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By Ch. Wenzl

Anodes must have a certain physical and chemical quality in order to provide uniform anodic corrosion and meet the requirements of electrorefining, i.e. to achieve a high current efficiency, low energy consumption, low amount of anode scrap and low effort together with high cathode quality. Various properties of the anodes can be influenced directly by the casting process, which is the interface of pyro- and hydrometallurgy of copper. The aims of anode casting ? high output and long mould lifetimes ? are not consistent with good physical anode quality. The physical requirements of an anode are smooth surfaces, uniform weight and thickness, minimal edge effects, minimal distortion of the body and the lugs, as well as a homogeneous microstructure, in order to achieve uniform dissolution behaviour. The chemical quality of the anode copper is a task of electrorefining operations, but the elemental distribution within the anodes, which should be as homogeneous as possible in order to provide uniform anodic corrosion, can be influenced by the casting process.

Jan 1, 2007

By R. J. Rotzinger, K. W. Major

The Gibraltar Mine and Mill facility were commissioned in 1972 by Gibraltar Mines Ltd utilizing a flowsheet consisting of two stages of crushing followed by a rod mill / ball mill grinding circuit. During operations a number of opportunities were evaluated to expand the mill capacity; however, the economics of the day did not allow any of these projects to proceed. The mine continued to operate until late 1998 when it was shutdown and put on care and maintenance due to low commodity prices. Taseko Mines acquired Gibraltar in 1999 and in 2004, with the improvement in the metal markets, made the decision to restart operations. During the restart planning a number of opportunities for mill improvements and upgrades were identified and, after operations were successfully restarted, the decision was made to once again review expansion opportunities for Gibraltar. Taseko evaluated various expansion alternatives eventually deciding to install a SAG Mill, convert the existing rod mills to ball mills and distribute the SAG discharge to the resultant six 6 parallel ball mills. This paper discusses the design, implementation and commissioning of the SAG mill grinding circuit.

Jan 1, 2012

By R. Bonifaz

The Chagres Smelter, part of the Anglo American plc group situated 80 Km north of Santiago in Chile, completed a series of operational improvement in 2005 resulting in an optimum capacity in its operational units. At present the Chagres Smelter has developed an operational strategy which seeks to reduce bottle-necks in the production process. In this way we have managed to lower operational cost, decrease energy consumption and maximize the capacity of the Acid, Oxygen, and Smelting, Converting, Refining and Casting units. A constant application of international benchmarks together with continuous staff improvement and the latest smelter technology have combined to place Chagres among the finest smelting works in the world. In response to environmental challenges, we have studying various options for investment suitable for a profitable business of benefits to both Anglo American and Chile as a whole. The most relevant technical indicators are the figures : Energy consumption less than 6,3 GJ/ton fine copper, Intensity of smelting rate in Flash Smelting unit of 6900 ton of copper concentrate/m2 settler of furnace area and be one of the top five smelter in direct cash cost .

Jan 1, 2007

By J. S. Scott

"The Quemont property comprises 640 acres lying directly north of and adjoining the Noranda (Horne) mine. During 1926 to 1928, United Verde Extension Mining Corporation sank a shaft 235 feet and did 3,000 feet of development work on the 215-foot level. Between 1929 and 1930, Quemonr Mining Corporation deepened the shaft to 926 feet, and did further lateral work and drilling on the 500- and 900-foot levels. This work was confined to an area close to the south boundary and met with little encouragement.Following a period of idleness a magnetic survey was made in the winter of 1944, followed in the summer of the same year by some 6,000 feet of drilling. The first successful hole was drilled in February, 1945, from the ice of Osisko lake.To the time of writing, 131,000 feet of drilling, surface and underground,have indicated a large tonnage of gold-silver-copper-zinc ore, and although some knowledge of the geology and structure is emerging, it is too early to draw definite conclusions. The following brief description deals only with those structural features that are reasonably well indicated."

Jan 1, 1954

By W. E. Cockfield

"The Last Chance claim is about 13 miles north of the village of Nicola and northeast of the city of Merritt; in the south-central part of British Columbia. It lies within Nicola mining division on the northern slope of Swakum mountain; near its summit. It may be reached by means of a branch road from the Kamloops-Merritt highway that leaves the highway at Nicola.The property was originally staked as a copper prospect by Oscar Schmidt in 1916. A number of cuts were driven and a test shipment of 22 tons of ore, averaging 4.6 per cent copper, was made from the surface showings. The property was then optioned to Granby Consolidated Mining, Smelting and Power Company, Limited, who did a small amount of drilling, after which the option was abandoned. The same year an option was secured by Northwestern Mines, Limited, of Spokane, and a SO-foot shaft was sunk. This option also was abandoned and after a number of years the property lapsed, but was re-staked in 1942 as a tungsten prospect along with other claims, and was drilled for the Metals Controller in 1943."

Jan 1, 1954

By D. A. Akinlade, N. L. Richards, D. C. Murray, W. F. Caley

To investigate the effect of adding Ti to a Ni-Cr-Fe powder metallurgy alloy, a thermodynamic software package was used to predict the phase transformations that occurred during thermal processing. Specifically, the effect of adding 3w/o Ti to a 6w/o Al modified ternary Ni-Cr-Fe alloy (the quaternary) was simulated and the phase transformations that might occur in the material on sintering were obtained using the thermodynamic modeling tool. These predictions were subsequently compared with experimental results obtained by X-ray diffraction and metallography. For comparison, selected compacts were prepared containing only the ternary + 3w/o Ti (no Al). Based upon compressibility curves, the optimum pressure for producing the new Ti compacts was 500 MPa vs 600 MPa for the quaternary composition with Ti. In each case, hardness of the base alloy was enhanced by the Ti addition whereas the residual porosity remained relatively constant at about 19%. Finally, although SEM/EDS failed to confirm the presence of Ti in the gamma prime intermetallic, XRD spectra showed a shift in lattice parameter on addition of Ti, suggesting that the intermetallic was of the form Ni3(Al,Ti).

Jan 1, 2010

By J. Mosher, G. Banini, J. Hollow, A. Villanueva

Prior to installation of High Pressure Grinding Rolls (HPGR) at PT Freeport Indonesia (PT-FI) a series of laboratory tests were carried out to determine the design parameters and also determine key performance indicators (KPIs) for the industrial unit. The design parameters derived from the lab test work were then scaled up to estimate the industrial capacity of the HPGRs to be installed. These parameters include specific power draw, specific throughput, and specific force, rolls speed, product size distribution and wear rate of the rolls. This paper compares the performance of the scale-up procedure against the installed industrial size HPGR. Overall, the specific throughput of the industrial size HPGR is higher by a minimum of 30% compared to the expected scale-up value. As a result of the high specific throughput, the specific power draw and grind sizes are below the scale-up expectations in the commercial application. The impact of these factors also contribute to a lower than expected wear rate on the industrial rolls. Installed rolls achieved a service life in excess of 18,500 hours relative to the target of 6,850 hours predicted from the laboratory testing.

Jan 1, 2012

By Lyall J. Lichty

THE property of New Calumet Mines, Limited, is on Calumet island, in the Ottawa river, about sixty-six miles northwest of Ottawa. Lead and zinc orebodies were discovered here in 1893. A gravity concentration plant was built in 1912 but was not a success metallurgically, and the plant was later destroyed by fire. A programme of diamond drilling on the property, started in 1937 and continuing to 1942, indicated ore reserves amounting to 1,300,000 tons averaging 2.75 per cent lead, 8.82 per cent zinc, and 0.041 oz. gold and 6.24 oz. silver per ton( l ). These orebodies have been developed underground by cross-cutting and drifting from a three-compartment vertical shaft, sunk to a depth of 745 feet. 'The ore is a contact metamorphic deposit occurring in rocks of the Grenville series, on or near the contact between biotite gneiss and an overlying calcareous amphibolite(2,3). It consists chiefly of iron-bearing sphalerite, galena, pyrrhotite, pyrite, and minor amounts of chalcopyriteand argentite. The gangue minerals closely associated with the ore are calcite, quartz, and various lime-silicate minerals.

Jan 1, 1945

By Selvia Tourn, Liliana Castro

"Abstract - Argentina, a large country with an important agriculture industry, needs an ever-increasing amount of phosphorus and potassium, as essential elements for plant growth. Current requirements are met from imports, but potential resources exist in Argentina. For example, several phosphatic occurrences are known in paleo-marine basins, the most significant of which are in Tertiary units in Patagonia. In addition, two types of potassium deposits are also known in Argentina: evaporite deposits in the Neuquén Basin at depths of 750 m to 1500 m contain 22 to 25 wt% K2O equivalent; and glauconitic sandstone containing about 6 wt% K2O has been identified in Patagonia.Several experiments were undertaken to test unprocessed phosphate rocks as slow-release, direct-application fertilizers, with good results. In addition, it is proposed that direct application of glauconitic sands would provide an efficient and economic alternative source of potassium. Tests with glauconite samples are still in progress. The existence of both phosphate and glauconitic rocks in Patagonia suggests that development of an extractive industry for these materials would not only help Argentina approach self-sufficiency in fertilizer usage, but also assist in the socio-economic development of this region."

Jan 1, 2003

By D. Asefi

A new method to detect microstructural features such as recovery and recrystallization as well as cold rolling reduction in low carbon steels was developed based on magnetic hysteresis loop measurement. To this aim, a hysteresis loop measuring apparatus, specifically designed and assembled for plate samples was employed. It is shown that maximum field (Hmax) of hysteresis loop, measured at constant maximum flux density (Bmax) of 0.5T, is an adequatemagnetic property to monitor different stages of changing microstructures during annealing.

Oct 1, 2011

By Donald MacFadgen

Since 1950, a total of 164 miles of levels and rooms have been roof-bolted in the collieries of the Dominion Coal Company. Roof bolting is an efficient and economic method of sup-port where heavy timber sets or steel booms are necessary for temporary roof support, or where conventional methods of support interfere with the passage of mechanical mining equipment. This paper discusses present roof bolting practices and special bolting applications. THE practice of roof bolting in be collieries of the Dominion Coal Company dates from 1950, when preliminary studies and experiments were carried out in a mechanized room and pillar section of Dominion No. 20 Colliery. These studies were made in close liaison with members of the United States Bureau of Mines who were conducting similar studies. Following the successful application of roof bolting in No. 20 Colliery, this method of roof support was introduced into other collieries

Jan 1, 1963

By Yuhua Wang, Wei Sun, Dongfang Lu, Yuehua Hu, Tao Jiang

"With the continuous depletion of high-grade tungsten ores, the low-grade refractory wolframite has become an important source for the tungsten industry. However, the large-scale utilization of low-grade refractory wolframite is disappointedly scarce, it is due to leanness of valuable minerals, complex mineral characterization and use of toxic collectors.The aim of this study was to develop an environment-friendly processing flowsheet, which was used for beneficiation of low-grade tungsten ore containing 0.45% WO3 from New Brunswick in Canada, and the content of arsenic is 0.68% in this materials. The objective of beneficiation studied was to obtain a concentration containing 60% WO3 with less than 0.5% of arsenic under the condition without any flotation reagents. In this environment-friendly processing flowsheet, magnetic separation technology, classification and gravity separation technology were combined and employed. Firstly, magnetic separation was employed for the first pre-concentration process, over 95% of the feed was rejected as the final tailings, meanwhile, over 85% of arsenic minerals were removed with tailings. Secondly, gravity separation tests were employed on the classified magnetic pre-concentrate in the second pre-concentration process, a second pre-concentrate with WO3 grade of 54.32% and As grade of 5.41% was obtained. Finally, two stage magnetic cleaning were conducted on the second pre-concentrate for upgrading the second pre-concentrate, the mostly arsenic and gangues were removed from the second pre-concentrate. Finally, this novel processing achieved an effective recovery of fine wolframite from low grade tungsten ore with high arsenic. A concentrate with WO3 grade of 64.81% were obtained in new opened processing flowsheet, and As grade was less than of 0.5% in this concentrate. Furthermore, remarkable feature of this processing flowsheet is environment-friendly due to avoid using the toxic flotation reagents during the whole mineral processing.INTRODUCTIONTungsten is an essential metal and is the most widely used in industrial production such as national defense, electro-mechanical products, textile and leather sectors (Srivastava et al., 2000). Wolframite and scheelite are the main mineral sources of tungsten metal. With the continuous depletion of high-grade tungsten ores and the increasing demand for tungsten alloy, the low-grade refractory wolframite has become an important source for the tungsten industry. However, the large-scale utilization of low-grade refractory wolframite is disappointedly scarce, it is due to leanness of valuable minerals, complex mineral characterization and heavy use of toxic collectors."

Jan 1, 2016

By Denis Beaudoin

Program Basics: Goals, Course Content & Training Process Sudbury: History of the Program & Lessons Learned Diavik: History of the Program & Lessons Learned Most Recent Program: Totten Mine in partnership with Sagamok Anishnabek Summary -Lessons Learned Conclusion

Oct 1, 2010

By D. S. Conochie

The world is poised for rapid growth in consumption as large, less developed economies acquire greater wealth. It might be expected that there would be a corresponding growth in waste generation, but this might not necessarily be the case. The metallurgical industry has an excellent record of process development which has allowed it to provide a high tonnage supply of low cost, high quality metals. Environmental challenges have been faced and indeed the recycling of scrap iron through the electric arc furnace has made a massive contribution to cleaning up obsolete structures and equipment of past generations. Issues in waste generation and processing still remain, and the expectation for cleaner processing and environmental performance continues to rise. The waste impact of key process developments of the last century and the recent developments in metallurgical waste processing in Canada will be outlined. The potential to use state of the art design tools to produce the next generation of zero waste processes will then be explored.

Jan 1, 2004

By Y. Hou, E. Arinaitwe, L. Tong

A series of dense medium separation (DMS) tests were performed on four low-grade copper ores from Mount Polley mine in order to determine their amenability to pre-concentration. The tested ores contained disseminated sulphides, mostly chalcopyrite with low copper grades (0.15% - 0.2%) and relatively high iron grades (4.76% - 5.63%). The samples were screened into different size fractions ranging from 9.5 mm to 50.8 mm and DMS tests were performed on each size fraction at various separation densities. The pre-concentration efficiency at different size fractions and separation densities was evaluated in terms of metal upgrading and distribution. Mineralogical tests were also performed on selected DMS sink and float samples in order to understand the influence of mineralogy on the pre-concentration efficiency. The results showed that significant copper upgrading was achieved for intermediate size fractions only at the highest separation density tested. The copper recoveries generally increased with particle size at all separation densities. However, it was impossible to upgrade the copper content in the ores and achieve acceptable recoveries and mass rejections at the same time. Copper recoveries and grades showed a strong correlation with iron recoveries and grades indicating that it is possible to pre-concentrate copper by recovering magnetite and other iron-containing minerals in the ore. Overall, the results suggest that the optimum separation density and pre-concentration efficiency is a function of particle size, and that the ore mineralization properties limit the performance of DMS as a pre-concentration technology for such low-grade disseminated ores.

Jan 1, 2014

By Arnold R. Miller

Overview ? Vehicle Projects LLC (prime contractor) and the Fuelcell Propulsion Institute have developed the world?s first fuelcell locomotive. ? Principal applications are underground mining and tunneling. ? Because fuelcell vehicles solve the problem of underground emissions, mining is expected to be their first commercially viable market. ? The first year of a three-year project to develop a fuelcell mine loader is funded and underway.

May 1, 2002

By Karl J. C. Harries

"The following is an outline or check sheet of some things that might be looked at when considering the concept of a royalty or royalty provisions. It is not intended as a guide to what is right or wrong (that is for the parties to decide). It does not replace the discussions in this work and is not intended to be a complete or exhaustive compilation of matters to be considered. It presumes that you are familiar with the basic concepts of royalties and has been included as an aide memoire only. Use it as such, with caution and common sense, and amend it to suit your needs. Remember also that brevity can result in inaccuracy or imprecision. This is a danger in many points below.The section references are for the sections where the matter is the main subject of the section – see the index for other sections.Royalty TypesNet Proceeds [§§ 5.8.; 11.4.]• No accepted or understood meaning within industry.• Literal meaning, if not defined, would imply “net operating profit”.• Often defined as net profit with revenue base of proceeds from sale of product.• Should not be used without detailed and clear definition. Net Operating Profit [§§ 5.8.; 11.4. – referred to only]• Net profit without recoupment of pre-production expenditures.• Revenue base: usually proceeds from sale of product.• Operating costs deductible.• Some reserves may be permitted.• Recoupment of some post-production capital expenditures may be permitted.• Not often seen as basis for royalties in Canada."

Jan 1, 2003

By H. Sakurai, M. Kato, F. Tanaka

The Mitsubishi Continuous Copper Smelting/Converting Process employs an electric furnace (CL- furnace) for settling the slag/matte mixture formed in the smelting furnace. The conditions in the CL- furnace change its settling efficiency, resulting in high variability of copper losses in slag. Modifications of the operation and maintenance procedures for the CL-furnace have significantly and sustainably reduced the copper losses in Gresik smelter to below 0.7%. A series of flow patterns evaluation in the CL-furnace demonstrated how the chemical reactions and settling conditions of the CL-furnace has been improved by the new operating procedures. Settling mechanisms for the matte droplets in the CL-furnace is also discussed using image analysis of solidified slag. INTRODUCTION The Mitsubishi Continuous Copper Smelting/Converting Process employs an electric furnace (CL- furnace) for settling the slag/matte mixture formed in the smelting furnace. Since the top-blowing in the S- furnace agitates the molten bath strongly, matte droplets are dispersed over the slag phase when melts flow out of the S-furnace. Thus, the CL-furnace has an important role to settle and recover matte droplets efficiently. Since many papers have ascribed major part of copper losses to matte droplets suspended in slag (Tanaka 2007; Genevski et al., 2008; Starodub et al., 2016), flow patterns of slag in the CL-furnace can affect greatly on the profitability of smelters which have adopted the Mitsubishi process. PROCESS DESCRIPTION Figure 1 illustrates the Mitsubishi process schematically. The Mitsubishi process is the only system for continuous production of blister copper from copper concentrates and consists of 3 furnaces connected by enclosed launders those ensure the minimum emission of fugitives. In a smelting furnace (S-furnace) copper concentrates are fed with flux, oxygen-enriched air to form a mixture of slag and matte which cascades down to a slag-cleaning furnace (CL-furnace). The CL-furnace settle matte droplets in the mixture on the crucible from which matte is siphoned to a converting furnace (C-furnace), while discharging the cleaned slag (CL-slag). The C-furnace converts matte to blister copper by the top-blowing of oxygen- enriched air.

Jan 1, 2019

By Chris M. Healey

"The Jasper Gold mine in northern Saskatchewan produced a total mill feed of 140 127 tonnes at an average grade of 19.0 g/t Au. Both diamond drilling and chip samples from underground workings returned extremely high values, up to 12851 g/t (375 oz/T) Au over 0.10 meter from a chip sample. In the presence of such extremely high grades, the accurate estimation of reserves is a major problem.In the first part of this study, production data from the mine were used to evaluate the results of a variety of reserve estimation techniques in this environment. In two out of three cases studied, indicator kriging with assays cut to 342.9 g/t (10 oz/T) gave extremely good results. In the third case, however, indicator kriging gave unacceptable results. Instead, lognormal kriging of uncut data gave the best results.Secondly, from the same database, a number of drill-hole spacings were simulated, and reserves estimated from the simulations. As may be expected, the results of this analysis show increasingly better results with tighter drill-hole spacing. However, even with a 5 m by 5 m spacing the variation from actual grade was quite large. This is not a systematic under- or over-estimation of grade, rather a random scatter of results.The results of this study show very clearly the problems of deriving good estimates of reserves when extremely high-grade samples are encountered. There is a high degree of randomness to this data base, so reserve estimation in this situation will remain a high-risk operation."

Jan 1, 1993

By J. Edwin Van Buskirk

For a country that is as important a gold producer as Canada, the return to the gold standard of the major commercial countries of the world during the past five years is of particular significance. To the Canadian gold mining industry, the advantages of the gold standard are a matter of more than theoretical importance. According to economic theory, prices are determined by the relation between the demand for, and the supply of, money. The demand consists of the offering of goods for money; the more goods offered, the greater the demand. The supply consists of the total money available for the purchase of goods. The total supply of goods to be exchanged through the instrumentality of money remaining the same, an increase in the supply of money will, according to this theory, raise prices; conversely, a decrease in the supply of money will lower prices. Let us imagine that everyone in the world suddenly had twice as much money, and that the sum total of all goods remained the same. Is it not obvious that we would pay just double the price for these goods? In Canada today, most people have approximately 50 per cent grea.ter income than in 1913, and the average price for all articles sold in Canada is 50 per cent above those in 1913.

Jan 1, 1928