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By R. E. de Barrio, M. E. Lanfranchini, R. O. Etcheverry

"The El Abuelo Ca-Fe-magnetite skarn and related hydrothermal quartz veins are located at Cerro Pepita Hill, in southwestern Chubut province of southern Argentina, 1700 km southwest of Buenos Aires. These deposits are developed in a continental magmatic arc environment linked to the Andean orogeny. Iron skarn mineralization is mainly hosted by an Upper Jurassic to Early Cretaceous sedimentary sequence interbedded with Upper Jurassic basaltic andesite, and is spatially associated with Early Cretaceous calc-alkaline dikes. Ore grades vary between 40 and 63 wt.% Fe. In addition, anomalous metal contents (>10 000 ppm Cu and up to 81 g/t Ag) are present in the hydrothermal quartz veins.At least three paragenetic mineral assemblages have been identified in the El Abuelo exoskarn: (1) amphibole > epidote ± chlorite ± quartz, formed by isochemical contact metamorphism; (2) Fe-clinopyroxene ± Ca-garnet, formed during prograde metasomatic anhydrous exoskarn formation; and (3) actinolite ± epidote ± chlorite ± quartz ± magnetite > titanite, resulting from hydrous retrograde alteration of exoskarn. Endoskarn alteration involved an early Mg-Fe-clinopyroxene ± Fe-garnet assemblage followed by retrograde actinolite replacement of pyroxene. Lower temperature hydrothermal alteration related to quartz veins was superimposed on the skarn assemblages, showing an innermost sericite ± adularia ± pyrite ± chalcopyrite assemblage and an external propylitic halo.Some metallogenic characteristics of the mineralization and the geological setting resemble those in several iron oxide copper-gold deposits elsewhere in the world."

Jan 1, 2007

By I. Demers

The abandoned Manitou mine site covers an area of approximately 190 ha near Val d?Or, Quebec. This old site has been generating acid mine drainage for several decades. In 2006, a partnership was established between the Quebec Ministry of Ressources Naturelles (MRN) and Agnico-Eagle Mines to reclaim the Manitou site using tailings from the nearby Goldex mine. These neutral tailings were to be deposited on top of the Manitou site. An extensive study was performed to evaluate specific reclamation scenarios to control acid mine drainage using Goldex tailings as cover material. The article first describes the global approach used for this evaluation, which includes in-situ hydrogeological monitoring, tailings characterization, laboratory column tests, and numerical modelling. Of the thirteen column tests, three were conducted to evaluate the parameters affecting the performance of covers made of Goldex tailings placed over the spillage area of the Manitou site. Geochemical and hydrogeological parameters were assessed during the leaching column tests for almost two years. The tests aimed at evaluating the effect of water table level and monolayer cover thickness on the overall performance. The testing procedure involved monthly leaching and measurement of geochemical parameters. Results indicate that water table position is the most important factor affecting the monolayer cover performance to control AMD. Based on these results, it was established that the water table must be located near the interface between the Goldex and Manitou tailings to effectively reduce AMD generation. Cover thickness also has an impact on cover performance, which is however less significant than the water table position. The testing scenario with a water table located at the interface with a one-meter Goldex tailings cover showed progressive improvement in effluent quality.

Aug 1, 2013

By M. Lahtinen

Traditionally, there have been three main methods for iron removal in the hydrometallurgical production of zinc. These methods are atmospheric precipitation of jarosite or goethite and pressurised precipitation of hematite. Jarosite precipitation is without doubt the leading and the most commonly used technology for iron removal. However, jarosite precipitation has some drawbacks, such as a low iron content (and, thus, high residue volume), high moisture content after filtration and often a high zinc content. These features make any environmentally acceptable way of using or disposing of jarosite more expensive, as compared to hematite and goethite. The importance of environmental regulations has grown in the zinc industry during the last decade, which will have an increasing effect on new investments. Hematite has several advantages over jarosite, such as a high iron content, low moisture and low zinc content. An important advantage of hematite is that it is suited for further use in the cement industry. However, until now the need for autoclave equipment has limited the spread and implementation of hematite precipitation in the zinc industry. Outokumpu Technology Oy has recently developed an alternative method for iron removal, which is the atmospheric precipitation of hematite. A patented method for precipitating hematite at atmospheric pressure is presented and compared with conventional methods for iron removal. The process conditions, the quality of the hematite precipitate and the environmental aspects are also discussed.

Jan 1, 2006

By K. C. Armstrong, A. B. Cron, L. A. Melis

"The Johnny Mountain gold mine in northern British Columbia, owned by skyline Gold Corporation, has been in operation since August 1988. Mill operating difficulties at the start of the operation resulted in a depleted cash flow situation and quick improvements were required to generate a self-sustaining financial basis of operation. In October 1988, Melis Engineering Ltd. was contracted to identify metallurgical difficulties, implement necessary modifications, and undertake mill operations and personnel training in order to achieve production targets.This paper presents the operating difficulties which existed at start-up and describes the methodology used to overcome production problems. Metallurgical testing results are described along with the modifications made to the milling circuit to suit ore metallurgy. Plant changes led to the operation of a simple gravity/flotation circuit to recover gold as bullion and in a copper concentrate. Operation of the originally installed cyanidation circuit was discontinued. This contributed to substantial savings in operating costs and virtually eliminated environmental problems. PROPERRTY LOCATION ANR DESCRIPTIONThe Johnny Mountain mine site is located in northern British Columbia along the Iskuit River about 60 km east of Wrangell, Alaska and 275 km north of Terrace, B. C.. A location map is presented in Figure 1 and a site plan is shown in Figure 2. The complex is located on a mountain plateau about 3, 600 feet above sea level. The plateau is flanked to the north by Johnny Mountain and surrounded on the other sides by steep cliffs."

Jan 1, 1990

By G. F. Warning

"THE H. B. Mine is situated on the north side of Sheep Creek valley, about six miles southeast of Salmo, B.C. It is the most northerly producer along a belt containing a number of zinc-lead deposits, including the Jersey mine of Canadian Exploration Limited, 3 miles to the south, and the Reeves MacDonald mine, 12 miles to the southwest. The important zinc-lead producing area around Metaline Falls, Washington, lies 23 miles to the south. Two prospectors, Horton and Benson, located and staked the oxidized outcrops in 1.907. The property was named the H.B. after the two discoverers. Exploration by a number of operators failed to locate any sulphide orebodies until 1946, when Cominco began a geological study followed by surface drilling which was successful in locating extensive sulphide mineralization. A program of underground exploration revealed sufficient ore to war-rant mill construction. A 1 ,000-ton mill was completed by 1953, but due to low metal prices production was deferred until May, 1955. To September 1, 1959, 1,900,000 tons of zinc-lead ore have been milled; present milling rate is about 1,250 tons per day. Concentrates are trucked to the Trail Smelter, a distance of 35 miles."

Jan 1, 1960

By D. Laguitton

"Mathematics, process theory, process practice and computer applications are the main disciplines that contribute to developing useful techniques for computer simulation of mineral and coal processing plants. As in any multidisciplinary effort, communication or transfer mechanisms must be developed to facilitate the flow of experience between participants of different backgrounds. These mechanisms include written reports, verbal communications, workshops and transfer of computer programs. The SPOC project at CANMET is devoted to computer simulation and as such has addressed, or will address in the near future, problems inherent to methodology transfer. The first major output of the project was the material balance program, MATBAL2, which has been acquired by over 30 organizations. Program documentation, industrial workshops and summer student programs have been used to effect the transfer. This experience is discussed and the future outlined.IntroductionComputer simulation has become a common tool in many different fields of human activity during the past two decades, as illustrated in Figure 1. The total number of articles abstracted in Chemical Abstracts under the general subject entry of “Simulation"" has been following a pseudo-exponential growth since 1972 and was approaching 5000 in 1980, whereas no such entry was even used prior to 1967. This represents over a dozen papers published daily on the subject and should continue to grow to higher figures. Still, progress toward accepting modelling and simulation in mineral and coal processing has been very slow. It will be shown later that this slow acceptance is a cause rather than a consequence of the limited success of the various attempts made so far to draw unambiguous benefits from simulation applications. The real cause of the difficulties in fully accepting the new methodology lies in the multidisciplinary aspect of modelling and simulation, which does not suit the traditionally conservative approach that prevails in designing and operating large and costly processing plants."

Jan 1, 1982

By Steve Cole

"The economic and strategic importance of PGE bearing deposits is fuelling renewed exploration and development efforts in the precious metals mining sector.This paper presents a review of the various techniques used in the processing of PGE bearing ores, from primary benificiation to processing routes for the different flowsheets that have been developed amongst current producers. Recent innovations such as preconcentration of ore using gravity separation, recent trends in flotation circuit design and the development of hydrometallurgical routes for the direct treatment of flotation concentrates without the need for smelting will be discussed. Data from recent projects will be presented to illustrate common characteristics of PGE ores and concentrates.INTRODUCTIONThe six platinum-group elements (PGE): ruthenium, rhodium, palladium, osmium, iridium and platinum, together with gold and silver, are considered to be ""precious"" metals. The recent spike in platinum and palladium prices coupled with the projected increase in demand for the metals has fuelled a spate of exploration and new projects in the PGE sector. Historically primary producers of PGE metals have controlled the flow of information relating to the mining and processing of these ores into the public domain. Very little published information relating to individual operations and processes is available in comparison to the abundant literature relating to other metals.The purpose of this paper is to provide a general overview of the issues relating to the processing of PGE ores. Each topic discussed could easily be the topic of a paper or book and so in many cases only the surface of the topic will be scratched. An attempt has therefore been made to provide as many references as possible.This paper discusses the classification and location of PGE ores, the mineralogical factors that affect recovery of PGE's, methods currently used for recovering PGE's and process trends in PGE metallurgy."

Jan 1, 2002

By Kuwauchi. Y., M. Barati

Recycling of dust using a rotary hearth furnace (RHF) has gained considerable attention in the past two decades for the sustainable production of steel with less environmental impact. In order to further promote the recycling of electric arc furnace dust and carbonaceous wastes using the RHF process, a mathematical model was developed to predict the reaction behaviour of dust-reductant composites. The reduction kinetics of zinc and iron oxides as well as the volatilization behaviour of volatile matter in the reluctant were considered. The modeling approach and some preliminary results are presented in this article.

Jan 1, 2011

By D. Linzey

"History of Whitehorse Copper BeltThe first discovery of copper on the Whitehorse Copper Belt is reported to have been made by miners on their way to the Klondike in 1897. By 1899 the district had been well prospected and many of the presently known deposits had been staked.The first shipment of ore was from the Copper King property in 1900. This consisted of 9 tons of hand picked ore grading 46.4% copper. It was not until the period between 1912 and 1917, the production years of the Pueblo Mine, that significant ore shipments were made. Total production was 140,000 tons at 3.5% copper. An underground disaster killed six men and closed the mine in March 1917.Although the general area was dormant until after World War II, by 1947 geological mapping, magnetic surveys and diamond drilling had been done on the important showings. In 1954 Mr. Aubrey Simmonds directed the formation of Imperial Mines and Metals, which acquired by option and staking a large part of the Whitehorse Copper Belt. In 1957 Mr. Arnold Pitt reorganized the company as New Imperial Mines. With financing from Sumitomo and Toronto-Dominion Bank, a mill was built and production was started from the Little chief orebody by open pit in 1967."

Jan 1, 1977

By Paul R. Clark

Outline of Presentation ? Brief review of gasification and IGCC ? Polygenerationand its potential ? Why gasification today ? Major technology providers and their activities ? US initiatives ? Alberta Energy Resources and application of gasification ? CO2 management ? Advantages and barriers to gasification ? Conclusions

May 1, 2006

By Charles Camsell

Few persons ever stop to consider how vital an influence minerals, and especially metals, have had upon human history, how they have affected the every-day life of the individual or how at different periods they have altered the course of nations and determined their progress. Students and writers of history have dealt very fully with political history and have given us a great deal of detail about the careers and policies of kings, parliaments and nations, but frequently have not touched the economic causes that have been the real forces influencing the development and carrying out of these policies. So far as minerals are concerned there is no single work from which one can get a concise and consecutive account of the growth in the use of minerals, nor of the diverse ways in which the. geographical distribution, the .search for, the development and the use of mineral resources have affected human progress from the beginning of man's history. The reason for this is quite plain, and when one takes a little time to think of it he begins to appreciate the magnitude of the job and he will realize that the story of minerals and mineral resources touches a tremendous range of human activity, not only of mining .and metallurgy, but the whole field of agricultural and industrial growth, of exploration and colonization, transportation and commerce, monetary system, commercial policy, in short, almost every phase of economic life.

Jan 1, 1926

By George R. White

"The Phalen Colliery, the Cape Breton Development Corporation's flagship, is now producing thermal and metallurgical grade coal in Eastern Canada's Sydney Coal Field. The colliery is a drift mine operating under the waters of the Atlantic Ocean. Improved mechanization, including a 2200 tonne per hour cable conveyor, and the introduction of modern retreat longwall mining methods as part of the Phalen concept are now paying off in better productivity and low operating costs. Geological conditions within the coal field are consistent with plans for ever greater outputs in the 1990s. Although much of the current production improvement is related to uprated machine capacity and simplified mines planning there is potential for even further development in the areas of maintenance, process control and engineering. Human resource development will also be a key factor. These programs are now well under way and Phalen Colliery is poised for top results in the 1990s. Comparison of the CBDC's top producer with similar operations elsewhere in the world, quantifies that potential.IntroductionAn exciting new mining project which has recently started production on Canada's East Coast has been conceived and designed to be one of the most modern and productive coal mining operations in North America.As with all mining operations, the business is basically that of material transportation. Daily, the product is transported many kilometres from the underground face to the surface and then to washing facilities. Men, materials and equipment are transported to and from the surface and the operating faces and services, such as electrical power, ventilating air, fresh water, discharge water, communications and compressed air are supplied throughout the operation to cover operating requirements. On all accounts the operation has been designed to take advantage of the latest proven technology."

Jan 1, 1990

By Laxman M. Amaratunga

"The fine fraction of tailings is usually excluded from the backfill process and generally disposed on the surface in tailings ponds. Because of the ever increasing demand for fine grinding in the extraction process for improved liberation of valuables in the ore, increased production of fines in the tailings has resulted. The negative impact of surface impoundment of tailings on the environment is well known. Amaratunga and Annor (1989) first presented a concept of fine tailings agglomeration for backfill.This paper presents the development of the novel cold-bond tailings agglomeration (CBTA) technology for non-reactive fine gold mill tailings. For cold-bond agglomeration regular portland cement was used as a binder. In order to cut costs, alternate binders such as lime, and blast furnace slag cement were examined. The effects of binder dosage, curing time, and agglomerate size on the fracture load strength of the agglomerate were studied.Fine tailings agglomerates are mixed with coarse tailings or non-agglomerated fine tailings to make high density fill compositions to be used as underground backfill. Alternatively, the agglomerates can be used as aggregates for surface applications. The paper discusses the environmental and operational benefits of this total tailings utilization and disposal technology.IntroductionIn Canadian mines, mill tailings are probably the most commonly used material for backfill. However, only the coarse fraction of tailings is desirable for use as hydraulic fill or high density fills. The fines are disposed on the surface in tailings ponds since they are unsuitable for underground backfilling owing to the following factors:i) slow settling ratesii) longer percolation timeiii) excessive consumption of binder due to drainageiv) poor compactionFor improved value liberation more milling operations have resolved to fine grinding in their comminution circuits. Gold milling operations driven by down stream leaching processes grind their ores excessively fine. In general, gold mines use hardly any tailings for backfilling. This can result in periodic short falls and the need to search for alternate backfill material from other sources. Apparently, the gold producers are the most identifiable sector which suffer from a shortage of backfill materials ( Amaratunga and Annor, 1989)."

Jan 1, 1994

By M. O. Makwarela, M. W. Erwee, K. Bisaka

"Energy efficiency in mining and minerals processing forms part of Mintek’s long-term research strategy which includes a specific programme designed at overcoming the challenges faced by the South African pyrometallurgy industry.The electric smelting industry is currently severely constrained by the global economic downturn as well as by the availability and increasing cost of electricity. Efficient utilisation of electricity through energy recovery systems and improved smelting process flowsheets can significantly contribute towards creating sustainable operations.Apart from efficient engineering design and solid process control, smelting of either cold or hot pre-reduced ores has been shown to decrease furnace electricity consumption by more than 40%. Various methods of solid-state reduction tests have been carried out at Mintek in order to select the most appropriate process option in the context of the South African industry. This paper summarises a subset of the results obtained, specifically on pre-reduction tests done on South African chromite and manganese ore pellets.In this set of tests, it was found that the use of an organic binder, together with B2O3 as flux, promotes manganese ore pre-reduction, but retards the pre-reduction of chromite. By pre-reducing the manganese ore feed, significant cost savings can be achieved in subsequent smelting processes and there is potential to minimise manganese losses as a result of fuming, due to possible lower operating temperatures."

Jan 1, 2016

By K. Hambrice, E. Fauveau

"When it comes to measuring the level of bulk solids, liquids, and everything in between, guided-wave radar technology now offers more level-detection capabilities than ever before. For an ever-widening range of previously hard-tomeasure products such as molten sulphur, liquid ammonia and petrochemicals, guided-wave radar transmitters provide accurate level measurements even under harsh chemical environments, wide variations in operating temperatures and pressures, and low dielectric constants.Great strides have been achieved in making these units easier to configure to a variety of process applications coupled with the simplicity of integrating these devices with most digital communication protocols. These improvements come as welcome relief to process engineers within an expanded range of level applications across several different industries that seek solutions to measuring the contents of tanks, silos, hoppers, bins, mixing basins, and vessels.Because radar transmitters have no moving parts, radar has already established a dominant niche in level measuring that quickly distances itself from mechanical means, which do not hold up as well in dirty service. Radar achieves its nonmechanical level detection capability by measuring the time of flight of the transmitted signal.Known more accurately as time domain reflectometry (TDR), the process involves sending microwave energy down into a vessel. When the pulse of radar energy reaches the product (indicated by a change in impedance), part of the pulse is reflected back toward the transmitter.A receiver measures the exact duration of time between the transmitted and reflected signal — the “time of flight.” The device analyzes this time and ultimately displays the level of the product as a distance in feet, metres, or other engineering units."

Jan 1, 2003

By J. A. Morgan, P. M. Dimmell

Abstract - The Aubry pegmatites are located on the Seymour Lake property, 15 km north of Lake Nipigon in northwestern Ontario. The property lies within the Caribou Lake-Marshall Lake greenstone belt along the English River-Wabigoon subprovince boundary of the Superior province of the Canadian Shield. The property was optioned in March 2001 by Linear Resources (now Linear Gold Corp.), who carried out gridding, prospecting, geological mapping, soil and lithogeochemical sampling, trenching, channel sampling, and a total of 1,866 m of diamond drilling in 32 holes. The Aubry pegmatites are classified by Breaks et al. (2003) as complex type, spodumene-subtype, lithium-cesium-tantalum pegmatites (Cerný, 1989). These pegmatites generally form under high-pressure-low-temperature conditions, display complex internal zoning, have relatively low Nb/Ta ratios in the ore-forming assemblages, and contain significantly elevated tantalum values (Cerný, 1989). Other examples of spodumene-subtype pegmatites include the formerly producing Hugo pegmatite in South Dakota, and the currently producing Greenbushes pegmatite in Australia. The Aubry pegmatites occur as an undulating system of stacked sheets that dip moderately to steeply eastward over a 1-km strike length. The main portion of the North Aubry pegmatite ranges in true thickness from 10 to 28 m over a strike length of 125 m, whereas the thickest portion of the South Aubry has an estimated true thickness of 15 to 16 m over a minimum strike length of 95 m. The North Aubry pegmatite remains open downdip and along strike to the north, whereas the South Aubry pegmatite remains open downdip and along strike in both directions. The Aubry pegmatites are among the most highly evolved in Ontario, with the southern end of the North Aubry (trench 5/6 area) being the most highly fractionated (Breaks et al., 2002). Channel samples from the trench NA-5 area of the North Aubry pegmatite produced values up to 2.49 wt.% Ta2O5 over 4 m. Coarse manganotantalite crystals, up to 5 cm in diameter, from this trench contain up to 84.9 wt.% Ta2O5 (Breaks et al., 2002). Drill hole SL02-31 in the trench NA-6 area gave values of 0.046 wt.% Ta2O5 over 17.7 m, including 1 m @ 0.464 wt.% Ta2O5. Further exploration will focus on defining the grade of the North Aubry zone, extending and defining both known pegmatites, and identifying additional Ta-rich zones within them. Lithogeochemical and enzyme leach soil geochemical data suggest the presence of multiple undiscovered pegmatites on the property.

Jan 1, 2005

By Ralph V. Stewart

"The asbestos orebody is contained within ultrabasic rocks of Precambrian age, being located in the continuous permafrost zone of the Quebec Ungava Peninsula, some 300 miles north of the tree line at approximate latitude 61'49' and longitude 73°58'.The asbestos deposit is at the western tip of a folded ultrabasic sill complex which trends northeast and covers an elliptical area 4.5 miles wide by 15 miles long. Locally. the asbestos occurs in. a completely serpentinized dunite rock. The principal rock types in the vicinity of the ore-body originally consisted of dunite, peridotite and pyroxenite, all of which have experienced at least two periods of alteration, so that no fresh rock now remains.The main ore zone in the open pit is approximately one quarter mile in length, 150 to 200 feet in width, and plunges at 25 to 30 degrees in a northeast direction below surface, to a vertical depth of at least 1,200 feet, Consider¬able tectonic activity resulted in favourable structural conditions which culminated in the formation of the ore zone in its present form.The deposit consists principally of cross-fibre ""gash type"" veins which vary in length from several inches to several feet. The principal fibre vein direction is parallel to the dip of the enclosing serpentinized dunite and sill complex.Some of the problems encountered during diamond drill¬ing in permafrost are briefly discussed."

Jan 1, 1976

By Y. Thibault, G. Deschênes

An open-pit mine, located in Mexico, processes an ore a rate of 4000 tpd, using conventional cyanidation and AYR. A laboratory study was conducted to increase silver extraction and to reduce the concentration of cyanide in leaching. The sample contained 0.41 g/t Au, 125 g/t Ag, 99% gangue minerals, 0.7% pyrite, 0.07% sphalerite, 0.03% chalcocite. Silver was present as acanthite, stromeyerite, silver mercury/halogen, silver with copper in solid solution and jalpaite. The plant conditions (2400 ppm NaCN) produced 90.2% gold extraction (residue at 0.04 g/t Au) and 92.7% silver extraction (leach residue at 9.1 g/t Ag). The CELP (CANMET Enhanced Leaching Process) produced 97.0% silver extraction (residue at 3.8 g/t) and 90.2% gold extraction using 500 ppm NaCN. The incremental gross revenue was estimated at $US7.6 million and the reduction of cyanide costs was $2.9 million per year (79%).

Jan 1, 2011

By M. Fafard, M. Dupuis, P. Goulet, J. Bédard

Start-up of a Hall-Heroult cell is a delicate task that can affect pot performance and pot life. Modem practices for high amperage cells involve preheating the lining before the molten electrolyte is poured in. Different preheating methods and heat-up schedules are used throughout the industry, and the optimum between a short start-up and damage minimization to the cell is elusive. Direct electrical coke-bed preheating is one of the most common techniques. This practice typically results in a non-uniform surface temperature distribution and can generate detrimental thermal gradients in the cathode blocks. Numerical modeling is an invaluable tool to study this complex problem and can help improve the preheating procedures. The modeling of the mechanical response of the lining is critical to detect risks of cathode block cracking or the development of gaps where liquids could leak into. Taking into account the baking of ramming paste, the quasi-brittle nature of carbon and the contact interfaces between different materials are examples of key elements to consider. A finite element slice model of a cell was built and simulations of different electrical preheating scenarios were performed using the inhouse code FESh++ to demonstrate what can be learned through thermo-chemomechanical modeling. The potential industrial application of the model is discussed.

Jan 1, 2006

By Nirmal Weerasekara, Lian X. Liu, The University of Queensland, Weiguo Xie, Benjamin Bonfils, Ping Yu

A mill model structure based on the population mass balance framework incorporating breakage characteristics, slurry and solids transport, product classification and discharge and energy consumption was reported in XXVII IMPC and named the Generic Tumbling Mill Model Structure Version I (GTMMS I). In this work, a new 4D (four dimensional) appearance function sub-model based on the experimental results of the JK Rotary Breakage Tester (JK RBT) was developed to describe the breakage characteristics and was applied to this new model structure. The newly developed 4D appearance function model has fewer fitting parameters and is more generic in nature. Most importantly, it is applicable to both high and low energy impact breakage. It is therefore much more versatile in comparison to the existing JKMRC t10- tn appearance function and the size-dependent JK M-p-q t10-tn appearance function. In addition, the Discrete Element Method (DEM) energy distribution model was integrated into the new model structure. With DEM results providing energy distribution information inside the mill directly, the selection function and the back-calculation method used in the existing JKSimMet modelling method are not needed in this model structure. With the above two revolutionary innovations, the previous model structure was upgraded to the Generic Tumbling Mill Model Structure Version II (GTMMS II). Furthermore, the new model structure is dynamic in nature with time-stepping technique for non-steady-state simulation. A case of the dynamic grinding of a SAG mill was studied to validate the GTMMS II. The model simulation results agreed well with the plant data. With the newly developed 4D appearance function model, the incorporation of DEM energy distribution and transport function, the GTMMS II is an important step forward towards mechanistic modelling of tumbling mills.

Jan 1, 2016