are reviewed. It is shown that modelling, especially numerical modelling, allows a degree of analysis that cannot otherwise be achieved. Examples are presented of how numerical modelling can be used to investigate fundamental aspects of rock mass behaviour. It is demonstrated that an important consequence of change in scale is that the mechanisms of failure also change. The complex failure of the footwall slope at Aznalcollar, a large open-pit mine in southern Spain, is discussed. Numerical modelling with UDEC (universal distinct-element code) has allowed the realistic simulation of displacements measured in the field

Jun 18, 1905

By L. B. Berger

In this investigation, the ampoule type of carbon-monoxide (CO) detector which is manufactured under license of U. S. Patent 1,644,014 (October 4, 1927) was tested for sensitivity and reliability. This detector was devised primarily for examining the air of manholes and sewers for possible dangerous contamination with CO before workman enter those places, but dine to the simplicity of the device it may have a more general usage for examination of atmospheres which are known or suspected to be contaminated with CO. Some of the suggested uses are the examination of the air in garages, tunnels, mines, around blast furnaces, gas plants, and in the home.

Jan 1, 1930

By L. B. Berger

In this investigation, the ampoule type of carbon-monoxide (CO) detector which is manufactured under license of U. S. Patent 1,644,014 (October 4, 1927) was tested for sensitivity and reliability. This detector was devised primarily for examining the air of manholes and sewers for possible dangerous contamination with CO before workmen enter these places, but due to the simplicity of the device it may have a more general usage for examination of atmospheres which are known or suspected, to be contaminated with CO. Some of the suggested uses are the examination of the air in garages, tunnels, mines, around blast furnaces, gas plants, and in the home.

Jan 1, 1930

By C. H. Schack, K. C. Dean

An investigation was made to devise and evaluate a flexible flotation method for beneficiating typical tactite types of calcareous scheelite - bearing ores ; these scheelite - bearing ores are available in large tonnages in deposits containing 0.2 to 0.3 pct tungsten trioxide . The objective was to achieve a high recovery of the tungsten in concentrates , containing a minimum of 10 pct WO3 , that would be suitable for chemical processing into high- quality synthetic scheelite . The principal problems encountered and resolved by bench- scale flotation tests on ore samples from five different deposits were to define the conditions and reagent combinations essential for ( 1 ) achieving selective flotation of a small amount of scheelite from a large amount of calcite and ( 2 ) controlling the effect of small amounts of calcium , magnesium , and iron salts in the ores and water used . The flotation process was evolved from batch tests and continuous runs in a pilot - scale mill with a capacity of 100 lb per hour . The flotation process comprised ( 1 ) removal of sulfide minerals , ( 2 ) conditioning the residual ore pulp with sodium carbonate , quebracho , and trisodium phosphate , and ( 3 ) rougher flotation and single - stage cleaning of a scheelite concentrate . In a pilot plant run , over 91 pct of the tungsten was recovered from ore containing 0.27 pct WO3 , in a concentrate containing 11.2 pct WO3 .

Jan 1, 1964

By M. Alvarez-Silva

The control of the amount of chromite reporting to the concentrate during the flotation of UG2 ore is of critical importance since its presence affects the downstream smelting process. It is generally reported that the main mechanism responsible for chromite recovery is through entrainment. This is reflected in analyzing the solids and water recoveries. These in turn are strongly dependent on the froth phase. In the present investigation a laboratory scale column flotation cell was used to investigate the role of the froth phase in the flotation of UG2 ore. Such a device is superior to a standard batch cell since it operates at steady state in open circuit and also allows for a greater degree of flexibility in terms of froth heights. The mass of solids and water recovered in the concentrate as well as chromite (Cr2O3) recovery by size class was determined as a function of froth height, superficial gas velocity and depressant dosage. The results showed that depressants had little effect on chromite recovery but increased the grade due to the depression of gangue minerals. A 60cm froth height always resulted in slightly lower solids, water and chromite recovery than for 30cm. Typically only 20-25 % of solids reaching the pulp-froth interface reached the launder. The relationship between solids and water recovery for a wide range of conditions indicated that chromite is mostly recovered by entrainment. Keywords: UG2 ore, column flotation cell

Sep 1, 2012

By W. C. Morgan

Recently passed federal strip mining legislation officially emphasizes that the increased coal production required by this country through surface mining is going to be obtained only with stricter environmental standards. Dozing overburden down the hillside in Appalachian contour mining or leaving drag1ine spoils in area mining is now taboo and it is now or will soon be necessary to return the disturbed land to as good or better condition than before mining. These new restrictions will create a need for new and better ways to do the job. This paper describes one approach for utilizing scrapers and dozers to strip all of the overburden and to replace that overburden in an environmentally satisfactory fashion. The objective was to do this at a lower cost than that possible with the traditional dragline system using dozers and scrapers for reclamation and topsoil handling. In area stripping, the dragline has been able to move overburden at an extremely low cost. Operating costs of 8-13¢/bcy are typical in many operations where rehandling is not required. However, the cost of leveling the spoil piles and rehandling topsoil add considerably to the low basic cost of drag1ine stripping.

Jan 1, 1977

By C. C. CONCANNON

POTASH is an essential. It is necessary as an ingredient in fertilizers or as a plant food, and certainly one of the great problems, and one of increasing gravity, is the maintenance of agricultural fertility that we may have adequate food supplies. When one thinks of potash one thinks of Germany. The first and most important deposits of soluble potash salts were found in Germany, and it was through Ger- man research and the application of a highly developed knowledge of chemistry that the value of these deposits was recognized and appreciated in the field of agricultural fertilization. The Germans knew that they had something of great value in their potash resources, not only because of the advantage derived from the extensive use of it in their own intensive farming operations at home, but also because of the pressing need for it on the part of other countries. Appreciating the economic value of this in international trade, they fostered the industry to the fullest extent and devoted much attention to well organized propaganda designed to bring out the essential need for potash of German origin throughout the world. Thus every one came to believe that potash was an essential commodity of only German origin and as such it held an extraordinary position in world trade prior to 1914.

Jan 1, 1926

By Blain CF

For all mineral resource-based companies, it is important to reach the right balance of investment between acquisition and exploration to allow the best chance of achieving long-term corporate goals. The Broken Hill Proprietary Company Limited (BHP) provides an excellent example of success from generative exploration and supports the belief that exploration can be justified, not only in terms of investment criteria, but also because it is essential to a company wishing to build a dynamic profitable growth path based on world-class deposits as cheaply as possible. BHP was incorporated in 1885 to mine a lead/zinc/silver discovery at Broken Hill. The Company has since gone through a steel development phase (1911-1965) and is now in a major phase of growth partly based on exploration success. This third phase was marked by decisions taken in the 1950's to search actively for mineral and energy resources above and beyond the requirements of the steel industry. The commercial successes of this period have been Bass Strait oil and gas, Groote Eylandt manganese, Deepdale iron ore, Gregory coal and Carnilya East nickel. In total at least 22 new resource discoveries have been made in the last 25 years, of which 11 have been developed and several are undergoing feasibility studies. A financial analysis shows that the real value of the returns seeded by discovery covers the real exploration cost many times over. Moreover, the major discoveries have had a spectacular impact on the growth and development of the Company. BHP's present exploration effort is directed towards geological targets which most frequently meet attractive financial criteria and also promote diversification from steel-related earnings.

Jan 1, 1986

By Jean-Christophe Ehrström, Fanny Mas

"A specific test set-up has been developed to study at the lab-scale the high-temperature behavior of aluminium alloys in conditions close to those experienced by thick plates during hot-rolling. A particular attention is paid to reproducing both the stress triaxiality and strain fields that exist in plate during rolling. In addition to standard ductility measurements by means of secondary tensile tests (STT), multi-step plane strain compression (PSC) tests have been performed to mimic hot-rolling pass schedules. Tool and sample geometries were adapted to allow low h/a ratios (h= average specimen thickness, a= tool width) and thus guarantee depressive stress conditions at the center of the specimen during most of the test. Such conditions resulting in porosity opening can then be used to investigate the impact of rolling conditions on damage evolution. The mechanical testing was combined with post-mortem high-resolution ultrasonic scans allowing to detect small amounts of damage and quantify its evolution as a function of processing parameters such as strain and temperature. The test set-up was validated on two 2050-type AlCuLi alloys with different susceptibilities to high temperature embrittlement.INTRODUCTION Aluminium thick plates are widely used in the aerospace industry, mainly as semi-products to be machined for internal structure parts of wings (spars, ribs) and fuselage (frame). The conversion route of such products always involves a hot-rolling step, the conditions of which (temperature, speed, pass schedule) have to be optimized to maximize both mechanical properties and final plate quality. This goal cannot always be efficiently achieved by full-scale industrial trials as (a) cost limits the number of possible test conditions and (b) it is often difficult to change one parameter alone. That is why there is a need for laboratory-scale tests able to mimic the rolling process in terms of temperature, strain rate, stress triaxiality and deformation. Most laboratory hot-rolling mills do not adequately simulate industrial processing routes, especially in terms of heat loss, deformation speed and rolling geometry (maximum roll gap vs. work roll diameter). Concerning thick plate, it is of interest to achieve both similar deformation and L/h ratio (L=arc of contact, h=mean gauge) per pass as the industrial schedule because they are simultaneously involved in damage evolution and void closure during hot forming processes (Saby, 2014)."

Jan 1, 2018

By S. J. Schatzel, J. D. Addis, V. Gangrade

In longwall mining, ventilation is considered one of the more effective means for controlling gases and dust. In order to study longwall ventilation in a controlled environment, researchers built a unique physical model called the Longwall Instrumented Aerodynamic Model (LIAM) in a laboratory at the National Institute for Occupational Safety and Health (NIOSH) Pittsburgh Mining Research Division (PMRD) campus. LIAM is a 1:30 scale physical model geometrically designed to simulate a single longwall panel with a three-entry headgate and tailgate configuration, along with three back bleeder entries. It consists of a twopart heterogeneous gob that simulates a less compacted unconsolidated zone and more compacted consolidated zone. It has a footprint of 8.94 m (29 ft.) by 4.88 m (16 ft.), with a simulated face length of 220 m (720 ft.) in full scale. LIAM is built with critical details of the face, gob, and mining machinery. It is instrumented with pressure gauges, flow anemometers, temperature probes, a fan, and a data acquisition system. Scaling relationships are derived on the basis of Reynolds and Richardson numbers to preserve the physical and dynamic similitude. This paper discusses the findings from a study conducted in the LIAM to investigate the gob-face interaction, airflow patterns within the gob, and airflow dynamics on the face for varying roof caving characteristics. Results are discussed to show the impact of caving behind the shields on longwall ventilation.

By H. C. M. Gordon

IN every co al mine the hazard of fire in the underground workings is always present. This is a natural condition, because the mineral wrought and the supports normally used are themselves combustible and because underground fires may originate in many ways. The main causes of such fires are: (1) Open lights igniting gas, wood, or the coal itself. (2) Explosives igniting gas or coal. (3) Spontaneous combustion. (4) Electric sparks or short circuits igniting gas, wood, or coal. (5) Frictional heat igniting wood, coal, or oily material. (6) Explosions of gas or coal dust igniting wood or coal. The relative importance of these causes, and others less frequently met with, varies from district to district and depends to a great extent on the equipment and supplies used, on the training and discipline maintained among the workmen, and on the liability of the coal to heat spontaneously. It follows, therefore, that open lights should not be used and that, wherever there is the least possibility of methane being encountered, only locked safety lamps of an approved type should be allowed underground. It follows, also, that only 'permitted' explosives should be used and that the it use should be confined to conditions under which they are ?permitted?. Similarly, electric equipment should be of an approved type and all such stationary equipment should be housed in well-ventilated fireproof rooms. Such rooms, as well as entries to stables and oil houses, should be provided with doors which can be easily and tightly closed and which should be constructed of fireproof material.

Jan 1, 1937