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By S. Chander

A series of nonionic and anionic surfactants were tested to enhance the flotation response of a low rank coal. An ethoxylated octyl phenol and several polypropylene polyethylene block copolymers were tested as nonionic surfactants. The anionic surfactant was a dioctyl sulfosuccinate. All the surfactants employed improved the yield significantly but the influence on grade was complex. Separate studies were conducted to determine the emulsification behavior of the surfactants. For the nonionic water soluble reagents tested, a correlation between emulsifying power of the surfactant and flotation was observed. An increase in the number of droplets produced in surfactant containing systems was considered to be the main reason for increase in the yield. Since it increased the number of collisions between dodecane droplets and coal particles. When a surfactant was introduced into the flotation pulp prior to addition of dodecane, it decreased the benefits of the surfactant significantly. The decrease was attributed to an increase in the wettability of coal and a decrease in the surfactant available for emulsification. When a suitable surfactant was added as a solution dissolved in the oily collector, a considerable increase in yield was observed.

Jan 1, 1993

By M R. Drumond

The present work presents a new theoretical interpretation of the flotation process, which can also be applied to other mineral processing physical unit operations. This interpretation is part of the æModelo OperacionalÆ (Operational Model) that was developed as an attempt to establish a new theoretical basis for mineral processing unit operations. In the case of flotation, a book was edited by one of the authors in Brazil (Mass Concentration by Froth Flotation, in Portuguese and Spanish).The model establishes a link between a natural phenomenon (migration of particles from the pulp to the froth) and a real industrial phenomenon (mass concentration by operational interference). In this model, flotation is viewed as a phenomenon of macromolecular mass transport (of particles) between froth and slurry phases. Mechanisms for mass transport and particle flow between phases as a function of the hydrophobic potential in each phase are discussed. By establishing the so-called equilibrium distribution curve between phases it is possible to calculate macroscopic balances that are related to metallurgical results, which in turn are a function of the operational line that is required by the process itself. The number of cleaning stages and their efficiencies can also be determined by simple laboratory-scale experiments.

Jan 1, 2005

By M. Tarvainen, J. Kallioinen

"Depressed metal prices coupled with increasing production costs have presented a great challenge for operators to control and reduce the costs of production to maintain profitability. Depleting ore reserves, added to the above has forced Outokumpu to take a hard look at its operations, to develop new methods to profitably extend the life of its mines. One of the areas investigated and approved for further development has been the use of larger and more energy efficient equipment. As a result, large flotation machines were developed and today 38 and 60m3 flotation machines are in use.Secondly, ore preconcentration has been developed to avoid processing the part of the ore that has little or no mineral values.Another quite recent development and the topic of this paper, has been the use of coarse flotation before conventional flotation. The main idea is that part of the valuable mineral is separated as early as practical by floating it with specially designed flotation equipment, installed in the grinding classification circuit. The new flotation cell is specially designed for this application and differs from the conventional cells in the tank design, feed arrangement and modified mechanisms in some cases."

Jan 1, 1984

By S. N. Opperman

Testwork at Goedehoop Colliery showed that fine coal, essentially?150 microns can be successfully beneficiated using froth flotation. Both conventional and column flotation were tested. It was found that the traditional stirred tank type of flotation machines used in conventional flotation produced the best recovery of fine coal. After extensive testwork it was decided to develop a flotation machine on Goedehoop Colliery that would combine stirred tank and quiescent column technology. It was thought that this design would give the best combination of recovery and selectivity. The Multicell was developed and is producing results acceptable for Witbank coal flotation. Keywords: Multicell, Witbank coal flotation, froth, stirred tank, quiescent column.

Jan 1, 2002

By Adam Wright

"Les Mines Selbaie have been producing copper and zinc concentrates from the A-1 ore zone since 1986. This paper reviews major developments in flotation practice over that period. Firstly, ore blending strategies for Selbaie's non-homogeneous polymetallic ore are discussed. The evolution of reagent use is then reviewed, focussing on copper collector trials. A description of Selbaie's flotation columns follows. Finally, past and future developments for process control are outlined.Depuis 1986, Les Mines Selbaie produisent du concentré de cuivre et de zinc provenant de la zone A-1. Cette conférence présente !es développements majeurs en flottation qui ont eu lieu depuis ce temps. Premièrement, la stratégie du mélange de minerai non homogène polymétallique est présentée. L'évolution des réactifs utilises est démontrée, particulièrement !es collecteurs de cuivre. Par la suite !es colonnes de flottation sont presénteés et finalement !es développements futurs ainsi que ceux qui ont eu lieu dans le contrille de procédé sont expliqués.1.0 INTRODUCTIONLes Mines Selbaie, wholly owned by Billiton Metals Canada Inc., is currently mining and processing ore from a polymetallic surface deposit located 288 km northwest of Val D'or, Quebec (fig. 1). The mine produces copper concentrates containing gold and silver as well as zinc concentrates containing silver. 8000 dmt/day of ore is crushed and ground to 80% passing 49 µm, prior to processing by conventional copper/zinc differential flotation. The flotation circuits consist of both conventional and column cells (fig. 2). Detailed descriptions of the mill are available elsewhere in the literature (8,9)."

Jan 1, 1995

By J. E. Gebhardt, D. W. Fuerstenau

The use of small quantities of polyacrylic acid (PAA) was found to significantly improve the flotation of fine-sized hematite particles at pH 4.1 and 0.001 M NaCl with sodium dodecykulfonate (SDS). Low polymer dosages before collector addition aid flotation by forming flocs of primary particles, but excess polymer results in low flotation yields due to surface saturation by the hydrophilic polymer. Contact angles, measured on a hematite disk, substantiate the hydrophilic nature of an adsorbed polymer film. Pre-adsorbed PAA reduces the amount of SDS adsorbed on the hematite particles, but the flotation of hematite flocs occurs, even at reduced amounts of adsorbed SDS, and is not depressed until PAA dosages in excess of the saturation value are used. Separation of a hematite-quartz mixture can be achieved by SDS flotation of PAA,-flocculated hematite. Maximum selectivity results with the addition of small quantities of PAA, while excess polymer is detrimental to the recovery of hematite. Consecutive flotation states on a single feed yield a higher grade hematite product at some expense to the overall recovery.

Jan 1, 1987

By Manlapig E. V

ABSTRACT- I Results are given for a series of tests in which a 300 mm pilot-scale Jameson cell has been used in copper recleaner flotation, and for the flotation of a lead rougher feed. the results indicate that the production rate of solids, at the same superficial air velocity Jg, is higher than in conventional columns. Thus in the copper recleaner application, the pulling rate reached 14 gm/cm2/min compared with between two and three for an operating column, while in the lead cleaner application the comparable figures were 12 - 14 gm/cm2/min for the Jameson cell vs 8 - 9 gm/cm2/min for a test column. A froth crowder was used to increase the air superficial velocity Jg in the Jameson cell in the copper recleaner, while holding the collection mechanism and pulp feed rates constant. The recovery increased from 50 per cent to over 90 per cent, suggesting that recovery is controlled mainly by the froth conditions, rather than the particle-bubble interactions in the Downcomer.

Jan 1, 1991

By G J JAMESON

The flotation cell has undergone a number of changes since the process was first introduced in Broken Hill in the early years of this century. The development of the mechanical flotation cell is reviewed, followed by a discussion of more recent developments such as the flotation column, the air-sparged hydrocyclone, the Wemco-Leeds cell, the Bahr and Deister columns and the Jameson cell.

Jan 1, 1992

By Young Hyun Paik, Hyung Sup Choi, Yeun Sik Kim

The basic studies on the surface properties and flotation characteristics of ilmenite were made by electrophoretic, adsorption, contact-angle and floatability measurements. The isoelectric point of ilmenite is found to be at pH 5.6. By combining the results of electrokinetic studies and adsorption measurements, a clearer picture of the ilmenite-solution interface was observed. These findings were correlated with the floatability of ilmenite obtained by Hallimond tube tests. The general flotation characteristics of ilmenite are compared with those obtained for magnetite and rutile. It is indicated that the above three minerals, namely, ilmenite, magnetite and rutile, have very similar surface properties and flotation characteristics. Therefore, it is difficult to make an effective separation of these minerals by flotation. However, it is found that sodium orthophosphate acts as a selective depressant for magnetite in anionic flotation. Therefore, close pH control of the pulp in the presence of the phosphate ion enhances the possibility for a successful separation of these minerals.

Jan 1, 1967

By S. G. Dixit

Alunite (KAl3(SO4)2(OH)6] is one of the important nonbauxitic resources for aluminum in U.S.A. The major gangue material associated with a unite ore body is quartz. Experimental results indicate that oleic acid flotation of alunite is quite effective in upgrading the ore. The flotation chemistry of the alunite/oleate system has been investigated using various techniques such as: hallimond tube flotation response, measurement of adsorption density using I4C labeled oleated, electrokinetic measurements, infrared spectral studies, contact angle measurements and thermochemical measurements using an isothermal microcalorimeter. Alunite has been found to float readily with oleate in the pH range 4-10.5 and its flotation response is enhanced at higher temperatures. The PZC of alunite has been determined to be at pH 7.2 ± 0.15 which agrees with what would be predicted from solution chemistry and from the flotation response with physically adsorbed collectors. Infrared spectra show a specific peak in the range 1585-1600 cm-1 which has been attributed to the formation of an aluminum oleate surface species. Both adsorption density measurements and infrared spectra indicate that during adsorption multilayers are formed. The heat of adsorption of oleate on alunite has been found to be endothermic and of the order of 4-6 KJ/ mole.

Jan 1, 1980

By M. S. Celik, H. Du, J. D. Miller, F. Cheng, O. Ozdemir

"In this paper, recent progress with respect to the flotation chemistry of soluble salt minerals is reviewed, and some of the more relevant issues including the hydration states of ions, the interfacial phenomena of salt surfaces and the flotation behavior of selected soluble salts are discussed. Due to the high solubility, the flotation of most soluble salts has to be carried out in their saturated brines. Anecdotal evidence has suggested that the hydration states of the ions have significant influence on the physicochemical properties of the solutions, the surface charge and wetting characteristics of the minerals, the collector adsorption states and, further, the flotation behavior of the soluble salts. In this regard, reviewing past research findings, efforts are made to establish a correlation between the ion hydration states with the flotation behavior of the soluble salts. Further, advances in understanding the significance of colloid adsorption involved in the soluble salt flotation process are addressed, and future research efforts to understand the soluble salt flotation chemistry are suggested.IntroductionSoluble salt minerals are essential raw materials for the production of a variety of commodities, fertilizers, potassium hydroxide, soda ash, magnesium compounds and other chemicals. These soluble mineral resources can be processed using flotation technology and, currently, more than 80% percent of the world’s potash is produced by the selective flotation of KCl crystals (sylvite) from other salt crystals, predominately NaCl (halite) and other more complex salts (Searls, 1990). Despite the successful application of flotation technology in the potash industry, the mechanisms for collector adsorption on soluble salts have not yet been fully understood and, therefore, have been of considerable interest to flotation researchers for many decades."

Jan 1, 2015

By J de Cuyper, N. R. Tipman, G. E. Agar, L. Laré, W. Freyberger

The flotation chemistry of the commercial INCO matte separation process was investigated. The slow cooling of Bessemer converter matte forms discrete phases of Cu2S and Ni3S2 and a Cu-Ni alloy. After magnetically removing the alloy, the Cu2S and Ni3S2 are separated by flotation at pH 12.4 (saturated lime) using diphenyl guanidine (DPG) as both collector and frother. DPG has been used exclusively in this flotation process because of its unusual selectivity for copper minerals. The surface product resulting from chemisorption of DPG onto the Cu2S was identified as the double salt Cu(DPG)2SO4,.CU(DPG)2(OH)2. The adsorption followed Langmuir behaviour up to a monolayer coverage. In the absence of DPG, the rapid adsorption of oxygen by Cu2S in flotation pulps was observed. The surface product was identified as the insoluble basic copper sulfate CuSO4.3Cu(OH)2 with the production of sulfate ion. In the presence of DPG, the oxidation reaction appears to be suppressed. The frothing properties of DPG and commercial frothers were compared. DPG is not a powerful frother. Batch flotation tests confirmed that DPG is a highly selective collector when compared to most sulfhydryl collectors.

Jan 1, 1976

By P Wigley

New methods of analysing and modelling flotation circuits have been developed as part of the AMIRA P9 mineral processing research project. A study using these techniques was conducted on the Olympic Dam copper flotation circuit to provide the following outcomes: an estimate of the flotation cell hydrodynamic properties and froth performance characteristics, and identification of potential areas for improvement; an estimate of the feed floatability parameters for basic model development; and identification of potential flotation circuit improvement opportunities. A flotation circuit model of the Olympic Dam copper concentrator was developed using the data collected from mass balanced site surveys, along with hydrodynamic data, froth performance data and numerous laboratory batch flotation tests. The simulator that has been developed from the model has the ability to estimate the influence of selected changes (such as circuit changes) on flotation circuit performance. Several stream destination simulations were conducted to provide guidance for further testwork and possible circuit improvements. The results from these simulations are presented.

Jan 1, 2003

By Dan Alexander, Ivan Crnkovic, Sarah Schwarz

"Several plant studies have been conducted at the Zinifex Century Mine over the past 5 years. For each of the plant studies, surveys of the zinc primary circuit were conducted, characterisation measurements for each operating cell taken, and the floatability components of the ore mapped to develop a model of the circuit. The floatability components and machine parameters were then used to simulate changes in circuit configuration and operating conditions, enabling further potential improvements in circuit performance to be identified.This paper reviews the current flotation practice at the mine, as well as various circuit changes and developments implemented by site. The application of the methodology and the evolution of the standard procedure are also discussed.INTRODUCTIONBase metals were first discovered in the Lawn Hill region of Queensland’s North West in 1869 and the first mining lease in this area was pegged in 1887 over what is now known as the Silver King vein deposit. The area encompassing these veins, which includes the Century deposit, was proclaimed the Burketown Mining Field in 1899. Exploration titles were granted to CRA in 1987, precisely 100 years after the initial discovery at Silver King, hence the name ‘Century’.Century was commissioned by Pasminco in late 1999, with the mine becoming fully operational on 1 March 2000 and the official opening taking place in April. Pasminco had bought the Century and Dugald River deposits from CRA in 1997 for A$345 million, and invested some A$710 million in bringing Century into production. Today, Century is the world’s second-largest zinc mine in terms of its output, having reached full capacity in 2003.The Zinifex Century Limited (“ZCL”) lead-zinc-silver deposit is located approximately 250 kms north-north west of Mt Isa in north-western Queensland. The deposit is a large flat-lying ore body covering an area of some 1.2 by 1.4 km, the 45 m-thick stratabound sulphide orebody is hosted within an 850 m-thick sequence of Proterozoic siltstone, shales and sandstone, amenable to open-cut mining methods. The mine has ramped up to full production delivering five and a half million tonnes of ore per annum, yielding approximately 900,000 tonnes of zinc concentrate and 90,000 tonnes of lead concentrate. Mine life is expected to be about 8 years"

Jan 1, 2008

By Dave Bulled

"This paper describes the design of a molybdenite flotation circuit using FLEET technology applied to kinetics data produced from laboratory flotation testing and distributed across the blocks of a mine plan using a geostatistical approach. The geostatistics assigned the statistical error that arises from having a limited amount of sample testing data to the kinetics estimates of each block of ore in the mine plan. The final design then included a quantification of risk based on the accuracy of the block flotation kinetics and model fitting. The design made reference to the extensive technical reports describing earlier metallurgical test work including some pilot plant work over thirty years ago.The testing involved conducting MinnovEX Flotation Tests (MFT) to determine the rougher flotation kinetics at the specified reagent conditions and rougher-cleaner tests to determine the change in kinetics resulting from regrind. These flotation kinetics were used within FLEET simulations to create a full-scale flowsheet and plant design including recommended equipment sizes and the forecast of operating results. Measurement of detailed flotation kinetics for a wide range of samples allowed the effect of size of grind and efficiency of classification (i.e. width of size distribution) to be predicted for the whole ore body.INTRODUCTIONAdanac Moly Corp. proposed to develop a 20,000 ton per day mill to produce high quality molybdenite concentrate from its Ruby Creek resource in north-western British Columbia. It is a relatively clean low grade porphyry-monzonite occurrence containing minimal quantities of other sulphides such as chalcopyrite, pyrite, sphalerite and galena. Molybdenite occurs mainly as coarse flakes with lesser amounts of finer sized values. An optimum plant design was required to can achieve the predicted operating results, at a known level of risk, while treating the variability inherent in the ore body."

Jan 1, 2007

Flotation Circuit Optimisation - Towards More Sustainable Practice

Sep 13, 2010

By G. S. Dobby, J. A. Finch

"I. INTRODUCTIONA significant development in flotation over the past few years has been the increasing industrial use of flotation columns, primarily in Canada. The column differs dramatically from conventional mechanical flotation machines, both in design end operating philosophy, which has been a principal reason for its slow acceptance by the mineral industry. Boutin, Tremblay and Wheeler (1. 2) developed the concept in the early 1960's and since then plant and laboratory columns have been marketed commercially by Column Flotation Company of Canada Ltd. In 1980-81 at Mines Gaspe, Quebec, three columns replaced 13 conventional cleaners in a molybdenum upgrading circuit, with superior results (3). Since then many of the copper producers in British Columbia have installed columns for copper and molybdenum cleaning, including Gibraltar, Lornex, Highmont and Island Copper. There now appears to be widespread interest in flotation columns.The column is particularly attractive for applications involving multiple cleaning stages and can upgrade In a single stage compared with several stages of mechanical cells. This results in simpler, more controllable circuits. Importantly, the column itself is well suited to computer control. A significant problem, however, has been that of translating laboratory data to plant performance. The purposes of this communication are to address the problem of column scale-up and to describe some of the transport mechanisms of a flotation column, leading to a kinetics based model.A schematic of a flotation column is shown in Figure]. Industrial columns are up to 13 m high and 0.3 to 1.8 m in cross section (either square or circular). Three zones can be identified:a collection zone, with feed entering 2 to 3 m below the top of the column and descending against rising bubbles generated at a gas sparger; a washing zone, where a packed bubble bed is generated by a downward flow of wash water; and a conventional froth (2 - 5 cm thick), the sole purpose of which is particle transport to the launder. The tailings withdrawal at the bottom of the column is controlled at a rate slightly greater than the feed flowrate (called a positive bias).An important element is the washwater, added just below the froth zone. The component of the washwater that flows downward (to make up the bias) is sufficient to prevent coalescence of rising gas bubbles. The packed bubble beg so generated is very efficient at suppressing gangue entrainment to the concentrate."

Jan 1, 1985

By H. Kolcz, G. S. Dobby, R. Stratton-Crawley, S. W. Wilson

"The Matte Separation plant at Inco's Copper Cliff Smelter Complex is described. The continuing implementation of flotation column technology in the flowsheet in various applications is reviewed. Comparative studies on 0.038, 0.10, 1.1 and 1.8 m diameter columns have been carried out. It was demonstrated that consistent metallurgical performance was obtained with both pilot- and plant-scale units. Grade-recovery relationships for plant columns can be predicted with confidence from data obtained from test equipment. The work indicates further areas of the flowsheet in which columns present an attractive alternative to conventional cells. INCO’s MATTE SEPARATION PROCESSNickel concentrate from Inco’s Sudbury area mills has been processed in the Copper Cliff smelter for sixty years. Prior to that, Sudbury ores had been smelted directly. Historically, copper-nickel separation from smelter converter matte was achieved by the classical Orford process. In the mid-1940s Inco developed an improved separation scheme based on mineral processing methods, the Matte Separation Process. A generalized Copper Cliff Smelter Complex flowsheet is shown in Figure 1.Iron sulfide and gangue contained in the nickel concentrate are rejected in the smelting-converting process. The molten product, typically containing 50% Ni, 25% CU and 22% s, is cast at about 1000 ºC, into floor moulds and allowed to slowly cool for four days. During this period nickel sulfide (heazlewoodite, Ni,S,), copper sulfide (chalcocite, cu,S) and a copper-nickel metallic alloy precipitate and form a coarse grain structure that is amenable to separation by physical means. The phase chemistry of this system has been described previously by Sproule et al (1). This matte then becomes the feed to the Matte Separation Process.A simplified block flowsheet of the Matte Separation Process is shown in Figure 2. Matte ingots, typically weighing 20 tonnes each, are broken and crushed in a three stage crushing plant to approximately minus 0.01 m and conveyed to the Matte Separation building. Grinding is carried out in two parallel circuits each consisting of a rod and ball mill in series producing a flotation feed which is 65% minus 44 microns. Typical throughput of each grinding circuit is 650 tonnes/day. The metallic fraction of the feed is recovered by magnetic separation. This product, containing about 66% Ni and 15% CU, is a major component of the feed to the Copper Cliff Nickel Refinery."

Jan 1, 1990

By Frederick Laist

I. EXPERIMENTAL FLOTATION CONCENTRATION INTRODUCTION EARLY in 1914 it was decided to test, on a fairly large scale, the treatment by flotation of Anaconda slime and mill tailing. For this purpose a standard-type Minerals. Separation machine was installed at the Washoe Reduction Works during May and June, 1914. This was followed by the. installation of a full-size Callow pneumatic machine plant. Experiments were also made, on a smaller scale, with the Froment, the Towne, the Fields, and the Anaconda flotation machines. The last-named machine was developed at this plant. In addition to the tests made in the standard-type Minerals Separation machine some tests were made using a Minerals Separation machine of the sub-aeration type. During the series of experiments a large variety of oils was tested. Experiments were also conducted using both round-table feed and tailing to determine whether it would be better to displace the round tables by flotation for the treatment of the slime, or to supplement the round tables by flotation of the round-table tailing. A series of tests was also made on the treatment of the mill tailing by grinding followed by flotation to determine the relative merits of flotation and leaching for the treatment of this product. In addition, flotation tests were made on mixtures of mill tailing and slime. The round-table feed referred to above is the total slime from the mill. It contains about 35 per cent. colloidal solids and approximately 90 to 95 per cent. of the total solids will pass through 200 mesh (0.067 mm.). It assays from 2.3 to 2.6 per cent. Cu. The mill tailing referred to above is the total discard from the mill, exclusive of the slime. It is all finer than 2 mm. and about 90 to 95 per cent. will remain on 0.25 mm. It assays about 0.60 per cent. Cu. A brief summary of the experimental flotation results follows:

Jan 3, 1916

By Patrick Pelletier, Pierre-Alexandre Bossé, Julie Fournier, Gianni Bartolacci, Jayson Tessier, Ahmed Bouajila, Carl Duchesne

"This paper summarizes research into the study of the control of flotation processes based on froth images. The use of numerical image analysis techniques for the extraction of significant patterns (froth structure and colour) from industrial flotation froths is discussed.First, the froth was analysed by the use of the Multivariate Image Analysis (MIA) method to extract the spectral variation contained in a RBG image. The Partial Least Squares (PLS) was applied to develop the empirical model for the prediction of froth grade. The results of this application are illustrated using one industrial case study.Second, the froth was also analysed by Gray Level Co-occurrence Matrix (GLCM) and Wavelet Transform Analysis (WTA) to extract features related more to morphological aspects. Since there is useful information hidden in froth texture, these methods are used as texture descriptor to classify different types of froths.Third, a control strategy based on a froth structure indicator was developed and implemented on an industrial zinc flotation circuit. The feedback controller uses a reagent flow-rate in order to maintain the froth structure at its set point. Process improvements obtained with the implemented control strategy are highlighted.Finally, the feasibility to implement a hybrid control strategy consisting in a froth structure supervision controller based on the froth concentrate grade estimated by MIA and recovery inferred by image analysis is discussed.INTRODUCTIONThe development of control strategies to achieve satisfactory control performance has always been a great challenge for engineers and the need for improved process diagnosis, control and optimization has become more and more evident for the mineral processing industry in the last decades. That is why new process variables need to be measured particularly in highly multivariable processes such as flotation. This industrial process is subject to a wide variety of disturbances mainly generated by frequent and sometimes abrupt changes in physical and/or chemical ore characteristics and also, due to some irregularities in manual process operating procedures. A flotation circuit scheme is always a complex network of more than two dozens slurry streams. Information about those streams (% solid, metal content analysis and flow rates) is important for process diagnosis performance evaluation and control. Also, because of the grade decrease and increasing complexity of the new processed ores, more instrumentation outputs and more powerful and significant pr"

Jan 1, 2005