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By Yuan She, Qihang Liu, Keng Wu, Hailiang Ren

By observing different coal char’s microstructures and microscopic morphologies during the coking process, the characteristics of COREX coal char’s microstructure and properties were analyzed. MCRI and MCSR were used to respectively describe the reactivity and the strength after reaction of coal char, with those of BF’s coke for reference, and then the physical meaning of MCRI and MCSR were given. MCRI and MCSR were determined by the composition of coal char. For the two kinds of COREX coal, the formula to forecast the hot performance of coal char was set up by making a multiple linear regression between the hot performance and microstructure of the coal char at 1100℃, and the predictive values of coal char’s hot performance at 600℃, 800℃ and 1000℃ coincided well with the measured values.

Jan 1, 2015

By C. B. Carelse, M. Manuel, D. Chetty

Automated mineralogical analysis of platinum group minerals (PGM), using the mineral liberation analyser, provides information used to understand flotation efficiency, primarily from a PGM liberation and association standpoint. To date, however, there is no consistent understanding regarding PGM speciation and its impact on floatability. Previous studies of PGM from UG2 ores concluded that a larger dataset is needed from which the various parameters can be modelled. Parameters on telluride, arsenide, sulfurarsenide and alloy species need to be integrated to fully understand the impact of PGM speciation on flotation, and for this, ores other than PGE-sulfide-rich UG2 must be assessed. Flotation rougher rate tests were performed on feed samples from two Platreef ores to determine the flotation response of individual liberated PGM species. This was achieved through automated mineralogical analysis of feed, rougher concentrates and tails. Based on 1529 liberated PGM grains assessed over the circuit for two Platreef ores, preliminary results show that PGM speciation, species grain size and competition from gangue appear to influence floatability in an ‘optimised’ laboratory environment. Keywords: PGM, PGM species, flotation, liberation

Jan 1, 2020

By Patrick Mclaren, Peter B. Hale

Canada, with one of the largest continental shelf areas in the world, has done little to evaluate its offshore unconsolidated mineral resources which include heavy minerals (gold, chromite, rutile etc.) and industrial minerals (silica sand and aggregates). During glaciation much of the continental shelf was covered with an ice sheet and later subaerially exposed with the result that glacial, glaciomarine and fluvial processes deposited sediments that may contain heavy minerals derived from onland locations. With rising sea-levels, beach and nearshore processes may have served to concentrate heavy minerals by winnowing and removing the lighter mineral components. These potentially valuable resources can be found with suitable exploration techniques such as seismic profiling and bottom sampling. Gold deposits are known to exist off the coast of Nova Scotia, and on the basis of form er beach mining, gold deposits probably occur off Vancouver Island and the Queen Charlotte Islands. Large deposits of silica sand occur near the Madeleine Islands and it appears likely that supplies of marine aggregates are present close to urban markets or sites of future mega-projects such as oil field developments. This paper, which is based upon a review of literature and consultation with members of the Department of Energy, Mines and Resources' Coordinating Committee on Ocean Mining (DCOM), is the first step in assessing the Canadian offshore f or its resource potential with respect to quantified deposits, known and speculative mineral occurrences. Although this is a subjective evaluation, the potential appears promising. A more detailed resource inventory is required to provide a more certain assessment.

Jan 1, 1984

By Ting Lu, Gerard Laman

"This document compares the systems of coal classification described under ASTM standards used in Canada to GB standards used in China. A preliminary connection of metallurgical coal classes was set up between the two classifications. In GB classification system, there are nine metallurgical coal groups, namely PS, SM, JM, FM, ½ ZN, RN, 1/3 JM, and QM used in coal blending for coke production. PS coal is almost equivalent to the Low Volatile Bituminous coal; SM, JM, and FM coal groups fall into Low to Medium Volatile Bituminous range; ½ ZN, RN, 1/3 JM, and QM are equivalent to bituminous coal with medium to high volatile matters; QF contains higher volatile bituminous coal compared with High Volatile Bituminous coal. The caking properties commonly used in respective country are also compared in this document. These properties include free swelling index (FSI) and maximum fluidity used in Canada, as well as caking index (GR.I.), and the maximum plastic layer thickness (Y) mainly employed in China. It has been observed that the log of the maximum fluidity has a stronger correlation with the caking index than the Y values. Metallurgical coal processing strategy and typical coking coal product qualities are briefly discussed in the last section of this paper. Currently there is a trend to use heavy medium cyclone in both countries. In Canada the conventional two-product cyclone technology is the preferred practice; whereas in China the three-product heavy medium cyclone arrangement is widely used.INTRODUCTION Coal can be simply classified by applications into two categories: i) thermal coal used to provide heat energy in combustion, and ii) metallurgical coal which is converted to coke, in a carbonization process, and used mainly in the iron and steel industry. Metallurgical coal contains even higher heating values than thermal coal. In addition, it presents unique plastic properties during carbonization which in turn produces a porous solid, high in carbon referred to as coke. Coke is one of the most important raw materials in the iron and steel industry."

Jan 1, 2012

By K. D. Luxbacher, E. C. Jong

Perfluoromethylcyclohexane (PMCH), a member of the perfluorocarbon tracer group of compounds, has been shown to be a viable supplement to the widely used tracer gas sulfur hexafluoride (SF6). This viability stems from the fact that PMCH can be used concurrently with SF6 while maintaining adequate chromatographic separation and comparable sensitivity during analysis. However, the release of PMCH in an underground mine ventilation system is challenging due to its physical characteristics. While SF6 exists as a gas at room temperature and pressure and can be accurately released by a variety of means, PMCH exists as a volatile liquid at room temperature and pressure, preventing it from being deployed in a similar manner. One method to release PMCH is to use a permeation plug passive release vessel (PPRV), which allows for the controlled release of the gas. This paper presents the results of a study evaluating various preparation techniques, plug thicknesses and plug materials of an aluminumvessel PMCH release source, so that a source appropriate for the mine scale may be developed.

Jan 1, 2015

By J Taylor, L Richards, M McKenzie

When a collapse in its services shaft caused rapid gas build up and its premature closure in. 1951, the Blackwater Mine at Wiauta was in full production with significant ore reserves yet to be mined. A total of nearly 23 tonnes of gold was produced from the mine during its 44 year life. It was New ZealandÆs deepest underground mine, producing gold from an extensive sub-vertical mineralised quartz reef that averaged 0.6 m in width. Mining was by stoping between adits and short shafts, latterly with the main mine access through the 840 m deep Prohibition shaft. Macraes Mining Company Ltd are presently investigating the possibility of reopening the mine. This paper outlines a preliminary assessment of the main geotechnical factors for achieving the reopening, using recent exploration and old mine information. The greywacke host rock mass in the vicinity of the quartz reef has been evaluated using both these sources, and the paper discusses how the geological structure, intact and rock mass strengths, the rock mass defects, in situ stresses, and groundwater inflows may effect the reopening and support of the prohibition shaft, the excavation methods and support for a new supplementary shaft, and the likely excavation and support requirements for working adits and stopes in the rejuvenated mine.

Jan 1, 1996

By Chappell B

Backfill in the form of mine waste tailings has inherent problems associated with attaining adequate strengths upon placement. Fines are usually removed to ensure adequate drainage, which lowers the cohesive strength of the fill, leaving the fines to he placed in a tailings darn. Electro-drainage and electro-chemical grouting is examined to investigate its effects on densification and shear strength within a silty clay tailing having low permeability and shear strength. Two separate grouting mechanisms are observed for the iron and silica grouts used. Electro- osmosis is associated with iron grout that deposits within the tailing matrix under a converging pH gradient, and increases the permeability of the tailing. This process initiates cation exchange and causes cementing of the granular contact points between the clays. Electro-phoresis causes sodium silicate solution to deposit silica grout in the voids of the tailings. The resultant effect of these mechanisms results in an increase in cohesion, leaving the void ratio of the iron grouted tailings as it was but significantly reducing the void ratio of the silica grouted tailings.

Jan 1, 1998

By F. Peer

This Technical Note was presented as a poster at the Western Cape Mineral Processing Symposium held in August 2001 The cleaning of fine coal (-1000 µm) in today?s coal preparation plants is an economically important factor. Coals with high ash contents are, in general, commercially undesirable. Current well-known techniques for treating fine coal include froth flotation and spirals. The primary critical factor with regards to spirals is the efficiency of the process whereas that of flotation, is the cost of there agents used. Research into enhanced gravity separation techniques has resulted in several commercially available enhanced gravity separators. This project was based on a preliminary investigation into the feasibility of one such separator, to effectively treat fine (-500 µm) coal. Experimental variables included particle size and speed of rotation of the said instrument. The performance of the separator was compared to the results obtained from liquid density separations done for the two coal fractions evaluated. From the results obtained in this preliminary study it appears that the piece of equipment investigated does not measure up to expectations. Recommendations for further investigation include the evaluation of the instrument on other South African coals to obtain conclusive results.

Jan 1, 2002

By L. Frost

"Since the late 1990s, increased prevalence of severe lung disease among US coal miners has been observed, particularly in central Appalachia where thin-seam mining is prevalent. While respirable silica exposures have been implicated in many cases, the available dust monitoring data from mines shows no explanatory trends. One possible factor could be differences in the relative toxicity of silica particles based on their surface condition. Previous research has indicated that particles with occluded surfaces (e.g., by a thin layer of clay) may be less toxic than those with non-occluded surfaces. However, this dust characteristic has not been investigated before now in central Appalachian mines. In the present study, 18 respirable dust samples from seven central Appalachian mines and two northern Appalachian mines were analyzed to assess the relative occurrence of surface-occluded silica. Results showed that the dust from central Appalachian mines actually had higher fractions of occluded silica, which may be due to extraction of large amounts of rock strata along with the coal. However, the central Appalachian mines also more silica particles overall (i.e., occluded + non-occluded) in terms of total number percentage of respirable particles.INTRODUCTIONResurgence of occupational lung disease among US coal miners, especially in the central Appalachian region, has been observed since the late 1990’s (Gibson, 2016; Zosky et al., 2016; Suarthana et al., 2011; Gamble et al., 2011; Antao et al., 2005; Attfield & Sexias, 1995). In addition to increased prevalence of simple Coal Workers’ Pneumoconiosis (CWP, or “black lung”), the prevalence of severe and rapidly progressive disease has risen dramatically (Almberg et al., 2018; Blackley et al., 2018a, 2018b, 2016, 2014; Graber et al., 2017; Cohen et al., 2016). While exposures to respirable silica have long been known to cause or play a role in diseases such as silicosis or progressive massive fibrosis (PMF), which is conventionally considered as the most advanced form of CWP, it is unclear whether silica is the only culprit in the recent outbreak of severe disease. Indeed, as disease rates have risen, both total respirable dust and silica concentrations generally appear to have declined since the late 1980s, based on regulatory monitoring data in the most affected mining districts (i.e., MSHA coal Districts 4, 5 and 12, which cover central WV, eastern KY and southwestern VA, and southern WV, respectively) (Figure 1). Of course, the latency of disease can vary and may be or more 10 years, but many of the most recent cases are likely to have resulted from exposures that occurred since the late 1980s."

Jan 1, 2019

In 1961, West Australian Petroleum's Eneabba No. 1 bore encountered 22 seams of coal totalling 40 ft in thickness between the depths of 6373 ft and 6441 ft. On analysis, this coal had a similar calorific value (8000-HOOO B.T.U./lb, assuming 20 per cent water) to the coal from the Collie Coalfield, Western Australia's only known area of commercially exploitable coal. Being buried to depths in excess of 6000 ft, the coal at Eneabba had developed weakly-coking properties, and thus, although much younger than the Permian coals of Collie, gave promise of being a major potential source of power for Western Australia.West Australian Petroleum undertook a programme of stratigraphic drilling and shallow test drilling to determine whether this coalhorizon persisted into the outcrop of the Lower Jurassic sediments in the Hill River district, 140 miles NNW. of Perth, and, if it was present, if the quality and quantity of the coal would warrant development of the deposits by open cutting. The coal horizon was identified in the near surface, but the poor quality of the coal and the complexity of the structure made development (in the area examined) uneconomic at the time.A strong seismic reflection in the Eneabba area occurs at the same depth as the Jurassic coals. This event originates within the upper beds of the Lower Jurassic and it is probable that the velocity contrast between the higher velocity siltstones and the very low velocity coals enhances this very strong, distinctive seismic reflection.This event can be followed on continuous seismic data over a large area of the northern Perth Basin, from 13 miles SE. of Dongara to 20 miles SW. of Coorow. It can be followed from a depth of 4000 ftnear Dongara to over 17,000 ft to the SE., so development of thisvast potential source of power will depend on the economics ofprocesses being developed for the production of power from theburning of coal seams in situ.INTRODUCTIONThe discovery of 22 seams of economically useable coaltotalling 40 ft in thickness in the Lower J urassic sedimentsof the Eneabba No. 1 bore (Fig. 1) led to the search forthese seams at economically workable depths. The Ministerfor Mines in Western Australia granted to West Australian1. Supervising Geologist, West Australian Petroleum Pty. Ltd.Manuscript received at The Institute, 25th May, 1964. and presented to the 1964Annual Conference.

Jan 1, 1964

By S. H. Penn

One of the more challenging aspects of the unfolding age of space travel centers about the opportunity for man to use the natural resources of other worlds. The first of the extraterrestrial worlds to be exploited will be the moon. After only a scant few thousand years of scratching the earth's crust, man will embark upon a venture that for centuries has excited the imagination of many (while staggering that of most) and may become a reality within the next decade. There has never been a time when so much money and effort will have been expended to exploit an area about which so little is known. Paradoxically, this effort combines much of the detached objectivity so typical of our analytical time with the proverbial optimism of the indefatigable prospector. As the earliest manned lunar missions will be brief and exploratory in nature, astronauts will not be expected to attempt to exploit any of the possible lunar natural resources. In later missions, with a more extended period of time available for the astronauts to stay on the moon, it may be desirable or even necessary to "live off the land". The resulting exploitation of lunar resources will be intended primarily to reduce the dependence of manned missions upon terrestrial logistic support and to reduce the cost of maintaining lunar bases.

Jan 3, 1966

By Spottiswood DJ, Kelly EG, Bull WR

An empirical model of a 254mm water-only cyclone treating minus 17001im coal has been developed. The model includes the prediction of by-passing, SG50 corrected, water split and the use of a single equation forthe reduced performance curve of particles in the range 1700-106pm. Particles finer than 106pm did not separate according to specific gravity. Simulations using the model showed the water-only cyclone performance to be dependent more upon feed size distribution than washability when the feed contains high-ash fines, but that, with a deslimed feed, the yield and ash content of the over-flow should be controllable by altering feed rate or feed pulp density.

Jan 1, 1985

By A. C. Hawken, L. M. Strah

"The Report outlines the Conversion to Rubber Mill Liners and steel grinding balls from the old style Cobalt pocket liners and flint pebbles which had been used in 5'x22' Fraser-Chalmers tube mills for over fifty years. An outline of the past history and some of the plant modifications are mentioned as well.The details pertaining to considerations, modifications and repairs carried out on the mills are described. Factors influencing the rubber liner design are outlined along with the description of the rubber liner design.The performance and advantages to date are given and concludes with brief summary.HISTORYThe original amalgamation-cyanidation mill of Dome Mines Limited went into operation in 1912. Milling has been continuous since 1912, except for two periods; one of 17 months commencing in December 1917, and the other of about 12 months, when fire destroyed the plant in November 1929. Initially the capacity of the mill was 350 tons a day. In 1916 it was raised to 750 tons a day, following which there was a gradual expansion to 1,500 tons a day."

Jan 1, 1977

By Richard B. Moore

This bulletin presents a summary of available information regarding the sources of uranium, radium, and vanadium, the methods used in treating the ores, and the uses of the finished products. In particular the paper describes the ores found in the United States, giving especial attention to those characteristics of the ores and the conditions of their occurrence that affect mining and treatment. ACKNOWLEDGMENTS. In the preparation of this bulletin a number of persons rendered assistance by furnishing information and by making it possible for us to visit the carnotite deposits in western Colorado and eastern Utah at a time of the year when without this assistance it would have been difficult to obtain satisfactory results. We desire to express our thanks to the following persons: Henry Hall, W. L. Cummings, T. V. Curran, K. D. Hequembourg, David Taylor, H. C. Brown, Forbes Rickard, George W. Alsdorf, Dr. Herman Fleck, Orr J. Adams, C. S. Cherrington, Newt. Stewart, O. B. Willmarth, Angus Cameron, George A. Head, and Lorimer Bros.

Jan 1, 1913

By W. J. Birch, R. Farnfield, L. Bermingham

Whilst a significant body of research has been carried into air overpressure levels that arise as a result of the use of explosives, few published studies have actually tried to relate the movement of a quarry face to the resulting air overpressure produced. The aim of this preliminary investigation was to monitor a number of quarry blasts at two different limestone quarries. The first using multiple separately initiated deck charges in a multi borehole blast, the second using single column charges in a multi borehole blast.

Jan 1, 2008

The ventilation conditions at the underground coal mines are influenced; first: by the disturbances of the natural nature (barometric pressure, methane liberation, etc.), and second: by the disturbances caused by the production process. The major goal of this study was to determine the changes of the ventilation parameters, such as the flow, pressure and methane concentration around the longwall panel, particularly, along the longwall face due to the shearer operation (motion). It is well known from the practice, that the movement of the shearer influences the ventilation parameters around the longwall panel, including the gob area. Until now, these data were gathered in a single or multiple locations at the different time. However, only the simultaneous measurements of all of these values allow seeing the time dependent interrelationships between measured parameters. To be able to show these interrelationships, special experiments, described in this paper, were carried out by the author. These experiments were prepared and executed at the BUDRYK Coal Mine in Poland. During each experiment a simultaneous measurements and monitoring of the barometric pressure, air velocity and methane concentration at the different locations along the longwall face, were performed. The investigation was possible by using a special setup of instruments with a short sampling time, i.e., within 2 seconds. The monitoring of the absolute pressure was conducted by using the digital barometer µBar, developed by EMAG, based on the SETRA pressure transducer, model 470. The velocity of air was measured using the electronic vane-anemometers, developed by IMG-PAN. The methane concentrations were measured using methanometers as the part of the EMAG automatic gas monitoring system. The investigation data confirmed that disturbances due to the operation (motion) of the shearer at the longwall face have a local character. It could be also seen that a large diameter shearer (compared to the total cross-section area available for the air flow) is acting as the piston compressing the air (the overpressure) ahead of the shearer. This fact affects the methane mixing process and flow patterns in the vicinity.

Jan 1, 2009

By B. Li

"The spontaneous combustion of coal storage pile(Gangue Hill) is one of the seriously threat encountered in coal mining and storage. The dynamic accumulation of internal heat in coal storage pile(Gangue Hill) provides continuous heat-source for coal spontaneous combustion. Combined with the features and characteristics of coal pile storage, a technology of heat pipe(HP) is applied to enhance heat transfer. In order to prevent spontaneous combustion of coal storage piles (hillock) due to regeneration, a method using heat pipes to destroy the heat preservation conditions of coal storage pile(Gangue Hill) is proposed, which reduces the risk of coal spontaneous combustion and prevents coal fire. A theoretical model of Coal-Thermosyphon has set up to analysis the radius of cooling effect area quantitatively. An experimental equipment of the heat transferring in a set of heat pipe, which used to study the influence on coal pile temperature distribution, has been designed. Results show, the heat pipe has a significant effect on inhibiting the coal spontaneous combustion process by destroy the heat preservation conditions of the coal. Under the experimental conditions, the most obvious coal temperature decline appears at radius 20.0mm around the pipe, dropped from 45.8? to 32.5?, a decline of 29%; the coal pile temperature at radius 420mm from 12.9? to 12.4?, a decline of 3.87%. And the research offers an effective and new approach in its application and promotion for preventing and controlling in coal spontaneous combustion.INTRODUCTION China is one of a few countries which utilize coal as the major source of energy in the world, and is the one whose characteristic of energy structure is rich coal, deficient oil and lean gas. Relatively speaking, China is abundance in mineral resources. The coal, which is the fundamental resource in the process of industrialization, is the main energy in china. Thus China cannot alter the situation of coal consumption dominated a leading role in its energy structure in near term.A massive of coal gangue would be produced every year in China with the mining activities. And it’s estimated that almost 360 million tons gangue were dumped in 2003, accounting for 10 percent of the whole coal production. Huge numbers of coal waste piles have more than 2,600 seats, which cover an area of over 12,000 hectares. Worse more, the coal gangue still has an annual growth rate of 100 million tons. Toxic smokes and greenhouse gases are discharged directly and prolongly into the atmosphere due to coal gangue spontaneous combustion. Even worse, waste dump explosion cause massive losses and are able to endanger the safety of workers. For example, one waste dump of the NO.4 Mine of Pingdingshan Coal Group Co., Ltd. occurred twice of explosions in 2005, and about 3.13 million tons of waste rocks were thrown within the range from 100 to 300 meters, eight people were killed and 122 rescuers and miners were burned, and economic losses were estimated more than 3,000 million."

Jan 1, 2015

By Edward H. Eisenbrey

This paper is primarily concerned with the exploration for massive sulphide orebodies. In a discussion of this type, it seems appropriate to establish a few definitions so that all parties may consider the same beast and its habitat. First, the term "massive sulphides", as used here, not only denotes a body of mineralized rock containing in excess of 50% sulphides by volume, but a mass of sulphides that respond as a conductor to the electromagnetic (EM) systems currently in use in exploration. "Disseminated sulphides" refer to all of those sulphide occurrences that respond to the Induced Polarization (IP) geophysical methods most commonly in use in porphyry copper exploration. This latter definition may also include the disseminated sulphide halos so frequently found associated with massive mineralization as well as banded and stringer sulphide mineralization. It is plain to see that these two end members of our definitions can easily blend into each other. The term "volcanogenic" refers here to any and all geologic processes that have their origin in volcanic activity. Thus we are concerned here with the exploration for massive sulphide ore deposits derived from and affected by contemporaneous and post mineral volcanic activity. Furthermore, most massive sulphide deposits are apparently formed in a submarine environment, deposited with extrusive rocks and sediments and/or chemical hot spring accumulations, then enclosed and protected by the addition of more volcanic and sedimentary material then, probably folded and deformed into one of their myriad of shapes.

Jan 1, 1973

By Robert D. Brown

"The Conservative Government 's budget proposals brought forward on December 11, 1979 have been withdrawn, but they are far from dead. On the contrary, a number of those budget proposals, especially the ones which would close loopholes and result in other technical changes being made to the Income Tax Act, should be considered to be alive and well.It is not unreasonable to expect the next government, of whatever political persuasion, to reintroduce many of these technical changes in the next federal budget. For that reason, last December's budget may have offered an interesting preview of what the mining industry and other taxpayers can expect in 1980. It is quite possible that some of these changes may be effective as of the original dates announced in the withdrawn budget proposals.This month, ""Tax Notes"" reviews the main pro visions of Mr. Crosbie's December, 1979 budget, with a primary focus on the changes that would have affected the resource sector.It must be emphasized that all of the budget proposals discussed herein have been withdrawn, that none of them are law and that any actual changes in our tax rules will have to be dealt with by the new Parliament that will be assembled following the February 18 election. December 1979budget withdrawnThe federal budget proposals brought forward by Finance Minister John Crosbie on December II, 1979 were withdrawn as a result of the defeat of the Conservative Government on a motion of non-confidence in the House of Commons on December 13. However, it appears quite possible that at least some of the proposals may be introduced into Parliament at a future date, possibly with retroactive effect.In a press release issued by the Department of Finance, Finance Minister John Crosbie stated that if the Conservative Government is returned to power, it will reintroduce all of the measures contained in his December II budget.Mr. Crosbie stated that all of the income tax measures contained in the budget would be reintroduced, effective on the dates indicated in the Notice of Ways and Means Motion tabled on December II. Some of the more important measures in December II budget, and their effective dates as indicated in the Notice of Ways and Means Motion, are discussed below.The December budget had also introduced or increased excise taxes or duties on gasoline, wines, cosmetics and photofinishing. If the Conservative party is re-elected, these measures will be reintroduced with prospective effect (i.e . effective as of new dates to be announced in the new budget)."

Jan 1, 1980

By Lawrence Bbosa, Aubrey Mainza, Indresan Govender

"Positron Emission Particle Tracking (PEPT) and the Discrete Element Method (DEM) are used to develop a probability based model for the power draw of a tumbling mill. Experiments are conducted using dry spherical glass bead charge in a laboratory scale tumbling mill, which is mounted with a torque transducer and tachometer to measure mill power. Particle tracking information from PEPT is used to reconstruct the motion of glass beads and infer the overall charge behavior, while DEM is employed to simulate particle motion and interaction, with collision mechanics calculated using the Hertz-Mindlin contact model. For both sets of data, the product of torque and average angular velocities in discrete cells are accumulated to obtain mill power. This method is found to be within statistical agreement with measured power for all tests. The information from both techniques is then used to develop a model for the power draw as a function of particle size, mill speed and volumetric filling. Predictions of the model match well with measured and calculated values. The model is found to predict mill power within close agreement with measurement and follows trends consistent with existing work on tumbling mill modelling."

Jan 1, 2014