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By W. D. Robson

THE prevention of silicosis by metallic aluminium has been reported by Denny, Robson, and Irwin in two papers. The first (1) was published in 1937; the second (2), in 1939. The results definitely established that silicosis was prevented in animals by the inhalation of small quantities of aluminium. The present communication records subsequent progress in this field of research. HARMLESSNESS OF ALUMINIUM Animal experiments having served their purpose, it became necessary to consider means to test the discovery on humans. A question for immediate consideration was: Is aluminium harmful to man when inhaled as a fine powder? While the animal experiments were reassuring, since they conclusively showed the powder to be innocuous when breathed by animals, it was, nevertheless, desirable to have additional reassurance with regard to its effect upon human beings. Through the courtesy of the Aluminum Company of America and especially the valued interest in this problem displayed by that Company's Director of Research, Dr. Francis C. Frary, a study was made of the records pertaining to the health of a group of 125 employees who had for many years been engaged in the manufacture of finely powdered, metallic aluminium for the paint and ink industries. The conditions were such that these employees had inhaled varying and oft-times very dense concentrations of this powder daily over periods ranging from 6 to 23 years, the average for the group being 12 years. X-ray pictures of their chests showed no abnormalities attributable to aluminium. Their general health seemed better than that of the 3,000 workers in other sections of the plant. In fact, the early films of three employees in this group of 125 showed shadows suggestive of minimal tuberculosis, which shadows were not discernible in films taken after considerable periods of exposure to aluminium powder. The harmlessness of aluminium was, by this study, reasonably well established at the outset, a finding subsequently verified by Ontario research on humans.

Jan 1, 1944

By B. W. Williams

The crack propagation behaviour of Zr-2.5Nb pressure tube material was studied through comparison of the measured behaviour with the predicted response from finite element analysis. Three-dimensional finite element simulations of compact tension specimens were performed using the crack tip opening angle as a fracture criterion to allow for crack propagation. To obtain reasonable agreement with the measured behaviour, it was important to capture both the anisotropic plastic deformation behaviour of the Zr-2.5Nb material through use of the Hill-48 yield criterion and damage due to void growth, nucleation, and coalescence through the use of a Gurson-based constitutive model in the simulations.

Jan 1, 2010

By Fathi Habashi

"Crushing and grinding of ores and their beneficiation by washing away gangue minerals has been practiced since ancient times. Primitive crushing was done by hand pounding the ore with a hard stone then by using metallic hammers. The mortar and pestle was mechanized using a lever and when the size of operations increased in the middle ages, the stamp mill was introduced. The grindstone played an important role in grinding of ores. Panning for gold and hand sorting of minerals were two old methods of separation, now gave way to modern techniques. Flotation started in the middle of the nineteenth century by using oils to collect the mineral particles and float them on the surface of the aqueous slurry. It was only in the 1920s when it was discovered that organic compounds were affective floating agents. Textbooks written by distinguished engineers such as Rittinger, Rickard, Pryor, Taggart, Richards, Gaudin, and others contributed to the recognition of this field as a new discipline to be taught in Universities. INTRODUCTIONThe ancient Egyptians knew already that it would be easier to melt an earth rich in gold particles than another which is poor. As a result all efforts were made to enrich the gold by washing away the light gangue minerals (Figure 1). Another ancient method for enriching gold particles from a river stream was by means of fleece, hence the Greek myth of the “golden fleece”. The present day Georgia was known in ancient times as Colchis and was a center for gold working. It was known to the ancient Greek as the land of Golden Fleece. The use of special cloth to catch gold particles was also described by Agricola in his 1555 book De Re Metallica (Figure 2)."

Jan 1, 2009

By P. Dyas, H. Zouitt, D. M. Smith

"Falconbridge Copper's Lac Shortt gold mine is located in northern Quebec approximately 300 km northeast of Val D'Or and 100 km west of Chibougamau (Pig. 1). Engineering for the mill commenced in early 1983 with a feasibility study. The plant was commissioned in the fall of 1984 at a capital cost of approximately $12 million. Design capacity was 750 tpd which was increased in the fall of 1985 to the current level of 1200 tpd.The ore at Lac Shortt is free milling, grading an average of 5.5 g/t gold which is finely disseminated throughout the host rock. Pyrite at 3 to 5% by volume and traces of copper mineralization are also present.Some of the latest gold processing techniques known at the time of design were incorporated into the mill. These include carbon-in-pulp, pressure stripping, electrowinning of pregnant solution and induction furnace refining. The plant also features several innovations such as a unique interstage carbon retention screen in the CIP circuit and the outdoor location of the cyanidation feed thickener, mill solution tank and reagent storage silos despite -40° Celsius winter temperatures.This paper describes the current mill process and discusses some of the problems encountered during the first two years of the plant's operation. CRUSHINGThe Lac Shortt surface crushing facilities are located in a separate building, isolated from the wet processing circuits for dust and noise control reasons. The crushing plant equipment was originally utilized at the Manibridge operation in northern Manitoba where it had been designed to operate at 135 tph. However, at Lac Shortt a rate of only 80 tph has been achievable to date, mainly due to the hardness and frequently slabby breakage characteristics of the ore. Therefore, in order to meet fine ore requirements at the current mill throughput of 1200 tpd, the crushing circuit is run seven days a week. 24 hours a day. Availability has been averaging 65%."

Jan 1, 1987

By R. W. Watson, H. D. Peer

"This paper outlines the history of steel linings in the Autogenous Mills, the factors influencing the decision to convert to rubber lining, and the operating and cost experience with the rubber liners to date. INTRODUCTIONSherman Mine is an open pit iron ore mining, concentrating and pelletizing operation located at Temagami, Ontario. The operation employs 392 hourly employees and 81 salaried employees and has an annual capacity of over one million L.T. of high quality iron ore pellets produced from low-grade magnetite ore.The Sherman Mine is a joint venture; 90% owned by Dominion Foundries and Steel Limited (Dofasco) of Hamilton, Ontario, and 10% owned by the Tetapaga Mining Company, a wholly-owned subsidiary of the Cleveland Cliffs Iron Company of Cleveland, Ohio. The operation and management of the mine is by Cliffs of Canada, Limited. Development of the property was started in 1965, with pellet plant production beginning on March 17, 1968. At the present time, the orebodies contain sufficient reserves to sustain operations at current production levels for 30 years. Mining was originally carried out in three orebodies, the North, South, and West pits. The North Pit has been exhausted and mining operations ceased in the spring of 1980. A fourth pit, the East Pit, will be developed during the early 1980's."

Jan 1, 1981

"INTRODUCTIONThe Kidd Creek Concentrator is located 28 kilometers east of the city of Timmins, Ontario. Two types of ore are treated; 'A' type, a copper-zinc-low silver ore producing copper and zinc concentrates, and 'C' type, a copper-lead-zinc-high silver ore producing copper, lead and zinc concentrates.The ore is processed at a combined rate of 12,400 metric tonnes per day through four parallel grinding and flotation divisions. Three divisions treat the 'A' type ore and the fourth treats the 'C' ore. Each division is fed from its own fine ore bin.This paper reviews the grinding section with specific emphasis on grinding media consumption and the factors affecting it as related to 'A' type ore. At Kidd Creek there was an awareness that grinding media consumption varied on a weekly and monthly basis. The reasons for this variation was usually attributed to ore hardness as evidenced by short term variations in the circuit feedrate and head assays. However, there has been a diversity of opinion published in recent years regarding the factors contributing to steel consumption. This initiated a study of historical Kidd Creek operating data, from the period 1970 to 1986 inclusive, to determine the effect of various operating parameters on media consumption. The results of the study could then be used as a baseline for future media consumption testwork."

Jan 1, 1988

By J. Andrew Cornier, Mike Cooper

"Upon successful completion of the AG/SAG Mill project (Cooper et al., 2001) the Brunswick Mine concentrator was configured with single line processing through the AG/SAG mill, followed by two parallel ball mill and flotation circuits. The Stage Grinding project was undertaken to utilize a pre-flotation stage on the AG/SAG mill primary cyclone overflow and simplify the flowsheet by consolidating the two ball mill and flotation circuits, resulting in single line processing fi-om AG/SAG mill to final concentrate. Concurrently, the reclaim water supply capacity was increased to enable flotation cleaning at lower percent solids.Benefits from the Stage Grinding project include revenue enhancement from increased zinc grade and recovery combined with additional lead recovery. Further benefits included a reduction in the number of process pumps, reduction in loss associated with spillage to sumps and process simplification through efficient use of equipment layout.The Stage Grinding project was implemented in six phases over a period of seven months in 2000. Each phase was commissioned during scheduled concentrator shopdays with minimal additional downtime required. One year after project approval the Stage Grinding project was completed at a total cost of $1 1.8 million.INTRODUCTIONThe Noranda Inc. Brunswick Mine, located near Bathurst, New Brunswick, is one of the world’s largest leadzinc mines. Milling of ore began in 1964 from the No. 12 orebody, with an expansion in 1966 to accommodate ore fkom the No. 6 open pit located several kilometers away. In 1980 the pit was exhausted and the concentrator rationalized to accept a design feed rate of 10,500 tomes per day from the No. 12 mine. In excess of 100 million tomes have been milled to date, representing over three-quarters of the known reserve. The concentrator employs differential froth flotation to produce lead, zinc, copper and leauzinc bulk concentrates. The ore is massive sulphide, with approximately 20% valuable minerals, 60% pyrite and 20% silicates."

Jan 1, 2002

By J. Desrosiers

"Minnova Inc. has five operating divisions thoughout Canada. One of them is Lac Dufault which was established in 1964.Lac Dufault is located 15 km north of Rouyn-Noranda, in what is known as Noranda volcanic centre, in northwestern Quebec. For more than 25 years, Lac Dufault has produced copper, zinc, gold and silver from four different mines: Norbec, Millenbach, Corbet and now Ansil.Ansil, officially in production since July 1989, is one of the deepest mines presently in production in Quebec. This high-grade copper, gold, zinc and silver orebody is being mined at a rate of 1200 tonnes per day with a total workforce of 200 employees.Of particular interest are the high mechanization level of the underground mine, technical innovations also underground, and computer applications throughout the division.IntroductionMinnova Inc. was formerly known as Corporation Falconbridge Copper until 50% of its shares were bought by Kerr Addison Mines Ltd . in 1986 and it became a member of Noranda Group of Companies.Minnova stands for mining innovation. It means Minnovaaims to use state-of-the-art technologies in mining and exploration to achieve maximum efficiency and cost effectiveness. It also means that they aim to use both proven and innovative management principles to the optimum benefit of their employees and shareholders. Minnova has operations across Canada. Presently four mining divisions produce copper, zinc, gold, silver and lead. Two are situated in Quebec: Lac Dufault (established in 1964) and Lac Shortt (established in 1985); one in Ontario; Winston Lake (established in 1988); and one in British Columbia; Samatosum (established in 1989).Minnova has an annual exploration budget of $15 million divided 60/40 between base metals and precious metals. Most of Minnova's exploration efforts are concentrated around their existing mines. Exploration is carried out from six regional offices located at Rouyn-Noranda and Chapais in Quebec; Thunder Bay in Ontario, Vancouver in British Columbia, Reno, Nevada in the United State and Panama City Panama. Each of the Canadian offices maintains close liaison with nearby operations.Lac Dufault Division is located in the Noranda mining camp, approximately 15 km north of the city of Rouyn-Noranda, in northwestern Quebec (Fig . 1)."

Jan 1, 1991

By M. Pearson, W. Bristowe, A. Hanson

"There's no such thing as quality assurance; only quality control ... by inspection. "(1) A common misunderstanding in the procurement and construction of custom designed, fabricated pressure vessels and piping systems is that quality assurance can be achieved by simply referencing codes, standards, ISO 9002, QMS or other such programs in the contract documents. In the authors' experience, nothing could be further from the truth, not detrimental to the performance of the equipment than the exclusion of inspection activities and reliance upon warranties and "fit-for-purpose" clauses. Likewise, the expectation that fabricators, suppliers, or third party inspectors can provide such assurances is also unrealistic where they have limited knowledge of the process, material selection criteria, or limited technical resources. The development and successful execution of a quality assurance program is a collaborative effort by engineers, designers, material suppliers, equipment fabricators, and field inspectors with the full understanding and support of the end user.This paper presents an outline of the quality control activities undertaken by the authors for several recently completed and on-going hydrometallurgical projects. The activities include: prequalification of fabricators and sub-vendors, shop audits, material validation testing, material source control and verification, positive material identification of weld metal overlay, specialised welding inspection, contamination control for titanium and titanium-clad fabrication, eddy current and mass spectrometer (helium) leak testing of shell-and-tube heat exchangers, hot cycle testing of titanium clad equipment, tolerance verification for refractory lined equipment, final inspection and cleaning.

Jan 1, 2004

By Réjean Lévesque

SIDBEC-NORMINES a été incorporée en 1976. Depuis la fin de 1977, ses activités comprennent outre la concentration au lac Jeannine, près de Gagnon, du minerai de fer extrait du gisement du lac Fire, I'exploitation d'un atelier d 'enrichissement secondaire et une usine de bouletage à Port Cartier. L 'objectif principal de SIDBEC-NORMINES est de produire six millions de tonnes de boulettes d'oxyde de fer par année, dont trois millions auront une faible teneur en silice afin de répondre aux exigences de la réduction directe. Les installations de SIDBEC-NORMINES sont adjacentes aux installations portuaires de la Compagnie Minière Québec Cartier, à l'est de la ville de Port-Cartier. L 'ensemble est conçu pour produire les deux types de boulettes avec deux circuits d'agglomération installes en parallèle. La production de concentré enrichi (68% Fe et plus) est obtenue dans une usine d'enrichissement utilisant le precédé de séparation magnétique hum ide ahaute intensite (separateurs Jones). À l'usine de bouletage proprement dite, on effectue Ie broyage du concentré et sa mise en boulettes sur disques; l'in duration des deux types de boulettes est obtenue sur deux chaînes d'agglomération Dravo dont chacune a une capacité annuelle nominale de trois millions de tonnes.

Jan 1, 1979

By K. L. Murphy, G. Multamaki, P. M. Huck

"A preliminary evaluation, based on existing data, has been made of the implications of placing radium-barium sludge in tailings areas. The study was restricted to a consideration of possible increases in the quantities of radionuclides escaping to the environment through either groundwater or surf ace water, considering the types of tailings treated and the effluent treatment systems currently operating in Canada.IntroductionIn the recovery of uranium from ore deposits, the tailings produced by mine/mill complexes are conveyed to impoundment areas in slurry form. After settling, the supernatant is discharged to the environment together with runoff from precipitation on the tailings bas in. Currently, all operating uranium mines in Canada employ barium chloride treatment to control the release of dissolved radium to the aquatic environment. The dissolved radium in the tailings decant is precipitated with barium chloride, forming (Ra,Ba)SO4, and allowed to settle in ponds or lakes. In some instances, settling tanks have replaced ponds and flocculants have been added to aid settling. Because the Atomic Energy Control Board does not consider the precipitation ponds to be suitable for final disposal of these sludges, acceptable sites must be found. Options which have been suggested for sludge management include underground placement either in worked-out mine areas or in special chambers, or placement in the tailings areas. Conceptually, the latter alternative is attractive and probably would minimize sludge handling. This alternative would be subject to the AECB policy which requires that upon abandonment, radioactive releases from a tailings area must be within present regulatory limits and that treatment to meet these limits should not be required in perpetuity.No quantitative data exist concerning either the effect of physical and chemical conditions in the tailings on resolubilization of radium from precipitated sludges or the fraction of this additional radium which would be released."

Jan 1, 1982

By M. A. Creaney

"The Construction Group is responsible for the construction of all of Placer Dome’s major projects and contributes to the development of most major feasibility studies. This group includes an international collection of Placer Dome people who have built mines in Papua New Guinea, Australia, Chile, the United States and Canada. This paper outlines the changing role of the Construction Group from the early days of single projects to today, when several projects are in various phases from feasibility to construction. The projects’ total annual budgets have from time to time exceeded one billion dollars. IntroductionAs the competition increases globally between the major gold mining companies, the impetus continues to build mines at the lowest cost with the shortest construction schedule. Placer Dome has more than met that challenge by building mines around the world at a pace that was not contemplated 15 or 20 years ago. Since 1960, Placer Dome has built 30 mines and expansions at a cost of nearly 4.5 billion dollars.In the last six years alone, Placer Dome has built 14 mines and expansions, worth 2.6 billion dollars. The company’s success is due primarily to Experience, Innovation, People and Standards.The diversity between projects, let alone the pace, has been a challenge. Placer Dome has built mines around the world in a variety of extreme climates and distinctive cultures. The construction experience gained from these projects has allowed Placer Dome to develop an extensive knowledge and data base making it easier to “fast track” projects.Through the years Placer Dome has developed a human resource base. It now has an experienced and adaptable core team of people able to set up construction projects and build mines anywhere in the world. By developing standards and systems to support the projects they can act as soon as a new project is approved, and complete the projects quickly and effectively. The result is that Placer Dome now has the construction expertise to build its own mines, giving them the competitive advantage that allows them to design and construct a mine in the least time at the lowest capital cost. This was demonstrated in March 1997 with the completion of the construction of two new mines in 12 months."

Jan 1, 1998

By Ron Board

"Probably the only thing that can he said about conveyor belt scales without fear of contradiction is that they have been responsible for as much or more puzzlement, argument and frustration than almost any other piece of equipment commonly found in ore processing facilities. To be sure, there are certainly a good number of satisfactory installations, some of these having been achieved through forethought and careful consideration in the early stages of plant design, while others seem to owl their success to what seems to be little more than good luck or white witchcraft; and it might also appear that black witchcraft or other gremlins are solely responsible for the poor performance of many belt scales that enjoy well-designed installations with apparently good operating conditions.This paper is intended to acquaint users with the major operational reasons why belt scales seem so fickle (and downright ornery too), and establish some reasonably simple test standards against which the performance of scale hardware can be measured. Then it shall be shown how the design flexibility of electronic scale systems can offer particular advantages in overcoming some of these everyday problems in a practical way, and without undue inconvenience to plant operations."

Jan 1, 1975

By H. C. Counsell, R. Webber

"The mill at Denison Mines' Elliot Lake Operations started up in 1957, with a capacity of 6,000 tons per day. Over the years various plant modifications expanded th.is to 7 500 tons per day. In 1976, management decided to carry out a major expansion of the milling capacity, and during 1980 the grinding capacity was increased to 15,000 tons per day.The original comminution system consisted of a conventional crushing plant feeding minus S/s-inch material to rod and pebble mills, in closed circuit with mechanical classifiers. The key decision that had to be made was whether the expansion should include conventional or autogenous grinding flow sheets.During 1977, extensive pilot plant studies at Lakefield Research showed that two-stage semi-autogenous grinding, with some steel media in the primary mill and with pebble media in the second stage, produced stable grinding conditions. This type of circuit was selected by Denison for the expansion, and went into production in 1980. Primary millThe flow sheet of the semi-autogenous grinding circuit is shown in Figure 1. The primary grinding mill is a Koppers 28 foot by 10 foot mill, driven by a 4,000 h.p. synchronous motor. It is fed with a minus 8-inch run-of-mine ore, and 4-inch grinding balls are added as supplementary grinding media. There are two Koppers 15.5 foot by 22 foot secondary pebble mills, driven with 1500 h.p. synchronous motors. Each grinding stage operates in closed circuit with cyclones, and the primary cyclone overflow is the feed to the secondary mills. The circulating load in the primary stage can be controlled by adjusting the cyclone apexes."

Jan 1, 1984

By H. Thomasson

THE war, like all destructive agencies, has focused attention on salvage and conservation, and to such an extent that a decade of normal progress has been crowded into a few months. This is particularly true as regards the repair of cutting tools. As a consequence, there has arisen a wide demand for comparable data by those engaged in such work, and for basic information by others who wish to repair tools. These repairs may be grouped in three classes: (1) The repair of broken tools of relatively slender cross-section, such as broaches, reamers, drills, etc., of a type that could be returned to service if a means to join the broken surfaces were available, as fortunately it is in the low-temperature silver solder process; (2) the repair of tools that possess shanks, tangs, and other non-cutting portions that may be broken or damaged to the extent that only the addition of metal will permit their return to service; and (3) the repair of special rotating tools, such as end-mills and milling cutters, that may have portions broken from the cutting edges or have their edges so worn in service as to require building up.

Jan 1, 1943

By Angus D. Campbell

"IntroductionThe subject assigned to me tonight gives unlimited scope. The material available is so voluminous and leads into so many ramifications, and the memories of the Camp are so vivid and treasured, that it is difficult to decide just what to use. Then, too, the geologists are the story-tellers of our tribe - I am only a hard rock miner.Members of the Cobalt Branch and Cobalters everywhere will agree without question that this Cobalt camp has been the greatest of all influences on Canadian mining. To those who do not know Cobalt, our opinion may seem prejudiced and our statement exaggerated.Be that as it may, discussion on this subject can be profitable, since it is worthwhile now and then to think on 'whence we came' and 'where we are going'.In the revival of interest in the Cobalt camp, we hope our guests may feel some of the old Cobalt Spirit, which has become the Spirit of the North.Visitors may even, while here, catch a glimpse of that whimsical little guardian spirit of the camp - the original goblin, the Kobold - for which Cobalt was named.While Kobold brings that good luck which plays so important a part in mining, he can have his evil moments, as in his original German home. There, when he made the silver disappear from their good ore, they cursed the grey ore, calling it Kobold.Although this little goblin bas frequently upset our best mining plans and geological calculations, be has played the game as well. He placed •some silver on the surface, and when he hid ~t at depth he left dues .for its finding. He has rewarded many who sought his treasure and is still rewarding those who have persevered and had faith in him. t:lis influence and that of Cobalt camp has probably had a greater influence on your work and your mining areas than you realize"

Jan 1, 1950

By Sunil Koppalkar, A. R. Laplante

"A Pilot Plant was installed in one of the grinding circuits of the Dome Mill, Ontario, Canada. Tests were conducted on a KCCD12 Knelson Concentrator to systematically analyze the effect of operating variables on the performance. The main objective of this test work was to explore the effect of very coarse (6 mm) feed size on GRG recovery and performance of the Knelson concentrator. Preliminary results have shown that coarse feed size is deleterious to maximizing recovery. Size-by-size GRG recoveries have shown an unusual trend in the sense that recoveries do not decrease monotonically with decreasing gold particle size. Similar trend observed in one other full-scale unit has been compared. The observed trend is probably linked to the feed size distribution and top size.INTRODUCTIONKnelson Concentrators are the most widely used semi-continues centrifuge gravity separation units for the recovery of gold and platinum group minerals (Xiao and Laplante 2004). The main advantages over the competing centrifugal gravity units are their design, operating simplicity and good separation efficiency that make them the most common choice for gravity circuit. Despite some characterization at bench scale and a limited characterization at full scale, there is a lack of a comprehensive study of impact of operating variables on efficiency that reflects realistic full scale operating practice. GRG characterization studies, at bench scale, on these units provide information about the occurrence of gold in ore samples but fail to provide adequate information about the effect of operating variables for full-scale units. It is well known fact that such work is difficult to undertake on full-scale units owing to the difficulties involved in sampling and systematic variation of operating parameters. To tackle these problems, a pilot facility consisting of a 12-in CD Knelson Concentrator, a feed screen and tailing pump was installed in one of the grinding circuits of Dome Mill. This paper describes the work carried out and the results.Porcupine Joint Venture (PJV)Porcupine Joint Venture was formed in 2002 between Placer Dome Inc. and Kinross Gold Corporation. The JV utilizes the milling capacity of the Dome Mill to process ore from Placer Dome and Kinross mines. The Dome Mill circuit has gravity concentration, cyanidation and CIP circuits to recover gold. Gravity recovery has been used at Dome Mill since inception to recover gold: first by using conventional jigs, which were eventually replaced by two Knelson Concentrators in 1993, one in each of the grinding circuits. Three more Knelsons joined the circuit in 2002 to improve gravity recovery. An Acacia Intensive Leach Reactor was also added in 2002 to process gold concentrates replacing shaking tables (Chong et al 2004)."

Jan 1, 2007

By Paul Laframboise, Nigel MacDonald, Mike Hallewell, Robert Thorpe

"Galmoy Mine, owned by Arcon Mines Limited, has operated since 1997, and is one of three operating lead/zinc mines in Ireland. Changes in ore type starting in mid 2002 created challenges to metallurgical operations at Galmoy. This resulted in unacceptable lead and zinc flotation performance, which prompted initiation of a formal plant review and a subsequent stabilization programme. This involved a structured review of operational practices, development of a new Standard Operating Procedure (SOP) which in turn led to significant changes in process control equipment needs in conjunction with extension of zinc flotation cell residence time.This paper will describe the metallurgy of the Galmoy operation. Reasons for the poor metallurgy experienced in 2002 will be described, as well as the solutions identified to overcome these problems. By the second quarter of 2003, these solutions had been implemented and recoveries had risen to record levels.INTRODUCTIONGeneralGalmoy Concentrator is located in County Kilkenny (Refer to Figure 1 below) and was constructed during 1996 and commissioned in 1997.The concentrator at Galmoy had been designed initially to treat 650,000 tonnes per annum of primarily CW ore type. The main mineral of economic significance was sphalerite (Typically 10 to 11% Zn) with some minor galena (0.7%Pb) in a dolomite (Magnesium Carbonate) host rock.The only other competing sulphide mineral was pyrite (Circa 3 to 5% Fe in Mill Feed. This CW ore type predominated the first 6 years of production, but in August 2002, the ore mineralogy changed due to significantly higher levels of pyrite rich G ore body being blended in with CW ore."

Jan 1, 2005

By Tom Gabardi, Peter Clarke

"MillMapperTM is a new 3D laser scanning technology that has only recently been introduced into the North American mining industry. It enables mill operators to gain a much more complete understanding of the condition of their mill internals and to more accurately predict how liners will perform in the future. This paper describes the technology and techniques used to obtain data on internal mill conditions, how this data is processed into meaningful information which enables better prediction of liner life and gives examples of the reports provided by the software. Examples are given, using client sites data, on how this information is being used to reduce the costs and improve the revenue from SAG and ball mills.INTRODUCTION Scanalyse Pty Ltd developed the MillMapperTM technology in Australia over a number of years and has recently introduced it into North America with a significant take-up in Canada. The technology was commercially released in Australia in late 2006 and there has been significant technical development in the features provided since that time. MillMapperTM has been accepted as a useful technology in the Australasian region and more recently has been introduced to sites in Chile, Peru, Brazil, USA, Canada, Laos and South Africa. Over 100 different mills have been scanned and the technology has been thoroughly tested and validated. It has become an integral tool in condition monitoring and improvement programs for SAG and Ball mills across many sites and is now providing significant and measurable benefits to the mining industry. Some of these benefits will be described in this paper using actual examples."

Jan 1, 2012

By R. Al-Hent, M. Aissa, J. Asfahani

"This paper focuses on determining the favorable geological and hydrogeological conditions for forming uranium occurrences in the Froqlos-Jabal Abou Rabah region, Palmyrides, Syria. Eighty rock samples from this area were analyzed by spectrometric gamma-ray technique to determine the radioactive concentrations of eU and eTh, and of %K. Uranium concentrations in shallow and deep groundwaters were also determined. High uranium concentrations were registered owing to the presence of phosphatic outcrops in the study region. The uranium migration trends and its remobilization were analyzed through the analysis of the behavior of eU, eTh, and their ratio. A positive relationship between eU and eU/eTh, and a negative relationship between eTh and eU/eTh in geological formations of different ages supports the secondary remobilization of uranium. The role of groundwater movement in transportation and redeposition of uranium mineralization is discussed: deep waters are less oxidizing than near-surface waters, and do not appear to have significantly remobilized uranium. This indicates that the source of secondary uranium mineralization is surficial or near surficial, and is mainly related to the leaching of outcropping phosphatic layers.Integration of the results with established radioactive and geological sections reveals four radioactive anomalous zones: north Froqlos, Kherbet Hannora, northwestern flanks of Jabal Abou Rabah (Kherbet Al-Hajar), and the northwestern limit of the Ghuntor depression. The high uranium concentration in north Froqlos is because of its original presence in the phosphate beds and extensive fracturing, which allows groundwaters to penetrate and remobilize the uranium. High uranium concentrations in the other three locations are caused by the presence of evaporites and capillary action, which draws solutions upwards and causes redeposition as surface crusts (gypcrete)."

Jan 1, 2009