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By J. Ipinza, J. P. Ibáñez, Casas J., S. Cortés

Copper powder generated during the treatment of electro-metallurgical bleeds by reactive electro- dialysis (RED) had totally reduced the content of ferric ions in acidic synthetic electrolytes (Cu (II)- Fe (III) – H2SO4). In batch and columnar experiments 100% of the ferric ions were reduced to ferrous ions with an extremely high kinetics. A preliminary conceptual design for reducing ferric ions based on an integrate RED- Column for treatment of electro-winning bleed system is discussed. This system is able to recover simultaneously sulfuric acid and copper powder, which will reduce ferric ions. INTRODUCTION It is well known the negative effect of ferric ions in the copper electro-winning process. The increase of ferric content in the electrolyte reduces the current efficiency, i.e., there is an increase in the energy consumption, and changes the surface morphology of the copper deposit (Das, Gopala & Krishna, 1996; Vargas & Parra, 2013). The increase of the specific energy consumption due to the loss of current efficiency occurs by the reduction reaction of ferric to ferrous ions in the cathode, at the anode the ferrous ions are slowly oxidized to ferric ions (Shaw, Dreisinger, Lancaster, Richmond & Tomlinson, 2004). To control the level of iron in the electrolyte, bleeds are needed; this bleed electrolyte containing copper, sulfuric acid, cobalt, iron and other impurities normally is waster, which increased the production cost of the plant (Milbourne, 2002; Mckevitt & Dreisinger, 2009). Then, permanent efforts oriented to treat those bleeds to avoid losses of valuables components are made; among them are use ion exchange resins (Shaw et al., 2004; Mackevitt et al., 2009), chemical precipitation (Izadi, Mohebbi, Amiri & Izadi, 2017) and electrodialysis (Cortés, Ipinza & Ibáñez, 2013). The last one allows to the simultaneous recovery of sulfuric acid and copper powder. If one of the valuables obtained by treating the bleed can be used to reduce ferric ion concentration in the electrolyte could be an important asset. This issue at laboratory scale is reported in this work, the use of copper powder, generated by reactive electro-dialysis when treating synthetic acidic electro-metallurgical bleeds, for reducing ferric ions in acidic electrolytes.

Jan 1, 2019

By C J. Coveney

This paper, after a brief introduction to the mineralization and structure in the mine area, outlines the methods now being employed for grade control at Bethlehem Copper Corporation. Sampling, subgrade drilling, blasting and the actual outlining of the ore are among the topics covered. The paper concludes with a summary of the results obtained, showing a reduction in dilution and an improvement in the grade of the copper ore going to the mill. Introduction T HE Bethlehem property is located in southern British Columbia in the Highland Valley about 30 miles southeast of the town of Ashcroft. The property is located within the Guichon batholith. The rock comprising the batholith is a massive, coarse-textured diorite, which, at Bethlehem, has been intruded by a younger quartz diorite, porphyries and breccia, referred to as the "Younger Complex." Mineralization, consisting of chalcopyrite and bornite with minor pyrite and molybdenite, occurs as disseminations, fracture fillings and coarse blebs. The ore zone lies close to the Guichon -Younger Complex contact where, prior to the development of the breccia, the rocks were shattered and jointed. Subsequent mineral

Jan 1, 1965

By H. Lee

Recently, the effects of global climate changes have become top concerns for governments? decision making regarding infrastructure investments. Extreme weather events that exceed the capacity of existing systems have considerably increased in frequency, and the potential effects of changing trends in temperature and rainfall on infrastructure are difficult to ignore. It is essential for governments to estimate the costs and benefits of adaptation to climate change to properly assess the financial feasibility of infrastructure adaptation strategies. This paper proposes a framework for estimating the economic aspects of infrastructure adaptation to climate change. The framework is composed of three steps of implementation: establishment of alternatives for infrastructure adaptation, performance prediction of infrastructure using future climate scenarios, and asset valuation based on costs and benefits. The first step specifies target assets, their adaptability to climate change, and applicable adaptation technologies. The second step evaluates the effects of climate change on the performance of infrastructure. The last step determines the optimal adaptation strategies among various alternatives based on their net benefits. The framework reasonably incorporates future climate scenarios into the estimation processes for climate change effects and provides a basis for budget allocation for governmental infrastructure investments. The framework is expected to assist government decision makers in establishing adaptation strategies in a rational manner under uncertain future climate change.

Aug 1, 2013

By David S. Robertson

"IntroductionCanada has been one of the world's leading producers of uranium since atomic energy first became of practical importance in 1942. Indeed, prior to this time, between 1933 and 1940, Canada produced significant amounts of pitchblende, as a source of radium, from the Eldorado Mine at Great Bear Lake*.Uranium was first reported in Canada, however, in the middle of the 19th Century in the vicinity of Theano Point on Lake Superior north of Sault Ste. Marie. In the early 1900s, uranium-bearing minerals were reported in Quebec north of the St. Lawrence River and in pegmatites in Quebec and eastern Ontario. In 1930, G.A. LaBine and E.C. St. Paul visited an occurrence of cobalt reported by the Geological Survey of Canada in 1900, and brought the Eldorado Mine into production in 1933, as noted above, producing, in the main, silver and pitchblende.In 1942, developments in atomic energy were such that the Government of Canada, at the behest of Great Britain and the United States, requested that Eldorado, which had been closed in 1940, be re-opened to produce uranium for the Manhattan Project. In September, 1943, all discoveries of radioactive minerals were reserved to the Crown and their staking by private interests was banned. In January, 1944, the government nationalized Eldorado and formed a Crown corporation, the present Eldorado Nuclear Limited, to take over the assets. That year marked the formal beginning of uranium exploration in Canada.The Period 1944 to 1948In 1944, the Crown Corporation and the Geological Survey of Canada began exploring for uranium deposits, largely in the areas of Great Bear Lake and Lake Athabasca. In that year, A. W. Joliffe of the Survey visited properties on the north shore of Lake Athabasca near Beaverlodge Lake and recommended that Eldorado acquire claims in the area. In 1946, P. St. Louis and E. Laurum, prospectors working for Eldorado, found the pitchblende veinlets that led to the Ace Mine. Shaft sinking began in 1951, and production, through a carbonate leach plant, began in 1953.Continuing drilling on the Eldorado claims led to the Verna ore bodies, some 6,000 feet northeast of Ace, on which shaft sinking started in 1954."

Jan 1, 1986

By Gautier Njiekak

The current study provides an experimental approach that aims at documenting the effects of different phases of CO2 (gas, liquid, supercritical fluid) on rock seismic responses. This has implications on obtaining quantitative estimates of fluid saturations for geological storage. The ultrasonic pulse transmission technique is the underlying methodology used in this work. Unlike previous rock physics studies involving CO2 as pore fluid, care is taken to fully saturate the studied samples and also to separate pore fluid effects from pore pressure build-up effects during the experiments. This allows to record seismic effects that are solely reflective of changes in the pore fluid properties. Measurements were done on a CO2 saturated Berea sandstone. Laboratory results show P- and S- waveform variations (velocity, amplitude) in response to CO2's varying phase state. Overall, CO2 phase changes (gas to liquid and gas to supercritical fluid) are marked by a drop in velocities, with the drop being smaller and less immediate over the gas-supercritical fluid transition than over the gas-liquid transition.

Jun 1, 2012

By W. L. Bancroft, Peter Price

"What is now known as the 'Waite section' of the property of Waite Amulet Mines, Limited, was originally the Waite-Ackerman-Montgomery mine. It includes a group of twenty-eight claims lying on either side of the Duprat-Dufresnoy township line, and about 8 miles north-northwest of Noranda, Quebec. ,The original discovery of ore on the property was made by Thomas Montgomery in Block Q, Duprat township, and was staked by him on behalf of himself, I. C. Waite, and C. H. Ackerman, in the summer of 1925. The property was optioned late in 1925 to N. A. Timmins who, after trenching and drilling the deposit, sold his 85 per cent interest to Noranda Mines, Limited. Early in 1927, a company known as Waite-Ackerman-Montgomery Mines, Limited, was formed and shaft sinking and development undertaken. Production commenced in August, 1928, ·and continued tJ May, 1930, when, owing to falling metal prices, shipment of direct smelting ore was stopped. Development of the mine by shaft sinking, drifting, and drilling continued until March, 1932, when owing to the prolonged low price of metals, the property was closed down. In September, 1933, an amalgamation with Amulet Mines, Limited, was effected, the new company being called Waite Amulet Mines, Limited. Early in 1937 operations were resumed, first by direct shipments to the smelter and later by aerial tramway to the Amulet mill. Operations have been continuous up to the present time, reaching an average of 720 tons a day milled for the year 1940. Production during the initial period (1928-1930) amounted to 75,811 tons, having an average grade of 7 .11 per cent copper, 4.47 per cent zinc, and 0.03 oz. gold and 0.65 oz. silver per ton. During the second period (1937 to end of 1946) , 1,060,524 tons, having an average grade of 4.53 per cent copper, 2.97 per cent zinc, and 0.03 oz. gold and 0.65 oz. silver per ton, were produced."

Jan 1, 1954

By John A. Dresser

At a meeting of the Montreal Branch of this Institute in the autumn of 1928, the Honorable J. E. Perrault, Minister of Mines for Quebec, announced his intention to enlarge the Bureau of Mines of Quebec by the addition of a Division of Geology. The announcement further stated that the geological work proposed should be begun in the following field season, and that it should be on a substantial scale of not less than six field parties. The announcement was received with enthusiasm and much encouragement was held out for the success of the effort. It has been thought that the present meeting would be a suitable occasion to present a report of progress of this Division for the three years that have since elapsed. History This, of course, is not the first geological work to be undertaken by the Bureau of Mines. Prior to the establishment of the Division of Geology, the Bureau of Mines had not been unmindful of the need of geological research, but it had always lacked the means necessary to any sustained work. For more than 25 years the late J. Obalski was the Superintendent and the sole occupant of the Bureau. Yet, even then, Obalski, besides routine visits to mining districts, made a few exploratory trips along the north shore of the St. Lawrence river and one to Chibougamau, but without the equipment necessary to effective results.

Jan 1, 1932

By A. M. Bell

"Hallnor mine is in the township of Whitney, Porcupine district. To date, its production of gold has been second largest in the east Porcupine field. Ore was discovered in the property in 1936 by diamond drilling in overburdened country. This drilling was undertaken by Noranda Mines following the discovery of ore in conglomerate at Pamour 1 mile to the east.Milling commenced at the Hallnor in June 1938, and to the end of 1945 432,000 oz. gold had been produced from 889,000 tons of ore, giving an average recovery of 0.49 oz. a ton.The West mine of Pamour, the Broulan orebody, and the veins on the Hallnor and Bonetal are all parts of a mile long vein system that has been separated into three sections by cross faulting. In consequence, they could well have been described in one paper. In treating them individually the viewpoint obtained from each may lead to conflicting opinions, and any conclusions advanced in this paper on the general structure should be modified by the conclusions advanced in papers on the neighbouring properties.GENERAL GEOLOGYRock FormationsThe Hallnor orebodies occur within 400 feet of the contact between lavas and sediments, and may lie in either lavas or sediments. The lavas near the ore consist of flows of pillowed andesite and one flow of more acid and less sheared and chloritized lava locally named trachyte. These flows strike east-west and dip steeply. At the surface on the east side of the property the volcanics have been intensely altered to a massive carbonate rock having a north-south thickness in excess of 1,000 feet . This carbonate body extends west across the property with a plunge of 45° (Fig. 1)."

Jan 1, 1954

"Coupon testing has been used to investigate stress corrosion cracking (SCC) of rockbolts in a laboratory based experimental program. This program has focused on the use of ASTM G39 three- and four-point bent beam coupon specimens, immersed in an acidified sodium chloride test solution containing hydrogen sulfide. The specimens were loaded to a range of stresses from zero, to just above the materials yield strength. It was found that only specimens above an applied stress of 580MPa failed by means of SCC, showing that rockbolts loaded to near their yield strength may be susceptible to SCC in-situ.INTRODUCTIONStress corrosion cracking (SCC) is a failure mechanism that affects material through the growth of hairline cracks when exposed to a corrosive medium while under stress (Jones and Ricker, 1999). SCC has been found to affect rockbolts in the Australian underground coal mining industry and has the capacity to cause the catastrophic failure of ground support systems, potentially leading to falls of ground in underground excavations, injury or death to mine personnel, damage or loss of equipment, and loss of productivity through the loss of roadway access (Crosky et al, 2002).Coupon testing utilises small scale samples that are intended to be indicative of the behaviour exhibited by a material in-situ (ASTM G39). The small scale, and usually high surface area to volume ratio of coupon specimens mean that they corrode at faster rate proportional to their mass, greatly reducing testing times. The small scale of the specimens allows them to be more easily prepared and handled, loaning them to mass manufacturing techniques.A previous study conducted by Vandermaat et al (2012b) into the use of three- and four-point coupon testing in-situ in an underground coal mine failed to result in SCC of the specimens. This paper serves as a follow up laboratory investigation in order to understand why these specimens did not fail. Previous studies into the SCC in rockbolts carried out by Gamboa and Atrens (2003) determined that rockbolt steel has a critical stress threshold of approximately 90% of the material ultimate tensile strength (800-900MPa). This study will focus on this critical stress threshold as a possible explanation for the lack of failure in the in-situ specimens (Vandermaat, 2012b)."

Jan 1, 2015

By DALE MacGREGOR, VERA TUREK

The Blue Mountain nepheline syenite deposit has been the subject of several detailed studies. It has been variously referred to as an intrusive stock, a metasomatic deposit, an intrusive sill and a metamorphic-metasomatic body. The body is divided into six mineralogical zones, the first five being based on the characterizing accessory mineral; muscovite, muscovitemagnetite, biotite-muscovite, biotite, hornblende and pink syenite. Mining currently takes place only in the biotite zone. Foliation is particularly prominent in the central (hornblende) zone and near the margins of the nepheline syenite. Majic bodies within the nepheline syenite may represent basic rocks that have been less altered by metasomatism, metamorphosed basic dykes or sloped blocks of metasediments. The most prominent structural features are the northeast-trending folds that have been modified by later north west-trending folds.

Jan 1, 1984

By C. A. Lorenson

THE Marmoraton mine is located a mile southeast of Marmora, a village in Hastings county, Ontario, 130 miles east from Toronto and 143 miles west of Ottawa. Highway No. 14 from Belleville intersects Highway No. 7 at Marmora and the branch line of the Canadian National railway between Trenton and Bancroft passes through the property just east of the open pit. HISTORY AND GEOLOGY The Marmora orebody appears as the whorls of a thumb print on the aeromagnetic survey map released by the Ontario Department of Min.es early in 1950, the survey of the district having been made in 1948 and 1949, under the joint auspices of the Department of Mines and the Geological Survey of Canada. The 'anomaly' appeared to have interesting possibilities, so Bethlehem representatives carried out a ground survey and began drilling the property in June, 1950. A total of 40 holes, aggregating 37,000 feet, were drilled to delineate the ore-body. The Marmora orebody is a re-placement of Precambrian limesto.ne with zones or bands of magnetite interlaid with metamorpl1ic rocks and cut by later intrusives. The ore and associated Precambrian rocks are overlain by 100 to 150 feet of flat-lying Palaeozoic limestone. It is a low-grade deposit averaging 33 per cent iron and requires concentration to raise it to 65 per cent iron grade.

Jan 1, 1958

By S. Komar Kawatra, Youlian Zhou, Joseph A. Halt

"Bentonite clay has been the most common binder for iron ore pellets. Although bentonite increases pellet strength and durability, it has several disadvantages. For example, its use increases the cost of pellets and decreases pellet purity due to its composition and the higher levels of flux required to meet basicity limits. Several new types of binders have been proposed to replace clay. The binders include starch, modified humic acid (MHA), and dispersants. These binders were used to pelletize a magnetite concentrate from the United States. Typical doses of each binder type were 0.05-0.1 % starch, 0.5-0.75 % MHA, and 0.05 % dispersant. At these doses, the pellets exceeded the minimum recommended values for wet drop, dry compression strength, and fired compression strength. Pellets made with the MHA and dispersants had the lowest abrasion rates of the new binders, and were comparable to pellets made with bentonite clay. In this paper, we compare the new binders, considering pellet quality and the advantages and disadvantages of each binder type.INTRODUCTIONIron ore pelletizers need binders in order to make good quality iron ore pellets. The typical binder is bentonite clay, an alumino-silicate material. Bentonite increases the ballability and strength of iron ore concentrates, but reduces pellet iron grade and reducibility. As high quality bentonites can be expensive to ship, low quality bentonites are often used at significantly higher doses – this reduces iron grade and reducibility even further. Thus, several new types of binders have been proposed to replace bentonite clay.In this paper, we present several new binders for iron ore pellets: starch and modified humic acid (MHA). These have been tested alone and in mixtures with dispersants, or else with bentonite clay. Starch, MHA and their mixtures are briefly described below."

Jan 1, 2016

By S. Spigarelli

The creep response of the AE44 magnesium alloy was studied by means of constant load creep tests carried out at 125 and 150°C, obtaining that at the latter temperature the minimum creep rate observed under an applied stress of 100 MPa was two orders of magnitude lower in the investigated alloy than in AM50. The minimum creep rate dependence on applied stress was described by a conventional power-law, e = Aon , where A was a temperature dependent parameter and n was the stress exponent, resulting in a n value close to 30, i.e. by far larger than those observed in commercial alloys with similar Al content. This large difference in creep response was attributed to the precipitation of rare earths (RE) intermetallic phases distributed in the grain boundary zone in form of an almost continuous network of dispersoids that were observed by means of scanning electron microscopy.

Jan 1, 2006

By A. M. Bell

"The property of Gaspe Copper Mines, Limited, is in the Gaspe Peninsula some 60 miles west of the town of Gaspe and 20 miles in from the north coast. The Copper Mountain deposit was first discovered in 1921 and first optioned and drilled by Noranda in 1938. The Upper Needle Mountain showings a mile south were found in 1938, but it was not until after a delay of 10 years that the more important deep ore at Needle Mountain was located by drilling. Production started in 1955, and the smelter commenced operation in December. Mining is by open stope methods with first production coming from the Lower Needle Mountain orebody, of which only a small portion has been exposed in underground openings.Stratigraphy and AlterationThe country rock is composed of limy siltstones of Devonian age. Away from alteration these are dark and generally carbonaceous. Throughout the drilled area numerous narrow layers of tuffaceous fragmental material occur, and such beds are found to provide excellent horizon markers by virtue of their uniform thickness and wide lateral distribution. These markers are valuable for stope control in mining the bedded replacement deposits.Intruding the sediments at Copper Mountain are porphyry dykes, and one drill hole encountered granite 1,400 feet below the valley. Solutions responsible for the rock alteration and ore deposits seem to have emanated from this intrusive centre.On the mine claims strong hydrothermal alteration has completely obscured the original character of the sediments. The unaltered formations are all very similar in appearance, but following alteration rocks that are very dissimilar in physical characteristics are produced, and such differences have an important influence on ore deposition. The alteration effects are known to extend over a vertical range in excess of 3,000 feet and have a surface area of two square miles. All known ore bodies are within the zone of alteration. In this, rocks are strikingly bleached to a white colour in contrast to the normal dark-coloured sediments, and are much harder and more abrasive, with bedding often obscured. The first effect of alteration is driving off of carbonaceous matter, followed progressively by silicification in the acid rocks and by the formation of lime silicates in the lime rocks, with an accompanying gain in silica and a corresponding loss in lime. Extensive analysis has shown that there is an actual addition of silica involved in the alteration."

Jan 1, 1949

By Hani S. Mitri

Strainbursts in brittle rock are common to deep underground mines. The state of stress at the boundary of mine openings is dictated by a biaxial stress/loading condition. This paper reports the results of a series of biaxial compression tests carried out on 100 mm cubic samples of norite rock, under different horizontal-to-vertical stress ratios. The results indicate that the biaxial compressive strength is considerably higher than the uniaxial one. It is found that the norite sample behaviour under biaxial loading mirrors field behaviour where shearing and progressive spalling of the opening boundary are observed prior to strainbursting. Sample failure is initiated by rock spalling at the sample free faces, i.e. in the plane of biaxial loading. Finally, it?s the out-of-plane shear failure mechanism that causes the sample to collapse. Shear failure takes place violently and abruptly and is accompanied with considerable audible noise.

Apr 1, 2005

By Jr. Wilkinson

Suncor Energy currently mines approximately nine hundred thousand tonnes of ore and waste per day at its open pit operations in the Athabasca Oilsands near Fort McMurray, Alberta. Modeling these deposits for planning purposes is particularly challenging given the characteristics associated with the deposit - stratigraphic deposition coupled with gradational grade distribution. The identification of ore and waste is a combination of bitumen cutoff grade, minimum mining thickness and separable waste thickness subject to criteria established by provincial regulatory agencies. Suncor along with Mincom Inc. have collaborated on this project to derive a methodology, automated by computer software, to streamline the ore and waste identification process. This paper explains the methodology and programs created to identify ore and waste in use at Suncor Energy and how this identification is used to categorize reserves and to generate mine design surfaces.

Apr 1, 2005

By Sandra L. Mesa-Espitia, Gretchen T. Lapidus

Gold present in arsenopyrite matrices is refractory and requires highly oxidative pretreatments in order to obtain acceptable degrees of extraction. However, these release many byproducts that are harmful to the environment. In the present work, a high-grade arsenopyritic ore was pretreated with different solutions, containing hydroxide ion, EDTA, oxalic, tartaric, or citric acids, to improve gold extractions in a posterior leaching step. The pretreatments were carried out at room temperature for 24 hours with a respective ligand concentration of 0.25 M. Once completed, the residue was leached in a thiosulfate solution to quantify the effect of the pretreatment on gold extraction. Only 29% of the gold content was leached, with very slow kinetics, in the untreated mineral. However, after pretreatment with tartaric or citric acid, the kinetics improved, although the percentage of gold extraction only reached 42-45%. The highest gold recovery, with very rapid kinetics, was found with the oxalic acid or the hydroxyl ion pretreatment (70 and 62%), respectively, but also corresponded to the most arsenic co-dissolution.

Jan 1, 2014

By C. Lapointe

"IntroductionTen years ago, when nuclear fission became practical, the element uranium, until then a not very desirable by-.product of the radium industry, became overnight the strategic material par excellence. One of the several important problems that had to be solved at that time was the rapid and precise determination of uranium in ores and concentrates.GeneralThe chemical analysis of uranium ores is a long and difficult business and is complicated by the presence in most ores of a large number of interfering elements. True, much progress has been made, during the past few years, toward simplification of the analytical methods, but the chemical determination still remains the job of a skilled operator. For this reason, the chemical method has been replaced, whenever possible, by a physical determination based on the measurement of the radiations emitted by the elements of the uranium family. There are several types of instruments suitable for these measurements, but of all the radiation detectors known to the physicist, such as ionization chambers, crystal detectors, scintillation, proportional counters, and the like, the Geiger-Mueller counters have proved to be the most satisfactory for routine determinations, because of their simplicity.The Geiger-Mueller counter is a very versatile instrument; it can be constructed to detect any type of radiation, corpuscular -0r electromagnetic. Here, however, we are interested in these counters because of their ability to detect the beta and the gamma radiations, both emitted by some members of the uranium family. The beta radiation is corpuscular, and is composed of fast electrons, while the gamma radiation is electromagnetic."

Jan 1, 1950

By J. P. Nowlan

"This paper is an attempt to outline the structural problems at the Cochenour Willans mine, in so far as their details have been tentatively worked out. It must be emphasized that there are considerable data that can be interpreted in more than one way, and that further work may modify or completely change some of the hypotheses presented herein. Certain features, however, are sufficiently constant to warrant reliance on them when searching for extensions of orebodies.As the individual ore shoots usually have relatively small dimensions, but are often very high grade, structural details are of more than usual significance in laying out a mining programme. An illustration of this is a small shoot recently located and mined as a result of studying a minor slip cutting off a part of high grade gold ore in No. 319 stope. The shoot, which is bounded on three sides by slips, and on the fourth by the original stoping, was roughly triangular in plan, 20 feet on the base, and 40 feet in length. The average width mined was 4.5 feet, but the gold obtained totalled over 1,800 oz.The property lies in Dome township, east of McKenzie island, and consists of an original group of thirteen claims acquired from the Cochenour Willans syndicate, plus one additional group of five claims obtained by purchase from the Kelson Red Lake Gold Mines, Limited, and one other claim that rounds out the southeast corner of the block.The claims of the original group were staked by W. M. Cochenour, Dan Willans, and Horace Young, during 1926 and 1927. The Cochenour Willans Syndicate was formed in 1928, and until incorporation of the present Company work was carried on at varying intervals by several different interests, including Ventures Limited, Hollinger Consolidated, who sank a shaft to open up the 150-foot level, and by the Syndicate itself. The first ore from the property was shipped to the Gold Eagle mill by the present Company in 1939, and amounted to 4,959 tons, from which 2,360 oz. gold was recovered. The first brick was poured in December, 1939, and production has been continuous since that date. To the end of June, 1946, gold having a value of $5,982,000 has been produced from 345,033 tons of ore treated."

Jan 1, 1954

By P. Radziszewski

Industrial practice in mineral processing shows that an important problem in understanding and monitoring in-mill parameters is due to the lack of fundamental knowledge and appropriate sensors. With the development and growing use of DEM charge motion simulators for mill optimisation and design, it is possible to describe the fundamentals of grinding mill behaviour, in improving the understanding of internal grinding mill dynamics and in developing solutions to industrial practice. The main challenge to bringing this DEM technology to the mill operator however was the need for substantial computing power and time. However, what about a simplified DEM charge motion model running in real-time? What about the use of sensor technologies to correct any possible drift in simulator prediction? Could such a technological system be used to predict mill performance and eventually be used for mill control and optimisation? Some of these questions are answered with the development of an "on-line" DEM charge motion simulator package (SAGTools?) along with that of a number of sensor technologies (liner wear, acoustic, instrumented ball) that can contribute to simulator precision. With the objective of bringing this modelling and sensor technology into the concentrator control room to assist operators, this paper aims to describe the main elements of this emerging and developing technology and discuss how it can lead to online mill performance prediction and eventual control.

Jan 1, 2007