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By K. Sun, S. A. Argyropoulos

The assimilation and the exothermic behavior of Zn-Zr metallic powder compacts into molten aluminum was studied by measuring simultaneously the temperatures inside at the centerline of the compact, at its surface, and inside the molten aluminum bath, as well as the net downward force acting on the compact. In addition, the exothermic behavior of these compacts was also investigated in an argon protected atmosphere. The temperature rise inside the compact increases significantly with the mass ratio of zirconium in the compact and to a lesser degree with the aluminum bath temperature. Experimental results on the recovery of these compacts in molten aluminum will also be presented.

Jan 1, 2008

By G. Q. Zhou, H. C. Liang, X. D. Zhao

"This study describes the strain behavior in vertical shaft lining (VSL) embedded in thick soil deposits and its application in assessment of concrete deterioration. The observed strain in VSL continuously decreased companied by a sinusoidal fluctuation due to the influences derived from negative skin friction (NSF) and temperature. The increase in strain increment between peak and trough at each year and compressive strain level as the servicing time continued and VSL depth increased implies that the concrete strength was attenuated, and this attenuation was significantly dependent on the existing compressive strain level in VSL. The reliability of the proposed approach was validated by Schmidt Hammer Technique (SHT) – based concrete strength, and is applicable in concrete assessment and then fracturing prediction of VLSs in thick soil deposits.Concrete strength, Field monitoring, Strain behavior, Vertical shaft liningINTRODUCTIONOver 100 VSLs in Southeastern China subjected to an unpredictable fracturing as shown in Figure1, and there are over 1,000 VSLs embedded in thick alluvium su?ering from challenges of damaging and potential fracturing (Cheng, Yang, Zhou, Li, & Hu, 1993; Zhou, Cui, Lv, Huang, & Chen, 1999; Li & Li,2005). Therefore, a reliable assessment of these VSLs is significant to the normal servicing of mine shafts and the recycle of underground space when these mine shafts were closed.The continuous increasing of NSF induced by the drainage of water–saturated deposits well interpreted such extensive fracturing phenomenon, and it is universally regarded as the governing indicator to determine the VSL stabilization (Cheng et al., 1993; Zhou et al., 1999). Based on this recognition, the fracturing prediction and VSL strengthening according to the field monitoring on hydrogeological characteristics, servicing environments, and mechanical behaviors of VSL were carried out (Zhao, Zhou, Zhong, Zhu, & Liang, 2009; Liang et al., 2009; Xie, Lv, & Wu, 2014). As known, the compressive strain level in VSL and the in–situ strength of VSL concrete were the main factors to perform such fracturing prediction. However, the existing studies in literatures were limited to the strain accumulating or releasing behaviors (Zhao, Zhou, Zhao, Kuang, & Hu, 2017), and lack of considering the VSL concrete strength and its attenuation. In this reported study, the in–situ monitoring data on the strain in typical VSLs and the VSL elevations between 2004 and 2014 were initially analyzed. Then, an observed strain behaviors–based approach was developed to quantitatively evaluate the VSL concrete deterioration."

Jan 1, 2019

By Bill Charbonneau

Lumen, lm The measurement unit of light emitted by a light source 60W incandescent840 lumens 32W T8 linear fluorescent3200 lumens 54W T5HO linear fluorescent5000 lumens 400W metal halide24,000 lumens

Oct 1, 2010

By M. C. Walton, W. Roelofs

ABSTRACT: In most cases, a refractory repair involves dealing with used refractory linings above shoulder height, defining these as overhead refractories. This paper details a method of personnel protection involving a low-pressure inflatable balloon system, installed to prevent the dislodgement and freefall of in-situ refractories. This system has been successfully applied to numerous types of vessels in the process industries in the last three to four years. This paper, prepared for the CIM Conference of Metallurgists held in Vancouver, British Columbia in October 2010, outlines details of the system and gives examples of successful applications.

Jan 1, 2012

An optimization process is described that can be systematically applied by mine planners to produce life-of-mine schedules aligned with their strategic targets, while maximizing the net present value of the mining operation. The software tool employed uses heuristics and an evolutionary algorithm to generate life-of-mine schedules of production and development activities. Generating such schedules is typically a very difficult task due to the large number of operational constraints that must be respected, and the vast number of alternative schedules; as a result the value of the mining operation can be compromised. With an expansion at Newmont?s Leeville mine in Nevada, the mine planners were given the task of producing feasible life-of-mine schedules with significantly increased production rates. Their initial efforts indicated that it would be a considerable challenge to generate such schedules in a timely manner. By systematically applying the proposed optimization process, the mine planners were able to generate optimized life-of-mine schedules with the desired production rate.

Aug 1, 2013

By T. Donkin, B. Patterson, M. I. Guthrie, J. T. Ross

"Interest in the use of particle-based ore sorting has increased significantly with recent advances in sorting technologies and higher capacities per unit. Particle-based ore sorting has the potential to provide great value in processing lower grade ores from mines while delivering higher grades to the mill, as well as in upgrading waste rock into ore. Typically the focus is on the amenability of the ore to ore sorting and associated reductions in energy, water, and consumables utilization. However, layout significantly affects the installed cost of a processing plant, and the impacts on layout from fitting an ore sorting circuit into the plant plan need to be carefully considered. This paper examines processing plant layout considerations that play an important role in ore sorting projects, including additional crushing and screening requirements, transport of rejected material back to the waste stockpile (mine fleet requirements), and effects on the processing plant footprint. ¦ KEYWORDS Cold climates, Ore sorting, Plant layout RÉSUMÉ L’intérêt porté à l’utilisation du tri granulométrique du minerai a considérablement augmenté au vu des récents progrès réalisés en matière de technologies de triage et des capacités supérieures par unité. Le tri granulométrique du minerai offre une plus-value intéressante en termes de traitement du minerai à plus faible teneur extrait des mines ; il permet par ailleurs l’acheminement vers le concentrateur de minerai à plus haute teneur et la revalorisation des stériles dans le minerai. On met généralement l’accent sur la susceptibilité du minerai au triage et sur les réductions connexes en termes d’utilisation de l’énergie, de l’eau et de biens consommables. Cependant, l’aménagement physique de l’équipement a une incidence non négligeable sur le coût installé d’une usine de concentration, et les répercussions sur l’aménagement de l’installation d’un circuit de triage du minerai dans l’usine doivent être soigneusement examinées. Cet article étudie les considérations relatives à l’aménagement de l’usine de traitement qui jouent un rôle important dans les projets de triage du minerai, et notamment les exigences supplémentaires en matière de concassage et de criblage, le transport de matériau résiduel jusqu’à la pile de stockage des déchets miniers (nombre de camions requis dans le parc minier) et les effets sur l’empreinte de l’usine de traitement. ¦ MOTS CLÉS aménagement de l’usine, climats froids, triage du mineraiINTRODUCTION Ore sorting has been practised throughout history. An early report by Agricola in 1556 documents how metallic and non-metallic minerals were extracted from rocks by laboriously breaking them with hammers and picks and hand-picking selected material with higher grade (Hoover & Hoover, 1950). The concept has not changed, but sorting technology has evolved significantly over the last 20 years"

Jan 1, 2019

By Ken Musgrave

"A program is described that helps managers and supervisors control maintenance more effectively. Work- order generation, preventive maintenance, repair parts inventory, planning and scheduling, reporting, analyzing costs, printing purchase orders and other functions are covered. Flexibility often permits integration with other programs such as payroll, cost accounting and materials management.The Role of MaintenanceMaintenance provides a service to allow the rest of the operation to do its job effectively. Its success should not be measured by maintenance cost alone, but also by its effectiveness in reducing downtime and maximizing production. It can make sense to spend more maintenance dollars if this results in an even greater contribution from increased production.The Cost of MaintenanceIn mining companies, maintenance costs can be as much as half of operating costs. Maintenance has generally not been given the management attention that an expenditure of this magnitude deserves."

Jan 1, 1986

By K. Fujita, T. Kikuchi, Y. Sakamoto

Ceramic fibers were classified as a category 2 carcinogen by The European U legislation. Therefore we developed non-fibrous insulating castable which utilizes n porous aggregate, which is composed of Calciumhexaluminate. Although at beginning we applied alumina cement as binder for non-fibrous insulating castable, kind of formulation had a poor resistance to spalling. We developed non-fibrous insulating castable without alumina cement. This solved a problem which pre\ formulation had a poor resistance of spalling. We applied a new non-fibrous insub castable for reheat furnace in steelworks, then we could achieve good result which condition equivalent to ceramic fiber insulating castable.

Jan 1, 2004

By G. P. Gormley

"Future open pit metallurgical coal mines in western Canada will be developed in complex geological environments. The success of these operations will be influenced by the mine operators' ability to prepare accurate mine plans and to predict and, subsequently, 10 control both out-of-seam dilution and coal recovery. Quintette Coal Limited has been mining its tightly folded and severely faulted Mesa depo sit at annual rates of up to 9 Mt of raw coal, since October 1982. Ongoing development drilling combined with continuous utilization of blast hole information, has been required to achieve an acceptable geological data base for short range mine planning. Thrust faulting has been a primary geological cause of difficulty in selectively mining waste and coal, which has resulted in higher than expected dilution in plant feed. The same geological phenomenon has also increased reserves by 6.3% and allowed for expanded mine plans to include a lower thrust plate, ultimately doubling the mines original reserve base. This paper illustrates the geology of the Mesa deposit and the type of work involved in its interpretation. Regional GeologyThe Quintette Coal Limited (QCL) property is located in the Peace River Coal Field of northeastern British Columbia. In this area, northwesterly-trending folds of the Rocky Mountain foothills are commonly cut by multiple, low-angle thrust faults, which dip to the southwest. The Lower Cretaceous Gates Formation, of near shore continental origin, contains 5 to 7 mineable seams of medium volatile bituminous metallurgical coal (Figs. I and 2). These seams normally range in thickness between 0.75 m and 9.5 m and have an aggregate thickness of between 15 m and 22 m."

Jan 1, 1988

By A. Diaz, Minera Los Pelambres, C. G. Salinas, G. Leinenweber, F. Diaz, D. Rojas, R. Bernal, O. Jimenez

"Los Pelambres Mine (MLP) is located in the IV Region of Chile, a semi-arid region where water plays a key role in operations as a scarce resource and is vital for the sustainability of human life, animals and ecosystem. The conventional flow meters installed on pipes at MLP can fail to provide an accurate measurement due to corrosion and/or fouling on the inner wall or presence of elements in the water such as acids, salts and suspended solids. Conventional flow measurement methods require the inner diameter to be known, however it is not always possible to assess its real value due to scaling, fouling, corrosion, etc. Here we present a novel methodology to solve these problems, which consists of the measurement of flow by a method that does not require the internal area of the pipes: the fluorescent tracer dilution method. In addition, the fluid velocity can be determined by the transit time of a radioactive tracer method. With the flow rate and velocity, the equivalent area is determined and thus the equivalent internal pipe diameter as well. This methodology was applied in a recirculation pump station, for mineral processing from the El Mauro tailings dam.This work demonstrated adequate correlation between measurements from fluorescent tracers and velocity measurements from radioactive tracers, both of which lead to the assessment of the internal diameter of pipes with scaling. The results of both methods disagree with the data provided by the flowmeter installed on the line due to its miscalibration. This information is useful in validating and correcting the information provided by online flowmeters of all water and solutions transport processes in filled pipes.INTRODUCTIONPresently, the need to optimize water resources is increasingly ever important, due to various reasons such as water scarcity, community empowerment, an increased use of water for mining processes and environmental considerations. Taking into account those main considerations, Los Pelambres Mine decided to focus on water conservation to avoid losses of this vital element. They decided to demonstrate that all of the systems that used water (flow meters, pipes, pumping stations, lagoons, etc) were in good condition and that no evitable loses of this important resource occurred. A plan was proposed to conduct a “hydraulic assessment” of fluid flux and water speed at different points and courses at the mine, with the purpose of obtaining hard data to support, verify and correct the information provided online from specific instrumentation dedicated to those purposes. The final goal was to manage the water resource basin in a sustainable way, based on cross-checked information. The chosen points are representative of the processes present in the mine, such as recirculating water stations at different operating conditions and surface water courses, where the fresh water capture systems operate."

Jan 1, 2016

By A. F. Matheson

"The Jellicoe is the most westerly mine in the Little Long Lac area with a record of gold production. The property is largely covered with overburden and the ore deposit was found by diamond drilling along the projected strike of a gold bearing zone at Magnet lake 1 ½ miles to the east on the property of Bankfield Consolidated Mines, Limited. In 1940-41 Jellicoe mined the whole orebody of approximately 14,000 tons, recovering 5,620 ounces of gold.The vein is in light-coloured greywacke. A mile-long dyke of fine-grained quartz feldspar porphyry 5 to 10 feet in width lies 100 feet south of the vein. A similar, even longer dyke lies 700 to 800 feet north of the vein. Some narrow diorite dykes are also rather closely associated. The porphyry dykes are gold bearing, but not ore. The vein material is quartz and silicified and brecciated greywacke. Mineralization consists of native gold, pyrite, arsenopyrite, and some sphalerite."

Jan 1, 1954

By M. M. Williams

ALBERTA has been generously endowed with oil, natural gas, coal and water power, thus giving power producers a wide choice in the type of plant and fuel which can be used. Therefore, with such a variety of energy sources to choose from, why was coal selected as the primary fuel at Calgary Power's Wabamun steam plant? This part of the paper will cover the circumstances that led the Company to decide in favour of coal. The second part, to be presented by C. F. Doerr, will describe how the Wabamun coal mine has been developed to supply the large fuel requirements of the power plant. Before considering the Wabamun plant, we require a general under-standing of? the Company's electric system and load. Power is fed into a 5,100-mile high-voltage transmission grid from eleven hydroelectric plants and from the Wabamun steam electric plant. These plants have a combined generating capacity of 820,000 horse-power. Of this total, the hydro

Jan 1, 1963

By Dan Zou, Ji Chen, Deqian Li

"Bayan Obo mixed RE concentrate is the largest RE source in the world. RE elements occur dominantly in bastnaesite and monazite. This paper describes a clean and green technique for processing Bayan Obo mixed rare earth (RE) concentrate. A two-step oxidation method can lead to the effective recovery of REs, thorium (Th), fluorine (F) and phosphorus (P). Ce has a property of valency change, enabling the separation of it from other RE(III) elements. Making use of the interactions of cerium (IV) (Ce(IV)), F and P, a new extraction system was created to separate Ce(IV) effectively from other RE(III) while recovering F, P and Th by complexing F and P following the oxidation of Ce(III) to Ce(IV). The method includes two parts. Firstly, bastnaesite is oxidized by air roasting and sulfuric acid leaching. And then a first leach liquor containing Ce(IV), F and P is obtained. Secondly, monazite was converted into REhydroxide through alkaline attack and then Ce(III) in the RE-hydroxide was oxidized into Ce(IV) by wetair oxidation. After sulfuric acid leaching the oxidized RE-hydroxide, a second leach liquor is obtained. The two parts of leach liquor containing Ce(IV), F and P are then extracted by Cyanex923 to obtain CeO2, CeF3 and CePO4 based on the complex of Ce(IV) with F and P. The raffinate was further extracted by the primary amine N1923, and Th-product was recovered as ThO2. The RE elements recovery yield during the whole process is greater than 92%. The new technique not only provides a new way for Bayan Obo RE ore utilization, but also avoids resource waste and environment pollution.INTRODUCTIONRare Earths (REs) refer to lanthanides, including scandium and yttrium. Owing to the similar structure and property of RE(III), it is difficult to separate them from each other, especially for the adjacent elements. According to the United States Geological Survey, in 2010, the whole world has about 142 million tonnes of rare earth reserves. In that, China ranks the second with 22% following Brazil which ranks first with 32% (Cheng, 2011). There are three main RE ore types in China with about 80% mixed ores in Bayan Obo, 10% bastnaesite ores in SiChuan and ShanDong province and 2.9% ion adsorption ores in Southern China. Bayan Obo mixed RE concentrate consists of bastnaesite and monazite. The concentrate contains CeO2/_REO of 50% and there are 7–8% F, 4-6% P and 0.2–0.3% Th."

Jan 1, 2016

By L. Chunpongtong

ABSTRACT The mining limit in oil sands is regulated by the ratio of total mining volume (ore, interburden, and overburden) one has to mine per volume of bitumen in place (TV/BIP). This paper presents a mathematical solution for creating the most economical pit outline where the TV/BIP ratio upper limit is 12, by combining mining economic theory and the Lerchs-Grossmann (LG) algorithm.

Jan 1, 2014

By L. Chunpongtong

The mining limit in oil sands is regulated by the ratio of total mining volume (ore, interburden, and overburden) one has to mine per volume of bitumen in place (TV/BIP). This paper presents a mathematical solution for creating the most economical pit outline where the TV/BIP ratio upper limit is 12, by combining mining economic theory and the Lerchs-Grossmann (LG) algorithm.

Jan 1, 2014

By C. A. Anderson, C. A. Young, H-H. Huang, L. G. Twidwell

An equilibrium calculational computer program (STABCAL) can be used for titration simulation. The program can handle various forms of titrants: solid, aqueous, gaseous or another solution, and various type of reactions: reductive, oxidative and adsorption. Background chemistry, mathematical considerations, and program development will be illustrated. Also, simple titration applications such as how to determine the acidity of aqueous solutions and alkaline sulfide leaching of gold are presented. Processing of an acid mine water from the Berkeley Pit in Butte, Montana has been used for illustration purposes. The treatment studies included: cementation, sulfidization, and neutralization. The calculational results for the neutralization treatment using various alkaline reagents are compared to actual experimental data and potentially appropriate processes are discussed. Computational

Jan 1, 2005

By I. B. Lambert

The guide has been developed by officials from resources and environment agencies in the Australian Government and the South Australian and Northern Territory Governments. It elaborates on the Australian Government?s policy that new uranium mines are to be approved subject to world best practice environmental and safety standards. The guide outlines the best practice principles and approaches that apply generally to mining in Australia, before giving more detailed consideration to best practice environmental protection and regulation for ISR mining.

Aug 1, 2010

By B P. Scott

Podsol soil horizons developed on Pleistocene glacial sediments overlying the Coronation Mine orebody were analyzed for copper and zinc spectro-photometrically, using biquinoline-isoamyl alcohol and dithizone carbon tetrachloride reagents. Copper and zinc are concentrated in the A. and C horizons, whereas the A1, A2 and B horizons are leached. Of economic significance is the fact that the C horizon contains a copper anomaly, in excess of 100 times back-ground, directly over the orebody. Due to the erratic distribution of high copper concentrations in the Ao horizon with respect to the orebody, that horizon is not considered as a reliable prospecting datum. U NDER certain conditions, metallic ore deposits are accompanied by primary halos of trace elements in unweathered rock surrounding the orebodies or by secondary halos in weathered rock, alluvium, soil, or vegetation above or near the mineralized zones. Where such halos occur, chemical analysis, as applied to the detection of trace elements, is a valuable prospecting aid, permitting the detection of mineralization of possible economic value.

Jan 1, 1965

By M. M. C Jiménez, D. C. Buzzi, D. C. R. Espinosa, J. A. S Ténorio, G. F. R Oliveira

In this work the extractive and selective capacities of solvent extraction synergistic systems to recover nickel and cobalt were evaluated. The liquor used was from the high pressure acid leaching process (HPAL). Initially the industrial liquor, processed from lateritic ores, was analyzed to identify the concentrations of the metals. Experiments of synergistic solvent extraction were performed later. The extraction liquid-liquid was carried out with a mixture of Cyanex 272 (CY) and Ionquest 290 (IQ) extractants. The process was executed with the temperature of 65 ºC, pH of 5.2 and the ratio aqueousorganic 2:1. Systems of 80% kerosene and CY 20%, CY 16% - IQ 4%, CY 12% - IQ 8%, CY 8% - IQ 16%, CY 4% - IQ 16%, IQ 20% were studied during 20 minutes. The results of this paper showed that the mixture of these two extractants doesn’t improve significantly the recovery of nickel and cobalt from liquor.

Jan 1, 2014

By S. C. Radopoulou

Pavement condition assessment is an indispensable constituent in maintaining roadway infrastructure. Current practices for pavement condition assessment are labor intensive which introduce subjectivity in pavement rating and are time consuming. Automated methods rely on full 3D reconstruction of the pavement surface which introduces high equipment and computation costs. This paper presents a methodology for detection of patch type distresses in asphalt pavement images. This method uses filtering and histogram equalization for clearing and enhancing the image accordingly. It continues by applying the morphological process of closing, along with some rules based on the characteristics of a patch when captured in an image, to finally detect the area it occupies. Criteria for area, length, and width of a patch as seen in an image are taken into account to decide whether a probable patch is actually a patch. The method has been implemented in C#. The preliminary experiments demonstrate it produces promising recognition results

Aug 1, 2013