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By K. S. Coley, G. A. Irons, T. Kaneyasu

"It is very important to reveal the lime dissolution mechanism in steelmaking slag, to promote its dissolution without calcium fluoride, which is now almost forbidden for use in most industrialized countries. In this research, the purpose was focused on the development of an experimental method to measure the mutual diffusivity of Ca2+ under the condition of lime dissolution into slag. By forming diffusion couples using a ""vacuum slag aspirating technique"", the method was established. The following mutual diffusivities of Ca2+, in CaO-SiO2-FeO slag systems, imitating oxygen steelmaking slag, were determined using this method:4.1*10-10 m2/s at 1400°C for 27wt.%CaO-53wt.%SiO2-20wt.%FeO slag,4.3* 10-10 m2/s and at 1400°C for 20wt.%CaO-40wt.%SiO2-40wt.%FeO slag, and 1.3*10-10 m2/s at 1250°C for 20wt.%CaO-40wt.%SiO2-40wt.%FeO slag.It was also verified that, if the basicity and ferrite content of the bulk slag are low, then a calcium silicate film forms on the lime surface, and drastically deters the lime dissolution."

Jan 1, 2004

"Pilot plants for pressure hydrometallurgy represent special design and project execution challenges. Over the past twenty years, Zeton has designed and fabricated a variety of world-class pressure hydrometallurgical pilot-plant facilities for the nickel industry, and this paper discusses design considerations and strategies related to such projects. Project execution methods are also discussed, and guidance is given for the selection of materials of construction and for the selection of appropriate pressure and temperature design points for pressure hydrometallurgical pilot equipment. The paper concludes with a discussion of the need for process similarity with future commercial operations and the realities of pilot-scale equipment.INTRODUCTION The process technology developer or owner and the designer/fabricator of a new pilot-plant facility are faced with some difficult technical choices even after the decision to build a dedicated plant has been taken. A pilot-plant project is usually on the critical path of a large commercial project involving investments many multiples greater than the capital cost of the pilot plant. Schedule savings in the design, manufacture, and commissioning of the pilot plant or in a rapid completion of the experimental program can be disproportionately beneficial to the overall development project. However, inappropriate shortcuts resulting in major oversights can be disproportionately problematic. A number of considerations and suggestions for both the project execution approach and the process engineering design of pressure hydrometallurgical pilot-plant facilities are presented as a guide for potential owners and operators of new pilot-plant equipment and facilities. These suggestions are particularly applicable to the nickel industry, where the majority of our firm’s prior hydrometallurgical experience was obtained. This paper is an update to an earlier publication (Martin, 2004), offering an opportunity for a new generation of metallurgists and engineers to learn the specialist requirements of pilot- and demonstration-scale plant design, which are key functions in the development and commercialization of new processes."

Jan 1, 2017

By Alessandro Navarra, Amir Arash Rafiei, Kristian Waters

Mathematical programming (MP) is fundamental to systems engineering and operations management, but has not been widely adopted by mineral processors. The current paper presents an interdisciplinary approach, using MP to incorporate basic notions of mass balancing into an optimization framework. The optimization is typically related to economic profitability. Two- and three-product formulas are extended to give formal descriptions of alternate modes of operation, and a global representation of the concentrator. At this global level, the framework may assist plant managers to make tactical decisions based on incoming feed data. The MP framework is demonstrated through sample calculations describing a lead-zinc concentrator.

Jan 1, 2015

By W. Abdellah

Underground mine developments, such as haulage drifts and cross cuts, play a vital role in providing access to ore extraction areas for mine production. The stability of mine developments is thus of crucial importance during the life of a mine plan. Many Canadian mines use longhole mining methods or one of its variants. These methods require access to the orebody through mine developments such as haulage drifts and cross cuts on multiple levels. This paper examines the stability of mine development access intersections with respect to the planned mining sequence. A case study, the #1 Shear East orebody at Vale?s Garson Mine in Sudbury, Ontario, is presented. A three-dimensional, elastoplastic, finite difference model (FLAC 3D) was created for a development intersection situated 1.5 km below ground surface. The stability, or performance of the intersection, is evaluated in terms of the strength-to-stress ratio. The ratio threshold is set at 1.4 for temporary openings. Unsatisfactory performance is defined as a strength-to-stress ratio less than this threshold value. The performance of the intersection stability is evaluated at various modelled mining stages and the probabilistic method of analysis is then invoked to study the probability of unsatisfactory performance of the intersection. The results are presented and categorized with respect to probability, instability, and mining stage.

Aug 1, 2013

By C. McLachlan, J. R. Donald

"Positioned at the forefront of the seafloor minerals industry, DeepGreen Resources is on track to becoming a leading producer of base and strategic metals obtained from vast high-grade seafloor polymetallic nodule deposits. DeepGreen believes the seafloor minerals industry is an opportunity for developing a more environmentally and societally attractive way to produce cleaner base and strategic metals. Polymetallic nodules contain nickel, manganese, copper, cobalt and other base and strategic metals. Polymetallic nodules represent an exceptional multi-metal-bearing resource, and no current metallurgical operation or flowsheet exists that can recover the primary metallic values while managing the distinct mineralogy. DeepGreen Resources is developing a new process to maximize the business outcomes consistent with the highest environmental standards, including targeting a near zero waste facility. The present paper discusses the history, context and driving forces of polymetallic nodule project development. An overview of DeepGreen?s Nauru Ocean Resources Inc. (NORI) project is presented along with a literature review of polymetallic nodule processing and the on-shore project development scope and plan at DeepGreen Resources is outlined.INTRODUCTION AND CONTEXT Polymetallic Nodules in the Clarion-Clipperton Zone Containing nickel, cobalt, copper and manganese, polymetallic nodules occur in most oceans of the world. The nodules lie on the seafloor sediment. The largest deposit in terms of nodule abundance and metal concentration occurs in the Clarion-Clipperton Zone (CCZ) on vast abyssal plains at a depth of 4,000 to 6,000 metres. The CCZ is located almost entirely in international waters as presented in Figure 1. It has been estimated that the CCZ contains (International Seabed Authority, 2010): •,>21 billion tonnes of nodules; •,>270 million tonnes of nickel; •,>6 billion tonnes of manganese; •,>234 million tonnes of copper; •,>46 million tonnes of cobalt. There are several active hypotheses for the mechanism of formation of the nodules including precipitation, hydrothermal decomposition of basaltic debris, and involvement of microorganisms. Nodules require a nucleus to start forming, which could be a piece of pumice, a shark tooth, old nodule piece, basalt debris or even microfossils like radiolaria and foraminifera. Nodules form concentrically with layers of iron and manganese hydroxides around a core. Although composed mainly of Mn, Fe, silicates and hydroxides, it is the significant content of Ni, Cu, Co, Zn and Rare Earth Elements (REE) that is generating the economic interest in harvesting these deposits. Nodules vary in size from micro-nodules to about 20 cm, the common size being two to eight centimeters. A typical polymetallic nodule and polished cross-section is presented in Figure 2."

Jan 1, 2017

By A. Makinen

There is an increasing trend between increasing consumption of water and the production of metal concentrate. Along with this trend we see that ore grades are declining and getting more complex to concentrate around the world. This will not only complicate processing but also generate new requirements for the management of water and waste streams on mining sites. The mining industry is a large user of water and its water consumption is growing rapidly. The processing of lower quality ores requires greater volumes of water. For these reasons, the need for efficient use of water and water management at mine sites is becoming more urgent. The perception of water in the mining industry has changed from thinking about it only in terms of "water treatment" to actually seeing it as a valuable resource, a resource that needs proper management. This resource management needs to involve various aspects, such as optimizing water usage of the entire mine or concentrator site, minimizing fresh water usage, minimizing or eliminating waste generated in water treatment and implementing practices for water reuse and water recycling. This paper presents trends and new developments relating to waste and water management in the mining industry.

Jan 1, 2015

By K. Webb

At both the international and country level, the issue of how the mining sector and indigenous populations should engage on issues of mutual interest or concern has emerged as one of central importance and controversy; involving the mining industry, Aboriginal communities, governments, the courts, and other stakeholders. At its heart, stakeholder engagement is an ethical issue, although it manifests itself in international instruments, domestic laws, industry guidance and agreements. At the international level, the concept of ?free, prior and informed consent? (FPIC), while not subject to widespread agreement on the finer details of evolving definitions, seems to be emerging as an increasingly recognized engagement norm. Within Canada, through a series of decisions, the Supreme Court of Canada (SCC) has articulated a fiduciary obligation of the Crown to consult with and accommodate impacted Aboriginal groups on resource management issues. Provincial governments have been variously attempting to adjust their resource management regimes to stay in alignment with SCC and lower court decisions. Mining sector organizations, working with First Nations partners, have developed agreements to work together for mutual benefit. At the individual mine and community level, there have been instances of constructive engagement, as well situations of physical resistance and legal challenges. The purpose of this paper is to examine the potential impact of new rules under the Ontario Mining Act introduced in 2012 and taking full effect in 2013, which amongst other procedural specifications, addresses the issue of mining industry-Aboriginal consultation in exploration and development activities. Leading up to the passage of the regulations, representatives from some junior mineral exploration companies have been highly critical of the new rules. Similarly, there have been a range of responses to the new rules from some in the First Nations community. The paper will review the regulation in terms of its apparent alignment with SCC decisions and the international norm, compare the regulations with existing mining sector organization guidance documents, and it will draw on the stated perspectives and commentaries of First Nations communities, mining firms, governments, nongovernmental organizations, and others. Building on the foregoing, the paper will provide a preliminary analysis of the perspectives and potential impacts of the new regulation on various stakeholders, and on that basis, possible avenues for further consideration will be suggested.

Aug 1, 2013

By P. L. Lehoux, R. F. Lopes

"Unanticipated low recovery or extraction of gold from heap leachable are can often be attributed 10 phenomena such as non-uniform percolation (channelling) of solution through heaps, excessively slow percolation rates due to densification of ore during stacking on the pads and parasitic or competing reactions of the cyanide solution with undesirable elements or geochemical ""impurities"" in the ore. The nature and causes of these phenomena are discussed in this paper, and it is suggested that geotechnical and geochemical expertise can contribute significantly to a better understanding of the relationship between laboratory results and actual field performance of the leaching process. Recommendations are made for bench-scale metallurgical testing to be complemented by geochemical and geotechnical laboratory evaluations, to ensure more successful heap leach projects. IntroductionHeap leaching is a simple, low-cost method of recovering metals from low grade ores which has now come into widespread application particularly for gold and silver metals in the United States.The heap leach process involves percolating a lixiviant (leaching agent) solution through broken or crushed ore (Chamberlain and Pojar, 1984). In the case of gold a dilute sodium cyanide solution is used and crushed ore is ""heaped"" on specially prepared impervious pads.The potential for use of heaping leaching methods for northwestern Ontario gold deposits was discussed by Beard (1983), who suggested that the use of this extraction technique in Canada should grow significantly for low grade ores as well as for small high grade deposits which cannot justify the installation of a new mill or the use of remote custom milling facilities. Two other potential situations for lise of a heap leaching extraction method are : as a low capital cost cash generator in the opening phase of a larger new project, and as a low cost output augmenter to complement a milling operation."

Jan 1, 1989

By Christiaan Zeilstra, Jan van der Stel, Koen Meijer, Gerard Louwerse, Tim Peeters

The steel industry is producing about 5% of the world wide CO2 emission. Therefore the European steel industry has defined a research program to reduce the CO2 emission by 50% per ton: ULCOS. Since its start in 2004 ULCOS has identified four technologies for further development. Two of these technologies which produce liquid hot metal are discussed. The ULCOS blast furnace is based on recycling of decarbonated topgas and the capture and storage of CO2. The concept has been demonstrated during three campaigns at LKAB EBF in Luleå, Sweden. The smelting reduction process HIsarna is a combination of the cyclone-technology and Hismelt. The process has been demonstrated successfully in four campaigns at a pilot installation on the IJmuiden steelmaking site.

Jan 1, 2015

"Cambior currently has nearly 80 exploration properties, acting as operator on about 60 of these. The company's exploration budget has increased to over $11,100,000 for 1990. On-going efforts recently yielded a new gold discovery on the Douay- Vezza property, a joint venture project with Inco and Vior. Cambior continues to seek out new opportunities, recently acquiring an option agreement on the Sleeping Giant project in Quebec and four new exploration agreements in the United States, through its Reno office. Other nearly-concluded joint venture agreements have also given the company entries into Indonesia and Guyana.SummaryWhen it acquired SOQUEM's assets on August I, 1986, Cambior also acquired interests in 45 exploration projects. The subsequent mergers with Aiguebelle Resources and Sullivan Mines in 1987 brought the total number of exploration projects to 83, most of which are concentrated in northwestern Quebec. Cambior's strategy emphasizes gold exploration, and exploration activities were, therefore, initially limited to the Val d'Or and Rouyn-Noranda mining camps, where Cambior has a large portfolio of properties. Approximately $25.8 million has been spent on surface exploration in this area since the formation of the company, resulting in the discovery of the Mouska deposit and four sub-economic zones on the Porcupine, Forbex, Bloc Sud and Flavrian project s. In 1988, Cambior became involved in projects in the United States to which the company expects to allocate about 38070 of its 1989 exploration budget."

Jan 1, 1990

This paper focuses on the dissolution of various Manganese based compact additions into liquid Magnesium. The experimental procedure employed cylindrical compacts with various Manganese compositions. The various temperatures of the additions and the Magnesium bath were measured simultaneously during the immersion of the additions into Magnesium bath. The exothermicity level of these additions during their dissolution into liquid Magnesium was determined. The relation of the exothermicity level with the dissolution kinetics was also examined. In addition, SEM and EDX work was conducted for additions, which were withdrawn from the Magnesium bath. Finally, the recovery of these additions was estimated by taking samples from the Magnesium bath and conducting ICP analyses.

Jan 1, 2006

By S. Fox, Y. Fujita

Increasing demand for rare earth elements (REE) is expected to lead to new development and expansion in industries processing and or recycling REE. For some industrial operators, sending aqueous waste streams to a municipal wastewater treatment plant, or publicly owned treatment works (POTW), may be a cost effective disposal option. However, wastewaters that adversely affect the performance of biological wastewater treatment at the POTW will not be accepted. The objective of our research is to assess the effects of wastewaters that might be generated by new rare earth element (REE) beneficiation or recycling processes on biological wastewater treatment systems. We have been investigating the impact of yttrium and europium on the biological activity of activated sludge collected from an operating municipal wastewater treatment plant. We have also examined the effect of an organic complexant that is commonly used in REE extraction and separations; similar compounds may be a component of newly developed REE recycling processes. Our preliminary results indicate that in the presence of Eu, respiration rates for the activated sludge decrease relative to the no-Eu controls, at Eu concentrations ranging from <10 to 660 µM. Yttrium appears to inhibit respiration as well, although negative impacts have been observed only at the highest Y amendment level tested (660 µM). The organic complexant appears to have a negative impact on activated sludge activity as well, although results are variable. Ultimately the intent of this research is to help REE industries to develop environmentally friendly and economically sustainable beneficiation and recycling processes.

Jan 1, 2016

M INE production requires the coordination of the talents of men and the use of equipment. Mine operators maintain a continual surveillance of equipment, looking for improvements and modifications that will benefit them. Few give similar attention to the advances made in the education of mining engineers since they themselves graduated. That is not surprising. Education lacks the advertising budget available to manufacturers. A modification to improve a mechanical contrivance is advertised, and an advertiser&apos;s press releases get attention by publishers. The whole program for mining engineering education could be revolutionized and no one, except a few professors, would know about it. The Canadian Institute of Mining and Metallurgy&apos;s newly established General Commit-tee on Education can improve that situation. Nine groups of engineers in Canadian universities are trying to give undergraduates an education that will make them useful to the mineral industry as mining engineers. The tabulation offered here (Table I) is an analysis of the distribution of the undergraduate-teacher contact time.

Jan 1, 1963

By Richard Cyr, Peter Larsen, William Quesnel

"The need to continually improve efficiency and lower costs in mining operations is of paramount importance to all concerned in the industry. Mining operations are constantly testing new methods and equipment in order to lower costs and improve productivity. Equipment suppliers strive to fulfill the demands of the mines through improved design and innovative ideas for productivity increases. In some cases, however, an increase in productivity does not require new equipment design, but rather the application of an existing mining method into different operating parameters. Such is the case in applying longhole methods to narrow vein ore deposits.Bulk mining methods have long been recognized as efficient, low-cost alternatives in narrow vein operations. Typically, shrinkage and some cut-and-fill methods are employed. The shortfall of these methods is the tendency to be labour intensive. The demand for miners skilled in these methods far outweighs their availability. Consequently, labour-efficient methods have to be employed to fill the void. The application of longhole drilling techniques to narrow vein deposits is one such method.IntroductionPercussion longhole drilling evolved in Canada in the early 1940s. Prior to percussion drilling, blast holes were drilled using diamond drill equipment. Jack Gardner, of Gardner Steel, began testing with carbide percussion bits and extension drill steel in applications where diamond drills had been previously employed. Percussion drilling equipment proved to be considerably more productive and cost-efficient. The experiment eventually led to the replacement of diamond drills in this application.Over the years, the percussion methods were improved, with particular emphasis on the equipment used. Rifle bar rotation machines evolved to independent rotation. Bar and arm set ups evolved into self-contained mobile drill carriers that increased productivity while reducing the physical labour. The introduction of hydraulics further improved efficiency and production figures. Today, it is not uncommon to see fully computerized jumbos in production longhole drilling applications. These machines represent the ""state-of-the-art"" in longhole drilling equipment.Production longhole drilling is considered to be one of the most efficient bulk mining methods in use today. Production statistics normally exhibit low-cost, efficient ore extraction. As a rule, longhole (blasthole) methods are associated with substantial ore deposits. These methods have exhibited high production figures and low mining costs.Over the past decade, long hole methods have been applied to several narrow vein deposits. These applications have proven that, given the right parameters, longhole methods will produce the same advantages in narrow vein deposits as are seen in more conventional applications."

Jan 1, 1990

By Geo. E. Cole

A GREAT deal of time and energy is now being devoted to the study of post-war reconstruction and rehabilitation, in spite of the fact that as yet we have not won the war in which we are presently engaged. If you feel that the study of post-war problems takes our thought away from the problem immediately before us, you may well query, "Well! What has all that to do with winning the war, our most urgent problem today?" The answer has been given by Principal James of McGill University, Chairman of the Cabinet Committee on Reconstruction: "Reconstruction is something which must be thought of in advance, partly for the purpose of recognizing exactly the influence of war-time activities, controls, and regulations on the post-war Canadian scene. Many people are acutely interested in this great problem. It is not that they are not interested in the war itself, or epochal events that are taking place from day to day. They have a vision of that future which they hope will be Canada&apos;s, and this vision inspires them to even greater efforts at the present time". The trend of events would indicate that changes, economic and industrial, after this war will be greatly out of line with those that followed previous wars in history, for the present struggle has involved every nation in the world. In the peace that will come, every engineer will have a task in bringing the most desirable order out of the most distressing chaos. We certainly are living in a changing world; we are witnessing geo-graphical and economic readjustments that no other generation in world&apos;s history has ever witnessed. And there is an opinion gaining strength in our Dominion, as in other lands, that after this war we shall live in a world in which our process of thinking and our very way of life will have to undergo drastic changes to cope with the new order of things. Sadly our world of today has had to revise the sublime vision that nation shall not lift up sword against nation, while salvage operations continue to beat ploughshares into tanks and the peaceful pruning-hook into a weapon for the deviltry of the commando.

Jan 1, 1943

By M. Gauthier, A. C. Brown

"Monometallic zinc mineralization associated with marbles of the Grenville Supergroup in the Mont-Laurier Basin of Quebec is found to be stratiform and to occur (1) within limited zones of dolomitic marble and (2) more precisely along contacts between these marbles and adjacent metaclastic units. Massive sphalerite with accompanying pyrrhotite and pyrite is the prime exploration target, and commonly gives rise to good geochemical anomalies, but generally weak and ambiguous geophysical responses. Disseminated sphalerite in dolomitic marbles may signal proximity to interesting massive mineralization, although, due to weathering, this broadly disseminated mineralization may not be detected easily on outcrops. It is concluded that the western and possibly the eastern margin of the Mont-Laurier Basin constitute favourable areas for continued exploration.IntroductionThe Grenville Supergroup marbles of Ontario, Quebec and New York State host numerous occurrences of zinc mineralization (Fig. I) , several of which have been periodically mined since the beginning of this century (Fig. 2). The Balmat Edwards district of New York is the giant of this depo sit-type, with the production since 1915 of some 20 million tons of ore grading 10% zinc, and acknowledged current reserves of approximately equal tonnage and grade. At present, there is renewed interest in the potential for similar mineralization throughout the Grenville Supergroup, and this paper outlines some of the geological, geochemical and geophysical guidelines that may be employed in the search for new ore. The geologic guidelines are derived especially from lithologic and stratigraphic features which survived intense, multiphase deformation and metamorphism.Although major portions of the extensive Grenville Supergroup hold potential for zinc mineralization, the present study is confined to a known zone of mineralization in the Mont-Laurier Basin of Quebec. Concurrently, we are compiling information on the regional metallogeny of the basin so that our conclusions can be applied to areas of similar Grenville Supergroup host-rocks elsewhere."

Jan 1, 1980

By Eric Best

"In the past two to three years, all continuous mining machines at the Potash Corporation of Saskatchewan Mining Limited, Lanigan Division, have been changed over to a new cutting pattern using 1 -inch- and 1-3/l6-inch-diameter self-sharpening pencil bits. The bits are arranged in a cone-type pattern across the face on 2 1/2 -inch and 3-inch spacing. The result is that the ore is removed by chipping and flaking. Previously, rap-lock bits were used, with the pattern being several bits in single rows at wide spacings. The cutting action was grinding and breaking.Besides improved penetration rates and lower bit costs, there are many other advantages. The ore size is much smaller, resulting in less wear and tear on conveyors and other associated equipment. Feeder-breakers are no longer routinely set up at the head end of every extensible belt, as the banana-shaped chunks of ore that used to require breaking are no longer produced. Also, less dust is generated by the cutting heads and fewer stops are required for bit changes. Even the mill operation has been improved, as fewer fines are produced.Further improvements are still sought after, but, all in all, the new cutting pattern is considered to be a giant step forward from the old method."

Jan 1, 1981

By Stuart McTavish

"The Brunswick Mining concentrator processes 10,000 D.S. T. per day of a complex sulphide ore. Four separate concentrates- zinc, lead, copper and bulk-are produced by selective flotation. Several major changes have been made to the Brunswick flotation circuit to improve the process and control. This paper will describe the present flotation practices at the Brunswick Concentrator. Special emphasis is given to the conversion of two of the primary circuits to an SO2-aeration flowsheet, and to the addition of a new secondary zinc flotation circuit that produces a zinc concentrate from the plant tailings. IntroductionBrunswick Mining and Smelting Corporation operates a zinclead- copper and silver mine and concentrator near Bathurst, New Brunswick. Since the start-up of operations in 1964, the flotation flowsheet has undergone major modifications to process the increased tonnages and to produce a greater number of concentrates. The flowsheet for the concentrator as it was in 1971 has been described by Neumann and Schnarru) and by Ersklneco. Since then, in 1971, the No.6 concentrator was converted from bulk flotation to selective flotation to produce a copper, lead and zinc concentrate. A separate zinc upgrading circuit was installed in 1972 and a bulk flotation or dezincing circuit, which reduced the zinc in the lead concentrate, was started in 1973. In 1976, the secondary zinc circuit was initiated.In addition to these new circuits, changes have been made to the existing circuits to simplify their operation."

Jan 1, 1980

By D. C. Fraser

"Geophysical Engineering and Surveys Limited of the Keevil Mining Group have routinely conducted ground surveys with VLF-EM receivers for the past two years. Both Crone's Radem and Ronka's EM16 have been used.VLF-EM dip-angle data often yield complex patterns which require considerable study for a proper interpretation. A method was developed which allows field operators to transform the noncontourable dip angles into contourable data, producing conductor patterns which are immediately apparent to exploration personnel untrained in VLF-EM interpretation.VLF-EM contoured data generally peak very close to the top of a conductor, thereby allowing drill holes to be spotted accurately. However, the data generally should not be used alone to select drill targets because structures may be sufficiently conductive to yield strong anomalies. Thus, magnetic and/or vertical-loop EM correlations may be considered as necessary criteria for drilling.VLF-EM surveys can replace IP surveys in certain environments. For example, the Restigouche orebody in the Bathurst camp of New Brunswick yielded a VLF-EM anomaly as distinct as that obtained by IP, although the body did not respond to vertical-or horizontal-loop EM. However, the cupriferous breccia pipes of the Triba mine near Batchawana, Ontario yield strong IP anomalies but not VLF-EM anomalies, illustrating that disseminated ore targets should be sought with IP rather than with VLF-EM."

Jan 1, 1971

By Bahri Öteyaka, Ali Uçar, Oktay Sahbaz

"A Jet Diffuser Flotation Column (JDFC) is a newcomer flotation device whose operation principles similar with Jameson cell but it has an essential change in downcomer. By taking into account the hydrodynamic and fluid mechanic principles (Sahbaz et al. 2013) downcomer was changed as a diffuser, therefore turbulence at the end of the downcomer was reduced to provide better aggregate stability and homogenous dissipation of the bubbles in the separation tank. Thus the performance increase has been aimed for the coarse particles.According to theoretical results, obtained by the formula of Oteyaka (1993) showing the relationship between velocity gradient and maximum floatable size for the various contact angles, the d50 of quartz flotation of JFDC is about 240 µm and 310 µm for the contact angle of 50° and 60°, respectively. This result was verified by the experiments. According to the experimental results; d50 which was accepted the maximum floatable particle size of quartz flotation of JFDC was about 256 µm and 300 µm for the contact angle of 50° and 60°, respectively.INTRODUCTIONFlotation is a kinetic process used for separation of hydrophobic particles from hydrophilic particles. There are many different parameters affects the success of the flotation and particle size is one of them. While the flotation is very efficient for intermediate size, the efficiency of the process starts to decrease for both fine and coarse sizes (Trahar, 1981; Muganda et al., 2011). Therefore; researchers have tried to find a solution for the efficiency decrease in fine and coarse sizes by modifying the chemical condition and designing the new devices. For example, Jameson cell is a unique device for the fine particle flotation due to the suitable design and fine bubble producing (Jameson, 1988; Evans et al., 1995; Sahbaz, 2010). Because of this success operation the Jameson cell is applied more than 200 flotation plants in worldwide. On the contrary, the efficiency of the cell decreases for coarse particle flotation due to the turbulence occurred in the separation tank (Sahbaz, 2010; Cowburn et al., 2007). That’s why, new flotation device was designed in loboratory scale by Sahbaz, Oteyaka and Ucar in 2010s and it has been called as Jet Diffuser Flotation Column (JDFC) recently."

Jan 1, 2016