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By A. A. Bakke

"The Fort Knox gold deposit is hosted within the Fort Knox Pluton, a Cretaceous multiphase granitic body that intrudes the Fairbanks schist. Gold occurs along the margins of stockwork veins and veinlets, quartz-filled shear zones, and along fractures within the granite. The mineralization is generally sulphide-poor and closely associated with trace amounts of bismuth, tellurium and to a lesser extent with molybdenum and tungsten. At present, proven/probable reserve estimates, based on a cutoff grade of 0.39 g/t Au, are 158.3 million tonnes grading 0.83 g/t Au.The Fairbanks schist comprises the bulk of the country rock. The dominant lithologies present include muscovite-quartz schist and micaceous quartzite. Immediately north and south of the main orebody, mixed metamorphic lithologies of the Cleary sequence, a subunit of the Fairbanks schist, have been mapped. Development of local zones of weakness, most likely due to a broad regional warping event, resulted in brittle-ductile deformation and activation of a northwest-southeast shear couple between contrasting lithologies.The Fort Knox Pluton consists of at least three phases based primarily on textural differences. Intrusion of a fine-grained granite was followed by a medium-grained porphyritic granite. The youngest intrusive phase is a coarse-grained, seriate porphyritic granite, the Vogt Stock. The Vogt Stock forms an elongate dome with the axis in the east-west direction. Structures displayed in the overlying units, believed to be the result of doming, include tension fiSSUres and longitudinal fractures.Premineralization fractures, the result of the magmatic doming, provided conduits for initial stockwork quartz vein development and quartz enrichment in shear zones. Weak development of vein-controlled phyl/ic, potassic, albitic, and argillic alteration styles are present. Evidence of a late thermal event resulting in a low-temperature alteration assemblage of calcite + zeolite (stilbite) + chalcedony + clay occupies breccia zones, joint surfaces, and fractures within the granite."

Jan 1, 1995

By M. Hamamoto, M. Furuta, S. Tanaka

The Tamano smelter and refinery has expanded its production from 228kt/y to 260kt/y since 2006. It was not a big jump, but efficient and economical improvements were executed. These were not only de-bottlenecking and modernization of the smelting plant, including the acid plant, but also additional processes were commissioned, e.g. slag cleaning furnace and steam dryer. On the other hand, a conversion to permanent cathode process in the #2 tank house made the biggest impact on production efficiency for the refinery plant. In order to overcome the drastic change of copper business, although each scale is not so big, continuous improvements are very important to survive. This paper mainly describes the recent improvements of the smelting plant.

Jan 1, 2007

By R. B. Allen, E. E. N. Smith, B. C. MacDonald

"LocationTHE MAIN PROPERTY and townsite of Eldorado Mining & Refining, Limited, Beaverlodge Operation, is on the north shore. of Beaverlodge lake, •about seven miles north of the deserted town of Goldfields on lake Athabasca, and four hundred and ninety air-miles equidistant from Prince Albert, Saskatchewan, and Edmonton, Alberta. Both Eldorado Airlines •and Canadian Pacific Airlines maintain scheduled flights from Edmonton to the 4,000-foot airstrip on the north boundary of the Company property. Bi-weekly flights are made by Saskatchewan Government Airways from Prince Albert. Men and priority freight are flown by Company aircraft direct from Edmonton. From June to-September, when the waterways .are ice-free, freight is carried by barge from the •railhead at McMurray, Alberta, down the Athabasca river to Chipewyan, and across lake Athabasca to• Bushell, the terminal on Black bay, lake Athabasca, a total distance of 265 miles.The Eldorado Operation has been connected by a 12-mile, all-weather highway to Bushell. Where the highway crosses the park-land along the Fredette river, the townsite, Uranium, is under construction to provide services to the uranium-producing district. Spur roads have been built to the Ace, Fay, Eagle, •and Martin mines of the Eldorado operation, and to the properties of Pitch-Ore Uranium Mines, Ltd., and Rix Athabasca Uranium Mines, Ltd."

Jan 1, 1954

By K. Mayhew, A. Lossin, H. Salomon-de-Friedberg

"The proportion of arsenic-bearing copper concentrates that supply the copper industry is on the increase. The current strategy of miners and smelters to blend feeds to reduce average arsenic levels is rapidly becoming unsustainable as more concentrates with even higher arsenic levels enter the marketplace. In addition, the capability of smelters to manage increasing arsenic levels to more stringent and restrictive environmental standards is limited by available process technologies.CESL Cu-As Technology is a viable technical and economic alternative to traditional smelting. It offers the advantage of simultaneous leaching and precipitation of the arsenic in a single processing step while achieving high copper extractions. The process has been piloted in six separate, fully-integrated pilot campaigns for feeds ranging from ~1% to 12% arsenic in concentration. This paper will focus on the behaviour of arsenic in CESL’s leaching/precipitation step and operational factors that influence it, and on the chemical and physical characteristics of the subsequent iron-arsenic residue that represents today’s best available technology from a long-term sustainable (capital/operating costs, metal recovery, safety, environmental) perspective.The examples provided will demonstrate copper extractions approaching 99% and arsenic deportment to residue of 99%. Instantaneous settling rates of the residue were measured at 15+ m/hr. Data from subsequent short and long-term stability testing of the residue confidently support the view that the scorodite-bearing residues from the process will be stable and provide an acceptable arsenic management practice. The technology offers increased revenue and environmental certainty for miners, smelters & refiners to support the development of metallurgically challenged copper-arsenic deposits. Furthermore, results will be presented demonstrating the technology’s ability to successfully incorporate hazardous arsenic containing smelter by-products such as dust into the process feed and simultaneously extract copper value while fixing the arsenic in a stable residue."

Jan 1, 2016

By W. J. Jenner

"Introduction The Saskatchewan Power Corporation is a provincial crown corporation which operates under a mandate to supply all customers within Saskatchewan with electricity and natural gas. The Saskatchewan Power Corporation operates two coal mines within the province of Saskatchewan. The Souris Valley Mine is located a few miles south of the city of Estevan and produces approximately 300 000 Mg of lignite per year. The lignite is shipped about four kilometres by truck and burned at the 882 MW Boundary Dam Power Station, also owned by the Saskatchewan Power Corporation. The Poplar River Mine is located just south-west of the town of Coronach, Saskatchewan which is some 190 kilo metres west of Estevan. This mine produces approximately 1 675 000 Mg of lignite per year. The lignite is shipped seven miles by rail to the Saskatchewan Power Corporation's Poplar River Power Station. The Poplar River Mine is the sole sup plier of fuel to the Poplar River Power Station, which generates some 300 MW of electrical power. A second 300 MW unit is due to be commissioned at the Poplar River Power Station in mid-1983 and the Poplar River Mine will have doubled its capacity to approximately 3 350 000 Mg per year by that time: Souris Valley Mine Geology The Souris Valley Mine extracts lignite from the Estevan seam of the Ravenscrag Formation. This formation is of Tertiary age and was deposited during the Paleocene Epoch. The Ravenscrag Formation outcrops throughout southern Saskatachewan and all coal mined in the province occurs in this formation. Ravenscrag sediments are deltaic in origin and are composed of a series of fine sands, silts, clay and lignite deposits."

Jan 1, 1985

By J. G. Ross

A DESCRIPTION of the block-caving system of mining as practised at the King mine of Asbestos Corporation, Limited, Thetford Mines, Que., was presented. at the Annual Meeting of the Institute held in Quebec city, in April, 1934. The paper was published in the Transactions of the Institute for 1934. There has now been recovered, by this method, one million tons of ore, and a review of experience indicates that the method was well planned and has been executed smoothly. In approaching the problem of selecting the type of mining best adapted to this deposit, the method had to be one which would be low in cost, use no wood, and not disturb the surface immediately bounding the ore-body on two sides. Prior to 1931, block-caving had been considered but rejected, as it en-tailed disturbance of the surface area which lay within a 45° angle of the lowest contemplated workings, if the practice of such mines as Ray, Miami, Inspiration, and Morency, where this type of mining has been used extensively, was followed. At these properties there have been mined large tannages at outstanding low costs, but an extensive surface area has been disturbed in each case. In some instances, townsites in the mining area have had to be abandoned, and dwellings, not considered worth moving, have been allowed to fall into the depression. A study was made of the principles involved in the various types of block-caving, the existing information on ground movement, subsidence, etc., also being carefully analysed. Toward the end of 1931, a plan was conceived whereby the country adjoining ground being caved might be held permanently in place and undisturbed. The success of such a scheme was essential to the application of block-caving at the King mine on account of property boundaries, the Quebec Central Railway right-of-way, and expense of moving buildings. Study of existing data on caving and movement of rock, caused by sub-surface excavations of sufficient unsupported area to result in failure of the backs, indicated, in practically every instance, that such movements followed certain definite laws of mechanics.

Jan 1, 1936

By J. Ji, A. Shi, B. Grcic

Floating copper minerals selectively against iron minerals such as pyrite has been challenging for most copper and copper/gold deposits, and many operations continuously strive to maximise copper recovery whilst meeting target concentrate grades. Maximising grade is achieved by selectively floating copper minerals and rejecting pyrite. This challenge is to minimise copper and gold losses in the roughers if this approach is used. A flotation testing program was conducted by Bureau Veritas Minerals on a high-level pyrite bearing copper/gold ore sample to establish the potential to reject pyrite in the rougher stage, but also maximise copper and gold recoveries, and ultimately final product grades. The test program included feed characterization, rougher and open-circuit cleaner flotation as well as locked cycle flotation tests. The main variables tested for achieving selective flotation of copper and gold were collector type and pH control, through lime addition. Grind sizes used in the rougher and cleaner tests had been established from previous test work. The collectors tested were SIPX, Aerophine® 3418A, Aerophine® 3421, Aerophine® 3422, Reagent S-11192 Promoter, Reagent S-11193 Promoter and FloMin C4150. The two best performing collectors were then tested in open-circuit cleaner tests, with the optimum conditions examined further in locked cycle tests. INTRODUCTION Bureau Veritas Minerals Metallurgical Division was retained by Eldorado Gold Corporation to perform a metallurgical testing program on a high-level pyrite bearing copper/gold ore sample from a gold- copper porphyry deposit to optimize flotation reagent scheme to improve gold and copper recoveries and copper content in the concentrate. The test program included feed characterization, rougher and open-circuit cleaner flotation as well as locked cycle flotation tests. Initially, various collectors were screened in kinetic rougher tests, and over a pH range of 8.5 (i.e the natural ore pH) up to 11.5, using a primary grind size of 80% passing 120 µm. The collectors tested were SIPX (sodium isopropyl xanthate), Aerophine® 3418A, Aerophine® 3421, Aerophine® 3422, Reagent S-11192 Promoter, Reagent S-11193 Promoter and FloMin C4150. The enrichment ratio, which is the ratio of copper to sulfur in the concentrate to that in the feed, was used as proxy for rating selectivity (i.e. degree of pyrite rejection or depression).

Jan 1, 2019

The effect of long term exposure of full size bolts to corrosive environments is presented. A special test rig was used to test four bolts under different loading conditions. Four, X-grade identical profile bolts, each of 21.7 mm core diameters (23.7 mm full diameter) were subjected to prolonged corrosion testing using acid sulphate water. The pH value of the circulated water varied between 3.4 and 4.3. The corrosion exposure test period lasted three and half years. Two bolts were axially loaded to 10 and 20 tonnes force respectively, the third bolt was subjected to a 360 Nm torsion load and the fourth bolt was left unstressed to act as a reference bolt. After the test period ended, the bolts were stripped of their corroded coatings and weighted for weight loss. The diameter of each bolt was subsequently measured, and the loaded bolt samples were first tested non-destructively for tensile cracks and then tested for tensile failure. No cracks were found on post corrosion bolts tested non-destructively. The failure strength reduction on all four post-corroded bolts was significant, varying between 21% and 39%. The onset of corrosion was not confined to the targeted mid-section length of the bolt, however, the severest corrosion occurred at the anchored ends of the bolts.

Aug 1, 2013

By H. R. Taylor

The history and development of this property is more or less familiar to nearly everyone connected with the mining industry, so that only a brief outline of the more important facts will be given in this article. In 1916, a small pilot mill was constructed by the British Columbia Copper Company at Copper Mountain, and during 1916 and 1917 test work was conducted to determine the possibility of concentrating the ore and also to work out a suitable flow-sheet. In the spring of 1917, the location of a mill site at Allen by, which is about 8,% miles from Copper Mountain, and near the Similkameen river, was decided on, and the designing of a 2,000-ton plant was then worked out by Bradley, Bruff and Labarthe. Early in 1918, the actual construction of the concentrator began, and, after considerable labour difficulties, it was completed in 1920. During this period of construction, the West Kootenay Power Company ran a 60,000-volt power line over from Greenwood, a distance of 102 miles, and also built a sub-station at Allenby to take care of the mine and mill. The concentrator was started up on October 20th, 1920, and ran until December 11th, 1920, a total of 18,354 tons of ore being milled. The results of this short period of operation were encouraging, but, due to tlie prevailing low price of copper and high wages, it was necessary to shut down until a more favourable time. During the latter half of 1923, some work was done on remodelling the mill. This work continued until January 8th, 1924, when it was suspended.

Jan 1, 1929

By R. A. Rabnett, G. Paget, Patrick Walsh

"Tumbler Ridge, Canada's newest resource community, has been developed differently than have been other resource communities.Since its conceptualization, emphasis has been placed on the establishment of a traditional municipal government at early a stage as possible.Planning f or the community goes back to 1977. By then, extensive study by provincial agencies had shown a new resource town would be required to exploit north east coal. The Ministry of Municipal Affairs, in conjunction with a consultant named R.A. Rabnett began the extensive Tumbler Ridge conceptual plan.The results of the conceptual plan are evident in the organizational and planning goals of Tumbler Ridge. In every aspect from the election of officials to some financial matters, the town functions as a normal municipality. With the resource companies of the North East Coal Development within its municipal boundaries. Tumbler Ridge has been able to debenture its capital projects against its municipal tax base.The town's ability to function as a normal municipality is enhanced by its control over Crown land it has purchased from the province. This gives it further control over the development of the community and helps in establishing agreements with the resource companies and the provincial government to ensure that housing and service needs are met. While resource company representatives sit on certain municipal committees, their roles are advisory in nature.The community continues to move toward full municipal status and will have a fully elected Council by 1986.BackgroundPlanning for the development of northeast British Columbia coal resources began in 1976 under the aegis of the provincial Cabinet Committee on Coal Development. A series of subcommittees were established including a Townsite/Community Development subcommittee. The Ministry of Municipal Affairs chaired this subcommittee and continued as the lead agency for the provincial settlement planning effort over the period 1976 to 1981."

Jan 1, 1983

By A. B. Szwilski

"The various elements of longwall mine design are reviewed, particularly as they apply to condition s in the coalfields of the Plains region of Alberta. The following recommendations are made: (1) optimum panel lengths of 1000 to 2000 metres; (2) face lengths of 100 to 150 metres; (3) the use of retreat methods; (4) the restriction of floor undulations to less than 15 degrees. IntroductionThis article considers the elements of longwall mine design and is part of a short study that has been made of the feasibility of longwall mining in the Plains region, Alberta, Canada. The Plains region, with about 20 million tonnes, accounts for more than 80% of the coal resources of Alberta. The coalbearing strata in the Plains region cover an area of about 95,000 square miles. The geological formations dip very gently toward the southwest and, from a mining point of view, may be considered horizontal. The depth of the coal seams varies from several metres to over 650 metres. However, it is not anticipated that underground mining will be extended beyond the depth range of 25 to 250 metre s.The coal seams in the Plains region have been subject to many small mining operations in the past. The majority of these small mines were limited to a depth of about 50 metres, working mainly by room-and-pillar methods, although hand-filled longwall mining was often used.The development of new underground mining operations in the Plains region will have to be on a 'start-from-scratch' basis, especially regarding the installation of equipment. Longwall mining is more mechanized than any other method of mining and requires careful attention for the selection of new and expensive equipment. There have been many proven longwall advance and retreat systems in Europe and North America; mining conditions in the Plains region are more similar to those in the United States. Therefore, it will be essential for new mining pro jects in the Plains region to commence with proven system s and equipment; in time, perhaps an experimentation process could be attempted as experience is gained.Generally, the coal face is the key factor in mine productivity, which depends a great deal on equipment reliability, training and experience of the operators. The original design of coal faces must be flexible enough to cater for potential improvements so that running time can be increased."

Jan 1, 1980

By G. E. Agar, J. J. Barrett

"Traditionally, batch bench-scale flotation tests have been used for evaluating flotation reagents by comparing the results of tests done with various additions of the reagent in question. Usually, comparisons are made of the concentrate grade and recovery or some figure of merit involving an empirical combination of both. In some cases, statistical methods have been used to make the comparison and even to identify optimal combinations of reagents.None of the preceding technology utilizes the fact that flotation separations can be described by relatively simple kinetic equations that will serve not only to quantitatively describe the influence of a reagent, but will also aid in designing an optimal separation procedure. Examples of the use of a first-order rate equation for evaluating the impact of a reagent addition and for optimizing the reagent addition are given.IntroductionThe classical method of evaluating flotation reagents is to conduct batch bench-scale tests while varying one factor at a time. Some of the shortcomings of this technique have been pointed out and statistical design and evaluation of experiments has been advocated. Although the statistical approach is superior to the one-at-a-time method, it still is dependent on the results of a batch test conducted for a specific duration.That flotation is primarily a rate process than can be described by a first-order rate equation has been recognized for a long time, but the application of this knowledge to the evaluation of reagents has received little attention. In this work, it is demonstrated how the parameters of the first-order rate equation can be utilized to evaluate the influence of reagents on flotation."

Jan 1, 1983

By M. Jackman

"Froth stability is critically important for an effective separation of fine and ultrafine particles using column flotation. While a desirable froth stability is required to facilitate the drainage of entrained gangue particles for secondary cleaning, excessively stable froths could create problems in separation efficiency and down-stream processing. In this work, we demonstrate that a stable foam was produced using a poly (N-isopropylacrylamide) (PNIPAM) solution at the temperatures below the critical solution temperature. In contrast, very little foam was produced at the temperature above the critical solution temperature (~32 oC) of PNIPAM. We can also tune the foam stability by changing the temperature of wash water. When warm water of temperature of 50 oC was applied, the foam collapsed and diminished. This is probably attributed to the switching of PNIPAM molecules from coiled to a globule conformation as the temperature is increased. Our results indicate that the foamability and foam stability can be tuned by tempartureresponsive PNIPAM. This is the first time that thermo-responsive PNIPAM has been shown to have potential as a modifier of froth stability in column flotation.INTRODUCTIONIn mineral processing, column flotation has become a more prevalent process in the separation of fine mineral particles (typically < 100µm). Traditional flotation cells are sometimes less efficient in selective separation of ultra-fine particles (Kohmuench et al., 2009). The efficiency of flotation columns is dependent on the froth stability at the top of the cell to drain the unwanted gangue particles entrained in the froth. The greater froth height in flotation columns, compared to mechanical flotation cells, gives a longer froth residence time, allowing more of the drainage process to take place before the froth reports to the launderer. Secondary cleaning, by applying a wash water shower to the froth, enhances drainage of gangue particles entrained in the froth, and improves the recovery of the targeted minerals (Finch et al., 2007).While a stable froth is desirable to facilitate drainage of entrained gangue particles, greater amounts of fine particles have been found to contribute to excessively stable froths which could create problems for down-stream processes (Bethell et al., 2012). Operators have tried spraying additional wash water on the froth, and reducing frother dosage to destabilize the froth and to prevent backup at the launderer. The former is sometimes inefficient, and the latter results in unacceptable recovery loss. Currently, the best practice is often the installation of larger froth launderers, adding expensive defoaming agents, and/or using deaeration tanks (Bethell & Luttrell, 2005)."

Jan 1, 2016

By Leonard A. Wolff

"The 1980sfor the mining industry can be characterized as the survival of the fittest. High interest rates, low commodity prices, foreign subsidized competition and decreasing ore grades have contributed to a streamlining of the domestic mining industry in the United States, leading to the shutdown of operations or large cutback of work forces. The purpose of this paper is to look at the impact of a layoff on the employees of what was once a major uranium producer in south central Wyoming, twenty months after the final layoff and mine shutdown. INTRODUCTIONDecember 19, 1985, was the date of the final of three successive layoffs over a two-month period, leading to the complete shutdown of Petrotomics Company, a subsidiary of Getty Minerals Company. The final shutdown was due to a combination of depressed U3O8 prices and the takeover of Getty Oil Company by Texaco in January 1984.The layoffs affected 104 employees and included mine personnel, mill personnel and staff. Both hourly and salary workers were involved. The operation was considered non-union, however, a few mill hourly employees were unionized. At the completion of the layoffs. only a handful of employees remained for administrative and miscellaneous functions.For Getty employees, the terms of the merger agreement provided a generous level of separation benefits. The terms that were insisted upon by Mr. Petersen, Chairman of the Board for Getty Oil, stipulated that employees receive one month of severance pay, for each full calendar year of employment up to a maximum of two year&apos;s pay. This was the forerunner of what is now commonly known as the ""tin parachute”. All but the union employees of Petrotomics received these separation benefits. Union employees were covered by their separate, less generous, contract.Much of the literature that has been published in recent months has centred around the effects of layoffs on remaining employees, or the psychological effects on the severed employee. This study will emphasize the economic impact and ramifications due to a layoff, using the Petrotomics employees as a case example."

Jan 1, 1989

By R. Pot

"IntroductionTHE PURPOSE of this paper is to discuss briefly the main logging and testing devices presently at our disposal, to point out some of their limitations, and to suggest possible improvements of the techniques.Some of the more important devices .are those that are used in:(1) Coring(2) Formation testing(3) Electric well logging(4) Radioactive well logging(5) Measuring of bottom hole pressures(6) Sampling of reservoir fluidsThe first four of these procedures are concerned with the well while it is in the process of drilling. The last two are carried out as soon as possible after a well has been brought into production and .at intervals during its life. My remarks will be concerned mostly with certain aspects of formation testing. The reservoir engineer is dependent on the information derived from these operations in order to obtain a clear picture of the conditions in a reservoir and to enable him to assess and forecast its future behaviour.Since any calculation is no better than the data on which it is based, not enough emphasis can be placed on the necessity for the testing and logging equipment to be of the highest quality and for the analysis of the results obtained to be thorough."

Jan 1, 1952

By Xianglin Yang, Hong Zhong, Jingjing Xiao, Guangyi Liu

"The selective adsorption of a flotation collector to a mineral plays a crucial role in enhancing the hydrophobicity of targeted mineral particles for attaching air bubbles in pulp. The recent progress of the structure-reactivity relationship of flotation collectors, the characterization methods for mineral surfaces with adsorbed collectors and their commercial application are reviewed in this paper. Particular emphasis is placed on the density functional theory (DFT) for understanding the reactivity of new collectors, the surface analysis techniques including time-of-flight secondary ion mass spectrometry (ToF-SIMS), in situ scanning electrochemical microscopy (SECM) and atomic force microscope (AFM) to characterize mineral/collector interface, and the flotation technologies for optimizing recovery of valuable minerals. Especially, the recently developing collectors such as Gemini, alkoxyalkylthiourea, dithiourea, amide-hydroxamate and oximido-thiol surfactants, and their specificity to given minerals are evaluated. Based on this crucial review, it is evident that the structural modification approaches for minerophilic or hydrophobic groups, and combined surface analysis approach for further understanding the adsorption mechanism of collectors on mineral surfaces will lay a solid foundation for the future development of flotation collectors. INTRODUCTIONIn mineral processing, flotation is the main process for separation and recovery of valuable minerals from the ores contained them (Fuerstenau et al., 2007). One of the key requirements in flotation process is to increase selectively the surface hydrophobicity of the targeted minerals by collector adsorption so that these mineral particles can preferably attach to air bubbles in a slurry or pulp (Fuerstenau et al., 2007). Flotation collector is a kind of functional surfactant, which is composed of polar and non-polar groups (Somasundaran, & Wang, 2006). Non-polar portion, commonly being linear, branch or ring hydrocarbon group, is termed hydrophobic group. The polar portion, exhibiting strong affinity to mineral surfaces, is known as minerophilic group (Nagaraj, 1988). According to mineral types including saline, oxide and sulfide minerals, flotation collector divides into sulfide and oxide mineral collectors. For efficient recovery of valuable minerals from the refractory complex ores, insights into the adsorption mechanism, hydrophobic model and subsequent flotation approach of flotation collectors have been regarded as an indispensable issue in mineral processing."

Jan 1, 2016

By M. Brochu

In this paper, we present a computer-vision approach developed for wall-thickness measurements of corroded pipes inspected by double-wall radiography. The main objective of the work is to optimize data collection and film interpretation using computerized image analysis. To date, the system is able to identify the inner and outer contours of a pipe and perform wall thickness measurements at each pixel of a radiograph. This will be presented by analysing pipes having different dimensions. Another important feature of the system concerns the algorithms&apos; adaptability to pipe wall texture. In other words, image analysis is automatically refined around rough or corroded areas. This allows more precise thickness measurements and shape identification in critical sections as will be demonstrated with examples. Finally a brief overview of results exploitation will be given and compared with human interpretation. It will show the reliability of automated image analysis and the many possibilities offered by complete output analysis.

Jan 1, 2005

By William Petruk

Mineralogical investigations in connection with gold metallurgy are usually performed to find the reason for poor recoveries by cyanidation or by other leaching techniques. Poor recoveries most commonly are obtained when (I) native gold is encapsulated in an insoluble mineral as "invisible gold"; (2) native gold is coated with a precipitate; (3) gold-bearing products are insoluble in cyanide solutions; (4) carbonaceous material in the ore adsorbs gold; and (5) associated minerals decompose and consume cyanide. Samples of refractory material quite often have low gold tenors. It is difficult to find the gold-bearing minerals in such samples with an optical microscope because the probability of finding trace minerals in samples is small. The probability decreases with decreasing grain size of the gold-bearing mineral and with decreas¬ing gold tenor of the sample. Techniques have been developed to increase the success rate of finding gold grains; some are (1) concentrating heavy minerals; (2) preparing special polished sections; (3) searching with an image analyzer; and (4) dissolving associate silicate and sulphide minerals.

Jan 1, 1989

By K Komori

Naoshima Smelter and Refinery has treated shredder residue and incinerator fly ash in Japan since 2003. As a highlight, a new incinerating and melting furnace, as well as fly ash washing treatment plant were newly constructed for pre-treatment of shredder residue and fly ash respectively, and the pre-treated materials are ultimately treated in the existing Mitsubishi continuous copper smelting and converting process line. Since wastes such as shredder residue tend to vary in size and in shape, and contain some chlorine, the installation of a new pre-treatment line was required. The combination of the new pre-treatment line with the existing Mitsubishi Continuous Copper Process line has created a highly efficient and environmentally friendly system for recovering and recycling of valuable metals that previously used to be sent to a landfill. This paper reviews the approach that Naoshima took to establish its current recycling business strategy.

Jan 1, 2007

By Frank Ebbutt

In this paper it is proposed to point out certain structural factors that; have an important bearing on gold deposition. The subject will be treated; more or less generally. Although the writer has had access to a great many; of Canada's gold mines he does not wish to take the liberty of discussing; details of any particular mine or mines; the aim will be to discuss controls; that are evident in many places.

Jan 1, 1954