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By Junto Nishiwaki, Shinji Kumai

"Mechanical and physical properties of the impact welded dissimilar metal joints are controlled by joint interface morphology. An intermediate layer (IML) is often formed at the joint interface and this deteriorates the interface quality in some metal combinations. Numerical and experimental studies were performed in order to examine the formation mechanism of the wavy interface and intermediate layer for explosive welded Al/Cu dissimilar metal joints. The impact welding process consists of (1) high-speed oblique collision of metal plates, (2) metal jet emission and large deformation and temperature increase at collision point and (3) rapid cooling at the joint interface. Euler-Lagrange coupling method, smooth particle hydrodynamic (SPH) method and modified laplacianFoam (LF) method were linked together to simulate a series of processes from (1) to (3), and the final interface morphology including the formation of IML was reproduced. The wavy morphology (wave-height, wavelength) and the position and composition of IML formed at the joint interface of Al/Cu joints were quantitatively in good agreement with those reproduced by numerical analysis. Our simulation results are useful for the control of the interface morphology, reduction of the amount of IML, and improvement of the mechanical properties of the impact welded dissimilar metal joints.INTRODUCTIONImpact welding is a kind of solid state joining method providing extremely high joint strength for both similar-and dissimilar metal combinations. Explosive welding and magnetic pulse welding are representative methods to achieve the impact welding. By a high-speed oblique collision between two metal plates, a metal jet is emitted from the collision point. The metal jet can remove any oxide films and contaminations on the plates and produce an active refreshed surface. Consequently, good metallurgical bonding can be achieved even for dissimilar metals (Crossland, 1982). Solid metals deform like fluids under the high pressure condition at the collision point and characteristic wavy interface is formed. In addition to the wavy interface, an intermediate layer (IML) is often formed at the joint interface in some metal combinations. Elimination or reduction of the amount of IML at the joint interface is desired since the excessive IML formation along the joint interface causes a large reduction in physical and mechanical properties. Formation of IML is considered to result from characteristic thermal history at the joint interface including partial melting due to the local temperature increase and successive rapid cooling behavior at the joint interface. In order to control the IML formation at the joint interface, it is necessary to reveal both heating and cooling processes at the joint interface. However, it is impossible to observe the phenomenon occurring at the joint interface and also difficult to investigate the temperature change at the joint interface directly during the impact welding. Therefore, simulation or numerical analysis is indispensable to overcome this problem. In the present study, the explosive welded Al/Cu joint, which is prone to form IML at the joint interface, was selected for the research. By using a newly developed numerical analysis method, not only the formation process of wavy interface, but also the local temperature increase and successive temperature decrease at the joint interface were reproduced. The formation process of IML was investigated by using both numerical analytic and experimental results."

Jan 1, 2018

By W. N. Hamilton

Industrial minerals are plentiful in Alberta. Although exi ting in variety and in quantity, they constitute a minor segment of the province's mineral industry, which is based on oil and gas. In 1983 Alberta led all the other provinces in value of mineral production with a total of $22,2 18 million, 62 per cent of the total for Canada. Of Alberta's total, $22 million or about 3 per cent came from the indu trial minerals. Nearly two-third of this production is accounted for by sulphur, which is actually a by-product of the oil and ga industry. Alberta ranked third among the province in industrial minerals production for 1983, with about 20 per cent of the national total.

Jan 1, 1984

By Alexander Smith

"The three principal known mineral deposits of the Taku River area lie in the Tulsequah synclinorium. The axis of this north-south trending structure is along Tulsequah River valley; about 6 miles east of the eastern contact of the Coast Range batholith.The one proven mine of the area, the Polaris-Taku, is on the west side of the valley. It is a gold property, the gold occurring in fine needles of arsenopyrite disseminated in carbonatized volcanics. The mine was originally called the Whitewater, and the adjacent area the Whitewater gold belt. During the years 1937 to 1942 gold having a value of $3,284,000 was produced from 313,500 tons of ore milled."

Jan 1, 1954

By J. Mullins

Coal was first banked by the Dominion Coal Company, Limited, in 1898, near No. 2 Colliery, the same site as is presently used for that purpose. Though today there are banks at Glace Bay, Sydney, and Sydney Mines, these notes, except when otherwise desirable, will be confined to describing the practice as developed at the No. 2 Banking Station, Glace Bay, as being typical of methods obtaining at all sites. Storing The manner in which the coal was piled is illustrated diagrammatically in the accompanying sketch. A train of coal was brought on the main trestle, which extended the full length of the banking ground at a height of 22 to 39 feet above the natural surface, and dumped into bins which were integral with the trestle work. Chutes from these bins permitted the coal to be fed into 3-ton cars, which were horse drawn laterally on narrow gauge tracks laid about 10 ft. centres, to a maximum distance of 400ft. from the trestle. These cars were end-dump and as the pile extended laterally the narrow gauge tracks were lengthened by shorter or longer filling pieces, so that their ends were always kept at the brow of the bank. Much coal, however, had to be dumped directly on the tracks and hand trimmed to fill the valleys, and level off, between the tracks.

Jan 1, 1931

By W. Holdsworth

The flotation mill of Dentonia Mines, Limited, at Greenwood, B.C., went into operation on April 20th, 1934, and by October 11th a total of 15,000 tons of ore had been treated. It is intended in this paper to describe briefly the operation and to give some of the operating data which have been gathered. The metallic minerals in the Dentonia ore are pyrite, chalcopyrite, galena, and, occasionally, native gold, and the gangue includes chloritic material, vein quartz, and calcite. Pyrite makes up about 90 per cent of the metallic content of the ore, in which it is disseminated as irregular grains and well-formed cubes. An average analysis of the ore is: gold, 0.27 oz. per ton; silver, 1.73 oz. per ton; copper, 0.12 per cent; lead, 0.31 per cent; and zinc, trace. From the mine ore-bin, situated near the portal of the tunnel at the mine, the ore is hauled by motor truck to the mill, a distance of three-quarters of a mile, and there dumped into the receiving bin, which has a capacity of fifty tons. The hauling is done during one eight-hour shift, commencing at 7 a.m. The maximum size of the ore fed to the mill-bin is ten inches. Lumps larger than this are broken by sledge hammer to pass through grizzly bars, spaced ten inches apart, installed above the bin. The ore is drawn from the bin by a 30-inch, 6-ply conveyor belt, 18 feet 6 inches long. In the near future, when the cross-cut tunnel is completed, the ore will be trammed to the receiving bin. This will effect a considerable saving in cost. At the same time, the bin will be set back several feet, so that the length of the conveyor belt may be doubled. This will make efficient ore-sorting possible, and so ensure a minimum of waste rock in the mill feed.

Jan 1, 1935

By A. I. A. Salama, M. W. Mikhail

"A comprehensive software package has been developed at the Western Research Centre to meet many of the coal preparation requirements in the Canadian coal industry. This package performs three main functions: (1) data handling and manipulation; (2) data analysis, including the generation of washability data, performance evaluation and prediction, density and size modelling, evaluation of density and size partition characteristics, and attrition curves; and (3) graphics output.The software described in this paper is potentially a valuable tool for coal preparation plant engineers and operators for evaluating process performance and adjusting plant density separator cutpoints. Moreover, the analytical laboratory technician could find this package very useful in manipulating and presenting laboratory results."

Jan 1, 1997

By Ming’an Wei, Qifu Duan, Chengtie Wang, Jianmin Wu, Erdenet Mining Corporation, Lusheng Zhou, Wenjian Wu

"The development and industrial applications of magnetic liners have been around for decades. A Swedish company SKEGA first introduced the rubber magnetic liner, and then followed by the Chinese metal magnetic liners. Traditionally, both liners were used in secondary and regrind ball mills, especially for ores containing magnetic materials. Mostly steel balls or equivalent forged balls, usually below 60 mm in diameter, were used as grinding media. With the development of mineral resources over the years, SAG mills and larger ball mills have become the dominating components for comminution circuit design globally. Due to the larger ball mills and thus larger grinding balls (up to 80 mm) especially in non-ferrous metal industry, the application of magnetic liners has been very limited. Based on the new development of materials, the HMR Group Limited has been exploring new designs of magnetic liners which led to the invention of the Nano Steel Magnetic Liner (NSML). Recently, NSML had a successful application in a 5.5m x 6.5m ball mill with 80 mm balls at the Erdenet Copper Mine in Mongolia. Although the first set of liner had a service life of 12 months, the design of the second set was modified and improved to accommodate the operating conditions, which is expected to reach least 24 months service life. The original manganese steel liner only had about 8 months liner life.1. IntroductionMineral processing is an essential operation for the development and utilization of mineral resources. The effective concentration of various useful minerals depends on sufficient liberation of the mineral particles in the ore. The crushing and grinding process such as ball milling are the most common way to achieve proper liberation size. Mill liner is an eternal topic for the operations, not only because it protects the equipment, but also affects the mill grinding efficiency and availability. In recent years, magnetic mill liners have been developed that can easily meet the production targets with numerous benefits, such as zero maintenance, reducing specific energy consumption and improving grinding efficiency."

Jan 1, 2016

By Y. X. Li, L. R. Xiao, S. Gong, S. S. He

Porous copper and porous copper based alloys with controllable pore structure have been manufactured successfully by sintering evaporation process. This process consisted of mixing copper or copper based alloys with NaCl powders, hot pressing and final high-temperature sintering to evaporate the filler material of NaCl powders. NaCl was eliminated completely during vacuum sintering, and strong metallurgical bonding in the walls was achieved. The pores’ structural parameter (pore size, shape, and direction) and porosity can be controlled effectively. These porous copper and porous copper based alloys with controllable pore structure have great potential in many fields. Including heat dissipating materials, heat absorbing materials, chemical catalyst carriers, electromagnetic shielding materials, filtering materials, damping materials, silencing materials, battery electrode materials. INTRODUCTION The development of porous materials began in the 1960s. The research of activated carbon with high specific surface area made porous materials enter the stage of material research (Belyakov et al., 2008; Ferey et al., 2008). With the rapid development of science and technology, porous materials play an important role in material research, and gradually become an indispensable part of the material research field (Wu et al., 2012). The research of porous materials has gradually extended to metal, ceramics, plastics and glass and other fields. It has been successfully applied in many fields, such as functional materials, industrial production, aviation, medical materials, biochemistry and electronics, which fully shows that porous materials have considerable development prospects. Porous silicon, plastic porous materials and glass porous materials are the most widely used in the field of non-metallic porous materials (Capelle et al., 2012). Compared with non-metallic porous materials, metal porous materials have developed rapidly in the late 1980s and become new materials with good mechanical properties and excellent physical properties. Porous metal materials have many advantages, such as large specific surface, small specific gravity, good silencing effect, high stiffness, high electromagnetic shielding performance, good shock absorption performance, etc (Li et al., 1999; Ferey et al., 2008). Among its many applications, metal porous materials can be used as both functional materials and structural materials. In some cases, metal porous materials have dual functions and structures. It is a multi-purpose engineering material with excellent performance. At present, porous copper, porous aluminium and porous nickel are the most concerned materials (Chen et al., 2002; Yang et al., 2017; Liu et al., 2018). The preparation methods of porous copper and copper-based alloys mainly include self-propagating high temperature synthesis (SHS), capsule-free hot isostatic pressing (CF-HIP), spark plasma sintering (SPS) (Kvanin et al., 2008; Takahashi et al., 2008; Zhang et al., 2014). However, these methods can not accurately control pore structure parameters (including pore size, shape, orientation, distribution, etc.). In porous materials, pore structure plays an important role in the overall performance of materials. In order to control pore structure parameters accurately and optimize material performance, it is necessary to explore and develop new preparation technology. In this paper, the sintering evaporation process (SEP) was introduced for the preparation of porous copper and copper-based alloys. The core process of the preparation method is hot pressing and evaporative desalination. Hot pressing can make the pore orientation consistent. Evaporative desalination can ensure the complete removal of NaCl in the form of vapor in a short time, thus eliminating the corrosion of residual NaCl on the matrix metal (Gong et al., 2011).

Jan 1, 2019

By D. L. Babbitt, Sniezek

"This paper deals with the varions methods for the rapid Joading of unit trains which are being: used by ore procossors to move their product to dock-s1de storage facilities or their ultimate customer. Some of the techniques that have been used include (1) volumetrie loading, both in motion and static, (2) batch weighing into moving cars and (3) batch weighing into cars that have been stopped. Particular emphasis shall be placed on the two systems now in use at the Adams Mine facility of Jones and Laughlin Steel Corporation and at Cliffs of Canada's Sherman Mine. Typical ""turnaround"" times, loading rates, types of cars, weighing accuracies, material handling concepts and maintenance considerations shall be discussed."

Jan 1, 1969

By L. Dufourm

This paper presents a review of plant layout considerations incorporated into recent designs of SAG/Ball mill circuits for two medium sized concentrators. The plant layouts presented and the design concepts discussed, relate to smaller SAG circuits, but can equally apply to larger milling circuits. Included are design concepts and ideas introduced by the various project teams, and the focus is on the primary factors of any layout design which are safety, constructability, operability, and capital cost.

Jan 1, 2012

By J. D. Jones

The geographic occurrence of economic mineral deposits presents a variety of problems in modern tailings disposal operations. This paper presents case histories in several sectors of the mineral industry as well as the several stages of operations planning required for new designs, system expansion, reactivation of abandoned systems and upgrading to present environmental standards.

Jan 1, 1978

By C. M. Trigg

"PEC uranium deposit, 100 km southwest of Coppermine, was discovered by diamond drilling in 1976 following ground and airborne geophysical surveys, geological mapping, geochemical surveys and boulder prospecting that were initiated as the result of the discovery of uraniferous sandstone outcrops in 1969 by geologists of Aquitaine Company of Canada Ltd.The deposit is within gently northeasterly dipping medium to coarse-grained Unit 11 quartzitic sandstone of Neohelikian Dismal Lakes Group. The deposit is from 10 m to 70 m above the base of the sandstone which, beneath the deposit, non-conformably overlies weathered and altered Aphebian granite of Great Bear Batholith or unconformably overlies rubble breccia, conglomerate and medium-grained Unit 8 sandstone of Paleohelikian Hornby Bay Group.A northeasterly trending, 500 m wide graben, bounded by the steeply dipping northeasterly striking Imperial and Aquitaine faults, contains the deposit which is 1.1 km long by up to 340 m wide. The deposit overlies a post-Hornby Bay Group, pre-Dismal Lakes Group topographic high. Uranium principally occurs as stratabound, often peneconcordant bands; a lesser amount of uranium is fracture controlled.Stratabound uranium exists in gently easterly dipping, subparallel bands ranging in thickness from 1.5 m to 6.0 m. Pitchblende, coffinite and sooty black uranium oxides occur as interstitial disseminations and grain coatings subparallel to bedding; they also replace pyrite and form narrow veinlets.Small amounts of torbernite, carnotite and cuprosklodowskite coat pitchblende and are disseminated within mineralized bands. Pyrite, marcasite, chalcopyrite, chalcocite, cove/lite, digenite, azurite, malachite, arsenopyrite, glaucodot, niccolite, bravoite (? ), goethite, hematite and magnetite as well as quartz, barite, calcite, biotite, chlorite and clay minerals exist within the mineralized bands. Uranium grades of 0.1 % to 0.3 % U3O8 over thicknesses of 1 m to 2 m are typical.A steeply dipping fracture zone near the Imperial fault contains sooty black uranium oxides, torbernite, carnotite and cuprosklowdowskite as well as sulphides, cobalt arsenides, quartz and carbonate. The zone may reach 70 m long; its true width is about 1.9 m. Uranium grades range up to 5.18% up, over0.9m.Pitchblende and coffinite from PEC deposit have been dated at 1.08 ± .10 Ga with possible remobilization at .45 Ga. The deposit contains an inferred 3,150 tonnes of U3O8."

Jan 1, 1986

In Canada and other countries, legislation dealing with accurate factual disclosure for mining projects is being expanded to include more metallurgical design information. Grinding characteristics, metallurgical recovery of contained metal and environmental hazards associated with tailings disposal will be part of the Canadian package. This paper will examine only that portion of the plant design standard practice that relates to grinding ? in SAG mills and ball mills that grind ore from as received crushed material to final ground product that is fed to downstream plant recovery processes. Since grinding plants represent a significant portion of the overall concentrator cost, accountability in grinding design should no longer be left to chance, opinion, or hidden proprietary information. This is the 21st century. It is reasonable to expect that a factual basis will be needed so that a Qualified Person (QP) reviewing the grinding mill design can understand it. That will also involve how many and what quality of samples are taken to define the characteristics of the deposit, the accuracy of the tests used to measure ore hardness and the method by which the dimensions and power of the mills are determined. If these criteria are not met, the QP may have no choice but to call attention to the lack of convincing information regarding the grinding mill design for the project. At the same time clients are expected to demand getting the correct design information at a cheaper price, results in a more timely way, and accurate design to the point where the risk of tonnage shortfalls are reduced or eliminated. Tables will be presented to show how this can be done to current standards using existing technologies. At the same time it is acknowledged that current standards are ill-defined and that to achieve consensus among those involved in SAG mill design work, it may require that a consortium funded project be set up to establish what tests and methods for grinding design are suitable to meet the new standards for metallurgical disclosure. By running parallel design methods on several major projects over a period of 5 years, the process of how to design grinding circuits will be better understood because the projects will start at the design stage, include procurement of the mills and will end with a benchmark test on the plant. Selecting the samples and the best schedule for doing test work on core samples submitted and mill design, will be discussed in this paper. The issue of completing the grinding design in time for early procurement decisions is on the critical path for most major projects. Discussions between mining engineers, geologists and process engineers are needed early in the development cycle, at the scoping study level (SS), preliminary engineering assessment (PEA), prefeasibility study (PFS), and at the feasibility study stage (FS), to ensure that proper planning for design sample selection is done. Using adequate sampling and testing methods in a timely way allows early procurement of the grinding mills and minimizes project risk.

Jan 1, 2012

By L. Yuan, J. H. Rowland, R. A. Thomas, D. Bahrami, G. P. Cole

"The past several decades have seen a steady increase in the use of atmospheric monitoring systems (AMS) in underground mines as sensor technology has advanced and costs for this technology have decreased. The AMS is a reliable tool for early mine fire warning by detecting gaseous products of combustion in underground mines. During a mine fire emergency, mine decision makers rely heavily on the prompt and accurate knowledge of the ventilation and fire situation in the mine, such as fire location, fire size, and the spread of smoke to make effective and efficient decisions on firefighting strategies and miner evacuation. Meanwhile, a prediction of the potential for fire development at a later time, such as whether the currently designated mine escapeways will be contaminated by smoke and toxic gases with the progress of the fire, is critical for effective decision-making to save lives that are in danger. The AMS monitoring data, including carbon monoxide (CO) concentration, airflow rate, smoke, etc., can provide information as to whether the smoke has reached the locations where AMS sensors are installed and if a mine-wide smoke spread has occurred. The National Institute for Occupational Safety and Health (NIOSH) has undertaken a task to integrate real-time AMS monitoring data with the mine fire simulation program, MFIRE, to simulate and predict the spread of smoke and toxic gas in a ventilation network based on the real-time AMS data. This paper reports the developed real-time method for characterizing the size and location of an underground mine fire and for predicting the spread of contaminants throughout the mine ventilation network using sensor data from the AMS.INTRODUCTIONNIOSH conducts research to develop workplace solutions to improve detection of and reduce the risk of hazardous conditions in underground mines. The advancement of senor technology and the increasing demand for real-time mine parameters monitoring have led to extended applications of atmospheric monitoring systems (AMS) in underground mines worldwide. In the United States, AMS is primarily used for early mine fire warning by detecting carbon monoxide (CO) in fire hazard areas, such as belt entries. Mine fires can grow rapidly, and time is the critical element. Prompt detection, timely and accurate warnings to those miners potentially affected, and a proficient response by underground miners can have a tremendous impact on the social and economic consequence of a small underground mine fire (Conti et al., 2005). The early detection of a mine fire could gain time for the first responders to put out the fire before it develops into a disaster. An AMS system with CO sensors has especially played an important role in the early detection of mine fires. The continuous monitoring of an underground mine atmosphere with an AMS could generate a large amount of data in a mine fire event. However, the current application of AMS is mainly limited to sending out an alarm when monitored CO concentration exceeds a certain level. An opportunity arises as to whether these data can be further used in fire emergency response. In order to make effective decisions on firefighting strategies, mine workers’ seeking refuges, evacuation and escape, and the timing on when to send rescuers, decision makers need accurate and timely knowledge of the ventilation and fire situation in the mine. Information about the fire intensity, where in the mine the smoke and toxic gases have spread, and whether designated mine escapeways have been compromised by smoke and toxic gases from the fire would greatly increase the effectiveness of these decisions. However, the monitored AMS data only provides atmospheric conditions in the vicinity of sensor locations. What is concluded from the monitored AMS data highly depends on the decision makers’ capability and experience. Predictive insight into fire growth and smoke transport would greatly help decision makers during a fire emergency."

Jan 1, 2019

By M. E. Holter

"Limestone-bearing strata are exposed in seven areas of Alberta, each situated adjacent to rail and road facilities. Six of these centers are located along the eastern edge of the Foothills and Front Ranges of the Rocky Mountains in western Alberta. The other is in northeastern Alberta, along the eastern margin of the Alberta Basin. High-grade limestones are present in Middle Cambrian, Upper Devonian and Mississippian strata. Middle Cambrian (Eldon Formation) limestones have been exploited only in the Exshaw area west of Calgary, where they formerly were used for lime production. Limestone beds of the Upper Devonian Palliser Formation are exploited at Exshaw and at Cadomin in west-central Alberta for the manufacture of cement. Reserves of high-grade limestone also are available in the Palliser Formation near Crowsnest Lake in southwestern Alberta and near BrUle, west of Edmonton. Upper Devonian limestones of the Waterways Formation are widespread in the Fort McMurray area of northeastern Alberta, but available data indicate they are of inferior quality to the limestone deposits of the Rocky Mountains regions. The Mississippian Livingstone Formation contains large reserves of high-grade limestone at several localities in the Rocky Mountains and Foothills. Commercial development of the unit is now underway at Crowsnest Lake and at Exshaw for lime production, and future exploitation of these beds is feasible at Blairmore and Nordegg."

Jan 1, 1973

By Wei Yingchun

Based on the deep burial depth of coal deposits in Huainan-Huaibei coalfields, Anhui Province, China, this paper puts forward the concept of partitioning of coal deposits according to occurrence conditions. This process is controlled by tectonic forces. The classification scheme of coal deposits exploration types is presented according to occurrence and mining conditions of coal deposits as viewed from the perspective of deep coal exploration properties. The principles underlying geological exploration services for the resources development are incorporated. There are six exploration types of coal deposits in the Huainan and Huaibei coalfields. Exploration models tailored to different types of exploration have been established and exploration strategies corresponding to different exploration models have been proposed. Steady-state temperature must be measured for the deep heat-harm type of coal deposit. The sealing coring of mine gas samples should be performed for the high mine gas type of coal deposit. For coal deposits with complex structures, such as those located beneath nappes, coal-controlling structural styles must be performed. Existing data on shallow districts are very important to the research of folds and fault-block types of coal deposits beneath and peripheral to old and existing coal mine areas. For the types of fault-block coal deposits hidden by thick Cenozoic cover, particular attention must be paid to comprehensive use of research on regional coal occurrence law and geophysical methods. The present work promotes the exploration level of coal deposits in Huainan-Huaibei coalfields to best meet the need for sustainable development of the coal industry.

Aug 1, 2013

Some examples of the results of research projects, conducted in the KOMAG Institute of Mining Technology are presented. Special attention is paid to mining machines and equipment, and improving work safety and comfort of miners in underground workings. From numerous scientific and technical achievements of the KOMAG Institute within the last 2 years, a few design solutions have been selected for a presentation. Some results of European projects on innovative solutions are described as well, highlighting KOMAG?s role in the national and international research area.

Aug 1, 2013

By Frederick Biery

Outline ? Project Challenges ? Results from 100 recent projects ? What factors are driving the best and worst projects ? A look at recent mining projects ? Conclusions

May 1, 2009

By Bob Rappolt

Discussion Points Part 1: Global Mining Industry/Related Issues ? Historical Metal Price Trends. ? Historical LME Metal Stockpiles. ? China?s Demand for Metal. ? World Population Growth, Demands and Development. Discussion Points (cont?d) Part 2: Canadian Mining Industry ? Where are we? And where are we going? ? What progress have we made in the past 20 years regarding: ? Safety -Employee Levels ? Labour -Relative Compensation ? Productivity - Technological Advance ? Where do we stand regarding mineral production? ? What does the future hold for us?

Apr 1, 2005

The AG/SAG circuit discharge P80 is now increasingly referred to as the “Transfer Size” or T80 for short. From the literature it is apparent that in circuit design some approaches to the sizing of AG/SAG mills as well as the ball mills that they feed use this parameter. This paper reviews whether the use of the T80 is appropriate in this context. In the course of the review examples of AG/SAG discharge size distributions measured from range of operating circuits are used to illustrate the arguments made.

Jan 1, 2012