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By Gae On Kim, Ki Baik Kim, Suk Hoon Kang, Tae Kyu Kim, Sanghoon Noh

"Advanced radiation resistant oxide dispersion strengthened steel (ARROS) is being developed as a fuel cladding tube material for future nuclear reactor system applications. The research activities consist of advanced radiation resistant ODS steel development and fabrication technology development of ODS steel structural components. One candidate material with a chemical composition of (in wt%) Fe-10Cr-1Mo-0.5Mn-0.1V-0.25Ti-0.35Y2O3and was selected as representative materials, and this material was named as the advanced radiation resistant ODS steel (ARROSTM).On the basis of this ODS steel composition, an optimized fabrication process of structural components such as plates, sheets and tubes has been established through various process conditions in mechanical alloying, hot/cold working, and heat treatment processes. These R&D activities are expected to contribute to the realization of ODS materials in the future.INTRODUCTIONA sodium-cooled fast reactor (SFR) is being developed at the Korea Atomic Energy Research Institute (KAERI) with a view to economics, safety, reliability, and sustainability. The prototype Gen-IV SFR with a capacity of 150 MWe is under design, and this prototype reactor is scheduled to operate from 2028. For a commercial SFR system application, it is necessary to develop an advanced structural material having both high creep strength and irradiation resistance at high temperatures (Jeong, 2014). Oxide dispersion strengthened (ODS)steel is one of the most promising structural materials because of its excellent creep and irradiation resistance on the basis of uniformly distributed nano-oxide particles with a high density, which is extremely stable at high temperatures under a neutron irradiation environment for a prolonged operating period(Kim, 2016). As the first step, several batches of ODS steel were designed and the candidate samples with a 2 kg scale each were fabricated by mechanical alloying, hot isostatic pressing and hot rolling processes. The mechanical properties of these samples were evaluated. Up to now, two candidate materials with chemical compositions of (in wt%) Fe-10Cr-1Mo-0.5Mn-0.1V-0.25Ti-0.35Y2O3 was selected as representative materials, and these materials were named as the advanced radiation resistant ODS steel (ARROSTM).The next step was to optimize the fabrication process of the ARROS compositions for in-core structural components such as the fuel cladding tubes of a SFR. An optimized fabrication process of fuel cladding tube with a composition of ARROS has been established through various process conditions in mechanical alloying, hot consolidation, hot/cold working and heat treatment processes. Joining technologies of the ODS steel tubes is being developed using solid-state welding such as magnetic pulse welding, friction stir welding and diffusion boding. It is expected that the development of ARROS will contribute to the realization of a commercial SFR with high economics and sufficient safety in the future. In this paper, the study of fabrication process of ARROS structural components is introduced."

Jan 1, 2017

By Pura Alfonso, Sarbast Hamid, Hernan Anticoi, Eduard Guasch, Josep Oliva

"Av. Bases de Manresa 61-63, Manresa (08242) Barcelona, SpainTantalum is a strategic metal and an improvement of the mineral processing is an important issue. The main objective of this work is to optimize the grinding technologies for tantalum ores with high pressure grinding rolls. The selected ore for this study was an altered leucogranite from the Penouta Open Pit Mine (NW Spain). In the present work mono-size experiments have been carried out using grinding rolls with controlled pressure. The particle size distribution has been monitored in the input and output of the high pressure grinding rolls for each experiment. The cylinder pressure that is transmitted to the particles has been determined. New population balance models are presented for high pressure grinding rolls with parameter adjust for tantalum ore. The obtained model uses the physical description of particles under the comminution action of the grinding rolls. The obtained results are in agreement with other models and the errors in the adjustment are low. The selection function proposed for this model describes adequately the breakage probability of the particles inside the high pressure grinding rolls. The presented model can be a good alternative for simulating a high pressure grinding roll process. INTRODUCTIONTechnology for grinding have been improved for many years, introducing new variables and parameters involving energy consumption, mechanical stress analysis of the compression particles or pressure application for optimizing the comminution (Morrell et al, 1997). High pressure grinding rolls is a modern technology that is proven to reduce the operating costs in full scale plants when compared with other milling technologies. Its benefits on energy saving and simplicity in the process have been studied and applied, first in the cement clinker industry (Abouzeid & Fuerstenau, 2009) and after in mining activities, especially in metallic ore deposits (Austin et al, 1991; Guevara & Menacho, 1992; Morrel et al, 1997; Torres & Casali 2009; Numbi & Xia, 2015). Many author structures of the High Pressure Grinding Rolls modelling in three main branches; (a) throughput modelling, (b) Power and energy model and (c) particle size distribution modelling (Austin et al, 1991; Guevara & Menacho, 1992; Austin & Trubelja, 1994; Morrel et al, 1997; Torres & Casali, 2009)."

Jan 1, 2016

By Unknown

Diesel locomotives for underground haulage have been used in coal mines in Continental Europe for twenty-five years or more. In Great Britain, it was not until 1935 that permission was granted to use them in gassy coal mines, but since that time they have been employed in increasing numbers both in gassy and non-gassy coal mines and in metal mines. Their use underground in coal mines in the United States is still prohibited and the same was the case in Canada until 1946, when permission was granted to operate a Diesel underground in the Adanac mine of West Canadian Collieries, Limited, at Bellevue, Alberta. The locomotive used here is a 50 h.p. Hunslet Mark II. More recently, a 100 h.p. Diesel was placed in operation for underground haulage at No. 18 Colliery of the Dominion Steel and Coal Corporation, in the Sydney coalfield, N. S. Thus, on this continent, Canada has been a pioneer in the use of these locomotives underground in coal mines and there is no doubt that more and more of them will be employed as time goes on. We feel, therefore, that the following notes concerning their design and performance, which we have received from the High Commissioner for the United Kingdom, will be of interest to our members.

Jan 1, 1949

By W. Blum

Progress made in improving the creep resistance of Mg alloys is reviewed with the emphasis on microstructural interpretation. Experimental results on the increase of creep strain with time at constant stress a measured for limited times and strains are displayed in a transparent form as creep rate-strain diagrams from which the minimum creep rate stress is safely derived. In addition, data on the thermal stress component a derived from high-precision a-reduction tests are reported. Within a simple statistical dislocation model these data allow one to quantify the relation between dislocation velocity v and a . In combination with structure evolution laws this relation serves as a basis for modeling the creep rate. New alloys have distinctly higher creep resistance than AZ91 where precipitation hardening plays a minor role. This is due to hardening by intermetallic phases which may form a continuous skeleton along the grain boundaries (e.g. Ca-alloyed AZ91) and/or submicron-sized precipitates within the grains (MRI230D, Mg-Zn-Ca alloys).

Jan 1, 2006

By S. Kashani-Nejad

The kinetics of the thermal decomposition of samples of Mg2(OH)3Cl.2H2O that were obtained by a novel leaching technique applied to a commercial magnesium electrolysis feed were investigated under ambient atmosphere. Thermogravimetric (TG) Analysis showed that decomposition of Mg2(OH)3Cl.2H2O exhibited a single intermediate stage wherein crystalline water was lost at roughly 108 °C. Conversion of the resulting Mg2(OH)3Cl to MgO, HCl and 1120 occurred at temperatures above 398 °C. Thermal decomposition of anhydrous Mg2(OH)3Cl was seen to be consist of two stages. Both stages exhibit first order kinetics with respect to the weight percent of Mg2(OH)3Cl remaining in the sample. However, the rates of decomposition in the two stages were significantly different. Detailed analysis of the kinetic data suggested that the rate of decomposition of Mg2(OH)3C1 was controlled by the rate of removal of the gases released. The change in decomposition rate during the course of the experiments was explained by HCI being released in stage 1 and followed by release of H2O in stage 2.

Jan 1, 2004

By Les Philips

National Institute for Safety and Health?s (NIOSH, USA) Office of Mine Safety and Mine Safety and Health (OMSHR) has definitions for: -Proximity Detection as detection of personnel, vehicles and other objects near a machine using some type of sensor technology -Proximity Warning (aka Collision Warning) as detection of personnel, vehicles and other objects near a machine resulting in alarms that ?Warn the operator only ?Warn the operator and nearby personnel (two-way) -Collision Avoidance as the processing of sensor information resulting in control signals or actions that alter machine status/movement to avoid a collision by ?Computer control ?Human control

May 1, 2013

By Apoorva Bajaj

Iron ore mines of Steel Authority of India Limited (SAIL) have to comply with strict chemical composition norms laid down for iron ore lumps supplied to its steel plants. This requires a careful planning of the overall ore excavation operation. In general terms, the problem can be stated as: Given the chemical composition of ore for all excavation sites, excavation capacity of each shovel, distance of each excavation site from the crushing plant and the number of dumpers available for transport of the ore, find out the percentage of ore to be excavated from each excavation site such that the production rate is maximized and the chemical composition norm is satisfied to the best possible extent. This paper presents an approach to solve this problem using Branch and Bound method. The specification for r.o.m. quality has been modified by incorporating a new parameter, ?Al2O3 / SiO2? ratio, which has a significant effect on the performance of iron blast furnace.

Oct 1, 2009

By Pim van Geffen, Dave Lawie, James Cleverley

A growing problem facing geoscientists, metallurgists and process engineers is the lack of knowledge transfer between the exploration and production teams. This siloing is generally unintentional, as a typical project may change ownership several times over several decades before it reaches the feasibility and operation stages. Many exploration projects generate vast amounts of high-quality, quantitative data with great spatial resolution, but unfortunately these data are often ignored in subsequent deposit modelling. Instead, deposit models tend to rely on subjective, non-standardized, qualitative classification of geological materials (e.g. rock type, mineral abundance) and processes (e.g. alteration style and intensity), obtained through visual logging of drill core. When projects advance to feasibility studies, the required quantitative data are obtained through expensive metallurgical test work and detailed quantitative mineralogical analysis, such as QEMScan or qXRD. These detailed tests are generally only performed on a small number of large composite samples and the results are extrapolated throughout the deposit, inherently underrepresenting their true variability. Geochemical data obtained during all stages of the project provide comprehensive data coverage at much greater detail and spatial resolution, which allows for the estimation of key metallurgical performance parameters that are required for accurate deposit modelling and domaining.

Jan 1, 2015

By J. A. Reid

THE views and observations expressed herein on this old but constantly recurring question are our own, no effort having been made to align them with standard texts. Therefore, while they may find general acceptance amongst fellow engineers, they must stand as personal opinions and as such are open to debate and discussion. In order properly to consider the subject, it should first be 'set in proper perspective. Why are Prospects Examined? Prospects are examined to determine whether they may contain economic concentrations of metals or minerals, the legitimate mining business being run, pretty largely, to make money. Next to food and clothing, modern civilization is based on metals, with which are included in this discussion minerals, oils, and fuels. A constant and increasing demand for the common metals requires the location of replacements for depleted orebodies, while the use and appreciation of new metals brings increasing demand for them. Aluminium is a good example of a metal which has, within recent years, made great progress. Today, we are becoming increasingly aware of magnesium, chromium, tungsten, thallium, and other lesser known, metals.

Jan 1, 1945

By Yan Jie

The oxygen-enriched bottom-blowing continuous converting process for copper matte was recently developed by the China-ENFI Engineering Corporation. The first commercial plant based on this technology was successfully commissioned at the Yuguang smelter in China in March 2014. The present paper describes this new continuous converting process and compares technical characteristics with other continuous converting processes including: Kennecott-Outokumpu flash converting, the Mitsubishi Process, the Noranda Converter and TSL continuous converting. The bottom-blowing oxygenated continuous converter with competitive capex and opex costs is seen as an attractive alternative to the Peirce-Smith converter.

Jan 1, 2014

By Tao Cheng

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

Aug 1, 2013

By C. H. Bucknam

Net carbonate value (NCV) characterization methods for acid generation potential measurement originated from studies on the Carlin Trend during the 1990's and have been subsequently standardized through cooperation of the Acid Drainage Technology Initiative Metal Mining Sector and the American Society of Testing and Materials International. The paper describes the evolution and standardization of the NCV methods, the importance of mineralogy in interpreting the results and application of the methods to implementation of the Global Acid Rock Drainage (GARD) Guide.

Jan 1, 2011

By W. Petruk, D. R. Morris

"The lead concentrate produced from the volcanogenic base metal ore of Brunswick Mining and Smelting in New Brunswick contains major to trace amounts of iron, zinc, cadmium, arsenic, antimony, copper, silver, selenium, tellurium, bismuth, sulphur, tin, indium, mercury and manganese as impurities. When the concentrate is sintered some of these impurities enter a variety of oxide phases, whereas others precipitate as metals. In the lead blast furnace the oxide phases decompose and the impurities recombine 10 form new phases, most are eventually discharged to the slag. The metals of the sinter remain as metals in the lead blast furnace where even more are produced, and are discharged largely with the lead bullion,IntroductionMany lead concentrates are produced from volcanogenic base metal ores . Such ores contain a wide variety of trace minerals and trace elements , therefore, concentrate s obtained from them will contain the trace elements as impurities . The impurities in the lead concentrate from one such ore, the Brunswick No. 12 deposit of Brunswick Mining and Smelting Corporation (BM S) in the Bathurst area in New Brunswick , were studied as pan of a larger investigation that was conducted to determine the extent of chemical reactions of the sinter within the lead blast furnace(1,2) The lead concentrate was investigated to identify the host mineral s for the impurities, the lead sinter was studied to identify the host phases, and frozen products from different depths within the BMS blast furnace at Belledune, New Brunswick were studied to determine the behaviour of the impurities.T he investigation was performed by pre pa ring polished sections o f the samples and studying them with a reflecting microscope, a scanning electron microscope (SE M) equipped with a Kevex energy dispersive X-ra y analysis system, a microprobe, and a Quantimet 720 image analyzer. The samples were also analyzed by X-ray diffractometer, and individual grains were analyzed by the Debye-Scherrer X-ray powder film method."

Jan 1, 1985

By Zoltan Hajnal

Magnetic studies have been carried out on 88 surface and 157 underground samples from the Coronation Mine area of northern Saskatchewan. The intensity of the surface samples was compared to trace element determinations from the same locality. A good correlation was found between the titaniferous constituent of the rocks and the intensity of magnetization. From the direction of the remanent magnetism, two virtual geomagnetic poles were determined -latitude 12° 54' North, longitude 158" 17' West; and latitude 23" 42' North, longitude 163° 45' West. The sulphide ore specimens showed anisotropic susceptibility characteristics. A relationship was found between the measured maximum susceptibility values of the ore specimens and the direction of the tectonic forces which are considered to have formed the structure at the Coronation mine. Introduction T HIS paper summarizes the results of a study of the magnetic properties of samples from well-known Precambrian formations. The observed data give information for an interpretation of the magnetic field conditions in Precambrian times. The high magnetic intensity values indicate the importance of the study

Jan 1, 1965

By Y. Rama Murthy, Amit Ranjan, Pankaj Satija, Sunil K. Tripathy

"Chromite ore is one of the essential raw materials for ferroalloy and steel industry. Boula-Nuasahi belt of Sukinda region, Odisha, is the only resource of chrome ore in India. The Indian deposits are typically characterized as ferruginous and siliceous type ores. Chrome ore is generally mined by open cast mechanized mining method in these areas. The run-off-mine (ROM) ore from the various mines is sent to beneficiation plant via stack yard for further up gradation. The chrome ore beneficiation plant (COB) has two major circuits: comminution (feed preparation) circuit and beneficiation circuit. In the comminution circuit, the ore is reduced to <1 mm size ( for complete liberation of chromite) from -220 mm size in stage wise crushing (primary and secondary crusher) followed by screening and single stage grinding in a ball mill. Fraction having size <1 mm is further upgraded in the beneficiation circuit to produce three different concentrates having specific chemical composition and Cr: Fe ratio. The beneficiation plant is a complex circuit comprising of combination of unit operations (spiral concentrator, Floatex density separator, hydrocyclone, wet shaking tables). In the recent years the overall performance efficiency (grade and recovery) of the beneficiation circuit got affected with numerous changes in the run-off-mine ore quality (physical and chemical), mineralogical composition, etc.In this article, attempts made for improving the performance of chrome ore beneficiation circuit is discussed. The approach adopted and practical problems encountered while the process were also highlighted. The results of the trials has shown an improvement in the performance of the cyclone (d50 : 56 µm – 40 µm) and chromite losses into tailing to <12%.INTRODUCTIONChromite has a wide range of application, from refractories to metallurgical industries, and from chemical to non-ferrous alloy industries. Chromium ore (Fe2+, Mg) [Cr, Al, Fe3+]2O4) occurs exclusively in rocks formed by the intrusion and solidification of molten lava or magma which is very rich in the heavy, iron containing minerals such as pyroxene and olivine. With the richness of silica and iron, the chrome ores are broadly classified as siliceous type and ferruginous type. Pure chromite with composition FeCr2O4 is rare because magnesium usually substitutes for ferrous ion and aluminum and ferrous ion substitutes for chromium. Generally the associated gangue minerals are talc, quartz, hematite, goethite, limonite, gabro, serpentine, anorthosite, dunite, pyroxinite, etc. Around 96% of the chromite ore production is consumed for metallurgical applications of which 94% is converted into different grades of ferrochrome i.e., high carbon ferrochrome and charge chrome as shown in Figure 1. Stainless steel being the leading consumer of ferrochrome, any change in the dynamics of the stainless steel industry impacts overall chrome ore demands significantly."

Jan 1, 2016

By A. Liem, R. L. Johnson, C. Sturgess, E. Kuzub

New challenges in mineral processing arise as high-grade ores become less available and the mining industry is forced to exploit lower grade ores. One of the challenges in beneficiating lower grade ores is the liberation of mineral particles while maintaining control over material management. Lower grade ores need fine grinding to free valuable minerals, but finely divided particles can cause severe problems, such as dustiness and flowability, in subsequent stages of material management. There are at least two approaches that can be taken to resolve this dilemma, both of which relate to particle size enlargement. First, the application of a dust suppressant can be used to control that aspect of material management. The optimal choice of dust suppressant agent depends on effectiveness and cost, both of which can be strongly influenced by the selection of application method. Second, agglomeration combining small particles into larger units-can reduce dust and improve the flow characteristics of the material at the same time. There are several mechanisms that can be employed to agglomerate mineral materials. Although agglomeration adds a new processing step, it is often cost effective. This paper describes these two approaches and their respective challenges, as they relate to a mined ore. We report on modified or newly developed procedures for characterizing mineral ores with respect to material management. On the same material, we use agglomeration processing to capture fines within larger particles and show how dustiness and other aspects of material handling are affected. We conclude by discussing their specific application in accordance with the mineral properties and processing needs.

Jan 1, 2004

By G. D. Garland

The influence of natural electric currents, induced in the earth by changes in the earth's magnetic field, on the electric logging of boreholes has not always been recognized. Measurements made with fixed electrodes of changes in the vertical potential gradient in a hole near Calmar, Alberta, have indicated the effect of earth currents related to magnetic disturbances. It is found that appreciable errors in self-potential logging could arise during periods of magnetic storms, but the precise pat-tern of disturbance in any area seems to depend on the local structural conditions. As the amplitude of the natural earth currents increases toward the auroral zone, it is suggested that periods of magnetic disturbance be avoided, if possible, when electric logs are taken in the northern part of the western sedimentary basin. NATURAL electrical currents flow continuously near the surface of the earth, apparently as a result of electromagnetic induction

Jan 1, 1962

By W. Keith Buck

Introduction During World War II years, the magnetometer was used by various field parties of the Geological Survey of Canada, specifically in the search for chromite, a strategic war mineral. Throughout the summer of 1944, Professor J. W. Ambrose used the instrument experimentally on eight separate projects (1). Since then, several members of the Survey have come to consider its use to be of valuable assistance in the season&apos;s mapping. Dr. C. H. Stockwell, in particular, regards use of the magnetometer as a necessary part of detailed geological survey work. Throughout the field season of 1949, the magnetometer was used by Dr. Stockwell?s party as an aid to mapping in detail, to the scale one thousand feet to the inch, the south-west quarter of Dasserat township, Temiskaming county, Quebec. The principal geophysical project that was undertaken was the location of the Horne Creek fault and the Diabase fault in the area approximately midway between Arntfield and Kearns, on the Quebec side of the Interprovincial border. The location of these faults on either side of this central area was known. The Horne Creek fault is a subsidiary fault to the Cadillac &apos;break&apos; which extends ?westward from Val d&apos;Or through Cadillac to beyond Larder Lake. It lies to the north of that major fault zone and has a general southwesterly trend.

Jan 1, 1951

By P. C. Benedict, J. A. Titcomb

"The following description of the geology of the Northern Empire mine is recorded by the senior author, but is based on the observations and complementary mapping of both authors.The Northern Empire mine is a mile east of Beardmore, and 100 miles northeast of Port Arthur, Thunder Bay district, Ontario.Production started in March, 1934, and terminated in September, 1941. The total number of tons milled was 425,866, from which 153,103 oz. gold was recovered. The lowest level from which ore was mined was the 1,900- foot, but considerable drifting was performed on the 2,075-foot and 800 feet on the 2,415-foot, the deepest level,The vein strikes about N.72°E. and has an average dip of80°S. In stoped sections the quartz averaged about 2 feet wide. On the 1,725-foot level it was drifted on continuously for more than 7,000 feet. In the mine as a whole, practically no commercial ore was found beyond points 1,400 feet west and 1,800 feet east of the shaft. Conspicuous wall-rock alteration extended throughout this section, but not much beyond these limits. There was some splitting of the vein and widening of the alteration halo on the lower levels. The average general colour of the quartz changes with depth .The vein is in 'Keewatin' lava flows, to which it is almost conformable. It lies only a short distance south from the 'Timiskaming-Keewatin' contact ( Fig. 2). This contact is marked by a black graphitic fault. So far as is known the fault is parallel, or nearly parallel, with the flows in strike, but dips at 72°S., which is 5° flatter than the average dip of the overturned flows. A post-vein, almost flat sheet of diabase about 550 feet thick cuts outthe vein from about the 650- to the 1,200-foot level ( Figs . 1 and 3). If it was intruded along a fault, the fault had only minor displacement. A strong alteration halo extends to 200 feet above and below the diabase. The vein was conspicuous but in large part it was below ore grade for 100 feet or more above and below the diabase.-"

Jan 1, 1954

By T. G. Phillips

"This paper gives an inside look at a bulk terminal and describes the preparations that must be made by a company in developing such a terminal and its position in today's traffic pattern. The following headings cover the subject material: (a) Traffic pressures, their detection and measurement, (b) position in the traffic flow -selection of site, (c) transportation connections -present and possible future routes, (d) engineering studies and costs, (e) contracts, the basic material for insured traffic, (f) financing, (g) budgetary control, (h) development of new techniques, (i) growth into new cargoes or cargo-handling methods and (j) consolidation."

Jan 1, 1968