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By G. S. Hume

Introduction Core drilling of the bituminous sands of northern Alberta has been carried on by the Mines and Geology Branch, Department of Mines and Resources, under the supervision of the Director, W. B. Timm. This was part of the Dominion Government's wartime investigations, which included an agreement with Abasand Oils, Limited, for the study of commercial possibilities of obtaining oil from the bituminous sands. The drilling programme, commenced in 1942 by the Consolidated Mining and Smelting Company of Canada, was continued in 1943 and subsequently by Boyles Bros. under contract with the Mines and Geology Branch. Several areas have been investigated and one of these, the Mildred-Ruth Lakes area, ' herein described, is of special importance in that it contains a sufficiently rich and large deposit of bituminous sands and bitumen beds to warrant consideration of commercial developments for the production of oil. The Steepbank Area, East Side of Athabaska River The Steepbank area, on the east side of Athabaska river in township 92, about twenty-two miles north of Fort McMurray, was selected for drilling in 1942 because previous investigations by Ells indicated it was one of considerable promise both from the standpoint of having reasonably rich bituminous sands under relatively light overburden and also having an excellent tailing disposal and plant site for large-scale operations in proximity to Athabaska river. The drilling done in 1942 and 1943 was largely exploratory, and, when it was found that the southerly part of township 92 had only low-grade material, closer drilling was done in 1944-45 in the richer, more northerly part.

Jan 1, 1947

By I. G. Townsend, S. A. Buckley, C. I. House

"SummaryBritish Petroleum plc is developing a new gold recovery process known as coal gold agglomeration (CGA) for the recovery of gold from its ores. Liberated gold grains are recovered with high efficiency by adhering to agglomerates of coal and oil. The process is simple, can recover gold grains down to very fine sizes, avoids the large scale use of cyanide and provides the industry with an important new process option.A technical appraisal of the process has been performed on an extensive range of gold bearing materials. Ore types have been identified from which high gold recoveries can be achieved. A spreadsheet based computer program has been used to estimate the preliminary capital and operating costs of the process. Comparison with established gold production costs shows that the process costs of CGA, on the appropriate ore types, are potentially very attractive, which will enable economic treatment of lower grade ores than is currently possible using conventional cyanidation. Treatment of known placer deposits or gravity concentration plant tailings may be the most rapid means of demonstrating the process at a commercial scale prior to more widespread applications.1. INTRODUCTIONWestern world gold production for the 1980s has shown rapid growth sustained by a demand for gold at a favourable price (Fig. 1). Heap leaching and CIP/CIL operations have been responsible for the major part of new production during the 1970s and 1980s with present overall production costs averaging US$200/oz in Canada, USA and Australia and US$265/oz in South Africa [l]. A great deal of research and process development effort in the 1980s has been towards the treatment of refractory ores. Operating costs for the economic processing of these ore types by currently available routes are around US$300/oz [2]."

Jan 1, 1989

By Graham Davey

"Low speed stirred milling has been employed for many years in the metalliferous and industrial minerals industries. High speed stirred milling is a relatively new method of grinding in the metalliferous process industries. However it has been it has been in wide spread use in the industrial mineral field for over 30 years for various minerals. Many existing metallurgical operations are looking to maximize economic return from existing deposits, requiring new thinking and technologies. By combining low speed and high-speed milling fine and ultrafine grinding efficiency and operating costs can be improved.The correct selection of different fine grinding technologies is covered, when each mill is applicable and when a combination of the VERTIMILL® Grinding Mill and SMD provides the best economic solution.INTRODUCTIONUltra-fine grinding of minerals has been in wide spread use in the industrial mineral field for over 30 years. Within the last 10 years the metalliferous industry has shown interest in the ability to produce ultrafine particles, as chemical, physio-chemical and physical separation processes have advanced to be able to treat ultrafine metalliferous particles. Also as the primary mineral deposits, around the world are depleted, new more difficult deposits must be mined. Existing operations are also looking to maximize economic return from existing deposits, requiring new thinking and technologies.The traditional approach for gold containing refractory material has been to liberate the locked gold by chemically destroying the pyrite through oxidation. Roasting, pressure oxidation, and bacterial oxidation all employ various degrees of temperature, pressure and catalysis to react the pyrite with oxygen to produce iron oxide and sulfur by-products. However all of these methods are economically impacted due to specific operational added requirements and emissions controls. Pressure and bacterial oxidation have very high capital and operating costs."

Jan 1, 2006

By Douglas M. Smith, G. A. Maki

"The initial development of the massive potash deposits of the prairie evaporite formation took place over a decade ending in 1970. The potash mining and refining facility near Rocanvi11e, Saskatchewan was the 1ast of ten mines to come into production during that era. This operation, known as Sylvite of Canada Ltd., was designed to produce 1. 2 million short tons per year of KCl product in granular, coarse, standard and special standard grades.In 1977 the parent company, Hudson Bay Mining and Smelting, sold the Sylvite property to the Potash Corporation of Saskatchewan. Shortly thereafter PCS slated its new Rocanville Division for a two phase program of expansion. The first phase, completed in the spring of 1979, was relatively small, involving mill debottlenecking and additional equipment in the compaction circuit and the product and ore storage areas. The second phase was a major undertaking which included additional mining equipment and a new 300 STPH milling circuit. This work was completed during the fall of 1981 and has increased the Rocanville Division's nameplate capacity to two million STPY.Thickening equipment operating in the Saskatchewan potash industry is generally situated within the main refinery building or a separate insulated and heated structure due to the harsh winter climate and the need to closely control plant brine temperatures to ensure good flotation circuit performance. Since these thickeners process large volumes of slurries, conventional basin type designs tend to be large, ranging up to 150 feet in diameter or more. As part of the general effort to minimize capital costs, the potash industry has begun investigating the use of alternate high capacity, compact thickener designs. In this regard, PCS Rocanville undertook a program in 1978 to evaluate a Lamella™ Thickener and one other type of 'High Rate' thickener* as alternatives to a conventional design for the phase two expansion project."

Jan 1, 1983

By Hidenori Hatta, Takero Watanabe, Hideo Yoshida

"The effect of the quenching rate on age hardening in an Al-6.0mass%Zn-0.75mass%Mg alloy sheet was investigated. The quenching rates and aging conditions were as follows: water quenching (WQ) or furnace cooling (FC) followed by pre-aging at 20°C,then artificial aging at 120, 160 or 200°Cwere performed. The peak strength of the FC and the WQ are very similarat120°C aging. It is important high strength was obtained even at the extremely slow quenching rate. On the other hand, the strength of the WQ significantly decreased compared to the FCat200°C aging. GP(I) zones were formed during the pre-aging at 20°C even if the cooling rate was very slow like the FC, and were transformed into the GP(II) ones at 70°C or higher and then into the ?’ phase. However, these zones were dissolved by reversion during heating to 200°C. Thus the strength of the WQ decreased. On the other hand, it is considered that an unknown cluster or GP zone with a thermal stability formed during the FC was not dissolved up to 200°C and was transformed into the ?’ phase. Therefore, a higher strength was obtained in the FC for the200°Caging.INTRODUCTIONAl-Zn-Mg alloys are widely available in commercial production because these alloy have lower quench sensitivity and can be produced by air cooling (AC). Heat treatable aluminum alloys are usually produced by water quenching (WQ) to increase their strength because a high cooling rate inhibits the precipitation of the stable phase during cooling and increases supersaturated solute atoms. However, Baba(1967)reported the strength of an Al-6%Zn-1.8%Mg(mass%) alloy without additional elements quenched by very slow cooling (15°C/min) was 96% of that quenched by WQ. Furthermore,the age hardening at room temperature (RT) occurs after annealing at 410°C followed by furnace cooling (FC, 0.5ºC/min or less)in these alloys. Therefore, the process of annealing at 410 to 430°C for 120 min followed by AC, and reheating at 230°C for 240 min, then cooling is recommended in the specifications (Japan Aluminum Association, 2011). Matsuda and Yoshida(1996)also recommended annealing at 300°C for Al-Zn-Mg alloy extruded products to inhibit age hardening at RT by precipitating the solute atoms and decreasing them in the matrix. It has been considered that the higher the content of excess quenched-in vacancy becomes by WQ, the higher aging rate at RT is obtained. Therefore,it is theoretically and commercially important to clarify the reason why the age hardening occurs relatively quickly in almost no excess quenched-in vacancies such as the FC, and why the same strength as the WQ can be obtained in the FC"

Jan 1, 2018

By A. T. Jakubick, A. MacG. Robertson

This paper reviews key issues related to the placement of dry (soil) covers on extremely weak, compressible fine tailings. The design and construction of soil covers on such tailings often presents a formidable challenge to the geotechnical as well as the environmental engineer due to the low shear strength, poor traffic ability, and high settlement of under consolidated tailings at the time of reclamation. The geotechnical issues to be considered include: (1) consolidation of near-surface tailings to achieve strength gains, improve traffic ability, and allow safe placement of initial cover layer; (2) stability of tailings slopes during dewatering of tailings ponds and/or cover placement; and (3) long-term settlement of tailings and its impact on cover integrity and final surface shaping. The environmental issues to be considered include: (1) management of contaminated (free) pond water; (2) management of contaminated pore water expelled during tailings consolidation; and (3) management of (uncontaminated) surface water on top of the cover. This paper summarizes recent experiences gained in a large uranium tailings reclamation project. It is concluded that a careful consideration of both geotechnical and environmental issues during the planning stages greatly reduces the costs and environmental risks associated with fine tailings reclamation.

Jan 1, 2000

By M. Saghaeian, R. Hejazi, Fakoor Sanat Tehran Company, H. Abedini, M. Zare

"Dewatering of final tailings is one the biggest issues in iron ore processing plants. Because of the fine and hydrophilic particles in the iron ore tailings, dewatering of such material is difficult and, in most of the cases, needs to be processed using expensive and complicated equipment. In this study, a novel method based on classification of small and large particles has been proposed to improve the dewatering performance of iron ore tailings. In the proposed method, a hydrocyclone has first been used to separate the fine and coarse fraction of iron ore tailings. Then, the coarse fraction (hydrocyclone underflow) is easily dewatered by using vacuum belt filter. Then, the fine fraction (hydrocyclone overflow) is primarily dewatered by using a high rate thickener. Finally, the thickener underflow is added to the bed of solids on the same belt filter, which is used for dewatering of hydrocyclone underflow. The efficiency of this method has been compared with other solutions for tailings dewatering including changing vacuum filtration parameters, using fabric with larger pore size, and using pressure filtration, all through laboratory scale experiments on the tailings of an iron ore processing plant in Iran. The results indicated the superiority of this method compared to the other ones, which increased the specific filtration capacity of the tailings by around 46%.INTRODUCTIONWet beneficiation of minerals requires a substantial amount of water to enhance the efficiency of the process. Used water should be recovered at the end of process to minimize shipping costs, meet contract specifications, and reuse process water (Wills and Napier-Munn, 2006). Dewatering equipment is usually divided into sedimentation (thickening) and filtration (pressure and vacuum) equipment, the choice of which depends on particle size, solid content of slurry, and material nature (Mular et al., 2002)."

Jan 1, 2016

By B. C. Tripathy, S. K. Padhy, R. K. Paramguru, Pinak Patnaik

"Cobalt is regarded as technology enabling metal among the less abundant metals found in the earth crust. Electrodeposition of the metal from aqueous sulphate solutions is the preferred technology for its commercial production. Certain additives are added in the electrolytic bath during electrodeposition for the production of uniform, smooth and bright deposits of cobalt metal with higher current efficiencies and lower energy consumptions. A detailed investigation has been carried out to determine the effect of additive Sodium octyl sulphate (SOS) on the electrodeposition of cobalt. The results indicated that the additive apart from increasing the current efficiency enhanced the quality of cobalt electrodeposits. A maximum current efficiency of 98.4% was achieved at 10 mg/L SOS. The presence of SOS in the electrolytic bath did not result in any noticeable change in the crystal orientation of the cobalt electrodeposits except at higher concentrations (50 g/L) of the additive. Scanning electron micrographs indicate that smooth, compact and uniform deposits of cobalt were obtained at 10 mg/L of the additive beyond which there is detoriation in the quality of deposits. Polarisation of the cathode was seen in the presence of SOS. The effect of SOS on the electro kinetic parameters: Tafel slope (b), transfer coefficient (a) and exchange current density (I0) has also been investigated.INTRODUCTIONCobalt is recognised to be a strategic metal among the various base metals, owing to its numerous applications in various industries. Cobalt as a metal finds its use in the preparation of rechargeable batteries, as an alloying component in the manufacture of space craft and jet engines, as a drying agent for paint varnishes, ground coats for porcelain enamels and in the manufacture of the catalysts for the petroleum and chemical industries (Davis, 2000). Although there is a huge demand of the metal the supply of the metal is limited due to its scarcity in the earth crust. The metal comprises of only 0.02% of the earth’s crust for which the metal is recovered from various ores of nickel and copper as a byproduct (Hawkins, 1998). The present day techniques for cobalt production includes mostly hydrometallurgical methods which are preferred over the earlier used pryometallurgcial methods carried out for the metal production. Almost 70% of the world’s cobalt produced currently is from hydrometallurgical techniques in which electrodeposition of the metal from aqueous solutions is the final step for metal production (Verney, 1988). The most preferred route for electrodeposition of cobalt metal involves a sulphate medium (Das and Subbaiah, 1984; Lenthall and Bryson, 1997; Sharma et al., 2005)."

Jan 1, 2016

By D. B. Dreisinger, M. Rasouli

"Developing technology to address the environmental hazards associated with selenium in mine-impacted waters has been a serious challenge. Ion exchange (IX) has been identified as a potential treatment technology. This paper begins with a review on selenium adsorption with commercially-available basic anionic exchangers (BAS). It then looks at the use of resins for selenium removal via modification with the addition of -O, -N, or -S-containing chelating ligands and chelating polymeric ion exchangers pre-loaded with immobilized metal cations. The synthesis of chelating exchangers requires a final product with a highly stable metal in the ligand-metal complex. The nature, oxidation state, size, and affinity of the metal for the target oxyanions and the size, degree of protonation and space configuration of the oxyanion are among critical factors affecting the oxyanion uptake. There is a limited number of studies on the critical parameters affecting the selenium affinity for chelating exchangers. Such a study could fill in the gaps of our understanding of selenium-metal-chelating ligand interactions and assist in developing a new ion exchanger. In addition to commercial IX resins, layered double hydroxide materials (LDH) have received attention for oxyanion removal from waste water. The adsorption capacity of the LDHs are affected by the crystallinity of LDH, the nature of metal components, the ratio of metals, charge and type of anion, and the space between the layers. In particular, the Friedel phase (FP), a member of the LDH family, showed high adsorption capacity for selenate removal from synthetic solution. A study is currently underway at the University of British Columbia to investigate the effect of different synthesis methods and aging on the suitability of FP for selenium removal from mine waste water."

Jan 1, 2017

By F. Crundwell, N. Steenekamp

"The leaching of sulphide minerals generates a significant amount of energy. There are three systems that might be used to remove this energy. These are: cooling coils, quench water, and flash recycle. Flash recycle is the recycling of slurry from the autoclave to the feed tank. Heat is removed in this arrangement when the slurry at elevated temperature and pressure is flashed to atmosphere, releasing steam. The slurry is returned to the autoclave at lower temperature, resulting in cooling. The cooling is directly proportional to the steam released from the recycled slurry. Design equations and results for the flash recycle system are presented. A fourth proposal for removing heat is to recycle slurry from the back of the autoclave. These four alternatives not only remove the heat, but also have an effect on the leaching efficiency. Amongst the four alternatives, design calculations indicate that the flash recycle option is the optimal solution in terms of leaching efficiency and heat removal, and recycling product from the back of the autoclave is the worst. In spite of its efficiency in terms of heat removal and leaching, the implementation of the flash recycle system is limited to a few operations in the platinum industry.INTRODUCTIONIn considering ways to improve leaching operations, focus is placed on the chemistry, on the kinetics, the agitation and perhaps even on the gas mass transfer conditions. Attention is less frequently placed on the removal of energy from these reactors and how this might limit performance.The pressure leaching of sulphides releases a significant amount of heat. For example, the reaction for the leaching of chalcocite, Cu2S, given by"

Jan 1, 2012

By P. Roman, L. Daneshmend

"During the last decade, mining companies have been overwhelmed by technological solutions to perceived problems. This is particularly true with information technology where rapid advances have resulted in a professional climate characterized by technomania — the perception that failure to adopt emerging technologies will result in a loss of competitive advantage. This paper describes the applicability of structured analysis and design techniques as an appropriate methodology for integrating emerging technologies in the mining industry. The potential of this approach to improve overall mine effectiveness through improved communication and co-ordination between operations and maintenance is discussed. IntroductionA strong working relationship between the operations and maintenance departments in both open pit and underground mines is fundamental to the overall success of the mining endeavour. Unfortunately, for many mines, this characterization is far from accurate. Short-range production targets dominate the day-to-day management of the mines. This can be seen in Bostwick and Buchanan’s (1993) report on American Barrick Resources efforts to achieve an aggressive 415 000 tpd mining program at their Goldstrike operation in Nevada. When production managers do not meet their quotas, the finger is often pointed at maintenance. As a result, a confrontational culture can develop between the two organizations, resulting in a lack of cooperation that exacerbates the problem. Historically, production planning has taken priority over maintenance planning. This is reasonable since production is the primary purpose of the mine with maintenance serving in a support role. This basic relationship remains intact today. However, the trends toward mechanization, increasing levels of automation, and larger equipment, have resulted in increased reliance on the equipment used in the mine. As a result, downtime costs now go well beyond the direct labour associated with the repair of the machine. Lost production costs due to downtime resulting from failed equipment are becoming an increasingly important factor in determining a mine’s overall economic performance."

Jan 1, 2001

The properties required for a com-pound to form useful thermoelectric materials are described. Uranium compounds which might have these properties are reviewed. Several of these compounds have been prepared and fabricated into compacts. The apparatus used for hot pressing, and for the measurement of thermoelectric power, electrical conductivity and thermal conductivity, is described. Detailed attention has been given to the properties of the nitrides. Preliminary studies on a number of other uranium compounds are reported. The figures of merit of the best materials so far examined are one-tenth of those necessary for a useful thermo-electric material. THE efficiency of thermoelectric materials for power generation and cooling is determined by their figure of merit, Z = a2 a/K, where a, a and K are thermoelectric power, electrical conductivity and thermal conductivity, respectively. It is well known that the largest values of Z are achieved with semiconductors (1). High mobility of charge carriers is necessary for simultaneously high thermoelectric power and electrical conductivity.The properties required for a com-pound to form useful thermoelectric materials are described. Uranium compounds which might have these properties are reviewed. Several of these compounds have been prepared and fabricated into compacts. The apparatus used for hot pressing, and for the measurement of thermoelectric power, electrical conductivity and thermal conductivity, is described. Detailed attention has been given to the properties of the nitrides. Preliminary studies on a number of other uranium compounds are reported. The figures of merit of the best materials so far examined are one-tenth of those necessary for a useful thermo-electric material. THE efficiency of thermoelectric materials for power generation and cooling is determined by their figure of merit, Z = a2 a/K, where a, a and K are thermoelectric power, electrical conductivity and thermal conductivity, respectively. It is well known that the largest values of Z are achieved with semiconductors (1). High mobility of charge carriers is necessary for simultaneously high thermoelectric power and electrical conductivity.

Jan 1, 1963

By Dave Bulled, Khiratt Husain

"The use of High Pressure Grinding Rolls is gaining significant interest as a replacement for SAG milling in the comminution of hard rock ores because of the potential for reduced costs in terms of energy and grinding ball consumption. Estimation of expected energy consumption for fullscale operations has conventionally involved the testing of a few fairly large samples in pilot scale HPGRs. This paper describes the development of a small-scale batch test method for determining a work index for HPGR of a large number of samples that can be used to show the variability of the ore as an integral part of a geometallurgical approach to circuit design and production forecasting.The test equipment that was developed comprises a hydraulic press with adjustable pressure operating on small batches of ore in a locked cycle test procedure. A work index measurement was determined that links the specific energy consumed in the test to the breakage achieved such that the index can be used to predict comminution energy requirements.The measurements were calibrated against laboratory scale HPGR equipment to develop a model for design and forecasting that includes crushers, HPGRs and ball mills in a complete comminution circuit.INTRODUCTIONEstimation of the expected energy consumption for full-scale HPGR operations has conventionally involved the testing of a few fairly large samples in laboratory and pilot scale machines (Danilkewich, 2006). With the financial input of five mining corporations, SGS Lakefield Research has developed a small scale test capable of providing relevant information on the variability of energy consumption and size reduction from drill core samples. It is our intention that the values measured in the test will be scaled up, through benchmark comparison with pilot sized and full sized HPGR units, to allow plant design and throughput forecast on a block by block basis of the mine plan using a new CEET program. CEET® (an acronym for Comminution Economic Evaluation Tool) is an advanced grinding design and performance predicting tool that uses energy relationships to model the performance of SAG / Ball mill circuits."

Jan 1, 2008

By Belinda Campbell

Tools for Consistency 1. GIS Web Site 2. National Project Management System 3. Site Grouping Approach (721 PIDs) 4. Mine Reclamation Standing Offer Agreements ?Contracting tool 5. Remedial Objectives Guidance Document Background ?CBDC (now ECBC) is a Federal Crown Corporation and falls under federal jurisdiction. ?When it stopped mining coal, CBDC turned its attention to cleaning up and closing out its industrial sites. ?Public Works and Government Services Canada is common service provider to the GoC. ?Expertise in environmental, engineering, IT, project management, communications, GIS, real property management.

May 1, 2011

By M. A. Kessick

Current treatment and disposal procedures are compared for clay slimes resulting from the extraction of Alberta oil sands, the extraction of Florida phosphate matrix, the recovery of diamonds from kimberlite deposits in South Africa, the recovery of kaolin from clay deposits in southwest England and the upgrading of bauxite ore. Published research in the area is reviewed, and common trends which are emerging in the disposal of clay slimes are discussed.

Jan 1, 1978

By J. Lipp

The lion share of lithium produced globally originates from South American salars. The standard operation for lithium production utilizes an array of evaporation ponds. This process consume vast areas and is either very slow when relying on solar evaporation - roughly 18 months of residence time; or with very high energy consumption since over 90% of initial water volume needs to be evaporated. A new technology, based on solvent extraction was developed. Results indicate a distribution coefficient up to 30, and selectivity greater than 1,000 towards Na extraction. The loaded solvent is stripped using a strong mineral acid, and the product solution is the lithium derivative of that stripping acid. Utilization of this new LiSXTM technology results in reducing the area needed for a commercial plant as well as reduces the residence time. In addition applying different stripping acids can diversify the product line of such facility.

Jan 1, 2014

By ANNE FUZESY

Soluble potassium salts in bedded underground salt deposits supply most of The world demand for potassium f or agricultural and industrial use. The potassium salts, sylvite and carnallite, were f irs, noted in drillcores in southern Saskatchewan during The search for oil and gas in ihe early /940s. Problems in shafi sinking beset pioneering potash companies, however, and cominuous production did no, begin uniil 1962. Powsh deposits in southern Saskatchewan occur within ihe uppermost 60 111 of the Middle Devonian Prairie Evaporite a, depths in excess of 900 m. Four groups of po/ash-bearing haliie beds have been distinguished: the Esierha-::,y, White Bear, Belle Plaine and Paiience Lake members. Powsh deposiis extend a jell' kilomeires into Manitoba and south imo orth Dakoia and non heasiern Moniana. Individual potash-rich beds are extensive and consistent in grade and Th ickness. Local th ickening occurs where carnallite is the dominani poiash mineral. Th e preferred ore, sy lviniie, is a clean mixiure of sylvite and haliie. Carnalliie and insolubles are avoided wherever possible because of Their detrimenwl effects on mine stability, grade and refining. Sy lvin ite is exTracted by underground mining or brought TO swjace as brine in solution mining. Poiash is separaiedfrom halite byfloiation or sequential crystallization. The refined produci, potassium chloride, is employed as a fertilizer ingredient as well as in chemical and other industrial capaciiies. The ten poiash mines of Wesiern Canada all are in Saskatchewan and account for aboui 25 per cem of world production. Faciliiies are being expanded, and a new mine and refinery was planned for ihe Breden bury area. Deposiis in Manitoba also were being evaluaied.

Jan 1, 1984

By J. G. Henning

Following completion of planned mining operations at the Goldcorp Dome Open Pit Mine, a high-grade Shaft Pillar located in the pit highwall was recovered. Mining of this Shaft pillar faced numerous rock engineering design and implementation challenges due to its remote position on the highwall and the presence of mine workings within the wall. The case example presented in this paper discusses the geotechnical investigation performed at the site, novel measures undertaken for installation of ground support required for rockmass reinforcement and for worker protection, as well as operational challenges to successful mining of the Shaft Pillar.

May 1, 2009

By P. K. Naik, B. Das

Flotation studies were carried out to recover carbon values from blast furnace flue dust containing ~30.34% carbon, 4.6% volatile matter (VM), and 65.03% ash. The variables chosen for the experiments were dispersant (sodium hexametaphosphate), pH, collector (diesel oil), and frother (MIBC). The experiments were designed according to a 24 full factorial design method and regression equations for the recovery of carbon and product grade were determined from the data. Experiments were performed to optimize recovery and grade using the steepest ascent method. The maximum recovery of carbon was 90.0% with a concentration of 56.5%, whereas the maximum obtainable grade of carbon was 66.35% with 50.45% recovery.

Jan 1, 2005

By E. Esponosa-Gomez, J. A. Finch, A. R. Laplante

"Water quality plays an important role in oxide flotation. The effects on selective flotation of fine (1-16 um) pyrochlore of two types of water used at the Niobec concentrator, potable and plant recycle, were assessed. Several pyrochlore collectors and silicate depressants were tested. Water effects were different for each mineral-reagents) combination. In general plant recycle water decreased selectivity and increased reagent consumption. Interpretation of results is given in terms of electrokinetic effects, hydrolysis of cations, and mineral-collector interactions. Two techniques of treatment for plant recycle water, cation precipitation and zeolite adsorption were assessed. The former was found to be more effective under the tested conditions but recycle water continued to give poorer selectivity than the potable.INTRODUCTIONWater quality plays an important role in selective flotation. Specific effects have been reported by many workers (1-6) and in general the better the water quality the more selective is flotation. Water composition depends on origin and the minerals being processed. For example pulp containing salt-type minerals (calcite, apatite, dolomite) will contain more Ca and Mg cations than that from a sulphide deposit. Another source of water contamination is the flotation reagents added to the pulp, particularly if water recycling is practiced."

Jan 1, 1986