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By C. A. Jeffrey, K. Pearson

The Croft diorite in central England belongs to a suite of Caledonian igneous rocks collectively known as the South Leicestershire diorite complex. Although the intrusions occupy separate outcrops, they are linked at depth to form a single pluton, buried beneath a cover of Triassic sediments (Le Bas, 1972; 1982, Allsop and Arthur, 1983). Both the Caledonian diorites and the over-lying sub-Triassic unconformity have been affected by a complex history of alteration and mineralization which can be subdivided into four stages: (1) deuteric effects, caused by the release ofvolatiles during magmatic cooling; (2) albitization through sodic enrichment; (3) formation of low-temperature laumontite, analcime and calcite veins with associated wall-rock alteration to prehniteand pumpellyite; and (4) sub-Triassic unconformity-hosted base metal, manganese and palygorskite mineralization. Zeolite mineralization occured some 200 Ma later than the intrusion itself, duringpost-Triassic times, as indicated by the presence of a single vein of laumontite and microcrystallinecalcite which cross-cuts the sub-Triassic unconformity surface and enters the overlying Triassic sediments. Evidence from ?uid inclusion work indicates that two ?uids were involved in the deposition of the zeolite veins. One ?uid was initially of relatively high temperature (~100°C to 320°C) and lowsalinity (~0.2 to 5.9 wt% NaCl equiv.), and was probably meteoric in origin, whereas the other wasof relatively low temperature (~41°C to 165°C) and high salinity (~0.4 to 16.72 wt% NaCl equiv.),and is interpreted to represent a basinal brine. During Triassic rifting, thinning and fracturing of the crust, with the possible rise of associated magmas (Halliday and Mitchell, 1984), could have increased permeability and heat ?ow, initiating the circulation of hydrothermal ?uids. Triassic unconformity-hosted base-metal mineralization in Central England is similar to other Triassic-Juras-sic mineralization in Europe (Mitchell and Halliday, 1976).

Jan 1, 1997

By Alan A. Barton

Introduction The Little Long Lac mine is situated in the Thunder Bay mining district, township of Errington, Ontario. The mine is located on the south side of the most westerly bay of Little Long Lac. The property consists of 36 claims, which comprise some 1,400 acres. This group of claims was staked in August, 1932, by Tony Oklend and Tom Johnson, and, after surface sampling, was optioned by the present controlling interests, who diamond-drilled it during the winter of 1932-33. In early spring, a small steam-driven plant was installed, and shaft sinking commenced on June 1st, 1933. During the summer, all supplies are transported to the mine from Hardrock station, at mileage 18 on the Canadian National Railway line from Longlac to Port Arthur. At Hardrock, which is seven miles from the mine, the railway skirts a bay of Little Long Lac, and supplies are loaded directly from railway cars to scows. Two scows are used, of 30-and 45-ton capacity, respectively. A 36-ft. pointer, powered by a 35 h.p. engine, is used as a tug. A good winter-road has been cut out from Geraldton to the mine, for winter transportation. Geraldton is about two miles north of the mine, and is also located on the Canadian National railway. A hard-surface road is now being constructed for summer as well as winter use. Geology The Little Long Lac gold area covers the northern limits of a large synclinal structure, the contact of the Keewatin flows and sediments, striking about twenty degrees north of west, with the dip of the sediments varying from eighty degrees north to seventy degrees south, the average being around eighty degrees south. The vein worked by Little Long Lac Gold Mines occurs in massive sedimentary rock of about the composition of arkosic or quartzitic greywacke, and consists of a shear-zone up to fifteen feet in width, striking N.75°E. and dipping steeply to the south, which has been filled by numerous narrow, parallel quartz veins and. veinlets. These are well mineralized. with arsenopyrite, pyrite, and some chalcopyrite and stibnite, and carry considerable quantities of visible gold. They show more than one age of quartz deposition, the quartz being fractured and re-cemented. The arkosic rocks separating the veins and veinlets are also slightly mineralized with pyrite. Work to date has indicated the probability that the vein-shear is controlled by local drag-folding.

Jan 1, 1935

By Balmer Neilly

Early in my term of office it was announced that my Presidential Address would make particular reference to the subject of Mine Taxation in Canada. With this purpose in view there was drafted a Balance Sheet and Earnings' Statement of a Gold Mining Company. This in turn was submitted to the Dominion Income Tax Authorities in Ottawa and to the Minister of. Mines of each of the several Provinces of Canada. The response to the invitation was not as complete as we had hoped it would be, but the figures that were obtained will be presented during the present meeting, and they constitute, I hope, a sufficient basis for extended study and additional enquiry during the year to come ( 1) . In the form letter that accompanied our request to have the submitted earnings assessed, I made the following assertion: "In this work we have three objects in mind. 1.--We will get direct comparison between the different Provinces in Canada. 2.-We will in this way educate our members concerning taxation as it affects the mining industry. 3.-We will publish the details as to how the assessment is calculated by each body, so that a Mine Manager in the most remote district will have a ready reference to guide him in his annual return to the taxing bodies. As things stand, there is no intention of making this a basis for a critical attack on the present rates assessed. It is intended as an authoritative summary of actual conditions as they presently exist".

Jan 1, 1934

By J. R. Donald

"Project development has been increasingly formalized in the past decade, with most organizations having extensive and descriptive deliverables documents and processes to govern the stage gate progress of capital projects. Although this has improved the general governance of capital project development and execution, it has perhaps not led to improved business success. This paper identifies specific challenges associated with developing complex projects with multiple stakeholder interests over the long timeframe of the project life cycle. The paper outlines these challenges and suggests management approaches and aspects of project development where increased focus is required to achieve improved business outcomes."

Jan 1, 2015

By Dale A. Walters

The thermal recovery of bitumen reservoirs by steam assisted gravity drainage (SAGD) is often designed to maximize the operating pressure. In general, the benefits of higher operating pressures are higher steam temperatures that maximize the reduction of oil viscosity, potential permeability enhancement associated with lower effective stress and shear dilation, and a larger pressure window to allow flexible control of the producer. This is especially important for shallow reservoirs where the pressure window for injection and production is smaller. Higher operating pressure can reduce thermal efficiency (due to heat losses), but the other benefits usually compensate. The limitation of the maximum operating pressure is then based on maintaining caprock integrity. Thus, shear and tensile failure mechanisms must be quantified and managed. This paper presents a geomechanical analysis of caprock integrity for SAGD operation. Both analytical and numerical approaches are used to investigate the modes of caprock failure. Main factors in the analysis are the knowledge of the initial stress state and proper representation of the complexity of the geomaterials. Typical initial stress states for northern Alberta are presented showing the potential for low initial minimum total stress and elevated initial shear stress levels. The stress-strain behavior for the sand and caprock materials is discussed focusing on the potential for shear dilation in the sand and shear strength behavior in the caprock. Elasto-plastic constitutive models used to represent the sand and caprock are presented and compared using numerical analysis. The increase in pressure and temperature alter the stress state and disturb the soil matrix. This disturbance results in shear dilation of the sand matrix creating regions of enhanced permeability and porosity. Also, the transfer of stress and strain to the caprock causes dynamic stress changes and, therefore, dynamic behavior of shear and tensile failure conditions. Calculations are presented showing the stress paths associated with SAGD operations, suggesting better design of lab testing programs and the implications for shear dilation in the sand and shear failure in the caprock.

Jun 1, 2012

By Y. Yhang, D. C. Sego

ABSTRACT This paper evaluates the potential of freeze-thaw dewatering using Albian mature fine tailings (MFT). Freezing tests were first performed to study the effect of freezing rate on dewatering efficiency. Lower freezing rate resulted in higher thawed solids content and shear strength. Subsequently, large strain consolidation tests were conducted to investigate consolidation behaviour and how it is affected by freeze-thaw. The consolidation behaviour was presented in terms of effective stress versus void ratio and permeability versus void ratio. The results can be used to predict the field behaviour of Albian MFT and optimize the application of freeze-thaw for MFT dewatering.

Jan 1, 2014

By F. Siciliano, D. Bai, S. Yue, A. M. Elwazri

The influence of niobium addition and very low temperature (`cool') deformation on the microstructure and properties of low carbon microalloyed steels was investigated. In this work, the specimens were heated at 1200°C and held at this temperature for 20 minutes. Some specimens were aged at 400°C for times ranging from 10 minutes to 10 hours followed by air-cooling. Others were subjected to deformation at 400°C (`cool deformation') prior to aging. It was observed that the proportion of acicular ferrite was increased as the amount of Nb was increased. It was found that cool deformation increased both yield and tensile strengths significantly compared to that of the aged only specimens.

Jan 1, 2005

By J. B. Boisvert, D. S. Silva

"Drillhole placement involves benefits, costs, and constraints. Benefits are related to the drilling campaign value, which includes maximizing “indicated” and “measured” resources. Costs include drilling, rig movement, and access construction. Constraints include infeasible areas, maximum and minimum angles of drilling, maximum depth of drilling, and budget. Manually planning drillholes that meet these constraints is suboptimal. A framework for straight drillhole optimization that accounts for benefits, costs, and constraints is presented. The method aims to maximize the value of resources converted from “inferred” to indicated and measured. The framework is demonstrated for a Nevada gold deposit and outperforms manually selected drillholes.RÉSUMÉ Le choix de l’emplacement d’un trou de forage s’accompagne d’avantages, de coûts et de contraintes. Les avantages sont liés à la valeur d’une campagne de forage, qui comprend l’optimisation des ressources « indiquées » et « mesurées ». Les coûts englobent le forage, le déplacement de l’appareil de forage et la construction des routes d’accès. Quant aux contraintes, elles portent sur les zones impraticables, les angles maximums et minimums de forage, la profondeur maximale de forage ainsi que le budget. La planification manuelle des trous de forage répondant à ces contraintes est sous-optimale. Cet article présente un cadre relatif à l’optimisation des trous verticaux de forage tenant compte des avantages, des coûts et des contraintes. Cette méthode vise à optimiser la valeur des ressources converties de la phase « ressources présumées » à celle de « ressources indiquées et mesurées ». Ce cadre est appliqué à un gisement aurifère du Nevada et donne de meilleurs résultats que les trous de forage sélectionnés manuellement. INTRODUCTIONDetermining the optimum location of infill drilling has been studied because the high cost of drilling suggests that using fewer drillholes is preferred, and targeting locations of the deposit that are locally uncertain should result in better mine planning decisions and increased profit of the operation. Existing methods for optimizing drillhole locations consider minimizing the kriging variance (KV) as the objective and are mostly restricted to two dimensions (Soltani-Mohammadi & Hezarkhari, 2013a, b; Soltani- Mohammadi, Safa, & Mokhtari, 2016)."

Jan 1, 2018

By Gerry Doeksen

The paper deals with three case studies: (a) the handling of wet concentrates (5 to 8 per cent moisture) through feed bins; (b) the handling of the same product in rail cars; and (c) the handling of dry concentrates (less than 0.5 per cent moisture) through feed bins. In each case, the paper discusses the problems of rat-holing. In each of cases (a) and (c), there is a discussion on the consequent extreme variations of feed rates coming from the feeders, making automation of process control difficult to impossible. Currently available bin-flow theory and flow property tests are used as aids in redesigning the bins. The paper concludes with illustrations of the final results after the redesigned hoppers were installed and tested. There is also a discussion on the advantages of the new mass-flow bins on adjacent feeder performance.

Jan 1, 1970

By N. N. Rulyov

"Starting from fundamental principles of colloid-hydrodynamic theory of disperse systems we have shown that application of strongly non-uniform hydrodynamic fields allows to achieve not only faster rates of flocculation of suspension, but also supports significant improvements in the quality of clarified water and separation characteristics of solid phase. Specifically, it has been experimentally proven that the new treatment method based on these principles (then termed as ""ultra-flocculation"") allows:•,Increase the output of thickeners and pressure filters by 1,5-1,7 times;•,Decrease solids fall through into the filtrate in the process of vacuum filtration by 2¬3,5 times;•,Improve the rate of purification of water phase in the upright thickener by 1,5-1,9 times;•,Decrease flocculant consumption by 1,5-3 times;•,Increase the effective operational life time of cloth filters by 3-4 times;•,Ensure sustainable operation of separation equipment, i.e. decrease the sensitivity of process to variation in suspension concentration, as well as to variations of suspension composition and dispersion characteristics;•,Apply flocculant solutions of concentration 2-3 times higher, thus increasing the capacity of equipment used for solutions preparation."

Jan 1, 2004

By J. A. Drozdiak

In this paper we examine, through pilot-scale testing, the possibility of operating a circuit comprised of two stages of HPGR comminution, followed by grinding through a horizontal stirred mill. In order to assess whether the novel circuit design could achieve the reduced energy requirements indicated in the literature, two more-established circuits, a cone crusher / ball mill and an HPGR / ball mill, were examined using a combination of testing and flowsheet simulation. The results showed that, based solely on the specific energy requirements for comminution, the HPGR / stirred mill circuit achieved a reduction of 9.2% and 16.7% over the HPGR / ball mill and cone crusher / ball mill circuits, respectively.

Jan 1, 2012

By J. Paraszczak

High productivity of the equipment employed is one of the key factors in reducing production cost in mining. One of the best ways to achieve it is an increase in availability. In order to identify the most adverse factors affecting it, reliability and maintainability analysis ought to be done. If its results are to be conclusive, a sufficient amount of credible and consistent data is indispensable. Following the experience from field studies done in underground mines, this paper discusses the current status of failure and maintenance reporting, as well as problems encountered. It exposes the importance of adequate data collection on failures and downtime as well as it reviews the benefits of analysis based on such material. The question of benchmarking with regards to mining equipment performance is also addressed. The paper concludes with some recommendations on data collection and processing, as well as stresses the need to standardize the most important reliability/ maintenance notions throughout the mining industry and to conceive appropriate performance measures.

Jan 1, 2000

"The pressure leaching of alkali-pretreated limonitic laterite ore in nitric acid was studied. The optimal leaching conditions are as follows: leaching temperature of 458 K, initial nitric acid of 2.44 mol/L, leaching time of 60 min, liquid to solid ratio of 2:1 mL/g, agitation speed of 500 RPM. Under the above conditions, the extraction of nickel and cobalt can be achieved as approximate 95% and 80% respectively while that of iron is as lower as 1%. The leaching residue containing 70% of iron in the form of hematite and trace amount of chromium is suitable as the raw material for iron-making. The nitric acid in the leaching solution can be regenerated and further recycled to leach. INTRODUCTIONIt has been estimated that 60%-70% of the world land-based nickel resources presented in nickel laterites containing 130 million tons of nickel although these only accounted for about 42% of the world nickel production (Sudol, 2005; Luo et al., 2010). The nickel resource of laterite has not yet been fully utilized. Due to the increasing global demand of nickel and the declining global reserves of nickel sulphides, there is an increasing focus on the processing of the huge reserves of laterite ores today. Nickel laterite ores can be simply divided into two types, namely, silicate-rich and limonite. The former can be treated effectively by pyrometallurgical process in which the ferronickel product or nickel/iron sulphide matte is produced (Monhemius, 1987). The limonitic laterite is rich in iron in the form of goethite which is the main nickel-bearing mineral and usually contains cobalt associated with a manganese phase (Chang et al., 2010; Georgiou and Papangelakis, 2004). The limonitic laterite is usually processed by hydrometallurgical methods, such as atmosphere acid leaching (AL) (Xu et al., 2005; McDonald and Whittington, 2008), high pressure acid leaching (HPAL) (Chou et al., 1977; Georgiou and Papangelakis, 1998; Rubisov et al., 2000; Whittington and Muir, 2000) and reductive roasting-ammonia leaching (Caron Process) (Whittington and Muir, 2000; Valix and Cheung, 2002). The AL process can proceed at lower temperature, thus the operation costs may be very low. But two biggest problems associate with the AL process, namely, the slow rates of nickel extraction and potentially the significant amount of impurities such as iron and aluminum in the leaching solutions, which hampers the wide application of the AL process. The Caron Process uses the pyrometallurgical and hydrometallurgical methods together to obtain the metallic values, but the overall metal recovery is relatively low, especially for cobalt. In recent years, the environment-friendly process of HPAL has become increasingly important because it is most suitable for low-grade ores and leads to high extraction of the valuables. However, the HPAL process needs a much higher temperature and pressure (503-533 K, 4-5 MPa) to maintain a relatively fast leaching rates, which results in higher operation costs. Moreover, another serious problem of scale formation in autoclaves occurs in the HPAL process, for example, in Moa Bay, up to 20 cm scale may build up resulting in 5 days descale downtime per month. In addition, the iron residues cannot be utilized for ironmaking due to the presence of high content chromium (Ema and Harada, 1987; Owada and Harada, 1987; Takagi and Furui, 1987)."

Jan 1, 2012

By Saravarim A.

"The aim in flotation systems is to control the grade and recovery of the product., numerical method or sampling and analysis is used to achieve this goal. Weakness of measuring instruments, lack of process knowledge, deficiencies in management and data processing in the control of flotation cells, has led the academic and industrial units to use numerical models. In this regard, using the results obtained from the experimental design carried out in the DTP line of Gol Gohar industrial and mining complex, a regression model was developed based on the analysis of variance. To present this model, after variance analysis of factors and interactions, all models were investigated and the final model was created based on 75% of the data. The model was tested with the remaining 25% of the data to confirm the goodness of the fit. The coefficient of determination for training and testing resulted 71% and 74%. Moreover, a feed forward back propagation neural network with different layers and neuron was used to model the results. The best network structure was 6-27-1 and the coefficient of determination for this network was 99% and 98% for training and test respectively. Given the complexity of neural network models and the relatively low accuracy of the regression model, neural network has a priority assuming we have access to a specialist. In addition, the results obtained from neural network can be used as expert systems to control and optimize the flotation cells.INTRODUCTIONThe primary objective of the flotation cell control is to maintain the product's (in this case tailing) recovery and grade, which represents the index for process efficiency and product quality. Continuous estimation of these indexes requires a significant amount of maintenance, and calibration of the continuous analyzers, in order to maintain an acceptable level of accuracy. Weakness of measurement equipment, lack of process knowledge and the general deficiency in management and processing of data in the flotation cell control, will lead industrial units to use smart methods such as mathematical models, regression and neural networks in near future (Panahi, Abdollahzadeh, & Sam, 2010). Artificial neural networks are inspired by the very complex structure of human brain in which millions of nerve cells solve problems or store information by communicating with each other. The duty of neural networks learning. It should be noted that learning in artificial neural networks is limited, and what is practically considered is the computing power of the network. A neural network consists of units called neurons, and has the capacity to handle a set of input data to produce a desired output data set. Each of these input and output data sets can be assumed as a vector (Soltanmohammadi & Noparast, 2006)."

Jan 1, 2016

By W. A. Roliff

The renewed interest of the past few years in the Appalachian and Michigan oil provinces has not, as yet, created any marked increase in activity in Southwestern Ontario. During 1960 development drilling in-creased somewhat over 1959, but exploratory drilling decreased slightly. More attention was devoted to the deeper horizons, but lake drilling de-creased considerably. Oil production reached a new peak and gas production increased slightly. During 1960 an interesting oil and gas discovery was made in the Cambrian and gas discoveries six miles off-shore in the eastern part of Lake Erie were made in the Clinton-Cataract zone of the Silurian. This paper reviews activities during 1960, summarizes the discoveries made to-date and the pertinent exploration data relating to the prospects of the region and discusses some of the economic aspects of exploration and development. D URING the last few years there has •been a marked renewal of interest in the old petroleum

Jan 1, 1961

By W. J. Dick

THE purpose of this paper is to point out, briefly, the importance of the coal mining industry of Alberta and to stress the economic factors that hinder its development; also to offer suggestions relating to the major problems of the industry. The minor problems will not be dealt with in detail, because, if the major problems are taken care of, it is felt that the industry itself can take care of ,he remainder. COAL MINING NO LESS IMPORTANT THAN GOLO MINING The large increase in metal mining development in all provinces of Canada, excepting Saskatchewan, Alberta, and the Maritimes, has had the effect of focussing public attention on this branch of the industry. The fact, also, that this development came at a time of depression has been of immense benefit to Canada as a whole. On account of the necessity and consequent demand for gold, with its attendant increase in price, through government action, from $20.67 per ounce to $35.00 per ounce, it is safe to say that the public of Canada have become, today, gold mining conscious. While everyone admits the great value. of the gold mrn111g industry, nevertheless, the equal value to Canada of certain other industries must not be lost sight of. The coal mining industry, in particular, is worthy of greater public and government support than has been accorded it in the past. It would seem unnecessary to stress this matter to a meeting of the Canadian Institute of Mining and Metallurgy, but unless certain facts are brought to your attention, there is danger that the coal mining industry will not be developed to the extent its national importance deserves. Too many public men and men in authority are unaware of the value of coal mining.

Jan 1, 1936

By G. Anger, J. Enser, H. Antrekowitsch, S. Koch

Homogeneous chemical composition and microstructure are always necessary, but not always attained in practice. As-cast aluminium alloys tend to have a segregation microstructure. Features of the cast structure, which affect subsequent processing or properties, can be altered by the homogenization. The main task of the Department of Nonferrous Metallurgy was to investigate the effect of homogenization treatment on precipitation hardening of aluminium alloys 6061 and 6082. The effect of the solution heat treatment (SHT) temperature on the mechanical properties was also analyzed. The homogenized and non-homogenized rolling slabs were produced according to the usual conditions and methods. The metallographic investigations were carried out on the as-cast samples, after homogenization, after the hot and the cold rolling mill, and after natural and artificial ageing. Then, Brinell hardness measurements and tensile tests were conducted on both alloys in order to examine the influence of the homogenization.

Jan 1, 2006

By E. M. Cameron

Reconnaissance radiometric and geochemical data have been obtained for an area on the western shore of Wollaston Lake that includes the Rabbit Lake uranium deposit. The study area is extensively drift cover ed. The geochemical data were obtained by analysis of center-lake sediments and surface waters for a variety of elements and other constituents. The airborne radiometric data comprise measurements of eU, eTh and K obtained with a .50,000-cc NaI (Tl) detector at a mean terrain clearance of 120 m and 5-km flight-line spacing. Uranium in lake sediments and uranium in waters are the most effective geochemical indicators of uranium mineralization; the other elements measured are not notably anomalous. A sample site density of one per 1 8 km 2 is more than adequate for identification of the mineralized area. Because many water samples contain close to or below the current analytical detection limit of 0.05 ppb U, the use of sediments is generally favoured. for broad-scale reconnaissance in the region. Uranium in these lake sediments appears to be little influenced by variations in the organic or iron and manganese content. The most effective radiometric indicator of the mineralization is the eU/eTh ratio. This parameter is less influenced by environmental variation on the ground beneath the flight line than eU alone . The eTh/K ratio is anomalous under the Athabasca Formation unconformity where, in places, the uranium mineralization is localized.

Jan 1, 1977

By Adrian Dance

Barrick Gold Corporation?s wholly owned subsidiary, Barrick (Granny Smith) Pty. Ltd. operates the Granny Smith operation in Western Australia and has been operating a SAG/ball mill (SABC) circuit for a number of years processing a blend of secondary crushed, open pit and underground material. With closure of the open pit in 2008, Granny Smith was considering different options to process underground only material at a lower throughput. Using the existing equipment available on site, a number of circuits were evaluated by Metso Process Technology & Innovation (PTI) through modelling and simulation. A single stage SAG mill circuit was selected based on power requirements and operating efficiency. In April 2008, Granny Smith started operating their SAG mill in single stage, processing primary crushed feed and using their existing pebble crusher for scats. Smaller cyclones were used to control the final grind size. PTI surveyed the new single stage circuit in July 2008 under normal and high rock load conditions to show the effect on final grind size. Granny Smith continued to operate this circuit until the end of 2009, when alternate feed sources resulted in a return to the complete SABC circuit at a higher tonnage once again. The variable speed, single stage SAG mill proved itself to be very efficient and flexible option to process the hard underground Wallaby Deeps material. This paper will review circuit performance following the conversion to single stage in comparison with the full SABC circuit.

Jan 1, 2012

By Fatemeh Saeidi, Luis Marcelo Tavares, Malcolm Powell, Mohsen Yahyaei

"Understanding a single breakage mechanism is fundamental to the development of breakage testing techniques appropriate for mechanistic modelling of any breakage equipment. In the light of this insight, it is also possible to compare any two breakage events in a mechanistic manner. This paper presents a new method to compare breakage mechanisms of two-point impact with compression, different in their applied strain rates. This approach regards a single breakage event as a process affected by three sub-processes; first fracture, capture and spatial distribution of fragments. Spatial distribution is influenced by the kinetic energy of fragments and their brittleness. Using this methodology allows us to examine how each sub-process is influenced by applied strain rate and its impacts on progeny size distribution. For this purpose, two rock types of widely different strength, magnetite and silicate, were tested at various energy levels using the impact and compression mechanisms. To isolate the effect of spatial distribution of fragments, particles were forced to remain in the breakage zone. In this condition, similar progenies were generated from compression and impact mechanisms at similar energy levels. However, allowing natural distribution of fragments, coarser progeny was produced from compression of silicate. Additionally, using this approach provides a physical meaning and explanation for rock strength parameters such as A×b in the t10-Ecs relationship. INTRODUCTIONComminution models are rapidly progressing toward a destination that enables us to explain the complete physics of a breakage process as well as the properties of the ores. Eventually, they will be able to take into consideration the micro-events that take place during the comminution process (Bourgeois and Banini, 2002). Thus, considerable efforts have been made in the last few years in the area of ore breakage characterisation to comprehend and unlock a single breakage process that has been treated as a black box event in the majority of conventional methods. In this paper, an attempt is made to explain the effect of applied strain rate on the breakage properties of rock by using the knowledge that has been gained by understanding a breakage event. This is particularly important due to its application for various comminution devices that operate within a relatively broad range of speed."

Jan 1, 2016