WorldWideScience

Sample records for conventional froth flotation

  1. Improving the performance of conventional and column froth flotation cells

    Energy Technology Data Exchange (ETDEWEB)

    Arnold, B.J. [CQ Inc., Homer City, PA (United States)

    1995-11-01

    Many existing mining operations hover on the brink of producing competitively priced fuel with marginally acceptable sulfur levels. To remain competitive, these operations need to improve the yield of their coal processing facilities, lower the sulfur content of their clean coal, or lower the ash content of their clean coal. Fine coal cleaning processes offer the best opportunity for coal producers to increase their yield of high quality product. Over 200 coal processing plants in the U.S. already employ some type of conventional or column flotation device to clean fines. an increase in efficiency in these existing circuits could be the margin required to make these coal producers competitive.

  2. Frothing in flotation. Volume 2: Recent advances in coal processing

    Energy Technology Data Exchange (ETDEWEB)

    Laskowski, J.S. [ed.] [Univ. of British Columbia, Vancouver, British Columbia (Canada); Woodburn, E.T. [ed.] [Univ. of Manchester Inst. of Science and Technology (United Kingdom)

    1998-11-01

    This volume summarizes the achievements on various aspects of flotation froth properties and behavior, and relationship between froth appearance and flotation performance. Flotation kinetics involves a number of mass transfer processes with some of them being critically determined by the behavior of froth. Since froth is complex, and controlled experimentation is difficult, the froth phase was, until recently, either ignored or treated entirely empirically. With wide applications of flotation columns, the behavior of the froth is now often recognized as being dominant in determining flotation performance, and the research in this area is one of the most actively pursued. Contents include: Frothers and frothing; Effect of particle and bubble size on flotation kinetics; Water content and distribution in flotation froths; Mechanisms operating in flotation froths; Characterization of flotation froth; Simultaneous determination of collection zone rate constant and froth zone recovery factor; Modelling of froth dynamics with implications for feed-back control; The interrelationship between flotation variables and froth appearance; Froth image analysis in a flotation control system; Kinetic flotation modelling using froth imaging data; and Dependence of froth behavior on galvanic interactions.

  3. Selective detachment process in column flotation froth

    Energy Technology Data Exchange (ETDEWEB)

    Honaker, R.Q.; Ozsever, A.V.; Parekh, B.K. [University of Kentucky, Lexington, KY (United States). Dept. of Mining Engineering

    2006-05-15

    The selectivity in flotation columns involving the separation of particles of varying degrees of floatability is based on differential flotation rates in the collection zone, reflux action between the froth and collection zones, and differential detachment rates in the froth zone. Using well-known theoretical models describing the separation process and experimental data, froth zone and overall flotation recovery values were quantified for particles in an anthracite coal that have a wide range of floatability potential. For highly floatable particles, froth recovery had a very minimal impact on overall recovery while the recovery of weakly floatable material was decreased substantially by reductions in froth recovery values. In addition, under carrying-capacity limiting conditions, selectivity was enhanced by the preferential detachment of the weakly floatable material. Based on this concept, highly floatable material was added directly into the froth zone when treating the anthracite coal. The enriched froth phase reduced the product ash content of the anthracite product by five absolute percentage points while maintaining a constant recovery value.

  4. Analysis of Texture of Froth Image in Coal Flotation

    Institute of Scientific and Technical Information of China (English)

    路迈西; 王凡; 刘晓文日; 刘文礼; 王勇

    2001-01-01

    Froth image features of coal flotation have been extracted and studied by neighboring grey level dependence matrix, spatial grey level dependence matrix and grey level histogram. In this paper, a basic algorithm of unsupervised learning pattern classification is presented, and coal flotation froth images are classified by means of self-organizing map (SOM). By extracting features from 51 flotation froth images with laboratory column, four types of froth images are classified. The correct rate of SOM cluster is satisfactory. And a good relationship of froth type with average ash content is also observed.

  5. Evaluation of the selective detachment process in flotation froth

    Energy Technology Data Exchange (ETDEWEB)

    Honaker, R.Q.; Ozsever, A.V. [University of Kentucky, Lexington, KY (United States). Dept. for Mining Engineering

    2003-10-01

    The improved selectivity between particles of varying degrees of hydrophobicity in flotation froths has been well documented in literature, especially in the deep froths utilized in flotation columns. The phenomenon is believed to be due to the selective detachment process whereby the least hydrophobic particles are released from the bubble surface upon bubble coalescence. To quantify the selective detachment process, column flotation experiments were performed under various operating conditions that provided varying amounts of reflux between the froth and collection zones. The flotation column incorporated the ability to provide instantaneous stoppage of the process streams and separation between the collection and froth zones after ensuring steady-state operation of the column. The samples collected from the two zones and process streams were evaluated to quantify the flotation rate distribution of the particles comprising each sample. The flotation rate was used as an indicator of the degree of hydrophobicity and thus a relative measure of the binding force between the particle and bubble in the froth zone. The flotation rate data was used as input into well known flotation models to obtain the froth zone recovery rate and the quantity of material that refluxes between the collection and froth zones.

  6. Engineering development of advanced froth flotation. Volume 2, Final report

    Energy Technology Data Exchange (ETDEWEB)

    Ferris, D.D.; Bencho, J.R.; Torak, E.R. [ICF Kaiser Engineers, Inc., Pittsburgh, PA (United States)

    1995-03-01

    This report is an account of findings related to the Engineering and Development of Advanced Froth Flotation project. The results from benchscale and proof-of-concept (POC) level testing are presented and the important results from this testing are used to refine a conceptual design and cost estimate for a 20 TPH Semi-Works Facility incorporating the final proposed technology.

  7. Effect of solids on pulp and froth properties in flotation

    Institute of Scientific and Technical Information of China (English)

    张炜

    2014-01-01

    Froth flotation is a widely used process of particle separation exploiting differences in surface properties. It is important to point out that overall flotation performance (grade and recovery) is a consequence of the quality and quantity of the solid particles collected from the pulp phase, transported into the froth phase, and surviving as bubble-particle aggregates into the overflow. This work will focus on studying these phenomena and will incorporate the effects of particle hydrophobicities in the 3-phase system. Solids are classed as either hydrophilic non-sulphide gangue (e.g. silica, talc), hydrophilic sulphide (e.g. pyrite), or hydrophobic sulphide (e.g. sphalerite). Talc is a surface-active species of gangue that has been shown to behave differently from silica (frother adsorbs on the surface of talc particles). Both are common components of ores and will be studied in detail. The focus of this work is to investigate the role of solids on pulp hydrodynamics, froth bubble coalescence intensity, water overflow rate with solids present, and in particular, the interactions between solids, frother and gas on the gas dispersion parameters. The results show that in the pulp zone there is no effect of solids on bubble size and gas holdup;in the froth zone, although hydrophilic particles solely do not effect on the water overflow rate, hydrophobic particles produce higher intensity of rates on water overflow and bubble coalescence, and many be attributed to the water reattachment.

  8. Dynamic Modeling and Real-Time Monitoring of Froth Flotation

    Directory of Open Access Journals (Sweden)

    Khushaal Popli

    2015-08-01

    Full Text Available A dynamic fundamental model was developed linking processes from the microscopic scale to the equipment scale for batch froth flotation. State estimation, fault detection, and disturbance identification were implemented using the extended Kalman filter (EKF, which reconciles real-time measurements with dynamic models. The online measurements for the EKF were obtained through image analysis of froth images that were captured and analyzed using the commercial package VisioFroth (Metsor Minerals. The extracted image features were then correlated to recovery using principal component analysis and partial least squares regression. The performance of real-time state estimation and fault detection was validated using batch flotation of pure galena at various operating conditions. The image features that were strongly representative of recovery were identified, and calibration and validation were performed against off-line measurements of recovery. The EKF successfully captured the dynamics of the process by updating the model states and parameters using the online measurements. Finally, disturbances in the air flow rate and impeller speed were introduced into the system, and the dynamic behavior of the flotation process was successfully tracked and the disturbances were identified using state estimation.

  9. Relationship between solids flux and froth features in batch flotation of sulphide ore

    Institute of Scientific and Technical Information of China (English)

    YANG Xiao-sheng; Aldrich Chris

    2005-01-01

    The froth features in the batch flotation of a sulphide ore were investigated by using the digital image parameters of the froth, the small number emphasis(Nsne), the average grey level(Dagl) and the instability number(Nins), under different conditions of impeller speeds and aeration rates. It is found that the value of Nsne is strongly dependent on the average bubble size of the froth and Dagl on the volume fraction of solid in the froth, and the froth features during the batch flotation are influenced by impeller speed and aeration rate. A kinetic model of the concentrate solid flux was developed which relates the flotation process to the image parameters, Nsne and Dagl of the froth and predictions are well consistent with the experimental data.

  10. Advanced froth flotation techniques for fine coal cleaning

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, R.H.; Luttrell, G.H. [Virginia Polytechnic Institute and State Univ., Blacksburg, VA (United States)

    1994-12-31

    Advanced column flotation cells offer many potential advantages for the treatment of fine coal. The most important of these is the ability to achieve high separation efficiencies using only a single stage of processing. Unfortunately, industrial flotation columns often suffer from poor recovery, low throughput and high maintenance requirements as compared to mechanically-agitated conventional cells. These problems can usually be attributed to poorly-designed air sparging systems. This article examines the problems of air sparging in greater detail and offers useful guidelines for designing bubble generators for industrial flotation columns. The application of these principles in the design of a successful advanced fine coal flotation circuit is also presented.

  11. The influence of solvent and demulsifier additions on nascent froth formation during flotation recovery of Bitumen from Athabasca oil sands

    Energy Technology Data Exchange (ETDEWEB)

    Stasiuk, E.N. [Chemistry Department, University of Calgary, Calgary, AB (Canada); Schramm, L.L. [Petroleum Recovery Institute, Alberta Research Council, 250 Karl Clark Road , T6N 1E4 Edmonton, AB (Canada)

    2001-10-25

    In the commercial slurry conditioning and flotation process applied to Athabasca oil sands the primary bituminous froth can contain significant amounts of emulsified water and suspended solids. Previous work [Fuel Process. Technol. 56 (1998) 243] has shown that a small chemical addition during the nascent froth process can yield froth of higher quality, without sacrificing bitumen recovery or increasing tight emulsion-forming tendency. In the present work we have investigated the addition of demulsifiers, mostly water-in-oil (W/O) emulsion breaking agents, in an attempt to encourage water droplet coalescence and separation from nascent froth. It was found that certain combinations of high HLB surfactants and solvents can be added in small amounts during the nascent froth process to cause significant reductions in froth water content without sacrificing bitumen recovery. The existence of an optimum surfactant concentration for such beneficial additives correlates with a minimum in interfacial tension and is consistent with conventional oilfield demulsifier experience. The application of our results could lead to a substantial increase in the throughput capacity of froth handling and treatment plants.

  12. Development of an on-line froth vision system for control of coal flotation

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen, K.K.; Holtham, P.N.; Brake, I.R. [University of Queensland, Brisbane, Qld. (Australia). Julius Kruttschnitt Mineral Research Centre

    1998-12-31

    Flotation is one of the important processes used to recover minus 0.5 mm coal, but the automatic control of flotation has always been difficult due to a lack of suitable process instrumentation. While cell levels can be readily measured, and feed and tailings pulps can be assayed for ash level and solids concentration using on-stream analysers, these measurements alone are not generally sufficient for effective process control. Visual inspection of froth conditions by the flotation operator can provide additional data, and experienced operators are able to make process adjustments based on examination of froth characteristics such as average bubble size and froth mobility. At present, instrumentation to evaluate the appearance of the froth is not available, and hence this aspect of flotation plant operation is still manually controlled. This paper presents the results from the development of an industrial video-based pattern recognition system for image analysis of flotation froth. The system has been applied to one of the sixteen 3 m diameter Microcel flotation columns at Peak Downs coal preparation plant in central Queensland. Results from the system to date show that it can successfully identify froth type and estimate average bubble size and froth speed. The machine vision system currently developed provides sufficient processing power to support minute by minute updates of these froth characteristics as well as a live video output to the screen. On-line predictions of percent ash and solids in the froth are well correlated with those obtained by laboratory analysis. The system is currently being linked to the Peak Downs plant PLC to allow a trial of closed loop control of flotation. 5 refs., 7 figs.

  13. Performance Recognition for Sulphur Flotation Process Based on Froth Texture Unit Distribution

    Directory of Open Access Journals (Sweden)

    Mingfang He

    2013-01-01

    Full Text Available As an important indicator of flotation performance, froth texture is believed to be related to operational condition in sulphur flotation process. A novel fault detection method based on froth texture unit distribution (TUD is proposed to recognize the fault condition of sulphur flotation in real time. The froth texture unit number is calculated based on texture spectrum, and the probability density function (PDF of froth texture unit number is defined as texture unit distribution, which can describe the actual textual feature more accurately than the grey level dependence matrix approach. As the type of the froth TUD is unknown, a nonparametric kernel estimation method based on the fixed kernel basis is proposed, which can overcome the difficulty when comparing different TUDs under various conditions is impossible using the traditional varying kernel basis. Through transforming nonparametric description into dynamic kernel weight vectors, a principle component analysis (PCA model is established to reduce the dimensionality of the vectors. Then a threshold criterion determined by the TQ statistic based on the PCA model is proposed to realize the performance recognition. The industrial application results show that the accurate performance recognition of froth flotation can be achieved by using the proposed method.

  14. A modified release analysis procedure using advanced froth flotation mechanisms. Final technical report, September 1, 1995--August 31, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Honaker, R.Q.; Mohanty, M.K. [Southern Illinois Univ., Carbondale, IL (United States)

    1997-05-01

    Recent studies indicate that the optimum separation performances achieved by multiple stage cleaning using various column flotation technologies and single stage cleaning using a Packed-Flotation Column are superior to the performance achieved by the traditional release procedure, especially in terms of pyritic sulfur rejection. This superior performance is believed to be the result of the advanced flotation mechanisms provided by column flotation technologies. Thus, the objective of this study was to develop a suitable process utilizing the advanced froth flotation mechanisms to characterize the true flotation response of a coal sample. This investigation resulted in the development of a modified coal flotation characterization procedure, termed as the Advanced Flotation Washability (AFW) technique. The apparatus used for this procedure is a batch operated Packed-Column device which provides enhanced selectivity due to a plug-flow environment and a deep froth zone. The separation performance achieved by the AFW procedure was found to be superior to those produced by the conventional tree and release procedures for three nominally -100 mesh coal samples and two micronized samples. The largest difference in separation performance was obtained on the basis of product pyritic sulfur content. A comparison conducted between the AFW and the release procedures at an 80% recovery value showed that the AFW technique provided a 19% improvement in the reduction of pyritic sulfur. For an Illinois No. 5 coal sample, this improvement corresponded to a reduction in pyritic sulfur content from 1.38% to 0.70% or a total rejection of 66%. Micronization of the sample improved the pyritic sulfur rejection to 85% while rejecting 92% of the ash-bearing material. In addition, the separation performance provided by the AFW procedure was superior to that obtained from multiple cleaning stages using a continuous Packed-Column under both kinetic and carrying-capacity limiting conditions.

  15. Performance of classic oils and lubricating oils in froth flotation of Ukraine coal

    Energy Technology Data Exchange (ETDEWEB)

    Ibrahim Sonmez; Yakup Cebeci [Cumhuriyet University, Sivas (Turkey). Metallurgical and Materials Engineering Department, Engineering Faculty

    2006-09-15

    In this study, the appropriate collector and collector amount for Ukraine coal in froth flotation was determined. For this purpose, the performance of classic oils (kerosene, diesel-oil and fuel-oil) and lubricating oils (spindle oil, bright stock and heavy neutral) was evaluated by combustible recovery, ash rejection and efficiency index. It was found that the combustible recovery and ash rejection changed, depending on the type and concentration of oil. The maximum combustible recovery was obtained by using bright stock. It was determined that bright stock, fuel-oil and kerosene were suitable for the flotation of Ukraine coal. On considering the flotation efficiency index values, the best results were obtained with bright stock and diesel-oil. Consequently, it was shown that bright stock and spindle oil could be used as alternative oils instead of classic oils for cleaning of Ukraine coal by the froth flotation. 28 refs., 4 figs., 1 tab.

  16. Separation of polyethylene terephthalate from municipal waste plastics by froth flotation for recycling industry

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Chong-Qing; Wang, Hui, E-mail: huiwang1968@163.com; Liu, You-Nian

    2015-01-15

    Highlights: • Factors of NaOH treatment were studied by orthogonal and single factor experiments. • Mechanism of alkaline treatment for facilitating flotation was manifested. • Flotation separation of PET was achieved with high purity and efficiency. • A flow sheet of purification PET from MWP was designed. - Abstract: Recycling is an effective way to manage plastic wastes and receives considerable attention. Since plastic mixtures are difficult to recycle because of their intrinsic characteristics, separation of mixed plastics is the key problem for recycling. Separation of polyethylene terephthalate (PET) from municipal waste plastics (MWP) by froth flotation combined with alkaline pretreatment was investigated for recycling industry. The effect of process variables was estimated by L{sub 9} (3{sup 4}) orthogonal array of experiments and single factor experiments. The optimum conditions of alkaline pretreatment are 10 wt% sodium hydroxide, 20 min and 70 °C. After alkaline pretreatment under optimum conditions, flotation separation PET from acrylonitrile–butadiene–styrene, polystyrene, polycarbonate or polyvinyl chloride was achieved with high purity and efficiency. The purity of PET is up to 98.46% and the recovery is above 92.47%. A flow sheet of separation PET from MWP by a combination of froth flotation and sink float separation was designed. This study facilitates industrial application of plastics flotation and provides technical insights into recycling of waste plastics.

  17. Separation of polyvinyl chloride (PVC) from automobile shredder residue (ASR) by froth flotation with ozonation

    Energy Technology Data Exchange (ETDEWEB)

    Reddy, Mallampati Srinivasa [Department of Chemical Engineering, Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8527 (Japan)]. E-mail: srireddys@hiroshima-u.ac.jp; Kurose, Keisuke [Department of Chemical Engineering, Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8527 (Japan); Okuda, Tetsuji [Environmental Research and Management Center, Hiroshima University, 1-5-3 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8513 (Japan); Nishijima, Wataru [Environmental Research and Management Center, Hiroshima University, 1-5-3 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8513 (Japan); Okada, Mitsumasa [Department of Chemical Engineering, Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima, Hiroshima 739-8527 (Japan)

    2007-08-25

    The purpose of this study is to develop froth flotation to separate polyvinyl chloride (PVC) from automobile shredder residue (ASR) plastic mixtures of variable composition. Some polymers in ASR polymer mixtures have similar density and hydrophobicity with PVC and thus selective flotation of PVC from ASR polymer mixtures cannot be achieved. The present study focused on the surface modification of PVC with ozonation, and then the modified PVC can be separated from other polymers by the following froth flotation. The results of this study indicate that the selective recovery of PVC from real ASR polyethylene tetra pethelate (PET), polymethyl methacrylate (PMMA), polybutyl methacralate (PBMA), ethyl acrylate (EA), polycarbonate (PC) and rubber mixtures can be accomplished in a three-step process involving a gravity separation, ozonation and froth flotation. The rubber was removed from other heavy ASR (PVC, PET, PMMA, PBMA, EA and PC) polymers by froth flotation without mixing. It was found that ozonation process produced the desired difference in contact angle required (from 89.5 to 73.0{sup o}) for separation of PVC from other heavy ASR polymers, whereas the contact angles of other polymers was slightly decreased. The most of the load ASR, i.e. about 72.4% is floated away and 27.6% was settled down. The highest component 96.7% of PVC was recovered in the settled fraction. As a result of this research effort, the surface modification of PVC with ozonation can be efficiently useful to separate the PVC from other similar density ASR mixed polymers.

  18. Optimization of a laboratory-scale froth flotation process using response surface methodology

    Energy Technology Data Exchange (ETDEWEB)

    V.K. Kalyani; Pallavika; T. Gouri Charan; Sanjay Chaudhuri [Central Mining Research Institute, Dhanbad (India). IT Centre

    2005-09-01

    Froth flotation is a universally accepted process for the beneficiation of coal fines. However, the process variables, collector dosage, frother dosage, and pulp density need to be optimized for each coal. In the present work, response surface methodology has been applied for optimization of yield at a desired ash level. Using this technique, interaction, contours, and three-dimensional diagrams have been developed to observe the behavior of the independent variables as well as interaction of the variables. A three-dimensional diagram has also been developed to visualize the behavior of the desirability function. In this paper, attempts have been made to evaluate the performance of the froth flotation process using response surface methodology.

  19. Taguchi optimization: Case study of gold recovery from amalgamation tailing by using froth flotation method

    Science.gov (United States)

    Sudibyo, Aji, B. B.; Sumardi, S.; Mufakir, F. R.; Junaidi, A.; Nurjaman, F.; Karna, Aziza, Aulia

    2017-01-01

    Gold amalgamation process was widely used to treat gold ore. This process produces the tailing or amalgamation solid waste, which still contains gold at 8-9 ppm. Froth flotation is one of the promising methods to beneficiate gold from this tailing. However, this process requires optimal conditions which depends on the type of raw material. In this study, Taguchi method was used to optimize the optimum conditions of the froth flotation process. The Taguchi optimization shows that the gold recovery was strongly influenced by the particle size which is the best particle size at 150 mesh followed by the Potassium amyl xanthate concentration, pH and pine oil concentration at 1133.98, 4535.92 and 68.04 gr/ton amalgamation tailing, respectively.

  20. Activation of Sphalerite by Ammoniacal Copper Solution in Froth Flotation

    Directory of Open Access Journals (Sweden)

    Xian Xie

    2016-01-01

    Full Text Available The activation of sphalerite particles by ammoniacal copper solution (ACS was investigated in this study. This microflotation study was conducted on a single sphalerite mineral with the particles size of 38 μm to 75 μm. Results showed that ACS has somewhat better activation effect than copper sulphate (a traditional activator with sodium isobutyl xanthate as the collector. Agglomeration observation, contact angle measurement, and X-ray photoelectron spectroscopy measurement results of sphalerite particles verified the superiority of this new activator. Therefore, the substitution of copper sulphate with ACS would increase the separation efficiency not only in marmatite flotation but also in sphalerite flotation.

  1. Separation of polyethylene terephthalate from municipal waste plastics by froth flotation for recycling industry.

    Science.gov (United States)

    Wang, Chong-Qing; Wang, Hui; Liu, You-Nian

    2015-01-01

    Recycling is an effective way to manage plastic wastes and receives considerable attention. Since plastic mixtures are difficult to recycle because of their intrinsic characteristics, separation of mixed plastics is the key problem for recycling. Separation of polyethylene terephthalate (PET) from municipal waste plastics (MWP) by froth flotation combined with alkaline pretreatment was investigated for recycling industry. The effect of process variables was estimated by L9 (3(4)) orthogonal array of experiments and single factor experiments. The optimum conditions of alkaline pretreatment are 10 wt% sodium hydroxide, 20 min and 70°C. After alkaline pretreatment under optimum conditions, flotation separation PET from acrylonitrile-butadiene-styrene, polystyrene, polycarbonate or polyvinyl chloride was achieved with high purity and efficiency. The purity of PET is up to 98.46% and the recovery is above 92.47%. A flow sheet of separation PET from MWP by a combination of froth flotation and sink float separation was designed. This study facilitates industrial application of plastics flotation and provides technical insights into recycling of waste plastics. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Kinetic approach to the study of froth flotation applied to a lepidolite ore

    Institute of Scientific and Technical Information of China (English)

    Nathlia Vieceli; Fernando O Duro; Carlos Guimares; Carlos A Nogueira; Manuel F C Pereira; Fernanda Margarido

    2016-01-01

    The number of published studies related to the optimization of lithium extraction from low-grade ores has increased as the demand for lithium has grown. However, no study related to the kinetics of the concentration stage of lithium-containing minerals by froth flotation has yet been reported. To establish a factorial design of batch flotation experiments, we conducted a set of kinetic tests to determine the most selective alternative collector, define a range of pulp pH values, and estimate a near-optimum flotation time. Both collectors (Aeromine 3000C and Armeen 12D) provided the required flotation selectivity, although this selectivity was lost in the case of pulp pH values outside the range between 2 and 4. Cumulative mineral recovery curves were used to adjust a classical kinetic model that was modified with a non-negative parameter representing a delay time. The computation of the near-optimum flotation time as the maximizer of a separation effi-ciency (SE) function must be performed with caution. We instead propose to define the near-optimum flotation time as the time interval re-quired to achieve 95%–99% of the maximum value of the SE function.

  3. Hybrid selective surface hydrophilization and froth flotation separation of hazardous chlorinated plastics from E-waste with novel nanoscale metallic calcium composite.

    Science.gov (United States)

    Mallampati, Srinivasa Reddy; Heo, Je Haeng; Park, Min Hee

    2016-04-05

    Treatment by a nanometallic Ca/CaO composite has been found to selectively hydrophilize the surface of polyvinyl chloride (PVC), enhancing its wettability and thereby promoting its separation from E-waste plastics by means of froth flotation. The treatment considerably decreased the water contact angle of PVC, by about 18°. The SEM images of the PVC plastic after treatment displayed significant changes in their surface morphology compared to other plastics. The SEM-EDS results reveal that a markedly decrease of [Cl] concentration simultaneously with dramatic increase of [O] on the surface of the PCV samples. XPS results further confirmed an increase of hydrophilic functional groups on the PVC surface. Froth flotation at 100rpm mixing speed was found to be optimal, separating 100% of the PVC into a settled fraction of 96.4% purity even when the plastics fed into the reactor were of nonuniform size and shape. The total recovery of PVC-free plastics in E-waste reached nearly 100% in the floated fraction, significantly improved from the 20.5wt% of light plastics that can be recovered by means of conventional wet gravity separation. The hybrid method of nanometallic Ca/CaO treatment and froth flotation is effective in the separation of hazardous chlorinated plastics from E-waste plastics. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Evaluation of biosurfactant obtained from Lactobacillus pentosus as foaming agent in froth flotation.

    Science.gov (United States)

    Vecino, X; Devesa-Rey, R; Cruz, J M; Moldes, A B

    2013-10-15

    This study analyzes the kinetics of sediment sorption on two chemical surfactants (Tween 20 and SDS) and a biotechnologically produced surfactant (obtained from Lactobacillus pentosus). Biosurfactants were produced by fermentation of hemicellulosic sugars from vineyard pruning waste supplied as a substrate to L. pentosus. Results obtained showed that almost no SDS was adsorbed onto the sediments, whereas Tween 20 and biosurfactants from L. pentosus were absorbed after a few minutes. Kinetic models revealed that adsorption of surfactant onto riverbed sediments is governed not only by an intra-particle diffusion model (evaluated by the Weber and Morris model), but also by surface reaction models (evaluated by first, second, third order equations and Elovich equation), showing the best fit when employing the Elovich model. The adsorption properties showed by biosurfactant from L. pentosus onto sediments present it as a potential foaming agent in froth flotation.

  5. Engineering development of advanced physical fine coal cleaning technologies: Froth flotation

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    A study conducted by Pittsburgh Energy Technology Center of sulfur emissions from about 1,300 United States coal-fired utility boilers indicated that half of the emissions were the result of burning coals having greater than 1.2 pounds of SO[sub 2] per million BTU. This was mainly attributed to the high pyritic sulfur content of the boiler fuel. A significant reduction in SO[sub 2] emissions could be accomplished by removing the pyrite from the coals by advanced physical fine coal cleaning. An engineering development project was prepared to build upon the basic research effort conducted under a solicitation for research into Fine Coal Surface Control. The engineering development project is intended to use general plant design knowledge and conceptualize a plant to utilize advanced froth flotation technology to process coal and produce a product having maximum practical pyritic sulfur reduction consistent with maximum practical BTU recovery.

  6. Engineering development of advanced physical fine coal cleaning technologies - froth flotation

    Energy Technology Data Exchange (ETDEWEB)

    Ferris, D.D.; Bencho, J.R. [ICF Kaiser Engineers, Inc., Pittsburgh, PA (United States)

    1995-11-01

    In 1988, ICF Kaiser Engineers was awarded DOE Contract No. DE-AC22-88PC88881 to research, develop, engineer and design a commercially acceptable advanced froth flotation coal cleaning technology. The DOE initiative is in support of the continued utilization of our most abundant energy resource. Besides the goal of commercialability, coal cleaning performance and product quality goals were established by the DOE for this and similar projects. primary among these were the goals of 85 percent energy recovery and 85 percent pyrite rejection. Three nationally important coal resources were used for this project: the Pittsburgh No. 8 coal, the Upper Freeport coal, and the Illinois No. 6 coal. Following is a summary of the key findings of this project.

  7. A modified release analysis procedure using advanced froth flotation mechanisms. Technical report, September 1--November 30, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Honaker, R.Q.; Mohanty, M.K. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Mining Engineering

    1995-12-31

    The objective of this study is to reinvestigate the release analysis procedure, which is traditionally conducted using a laboratory Denver cell, and to develop a modified process that can be used for all froth flotation technologies. Recent studies have found that the separation performance achieved by multiple stage cleaning and, in some cases, single stage cleaning using column flotation is superior to the performance achieved by the traditional release procedure. These findings are a result of the advanced flotation mechanisms provided by column flotation, which will be incorporated into a modified release analysis procedure developed in this study. A fundamental model of an open column has been developed which incorporates the effects of system hydrodynamics, froth drop-back, selective and non-selective detachment, operating parameters, feed solids content, and feed component flotation kinetics. Simulation results obtained during this reporting period indicate that the ultimate separation that can be achieved by a column flotation process can only be obtained in a single cleaning stage if the detachment mechanism in the froth phase is highly selective, which does not appear to occur in practice based on experimental results. Two to three cleaning stages were found to be required to obtain the ultimate performance if non-selective detachment or kinetic limiting conditions are assumed. this simulated finding agrees well with the experimental results obtained from the multiple stage cleaning of an Illinois No. 5 seam coal using the Packed-Column. Simulated results also indicate that the separation performance achieved by column flotation improves with increasing feed solids content after carrying-capacity limiting conditions are realized. These findings will be utilized in the next reporting period to modify the traditional release analysis procedure.

  8. Engineering development of advanced physical fine coal cleaning technologies: Froth flotation

    Energy Technology Data Exchange (ETDEWEB)

    1990-01-01

    An engineering development project was prepared to build upon the basic research effort conducted under a solicitation for research into Fine Coal Surface Control. The engineering development project is intended to use general plant design knowledge and conceptualize a plant to utilize advanced froth flotation technology to process coal and produce a product having maximum practical pyritic sulfur reduction consistent with maximum practical BTU recovery. This is being accomplished by utilization the basic research data on the surface properties of coal, mineral matter and pyrite obtained from the Coal Surface Control for Advanced Fine Coal Flotation Project, to develop this conceptual flowsheet. The conceptual flowsheet must be examined to identify critical areas that need additional design data. This data will then be developed using batch and semi-continuous bench scale testing. In addition to actual bench scale testing other unit operations from other industries processing fine material will be reviewed for potential application and incorporated into the design if appropriate. 31 figs., 22 tabs.

  9. Flotation advances

    Energy Technology Data Exchange (ETDEWEB)

    Clifford, D.

    1998-11-01

    This paper describes recent advances in flotation cell and mechanism design. OutoKumpu have designed larger cells, suitable for the flotation of smaller particles, with differing mechanisms for particles of different types. Froth handling is also closely controlled. Flotation cells from BQR are also described. Flotation columns are also increasingly being adopted, complementing the use of conventional flotation cells. Designs by Wemco, Multotec, VERTI-MIX, Jameson, Suedala, Quinn and Cytec are detailed, giving improvements in fine coal separation coarse particle separation, and other innovations. 8 figs., 2 tabs.

  10. Combining ZnO/microwave treatment for changing wettability of WEEE styrene plastics (ABS and HIPS) and their selective separation by froth flotation

    Science.gov (United States)

    Thanh Truc, Nguyen Thi; Lee, Byeong-Kyu

    2017-10-01

    This study reports a simple froth flotation method to separate plastic wastes of acrylonitrile-butadiene-styrene (ABS) and high impact polystyrene (HIPS) after initial hydrophilization by coating the plastics with ZnO and microwave treatment. ABS and HIPS are typical styrene-based WEEE plastics having similar density and hydrophobicity, which hinders their separation for recycling. After coating with ZnO, 2-min microwave treatment rearranged the ABS surface and thus changed its molecular mobility and increased its hydrophilicity. The combined ZnO coating/microwave treatment facilitated the selective separation of ABS and HIPS with 100% and 95.2% recovery and 95.4% and 100% purity in froth flotation, respectively. The combination of ZnO coating-microwave treatment and froth flotation can be utilized as a selective ABS/HIPS separation technique for improved recycling of WEEE plastics.

  11. A modified release analysis procedure using advanced froth flotation mechanisms: Technical report, March 1, 1996-May 31, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Honaker, R.Q., Mohanty, M.K. [Southern Illinois Univ., Department of Mining Engineering, Carbondale, IL (United States)

    1997-04-01

    Recent studies indicate that the optimum separation performances achieved by multiple stage cleaning using various column flotation technologies and single stage cleaning using a Packed-Flotation Column are superior to the performance achieved by the traditional release procedure, especially in terms of pyritic sulfur rejection. This superior performance is believed to be the result of the advanced flotation mechanisms provided by column flotation technologies. Thus, the objective of this study is to develop a suitable process utilizing the advanced froth flotation mechanisms to characterize the true flotation response of a coal sample. Work in this reporting period concentrated on developing a modified coal flotation characterization procedure, termed as Advanced Flotation Washability (AFW) technique. The new apparatus used for this procedure is essentially a batch operated packed-column device equipped with a controlled wash water system. Several experiments were conducted using the AFW technique on a relatively high sulfur, -100 mesh Illinois No. 5 run-of-mine coal sample collected from a local coal preparation plant. Similar coal characterization experiments were also conducted using the traditional release and tree analysis procedures. The best performance curve generated using the AFW technique was found to be superior to the optimum curve produced by the traditional procedures. For example, at a combustible recovery of 80%, a 19% improvement in the reduction of the pyritic sulfur content was achieved by the AFW method while the ash reduction was also enhanced by 4%. Several tests are on-going to solidify the AFW procedure and verify the above finding by conducting Anova analyses to evaluate the repeatability of the AFW method and the statistical significance of the difference in the performance achieved from the traditional and modified coal characterization procedures.

  12. Development of hydrophobicity and selective separation of hazardous chlorinated plastics by mild heat treatment after PAC coating and froth flotation.

    Science.gov (United States)

    Thanh Truc, Nguyen Thi; Lee, Chi-Hyeon; Lee, Byeong-Kyu; Mallampati, Srinivasa Reddy

    2017-01-05

    Polyvinyl chloride (PVC) containing chlorine can release highly toxic materials and persistent organic pollutants if improperly disposed of. The combined technique of powder activated carbon (PAC) coating and mild heat treatment has been found to selectively change the surface hydrophobicity of PVC, enhancing its wettability and thereby promoting its separation from heavy plastic mixtures included polycarbonate (PC), polymethyl methacrylate (PMMA), polystyrene (PS) and acrylonitrile butadiene styrene (ABS) by means of froth flotation. The combined treatments helped to rearrange the surface components and make PVC more hydrophobic, while the remaining plastics became more hydrophilic. After the treatments at 150°C for 80s the contact angle of the PVC was greatly increased from 90.5 to 97.9°. The SEM and AFM reveal that the surface morphology and roughness changes on the PVC surface. XPS and FT-IR results further confirmed an increase of hydrophobic functional groups on the PVC surface. At the optimized froth flotation and subsequent mixing at 150rpm, 100% of PVC was recovered from the remaining plastic mixture with 93.8% purity. The combined technique can provide a simple and effective method for the selective separation of PVC from heavy plastics mixtures to facilitate easy industrial recycling.

  13. Separation of polycarbonate and acrylonitrile-butadiene-styrene waste plastics by froth flotation combined with ammonia pretreatment.

    Science.gov (United States)

    Wang, Chong-Qing; Wang, Hui; Liu, Qun; Fu, Jian-Gang; Liu, You-Nian

    2014-12-01

    The objective of this research is flotation separation of polycarbonate (PC) and acrylonitrile-butadiene-styrene (ABS) waste plastics combined with ammonia pretreatment. The PC and ABS plastics show similar hydrophobicity, and ammonia treatment changes selectively floatability of PC plastic while ABS is insensitive to ammonia treatment. The contact angle measurement indicates the dropping of flotation recovery of PC is ascribed to a decline of contact angle. X-ray photoelectron spectroscopy demonstrates reactions occur on PC surface, which makes PC surface more hydrophilic. Separation of PC and ABS waste plastics was conducted based on the flotation behavior of single plastic. At different temperatures, PC and ABS mixtures were separated efficiently through froth flotation with ammonia pretreatment for different time (13 min at 23 °C, 18 min at 18 °C and 30 min at 23 °C). For both PC and ABS, the purity and recovery is more than 95.31% and 95.35%, respectively; the purity of PC and ABS is up to 99.72% and 99.23%, respectively. PC and ABS mixtures with different particle sizes were separated effectively, implying that ammonia treatment possesses superior applicability. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Kinetic comparison of biological and conventional flotation of coal

    Energy Technology Data Exchange (ETDEWEB)

    Amini, E.; Oliazadeh, M.; Kolahdoozan, M. [University of Queensland, Brisbane, Qld. (Australia)

    2009-03-15

    Froth flotation is commonly used in coal processing to selectively recover the organic material (coal) from inorganic waste material. Tabas coal, located in east Iran, contains fine disseminated pyrite which is floated with coal during flotation, and hence decreasing the quality of the final concentrate. Reagents, such as sodium cyanide, are typically added to depress pyrite. Due to the toxicity of cyanide, alternative strategies for depressing pyrite flotation are being investigated. In this paper the metallurgical performance of Tabas coal treated with sodium cyanide is compared to that of Tabas coal which has undergone bacterial treatment using Acidithiobacillus ferrooxidans. Results indicate that bacterial treatment decreases the flotation rate of pyrite and improves the selectivity between coal and gangue. The possibility of using bacteria in place of toxic chemicals such as cyanide has significant environmental benefit.

  15. Features Extraction of Flotation Froth Images and BP Neural Network Soft-Sensor Model of Concentrate Grade Optimized by Shuffled Cuckoo Searching Algorithm

    Directory of Open Access Journals (Sweden)

    Jie-sheng Wang

    2014-01-01

    Full Text Available For meeting the forecasting target of key technology indicators in the flotation process, a BP neural network soft-sensor model based on features extraction of flotation froth images and optimized by shuffled cuckoo search algorithm is proposed. Based on the digital image processing technique, the color features in HSI color space, the visual features based on the gray level cooccurrence matrix, and the shape characteristics based on the geometric theory of flotation froth images are extracted, respectively, as the input variables of the proposed soft-sensor model. Then the isometric mapping method is used to reduce the input dimension, the network size, and learning time of BP neural network. Finally, a shuffled cuckoo search algorithm is adopted to optimize the BP neural network soft-sensor model. Simulation results show that the model has better generalization results and prediction accuracy.

  16. Features extraction of flotation froth images and BP neural network soft-sensor model of concentrate grade optimized by shuffled cuckoo searching algorithm.

    Science.gov (United States)

    Wang, Jie-sheng; Han, Shuang; Shen, Na-na; Li, Shu-xia

    2014-01-01

    For meeting the forecasting target of key technology indicators in the flotation process, a BP neural network soft-sensor model based on features extraction of flotation froth images and optimized by shuffled cuckoo search algorithm is proposed. Based on the digital image processing technique, the color features in HSI color space, the visual features based on the gray level cooccurrence matrix, and the shape characteristics based on the geometric theory of flotation froth images are extracted, respectively, as the input variables of the proposed soft-sensor model. Then the isometric mapping method is used to reduce the input dimension, the network size, and learning time of BP neural network. Finally, a shuffled cuckoo search algorithm is adopted to optimize the BP neural network soft-sensor model. Simulation results show that the model has better generalization results and prediction accuracy.

  17. Removal of methylene blue from its aqueous solution by froth flotation: hydrophobic silica nanoparticle as a collector

    Science.gov (United States)

    Hu, Nan; Liu, Wei; Ding, Linlin; Wu, Zhaoliang; Yin, Hao; Huang, Di; Li, Hongzhen; Jin, Lixue; Zheng, Huijie

    2017-02-01

    Dye pollution has been a severe problem faced by worldwide environmentalists. The use of nanoparticles as adsorbents has attracted widespread interests for effectively removing dyes, while the separation of them from an aqueous solution is a difficult and important subject. For achieving the simultaneous removal of methylene blue (MB) and nanoadsorbents, this work utilized a commercial hydrophobic silica nanoparticle (SNP) (200.0 ± 10.0 nm in average particle size) as a collector and then developed a novel froth flotation technology without using any surfactants. Under the suitable conditions of anhydrous ethanol dosage of 8 mL, pH of 9.0, SNP concentration of 600 mg/L, and flotation column height of 600 mm, the removal efficiencies of MB and SNPs and the volume ratio reached 91.1 ± 4.6%, 93.9 ± 4.7%, and 10.5 ± 0.5, respectively. Subsequently, the recovered MB-adsorbed SNPs in the foamate were separated by free setting due to their high concentration and massive agglomeration. After free setting, MB could be effectively separated from the recovered MB-adsorbed SNPs by using ethanol at pH 2.0 and repeating five cycles of washing-centrifugation. Additionally, the regenerated SNPs could be reused for removing MB up to five times. Overall, this work had a significant meaning for the treatment of dye-contaminated wastewaters.

  18. Extraction of a Low Grade Zinc Ore using Gravity and Froth Flotation ...

    African Journals Online (AJOL)

    ADOWIE PERE

    used to leach base metals from sulphide concentrated with metal ... (1993). The flotation agents are known as collectors, ... lime, oleic acid, propanol, turpentine etc.) of an ore ... using Camry 25k5055 digital weighing balance. Grain Size ...

  19. Coagulation of fines in fluorite froth flotation; Coagulacion de finos en la flotacion de la fluorita

    Energy Technology Data Exchange (ETDEWEB)

    Sarquis, P. E.; Gonzalez, M.; Moyano, A.; Bazan, V.

    2011-07-01

    Fluorite, a valuable mineral in the metallurgical industry, can be found together with silicates, carbonates and oxides in ore deposits. Commercial concentrates with more than 95 % of CaF{sub 2} are obtained processing the mineral in flotation plants and using oleic acid as fluorite collector. Depressor reagents such as sodium silicate, tannin and sodium carbonate are commonly employed to allow the oleic acid selective performance. These reagents cause a dispersant effect separating the solid-liquid solution on tailing plants. Fine particles in the recovered water enter the circuit and affect the flotation efficiency. The effect of coagulant ions was studied as a method to clarify the returned water. The problem of the presence of these ions is related to its reactions with the collector by the formation of compounds and possibly on the selectivity. Variable quantities of Al{sup 3}+, Fe{sup 3}+ and Ca{sup 2}+ ions were added to the flotation to evaluate its effect on the fluorite recovery, in the selectivity and in solids content in recirculation water. Results show that some ions fail to improve water quality and are detrimental to flotation. On the contrary, some ions contribute to reduce fine content in suspension. Therefore, although there is a recovery reduction, such effect can be counteracted increasing the collector consumption a little. (Author) 21 refs.

  20. EFFECTS OF RE-ROUTING OF CONCENTRATE STREAMS IN THE INDUSTRIAL SCALE FROTH FLOTATION OF LOWER GROUP 6 PGM ORE

    Directory of Open Access Journals (Sweden)

    EMMANUEL M. SHAI

    2016-12-01

    Full Text Available The Lower Group 6 (LG6 platinum group of metals (PGM ore was subjected to batch and continuous industrial froth flotation with and without concentrate streams re-routing. The batch test indicated that the ore has a recovery of about 69%.However, the average PGM recovery before and after rougher stage rerouting during plant scale tests were 41.5 and 64.5%, respectively. The rerouting of roughers 4 to 6 streams thus successfully improved recovery by 23%.Similar results were also obtained for both PGM and PGM 4E recoveries in both cleaner and re-cleaner stages re-routing. The results obtained thus strongly suggest that the circuit PGM recovery was optimized by the re-routing. It was however further observed that the PGM grade decreased significantly while the chromium content of oxide origin increased in the concentrates after re-routing. The optimum grade and recovery combination for each metal value will thus have to be determined by the plant based on the Net Smelter Return (NSR analyses that incorporate both grade and recovery results.

  1. Investigation of thermal treatment on selective separation of post consumer plastics prior to froth flotation.

    Science.gov (United States)

    Guney, Ali; Poyraz, M Ibrahim; Kangal, Olgac; Burat, Firat

    2013-09-01

    Plastics have become the widely used materials because of their advantages, such as cheapness, endurance, lightness, and hygiene. However, they cause waste and soil pollution and they do not easily decompose. Many promising technologies are being investigated for separating mixed thermoplastics, but they are still uneconomical and unreliable. Depending on their surface characteristics, these plastics can be separated from each other by flotation method which is useful mineral processing technique with its low cost and simplicity. The main objective of this study is to investigate the flotation characteristics of PET and PVC and determine the effect of plasticizer reagents on efficient plastic separation. For that purpose, various parameters such as pH, plasticizer concentration, plasticizer type, conditioning temperature and thermal conditioning were investigated. As a result, PET particles were floated with 95.1% purity and 65.3% efficiency while PVC particles were obtained with 98.1% purity and 65.3% efficiency.

  2. Investigation of thermal treatment on selective separation of post consumer plastics prior to froth flotation

    Energy Technology Data Exchange (ETDEWEB)

    Guney, Ali; Poyraz, M. Ibrahim; Kangal, Olgac, E-mail: kangal@itu.edu.tr; Burat, Firat

    2013-09-15

    Highlights: • Both PET and PVC have nearly the same densities. • The best pH value will be 4 for optimizing pH values. • Malic acid gave the best results for selective separation of PET and PVC. - Abstract: Plastics have become the widely used materials because of their advantages, such as cheapness, endurance, lightness, and hygiene. However, they cause waste and soil pollution and they do not easily decompose. Many promising technologies are being investigated for separating mixed thermoplastics, but they are still uneconomical and unreliable. Depending on their surface characteristics, these plastics can be separated from each other by flotation method which is useful mineral processing technique with its low cost and simplicity. The main objective of this study is to investigate the flotation characteristics of PET and PVC and determine the effect of plasticizer reagents on efficient plastic separation. For that purpose, various parameters such as pH, plasticizer concentration, plasticizer type, conditioning temperature and thermal conditioning were investigated. As a result, PET particles were floated with 95.1% purity and 65.3% efficiency while PVC particles were obtained with 98.1% purity and 65.3% efficiency.

  3. ON THE USE OF FROTH FLOTATION IN THE RECOVERY OF Bacillus sphaericus SPORES

    Directory of Open Access Journals (Sweden)

    E.M. RIOS

    1997-06-01

    Full Text Available Abstract - The recovery of Bacillus sphaericus strain 2362 spores from fermented medium by batch flotation was tested under different conditions. Flotation kinetic studies were performed at 800 rpm and 3 l air/min. The pH values were adjusted at the following set of values: 5.0, 7.0 and 9.0. The results showed that the spore removal rate is influenced by the pH value. At pH equal to 5.0 we observe an adverse effect on the spore concentrate obtention. In this situation the maximum value of the concentration factor was 1.4 when the recuperation percentage was 99%. At pH equal to 7.0 the concentration factor reached the highest value, 7.0, but the recuperation percentage stayed around 96%. Field experiments with the floated material demonstrated that its larvicide activity was sufficient to keep a Culex quinquefasciatus larvae population under control at in a breeding site, during 3 months with 2 applications

  4. Engineering development of advanced physical fine coal cleaning technologies: Froth flotation. Quarterly technical progress report No. 16, July 1, 1992--September 30, 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-31

    A study conducted by Pittsburgh Energy Technology Center of sulfur emissions from about 1,300 United States coal-fired utility boilers indicated that half of the emissions were the result of burning coals having greater than 1.2 pounds of SO{sub 2} per million BTU. This was mainly attributed to the high pyritic sulfur content of the boiler fuel. A significant reduction in SO{sub 2} emissions could be accomplished by removing the pyrite from the coals by advanced physical fine coal cleaning. An engineering development project was prepared to build upon the basic research effort conducted under a solicitation for research into Fine Coal Surface Control. The engineering development project is intended to use general plant design knowledge and conceptualize a plant to utilize advanced froth flotation technology to process coal and produce a product having maximum practical pyritic sulfur reduction consistent with maximum practical BTU recovery.

  5. Separation of unburned carbon from coal fly ash through froth flotation; Sekitanbai no shisshiki datsutanso gijutsu kaihatsu shiken

    Energy Technology Data Exchange (ETDEWEB)

    Miwa, T. [Center for Coal Utilization, Japan, Tokyo (Japan); Murakami, T. [The Coal Mining Research Center, Japan, Tokyo (Japan)

    1996-09-01

    Coal ash tends to become containing more unburned carbon and porous substances depending on conditions of combustion, whose adverse effects to products due to water adsorbability, absorbability and color tones create obstacles in its utilization. Therefore, research and development works have been progressed on wet type carbon removing technology which is characterized in that coal is pulverized to preferable degrees and subjected to flotation. This paper reports the results obtained during fiscal 1995. The results may be summarized as follows: as a result of the comparison test on a column flotation machine and an FW type flotation machine of machine stirring type, the former machine showed better flotation efficiency; several methods were investigated on crushing as a treatment prior to flotation, whereas a mixer with greater circumferential speed and a homo mixer showed the highest efficiency; strength of the impact to the flotation efficiency was found to decrease in the order of pulp concentration > pretreatment time > collector addition ratio; and as a result of the evaluation on refined ash as a cement admixture and carbons as fuel, possibilities were found in them for practical application. 16 figs., 2 tabs.

  6. Estimated water requirements for the conventional flotation of copper ores

    Science.gov (United States)

    Bleiwas, Donald I.

    2012-01-01

    This report provides a perspective on the amount of water used by a conventional copper flotation plant. Water is required for many activities at a mine-mill site, including ore production and beneficiation, dust and fire suppression, drinking and sanitation, and minesite reclamation. The water required to operate a flotation plant may outweigh all of the other uses of water at a mine site, [however,] and the need to maintain a water balance is critical for the plant to operate efficiently. Process water may be irretrievably lost or not immediately available for reuse in the beneficiation plant because it has been used in the production of backfill slurry from tailings to provide underground mine support; because it has been entrapped in the tailings stored in the TSF, evaporated from the TSF, or leaked from pipes and (or) the TSF; and because it has been retained as moisture in the concentrate. Water retained in the interstices of the tailings and the evaporation of water from the surface of the TSF are the two most significant contributors to water loss at a conventional flotation circuit facility.

  7. Column flotation in coal: does it make `cents?`

    Energy Technology Data Exchange (ETDEWEB)

    Laurila, M.J.

    1997-01-01

    Column flotation technology was introduced into the coal industry in 1986. The column can produce higher grade concentrates than conventional cells. This has created a niche market for columns in recovering ultrafine (-100 mesh) coal from waste streams. However, column flotation is much more expensive than froth flotation and columns can only process a maximum of 20 tons per hour per unit and consume more reagents than conventional cells. Researchers at Michigan Technological University have found that baffles along the axis of a column vastly improved performance. Today only two companies in the US participate in the column flotation market, ICF Kaiser and Deister.

  8. The Latest Developments in Froth Flotation Separation Method%泡沫浮选分离法的最新发展动态

    Institute of Scientific and Technical Information of China (English)

    韩春雨; 李雅静; 展何伟

    2014-01-01

    泡沫分离是根据吸附的原理,向含表面活性物质的液体中鼓泡,使液体内的表面活性物质聚集在气液界面上,在液体主体上方形成泡沫层,将泡沫层和液相主体分开,就可以达到浓缩表面活性物质和净化液相主体的目的。泡沫分离是以气泡作分离介质来浓集表面活性物质的一种新型分离技术。本文注重介绍了泡沫浮选分离法的发展历史及其发展状况,另外也论述了其最新的发展动态,以及其优缺点。%Foam separation was based on the principle of adsorption , the bubble in the liquid containing the surface active substance, made the surface active substance inside the liquid gathered at the gas-liquid interface, forming foam layer above the liquid body , separate foam layer and the liquid body , which can achieve enrichment surface active material and the purpose of purifying liquid body.Foam separation was bubbles as separation medium concentration surface active material to a new kind of separation technology.The development history of froth flotation separation and its development were focused on, its latest developments, as well as their advantages and disadvantages were also discussed.

  9. 数据驱动的锑粗选泡沫图像特征优化设定%Data-driven optimal setting for froth image features of stibium rougher flotation

    Institute of Scientific and Technical Information of China (English)

    吴佳; 谢永芳; 阳春华; 桂卫华

    2016-01-01

    针对锑浮选过程中精、尾矿品位难以在线检测,浮选性能不稳定的问题,提出一种数据驱动的泡沫图像特征优化设定方法。该方法根据入矿品位类型对泡沫图像特征进行优化设定,并针对不同入矿品位类型的样本分布特点,先尝试采用案例推理的方法从历史数据中寻找浮选性能优良的泡沫状态。若经验知识不足,则采用基于多中心模糊C均值聚类与概率支持向量回归的区间II型模糊系统建模方法建立精、尾矿品位指标模型,并在此基础上利用智能优化方法寻优泡沫图像特征值。某锑浮选工业实验结果表明了所提出方法的有效性。%Due to the difficulties of measuring concentrate and tailing grade online and unstability of the flotation performance, a data-driven optimal setting for froth image features is proposed. The froth image features are optimal set according to the type of feed ore grade. Considering the distribution nature of samples of each feed grade type, it is tried to use case-based reasoning method for obtaining the froth status with optimal flotation performance from history data. When lack of enough experiential knowledge, the interval type II fuzzy system modeling method based on the multi-centers fuzzy C-means clustering and probabilistic support vector regress method is adopted to build the concentrate and tailing grade model. Then intelligent optimization algorithm is applied to search the optimal values for the froth image features. The application to the stibium flotation process shows the effectiveness of the proposed method.

  10. Assessment of the flotability of chalcopyrite, molybdenite and pyrite using biosolids and their main components as collectors for greening the froth flotation of copper sulphide ores.

    OpenAIRE

    Sobarzo, Francisco; Herrera Urbina, Ronaldo; Higueras Higueras, Pablo Leon; Sáez Navarrete, César; Godoy Faúndez, Alex; Reyes Bozo, Lorenzo; Vásquez Bestagno, Jorge

    2014-01-01

    Biosolids and representative compounds of their main components ? humic acids, sugars, and proteins ? have been tested as possible environment-friendly collectors and frothers for the flotation of copper sulphide ores. The floatability of chalcopyrite and molybdenite ? both valuable sulphide minerals present in these ores ? as well as non-valuable pyrite was assessed through Hallimond tube flotation tests. Humic acids exhibit similar collector ability for chalcopyrite and molybdenite as that ...

  11. Heterogeneous nano-Fe/Ca/CaO catalytic ozonation for selective surface hydrophilization of plastics containing brominated and chlorinated flame retardants (B/CFRs): separation from automobile shredder residue by froth flotation.

    Science.gov (United States)

    Mallampati, Srinivasa Reddy; Lee, Byoung Ho; Mitoma, Yoshiharu; Simion, Cristian

    2016-12-09

    One method of weakening the inherently hydrophobic surface of plastics relevant to flotation separation is heterogeneous nano-Fe/Ca/CaO catalytic ozonation. Nano-Fe/Ca/CaO-catalyzed ozonation for 15 min efficiently decreases the surface hydrophobicity of brominated and chlorinated flame retardant (B/CFR)-containing plastics (such as acrylonitrile-butadienestyrene (ABS), high-impact polystyrene (HIPS), and polyvinyl chloride (PVC)) in automobile shredder residue (ASR) to such an extent that their flotation ability is entirely depressed. Such a hydrophilization treatment also stimulates the ABS, HIPS, and PVC surface roughness, wetting of the surface, and the thermodynamic equilibrium conditions at the surface and ultimately changes surface polarity. SEM-EDS, AFM, and XPS analyses of the PVC and ABS surfaces demonstrated a marked decrease in [Cl/Br] and a significant increase in the number of hydrophilic groups, such as C-O, C=O, and (C=O)-O. Under froth flotation conditions at 50 rpm, about 99.5 % of ABS and 99.5 % of HIPS in ASR samples settled out, resulting in a purity of 98 and 98.5 % for ABS and HIPS in ASR samples, respectively. Furthermore, at 150 rpm, we also obtained 100 % PVC separation in the settled fraction, with 98 % purity in ASR. Total recovery of non-B/CFR-containing plastics reached nearly 100 % in the floating fraction. The amount of nano-Fe/Ca/CaO reagent employed during ozonation is very small, and additional removal of surface contaminants from the recycled ASR plastic surfaces by ozonation makes the developed process simpler, greener, and more effective.

  12. Study on Non-Collision Mineralizing Mechanism of Froth Cyclone

    Institute of Scientific and Technical Information of China (English)

    董平; 许占贤; 周晓玲

    2002-01-01

    On the basis of the mineralizing mechanism of froth cyclone, this paper expounds that the froth cyclone flotation process is accomplished in a limited centrifugal field. The main feature of air bubble mineralizing in the froth cyclone is a synthetic mineralizing process, of which the non-collision mineralization of minute air bubble separated out dominates, supplemented with the collision mineralization. Moreover, this paper points out that the hydrophobic separated out and centrifugal force strengthen the selectivity of fine coal particle, accelerate the flotation speed and improve the slime recovery.

  13. Predictive control of slurry pH based on froth characteristics for antimony flotation process%基于图像特征的锑浮选矿浆pH值预测控制

    Institute of Scientific and Technical Information of China (English)

    王晓丽; 曾子骄; 黄蕾; 谢永芳; 阳春华

    2016-01-01

    A suitable pH value of the slurry is the key for efficient froth flotation. In the industrial process, it is difficult to measure the pH value online, which causes the control delay. To solve this problem, pH-associated sensitive image features of the froth are obtained, and a soft sensor model-multi-model least squares support vector machine(LSSVM) based on affinity propagation clustering(AP) is introduced. Then, a predictive control strategy based on online support vector regression(OSVR) and differential evolution(DE) optimization for the pH is proposed. The prediction model is built offline and corrected online, and a DE optimization method is used to solve the predictive control problem to find the optimal decision variables, so as to achieve the real-time control of the slurry pH value. The industrial test results in antimony flotation show that the proposed control strategy can stabilize the pH value, and reduce the chemical consumption.%适宜的矿浆pH值是泡沫浮选高效生产的关键。针对浮选矿浆pH值无法在线检测和控制滞后的问题,提取pH关联泡沫表面敏感特征,建立基于仿射传播聚类的多模型最小二乘支持向量机软测量模型,提出一种基于差分进化的在线支持向量回归pH值预测控制方法,离线建立和在线校正pH值预测模型,采用基于差分进化优化方法求解预测控制决策变量,从而实现pH值实时控制。金锑浮选工业数据表明,所提出的控制策略稳定了矿浆pH值,减少了药剂消耗。

  14. Performance recognition using texture credit distributed SVM for froth flotation process%基于泡沫纹理信度分配SVM的矿物浮选工况识别

    Institute of Scientific and Technical Information of China (English)

    阳春华; 任会峰; 桂卫华; 鄢锋; 唐朝晖

    2011-01-01

    A performance recognition method for mineral froth flotation process is presented, where multiple imbalance exists in texture directions, feature credit and sample distribution. Firstly, second order statistics such as angular second moment, entropy, moment of inertia, moment of deficit and relevance are extracted based on four-direction fused spatial gray co-occurrence matrix to avoid the adverse effects of directions. Then information entropy is introduced to evaluate the feature credit of the texture features via the information gains. Furthermore, the imbalance of sample distribution is eliminated with between-class weighted strategy, and a performance recognition model is established using one-versus-one weighted support vector machine (OVO-WSVM). Industrial on-site experiment verifies that the proposed method can decrease the misclassification rate of small samples and increase overall recognition rate.%针对矿物浮选过程中泡沫纹理各向异性、纹理特征信度差异以及类间样本数分布不均等问题,提出一种浮选工况的自动识别方法.首先基于多角度融合的空间灰度共生矩阵计算角二阶矩、熵、惯性矩、逆差矩和相关性等二阶统计量描述泡沫纹理特征,然后引入信息熵的概念,以二阶统计量的信息增益分配各种纹理特征对分类器的信度,再通过类间样本数加权策略消除样本分布的不平衡性,最后实现了一对一加权支持向量机的浮选工况识别.工业现场泡沫图像测试结果表明,该方法能够有效降低小样本的错分率,提高整体识别率.

  15. The Flotational Mechanism of Etobicoke Creek's Self-Purification

    CERN Document Server

    Fisenko, A I

    2000-01-01

    A flotational mechanism of Etobicoke Creek's self-purification has been investigated. It is shown that the froth contains a high concentration of polluting agents. Chemical analyses of the top layer of surface water in comparison to both before and after froth collector in the course of a year are provided. As a result, the concentrations of pollutants by utilizing the model froth collector are decreased.

  16. Characterization of multiphase fluid flow during air-sparged hydrocyclone flotation by x-ray CT. Final report, 14 August 1990--13 August 1994

    Energy Technology Data Exchange (ETDEWEB)

    Miller, J.D.

    1994-10-18

    Air sparged hydrocyclone (ASH) flotation is a new particle separation technology that has been developed at the University of Utah. This technology combines froth flotation principles with the flow characteristics of a hydrocyclone such that the ASH system can perform flotation separations in less than a second. This feature provides the ASH with a high specific capacity, 100 to 600 times greater than the specific capacity of conventional flotation machines. In an effort to develop a more detailed understanding of ASH flotation, multiphase flow characteristics of the air sparged hydrocyclone were studied and the relationship of these characteristics with flotation performance was investigated. This investigation was divided into four phases. In the first phase, the time-averaged multiphase flow characteristics of the ASH during its steady state operation were studied using x-ray computed tomography (x-ray CT). In this regard, a model system, mono-sized quartz flotation with dodecyl amine as collector, using a 2 in. diameter ASH unit (ASH-2C), was selected for study. Various flow regimes, namely, the air core, the froth phase, and the swirl layer, were identified and their spatial extent established for different experimental conditions by x-ray CT analysis. In the second phase, a detailed parametric study of flotation response of the ASH for the same system was carried out in order to establish the effect of various operating variables on flotation response. The findings of this phase of investigation were then correlated with the multiphase flow characteristics as revealed by x-ray CT in the first phase. Thus, the impact of various operating variables on the flow regimes, and hence, on flotation response was established.

  17. Flotation separation of waste plastics for recycling-A review.

    Science.gov (United States)

    Wang, Chong-qing; Wang, Hui; Fu, Jian-gang; Liu, You-nian

    2015-07-01

    The sharp increase of plastic wastes results in great social and environmental pressures, and recycling, as an effective way currently available to reduce the negative impacts of plastic wastes, represents one of the most dynamic areas in the plastics industry today. Froth flotation is a promising method to solve the key problem of recycling process, namely separation of plastic mixtures. This review surveys recent literature on plastics flotation, focusing on specific features compared to ores flotation, strategies, methods and principles, flotation equipments, and current challenges. In terms of separation methods, plastics flotation is divided into gamma flotation, adsorption of reagents, surface modification and physical regulation.

  18. Column flotation testing at Suncor Energy Inc.

    Energy Technology Data Exchange (ETDEWEB)

    Cleyle, P.; Lee, L. [Suncor Energy Inc. Oil Sands, Fort McMurray, AB (Canada)

    2006-07-01

    The operations at Suncor's primary extraction plant were reviewed with reference to the column flotation process and the history of column flotation testing at Suncor. Tertiary bitumen recovery processes were also reviewed. In March and August 2005, an in-plant pilot scale column flotation test was conducted at Suncor's Millennium Primary Extraction plant near Fort McMurray, Alberta. The purpose was to evaluate the feasibility of using column flotation for tertiary bitumen recovery from cyclone overflow. The test was performed in a 4 ft diameter by 25 ft high column to determine the effects of column feed flow rate, froth wash water supply, and froth depth. The feed ranged from 0.14 to 3.79 wt per cent bitumen. Feed flow rate ranged from 59 to 237 USGPM. The test results indicated that wash water reduced froth mineral content. Increasing the wash water did not make any difference in mineral rejection. Although bitumen upgrading improved when the test column was operated at a deeper froth depth, the mineral content was not reduced. Both mechanical cell and flotation column tailings samples were collected in the flotation column tests. The average tailings composition for the last cell in the tertiary mechanical bank was 0.22 per cent bitumen, 12.10 per cent mineral, and 87.66 per cent water. At an average test column feed rate of 158 USGPM, the average tailings composition was 0.23 per cent bitumen, 12.13 per cent mineral, and 87.62 per cent water. It was concluded that flotation columns are capable of producing a tailings product similar to that of the tertiary mechanical bank. Therefore, it is feasible to use flotation columns as an alternative to mechanical cells. In fact, since there are no rotating parts requiring off-line maintenance work, flotation columns may be a better alternative from a maintenance and operations perspective. tabs., figs.

  19. Coal desulfurization by bacterial treatment and column flotation. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Kawatra, S.K. [Michigan Technological Univ., Houghton, MI (United States)

    1994-06-01

    A review of the literature showed that bacterial leaching, using the microorganism Thiobacillus ferrooxidans, was a very effective technique for removing pyrite from coal, as it could dissolve even the finest pyrite particles without the need for expensive reagents or extreme processing conditions. Unfortunately, bacterial leaching is also rather slow, and so the initial goal of this research was to decrease the leaching time as much as possible. However, this still left the bacteria needing approximately a week to remove half of the pyritic sulfur, and so a faster technique was sought. Since it had been reported in the literature that T. ferrooxidans could be used to depress the flotation of pyrite during froth flotation of coal, this was investigated further. By studying the recovery mechanisms of coal-pyrite in froth flotation, it was found that pyrite was being recovered by entrainment and by locking to coal particles, not by true flotation of hydrophobic pyrite. Therefore, no pyrite depressant could be of any significant benefit for keeping pyrite out of the coal froth product, and it was much more important to prevent entrainment from occurring. Countercurrent flotation columns were invented to essentially eliminate entrainment effects, by washing the froth and reducing mixing of the froth and tailings products. Existing flotation columns tend to be quite simple, and in order to give reasonable product quality they must be very tall (typically 30--45 feet). As a result, they have difficulty in handling the high froth volumes which occur in coal flotation, and are awkward to install in existing plants. The bulk of this project therefore concentrated on developing an improved coal flotation column, and testing it under actual plant conditions.

  20. Removal of Wax and Stickies from OCC by Flotation

    Energy Technology Data Exchange (ETDEWEB)

    M. R. Doshi; J. Dyer

    2000-01-31

    Laboratory research indicates that wax is amenable to removal by froth flotation provided it is free or detached from the fiber. The only effective means, at this time, of maximizing detachment of wax is through the use of low consistency pulping at temperatures above the melting point of wax. Wax removal from WCC through washing, flotation, or a combination of both was approximately 90% in these laboratory studies, indicating that not all of the wax is detached from fibers. These results were summarized in Annual Report 1, December 1, 1997 to November 30, 1998. Pilot trials were conducted in which the authors simulated a conventional OCC repulping process with and without flotation. Additional aggressive washing and water clarification were also examined during the study. The inclusion of flotation in the OCC stock preparation system significantly improved the removal of wax spots and extractable material from the furnish. Based on this study, the authors predict that a compact flotation system with 2 lb surfactant/ton of fiber would improve the OCC pulp quality with regard to wax spots by 60% and would not negatively affect strength properties. Flotation losses would be in the 2-5% range. Two mill trials were conducted during the last quarter of the project. One trial was carried out at Green Bay Packaging, Green Bay, WI, and a second trial was conducted at Menasha Corporation, Otsego, MI. A 250-liter Voith Sulzer Ecocell was used to evaluate the removal of wax and stickies from the OCC processing systems at these two mills. The inclusion of flotation in the OCC stock preparation system significantly improved the removal of wax spots from the furnish. The data indicate that flotation was more effective in removing wax and stickies than reverse cleaners. The mill trials have demonstrated that flotation can be substituted for or replace existing reverse cleaning systems and, in some cases, can replace dispersion systems. In this manner, the use of flotation can

  1. SURFACTANT SPRAY: A NOVEL TECHNOLOGY TO IMPROVE FLOTATION DEINKING PERFORMANCE

    Energy Technology Data Exchange (ETDEWEB)

    Yulin Deng; Junyong Zhu

    2004-01-31

    Based on the fundamental understanding of ink removal and fiber loss mechanism in flotation deinking process, we developed this innovative technology using surfactant spray to improve the ink removal efficiency, reduce the water and fiber loss, reduce the chemical consumption and carry over in the flotation deinking. The innovative flotation deinking process uses a spray to deliver the frothing agent during flotation deinking to control several key process variables. The spray can control the foam stability and structure and modify the fluid dynamics to reduce the fibers entrapped in the froth layer. The froth formed at the top part of the flotation column will act as a physical filter to prevent the penetration of frothing agent into the pulp suspension to eliminate fiber contamination and unfavorable deinking surface chemistry modification due to surfactant adsorption on the fiber surface. Because of the filter effect, frothing agents will be better utilized. Under the sponsorships of the US Dept. of Energy (DOE) and the member companies of the Institute of Paper Science and Technology, we studied the chem-mechanical mechanism of surfactant spray for flotation deinking using different furnishes, chemicals, and flotation devices in the past four years. In the final year of the project, we successfully conducted mill trials at Abitibi-Consolidated, Inc., Snowflake paper recycling operation of 100% mixture of ONP/OMG. Results from laboratory, pilot-plant and mill trials indicated that surfactant spray technology can significantly reduce fiber loss in flotation deinking. It can be concluded that paper industry can profit greatly when this technology is commercialized in flotation deinking mills.

  2. Steam-frothing of milk for coffee

    DEFF Research Database (Denmark)

    Münchow, Morten; Jørgensen, Leif; Amigo Rubio, Jose Manuel

    2015-01-01

    A method for evaluation of the foaming properties of steam-frothed milk, based on image analysis (feature extraction) carried out on a video taken immediately after foam formation, was developed. The method was shown to be able to analyse steam-frothed milk made using a conventional espresso...... machine, such as commonly used by baristas. Samples of milk, processed in a commercial dairy plant, were made with varying fat (0.5%, 0.9%, 1.5%, 2.6%, 3.5%) or protein (3.0%, 3.4%. 3.8%) content and analysed using the developed method. Increased protein content was shown to cause a delay in the formation...

  3. Method for enhancing selectivity and recovery in the fractional flotation of particles in a flotation column

    Energy Technology Data Exchange (ETDEWEB)

    Klunder, Edgar B. (Bethel Park, PA)

    2011-08-09

    The method relates to particle separation from a feed stream. The feed stream is injected directly into the froth zone of a vertical flotation column in the presence of a counter-current reflux stream. A froth breaker generates a reflux stream and a concentrate stream, and the reflux stream is injected into the froth zone to mix with the interstitial liquid between bubbles in the froth zone. Counter-current flow between the plurality of bubbles and the interstitial liquid facilitates the attachment of higher hydrophobicity particles to bubble surfaces as lower hydrophobicity particles detach. The height of the feed stream injection and the reflux ratio may be varied in order to optimize the concentrate or tailing stream recoveries desired based on existing operating conditions.

  4. PURIFICATION OF WHITE WATERS BY SELECTIVE FLOTATION

    Directory of Open Access Journals (Sweden)

    Antti Haapala

    2010-08-01

    Full Text Available Removal of detrimental contaminants from paper machine circulation waters is known to benefit process runnability and paper quality. The applicability of selective flotation to remove substances of a hydrophobic nature from paper machine circulation waters was investigated in laboratory-scale experiments. The separation efficiency of ink, stickies, and wood extractives was studied by using a flotation scheme in which the froth was generated by the white water’s inherent surface active components without any chemical addition. The removal efficiency of detrimental contaminants was considered in relation to total losses of solid materials. The results showed that while not all white waters were able to produce stabile froth, those that generated froth also exhibited substantial separation of contaminants in the froth. With a moderate removal of 10% of total solids from white waters, removal of 45% of stickies, 27% of ink, and 20 to 50% of wood extractives was observed. Higher removal of contaminants resulted in solids losses at levels that are not economically feasible in paper production. The results showed that selective white water flotation can have beneficial results for papermaking processes.

  5. Flotation kinetic constants of two Colombian coals’ vitrinite maceral

    OpenAIRE

    2010-01-01

    Vitrinite maceral flotation kinetic constants are important in designing flotation columns to be used in separating this maceral group. This work shows the effect of pH, air speed and froth concentration on vitrinite maceral flotation kinetic constants by using two Colombian bituminous coals: El Cerrejón (Guajira) and La Jagua (Cesar). A 5 m high pilot-scale flotation column was used in all runs. The samples were processed using 4-10 pH, 0.7-2.1 cm/s air speed and 2-6 ml/kg of coal fro...

  6. Chemical Deinking Flotation Efficiency Of Coloured Toner

    Directory of Open Access Journals (Sweden)

    Zeljka Barbaric-Mikocevic

    2009-11-01

    Full Text Available Recycling of paper printed with colour laser printer xerox phaser 7700 has been investigated in this work. The recycling was performed by chemical deinking with double stage flotation with the usage of anion surfactant. Froths collected by flotation were re-floated in purpose to increase the usage of fibers. The efficiency of first flotation of magenta particles (98.3%, cyan (96.9% and carbon ones (91.5% was calculated from results of the image analysis method. The same method was not effective for the identification of the yellow toner particles. The particle size is important characteristic for flotation efficiency. The efficiency of the first flotation is the best for smallest particles (magenta and for them the second flotation is unnecessary, while for bigger toner particles (cyan, carbon second flotation is desirable. The efficiency of second (abf flotation as a function of each colour (cyan 78.0%, magenta 58.6% and carbon 61.4% of particle number detected by image analysis method has shown that double stage flotation is successful method of improving the usage of fibres in recycling process.

  7. Chemical Deinking Flotation Efficiency Of Coloured Toner

    Directory of Open Access Journals (Sweden)

    Višnja Mikac Dadić

    2009-01-01

    Full Text Available Recycling of paper printed with colour laser printer xerox phaser 7700 has been investigated in this work. The recycling was performed by chemical deinking with double stage flotation with the usage of anion surfactant. Froths collected by flotation were re-floated in purpose to increase the usage of fibers. The efficiency of first flotation of magenta particles (98.3%, cyan (96.9% and carbon ones (91.5% was calculated from results of the image analysis method. The same method was not effective for the identification of the yellow toner particles. The particle size is important characteristic for flotation efficiency. The efficiency of the first flotation is the best for smallest particles (magenta and for them the second flotation is unnecessary, while for bigger toner particles (cyan, carbon second flotation is desirable. The efficiency of second (abf flotation as a function of each colour (cyan 78.0%, magenta 58.6% and carbon 61.4% of particle number detected by image analysis method has shown that double stage flotation is successful method of improving the usage of fibers in recycling process.

  8. Selective separation of virgin and post-consumer polymers (PET and PVC) by flotation method.

    Science.gov (United States)

    Burat, Firat; Güney, Ali; Olgaç Kangal, M

    2009-06-01

    More and more polymer wastes are generated by industry and householders today. Recycling is an important process to reduce the amount of waste resulting from human activities. Currently, recycling technologies use relatively homogeneous polymers because hand-sorting waste is costly. Many promising technologies are being investigated for separating mixed thermoplastics, but they are still uneconomical and unreliable. At present, most waste polymers cause serious environmental problems. Burning polymers for recycling is not practiced since poisonous gases are released during the burning process. Particularly, polyvinyl chloride (PVC) materials among waste polymers generate hazardous HCl gas, dioxins containing Cl, etc., which lead to air pollution and shorten the life of the incinerator. In addition, they make other polymers difficult to recycle. Both polyethylene terephthalate (PET) and PVC have densities of 1.30-1.35g /cm(3) and cannot be separated using conventional gravity separation techniques. For this reason, polymer recycling needs new techniques. Among these techniques, froth flotation, which is also used in mineral processing, can be useful because of its low cost and simplicity. The main objective of this research is to recycle PET and PVC selectively from post-consumer polymer wastes and virgin polymers by using froth flotation. According to the results, all PVC particles were floated with 98.8% efficiency in virgin polymer separation while PET particles were obtained with 99.7% purity and 57.0% efficiency in post-consumer polymer separation.

  9. Effect of foamability index of short chain alkyl amines on flotation of quartz

    Directory of Open Access Journals (Sweden)

    Szczerkowska Sabina

    2016-01-01

    Full Text Available Amines can be used for flotation of various minerals, especially quartz. The flotation efficiency of quartz depends on the amine type and dose. It was proved that the shorter alkyl amine, higher amine concentration has to be used to recover quartz at the same level. In flotation amines play a role of both collectors and frothers. The ability of a amine to collect particles can be expressed in the form of contact angle, while the foaming properties by different parameters including dynamic foamability index (DFI and critical coalescence concentration (CCC. Determination of DFI and CCC requires advanced techniques and methods. Therefore, in this paper a rapid and facile method for determination of foaming properties of amines and also other surfactants was used. It was based on measuring the initial foam and froth heights in a conventional flotation machine at different concentrations of surfactants. The foam height-concentration curve was described by utilizing an empirical equation which was based on one-adjustable parameter called the foamability index (FI. In this work the foamability index was determined for butylamine (ButNH2, hexylamine (HexNH2 and octylamine (OctNH2 as examples of short chain alkyl amines. The determined foamability indices were 92, 12 and 4 mg/dm3 for ButNH2, HexNH2 and OctNH2, respectively. It was shown that when the flotation results of quartz were presented in the form of recovery versus normalized amine concentration in relation to the foamability index (c/FI, all the experimental data points converged to one curve. It indicates that amines act similarly but at different concentrations expressed as FI. The foamability index seems to be a useful parameter for characterizing any flotation frother.

  10. Column flotation

    Energy Technology Data Exchange (ETDEWEB)

    Kohmuench, J.N.; Norrgran, D.A.; Luttrell, E.; Luttrell, G.H. [Virginia Tech. (United States)

    2008-04-15

    Over the last decade, column flotation has been recognised in the industry to be most efficient and economical means of recovering fine coal while maximizing product grade. When designed properly, flotation columns provide a high combustible recovery while maintaining a low product ash. The paper looks at the benefits of using column flotation for fine coal recovery. 2 refs., 5 figs.

  11. A comparison study of column flotation technologies for cleaning Illinois coal. Final technical report, September 1, 1993--November 30, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Honaker, R.Q.; Paul, B.C.

    1994-12-31

    Six commercially-available column technologies were compared on the basis of their separation performance, throughput capacity and operational characteristics for treating Illinois Basin coal fines. The flotation column technologies included in this study were the Jameson Cell, Flotaire, Turboair, Packed-Column, Microcel and the Canadian Column. The coal samples treated in this study were a {minus}100 mesh flotation feed slurry, a {minus}40 mesh coal, and a refuse pond coal sample. This investigation found that the Packed Column, Jameson Cell, and Microcel are the best flotation columns for cleaning the Illinois Basin coals treated in this study. The Packed-Column was found to provide superior selectivity, although requiring the highest amount of air and frother concentration. The superior performance is believed to be related to the extensive reflux action and selective detachment mechanism that are more prevalent in the Packed-Column due to its unique ability to support a full froth column. Among the conventional open columns, the Microcel provided the best selectivity, most likely due to its lower aeration requirement which results in a more plug-flow environment within the cell. Both the Packed-Column and the Microcel appeared to have nearly equal throughput capacities. The Jameson Cell, which also has a relatively high throughput capacity, was found to require the least amount of frother while supplying a self-inducing air system. Another important finding of this investigation is that the traditional release analysis procedure is inadequate for predicting the optimum performance of advanced froth flotation processes and, thus, requires further investigation.

  12. Column flotation of bitumen at Fort Hills

    Energy Technology Data Exchange (ETDEWEB)

    Lizama, H.M. [Teck Cominco, Vancouver, BC (Canada); Romero, D. [UTS Energy Corp., Calgary, AB (Canada); Armour, M. [Petro-Canada, Calgary, AB (Canada)

    2008-05-15

    Flotation columns are used by mineral processors to separate mineral species. The separation is based on the premise that different mineral particles have different surface hydrophobicities. There are 2 carrier phases, notably air bubbles moving up and aqueous pulp moving down. Hydrophobic particles predominantly adhere to rising air bubbles and form a froth, while hydrophilic particles remain in aqueous suspension and flow down and out the bottom of the column. This paper described a demonstration plant near Fort McMurray where bitumen extraction was tested. The plant included 2 columns for bitumen flotation. Oil sands material was passed through a roll sizer and fed to a countercurrent drum separator, where it was mixed with water at 75 degrees C. Column data from the demonstration plant provided the opportunity to examine the separation behaviour during flotation of bitumen. The bitumen grade was described only in terms of bitumen content and solids content in order to simplify the interpretation of the bitumen flotation data. Bitumen/solids separation in the first column was successful at 50 to 60 degrees C, with feeds having bitumen grades between 1 and 19 per cent, and where the solids had about 60 per cent fines. Bitumen/solids separation did not occur in the second column at 50 to 60 degrees C, with feeds having bitumen grades between 8 and 63 per cent, and where the solids had about 90 per cent fines. The lack of separation was probably due to high solids entrainment in the flotation froth. It was concluded that bitumen column flotation data can be analyzed and interpreted by adopting mineral processing principles. Bitumen/solids separation can be evaluated and predicted by plotting solids recovery as a function of bitumen recovery. 7 refs., 1 tab., 6 figs.

  13. Self lubrication of bitumen froth in pipelines

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, D.D. [Univ. of Minnesota, Minneapolis, MN (United States)

    1997-12-31

    In this paper I will review the main properties of water lubricated pipelines and explain some new features which have emerged from studies of self-lubrication of Syncrudes` bitumen froth. When heavy oils are lubricated with water, the water and oil are continuously injected into a pipeline and the water is stable when in a lubricating sheath around the oil core. In the case of bitumen froth obtained from the Alberta tar sands, the water is dispersed in the bitumen and it is liberated at the wall under shear; water injection is not necessary because the froth is self-lubricating.

  14. Effect of particle size on the froth floatation of Sokoto phosphate ore

    Directory of Open Access Journals (Sweden)

    U.A. Hassan

    2016-06-01

    Full Text Available Effect of particle size on the froth floatation of Sokoto phosphate ore for its beneficiation has been investigated and established. The research has been conducted using various reagents, pH(s at different sieve size fractions. Bench scale flotation tests were carried out on -250+180μm, -180+106μm, -106+75μm, -75+45μm and -45+38μm particle size fractions after screening in order to determine the optimum flotation feed size distribution using 1 liter Denver flotation cell. The results of the scoping flotation studies using a conditioning Pulp Density of 60%Solids, pH9, 800g/t reagent dosage for AERO704 Promoter (Fatty Acid and flotation pulp density of 28.5% Solids show that +106μm particle size gave the highest assay content of 20.4% P2O5 with a recovery of 76.2% compared to +38μm (19.9%P2O5 and recovery of 43.2% and +180μm (19.4%P2O5 and 24.1% recovery in their floats (concentrates but with no perfect separation as the tailings fraction also contained similar grades with slight differences.

  15. Drift flux modelling for a two-phase system in a flotation column

    Energy Technology Data Exchange (ETDEWEB)

    Vandenberghe, J.; Choung, J.; Xu, Z.; Masliyah, J. [Alberta Univ., Edmonton, AB (Canada). Dept. of Chemical and Materials Engineering

    2005-04-01

    Mineral and coal industries use flotation columns to improve recovery, upgrade products, save energy and reduce scale. Flotation columns are a proven process equipment that are adaptable to computer process control and offer flexible operation. Once gas is introduced to the bottom of the flotation column, bubbles form and rise throughout the pulp. Hydrophobic particles in the pulp attache to the bubbles, making the density of the bubble particle aggregates less than that of the medium. The bubble zone and the froth zone are the 2 main zones of a flotation column. This study applied the drift flux analysis to a wide range of operating conditions of a two-phase system column in order develop a better empirical relation that can predict the bubbly and froth zone characteristics. Tests were performed with process water taken from a bitumen extraction process at Syncrude Canada Limited with aqueous solutions having low concentrations of methyl isobutyl carbinol at 7.8 or 15.5 ppm. A new correlation for the drift flux system characteristic curve was discovered in this study. The new correlation is applicable for a bubble Reynolds number range of 5 to 70. The numerical equation for this correlation was presented. The bubble and froth zones have different hydrodynamics. Therefore, the method for calculating the Reynolds number in the bubble zone may not be suitable for the froth zone. Therefore, a new equation was proposed to accommodate a wider operating range. 16 refs., 1 tab., 13 figs.

  16. Remediation of metal-contaminated urban soil using flotation technique.

    Science.gov (United States)

    Dermont, G; Bergeron, M; Richer-Laflèche, M; Mercier, G

    2010-02-01

    A soil washing process using froth flotation technique was evaluated for the removal of arsenic, cadmium, copper, lead, and zinc from a highly contaminated urban soil (brownfield) after crushing of the particle-size fractions >250microm. The metal contaminants were in particulate forms and distributed in all the particle-size fractions. The particle-by-particle study with SEM-EDS showed that Zn was mainly present as sphalerite (ZnS), whereas Cu and Pb were mainly speciated as various oxide/carbonate compounds. The influence of surfactant collector type (non-ionic and anionic), collector dosage, pulp pH, a chemical activation step (sulfidization), particle size, and process time on metal removal efficiency and flotation selectivity was studied. Satisfactory results in metal recovery (42-52%), flotation selectivity (concentration factor>2.5), and volume reduction (>80%) were obtained with anionic collector (potassium amyl xanthate). The transportation mechanisms involved in the separation process (i.e., the true flotation and the mechanical entrainment) were evaluated by the pulp chemistry, the metal speciation, the metal distribution in the particle-size fractions, and the separation selectivity indices of Zn/Ca and Zn/Fe. The investigations showed that a great proportion of metal-containing particles were recovered in the froth layer by entrainment mechanism rather than by true flotation process. The non-selective entrainment mechanism of the fine particles (flotation selectivity drop, especially with a long flotation time (>5 min) and when a high collector dose is used. The intermediate particle-size fraction (20-125 microm) showed the best flotation selectivity. Copyright 2009 Elsevier B.V. All rights reserved.

  17. Improved flotation performance of hematite fines using citric acid as a dispersant

    Science.gov (United States)

    Luo, Xi-mei; Yin, Wan-zhong; Sun, Chuan-yao; Wang, Nai-ling; Ma, Ying-qiang; Wang, Yun-fan

    2016-10-01

    In this study, citric acid was used as a dispersant to improve the flotation performance of hematite fines. The effect and mechanism of citric acid on the reverse flotation of hematite fines were investigated by flotation tests, sedimentation experiments, scanning electron microscopy (SEM), zeta-potential measurements, and X-ray photoelectron spectroscopy (XPS). The results of SEM analysis and flotation tests reveal that a strong heterocoagulation in the form of slime coating or coagulation in hematite fine slurry affects the beneficiation of hematite ores by froth flotation. The addition of a small amount of citric acid (less than 300 g/t) favorably affects the reverse flotation of hematite fines by improving particle dispersion. The results of sedimentation experiments, zeta-potential measurements, and XPS measurements demonstrate that citric acid adsorbs onto hematite and quartz surfaces via hydrogen bonding, thereby reducing the zeta potentials of mineral surfaces, strengthening the electrical double-layer repulsion between mineral particles, and dispersing the pulp particles.

  18. Flotation Bubble Delineation Based on Harris Corner Detection and Local Gray Value Minima

    Directory of Open Access Journals (Sweden)

    Weixing Wang

    2015-03-01

    Full Text Available Froth image segmentation is an important and basic part in an online froth monitoring system in mineral processing. The fast and accurate bubble delineation in a froth image is significant for the subsequent froth surface characterization. This paper proposes a froth image segmentation method combining image classification and image segmentation. In the method, an improved Harris corner detection algorithm is applied to classify froth images first. Then, for each class, the images are segmented by automatically choosing the corresponding parameters for identifying bubble edge points through extracting the local gray value minima. Finally, on the basis of the edge points, the bubbles are delineated by using a number of post-processing functions. Compared with the widely used Watershed algorithm and others for a number of lead zinc froth images in a flotation plant, the new method (algorithm can alleviate the over-segmentation problem effectively. The experimental results show that the new method can produce good bubble delineation results automatically. In addition, its processing speed can also meet the online measurement requirements.

  19. FLOTATION DE-INKING OF 50% ONP/ 50% OMG RECOVERED PAPERS MIXTURES USING NONIONIC SURFACTANT, SOAP, AND SURFACTANT/SOAP BLENDS

    Directory of Open Access Journals (Sweden)

    Jeremy Allix

    2010-11-01

    Full Text Available A laboratory flotation column equipped with Venturi aerators and an adjustable froth removal system was used to study the effect of calcium soap and a mixture of calcium soap/alkyl phenol ethoxylate surfactant on ink and fibres transfer during flotation de-inking of a 50% old newprint (ONP / 50% old magazines (OMG recovered papers mixture. Mass transport phenomena determining the yield of the flotation process were interpreted using model equations describing particle removal in terms of flotation, entrainment, and drainage in the froth. A decrease in the ink and mineral fillers flotation rate constant, drainage through the froth, and in fibre entrainment was observed when increasing the surfactant concentration. These trends were consistent with the typical dispersing action of the studied nonionic surfactant. An opposite effect on ink and fillers was observed when using calcium soap alone, and the increase in the flotation rate constant and drainage through the froth were consistent with the collecting and defoaming action of the calcium soap. Moreover, fibre entrainment decreased when increasing the soap concentration. The study of the surfactant/soap mixture highlighted the absence of synergy between the calcium soap and the surfactant.

  20. The jet flotation column control system

    Energy Technology Data Exchange (ETDEWEB)

    Xu Zhiqiang; Ming Shangzhi; Liu Lijian; Huangfu Jinghua; Huo Sen; Zhang Rongzeng [China Univ. of Mining and Technology, Beijing (China). Mineral Processing Dept.; Yang Hongjun [Hebi Coal Mine Administrative (China)

    1998-12-31

    Compared with the conventional mechanical flotation column, the jet flotation column has the advantages of high selectivity of separation, low investment and production cost, low floor space requirement, low dosage of reagent, easy control; it is more suitable to process fine particles. Recently, many new types of flotation columns have been developed with new methods. Mineral Processing Dept., China University of Mining and Technology (Beijing) designed an aerated, double-jet flotation column in the lab and the industrial trial will be put into operation. One of the significant characteristics of the new type of flotation column is high selectivity of separation, fast bubble mineralization speed. As it is sensitive to various factors, a control system for flotation column has been developed to stabilize the working condition, and this set of control system has been operated in the lab experiment.

  1. Separation and recovery of thermoplastics by froth floatation

    Energy Technology Data Exchange (ETDEWEB)

    Karvelas, D. E.; Jody, B. J.; Pomykala, J., Jr.; Daniels, E. J.

    1999-10-22

    This paper describes efforts by Argonne National Laboratory to develop a froth flotation process for separating and recovering plastics from mixed plastics waste streams generated from shredding obsolete appliances and automobiles. A process for recovering and separating equivalent-density ABS and HIPS from obsolete appliances was developed and pilot-tested with a through-put of 1,250 lbs/hr. The basic process is outlined; unit operations and equipment are discussed, and material balances are presented. The resulting ABS product was analyzed and its physical and mechanical properties were established. Its properties resembled those of virgin, mid-grade ABS that is commercially sold today and is widely used by the automotive industry. Injection-molding tests were also conducted by automotive-components suppliers, using the 100% recovered ABS. Headlamp back-cans and automotive ventilation-system duct components were injection molded and the results showed that the recovered ABS met the specifications for these applications. These results confirmed that the recovered ABS can be used as a substitute for virgin plastic materials for molding highly complex automotive component designs, and in parts for other durable goods. Economic analysis of a commercial-scale system was also performed using manufacturers' equipment quotes and operating data from the pilot plant, and it predicts a simple payback of less than 2 years for plants producing about 850 tons per year of ABS.

  2. Dolomite flotation of high magnesium phosphate ores using fatty acid soap collectors

    Science.gov (United States)

    Gu, Zhengxing

    The separation of dolomite from apatite has been recognized as one of the most difficult subjects in mineral processing due to the similarities in their physiochemical properties. In this study, selective surfactants were used with a fatty acid soap collector to improve the flotation performance of separating dolomite from high magnesium phosphate ores. Three surfactants, diethyl phthalate (DP), Tween-80 (TW) and derivative of sulfonate salt (DSS1) were used. Hallimond cell flotation was conducted using pure dolomite sample to determine the effects of various factors including dosages, particle size, Ca2+ ions and slimes on the dolomite flotation recovery. The results showed that the surfactants can significantly improve dolomite flotation performance by increasing collecting ability and tolerating the effect of calcium ions and slime contents. The stirrer-tank cell batch flotation tests were carried out using two natural high magnesium phosphate ore samples containing 3.3% and 1.5% MgO. The test results showed that the surfactant DP could improve dolomite flotation at low dosages, and DSS1 could enhance the separation of dolomite from phosphate by improving both collecting ability and flotation selectivity. When 10% of DSS1 was used with the fatty acid soap as collector, at least 10% more dolomite can be removed with less P2O5 loss. The effectiveness of the surfactant DSS1 in enhancing dolomite flotation was further demonstrated in modified packed column flotation with natural dolomitic phosphate ore sample. The addition of the surfactant DSS1 into fatty acid soap collector could improve its frothability and froth stability, and reduce the bubble size. It has been found that the dolomite flotation performance has a close relationship with the frothability and froth stability of the collector.

  3. Possibilities of raising the rate of fine coal flotation

    Energy Technology Data Exchange (ETDEWEB)

    Rubinstein, J.B.; Molchanov, A.E.; Chanturiya, V.A.; Guzenko, A.I. [Institute of Solid Fossil Fuels Preparation, Moscow (Russian Federation). Department of Flotation Equipment and Technological Processes Optimization

    1995-08-01

    The physical and chemical properties of coal particles change after fine grinding. A series of tests with narrow size fractions shows their floatability and the effect of fines content on the flotation response. Floatability distribution functions obtained using different reagents show that the flocculation-flotation method and flotation columns are highly efficient for upgrading coal. The methods include selective coagulation, selective flocculation, and oil agglomeration. For the flocculation-flotation process using latex (200-300 g/t), the concentrate ash was reduced by 2-3 percent, while tailings ash increased by 6-8 percent compared to conventional flotation. 11 refs., 7 figs., 2 tabs.

  4. Enhanced column flotation performance for fine coal cleaning

    Energy Technology Data Exchange (ETDEWEB)

    Honaker, R.Q.; Mohanty, M.K. [Southern Illinois University at Carbondale, Carbondale, IL (United States). Dept. of Mining Engineering

    1996-09-01

    Experimental and theoretical results have indicated that the use of multi-stage cleaning circuits enhance the separation performance achieved by flotation columns while treating fine coal. This improvement is basically due to the excellent ability of the flotation process to float particles that contain a very small amount of hydrophobic material. Single stage treatment of a -48 mesh Illinois No. 5 coal sample found that 25% of the heavy middling in the +400 mesh size fraction were recovered to the froth concentrate, which occurred despite the use of a deep froth of 3 m. The use of a cleaner stage reduced the overall recovery of heavy middlings to approximately 10% and reduced the product ash content from 9% in the rougher stage to about 6.5% in the cleaner stage while recovering 80% of the combustible material. Subsequent treatment of the cleaner product further improved the recovery-grade curve. A similar finding was also obtained from the treatment of an Illinois No. 6 coal sample using a different flotation column. 10 refs., 9 figs., 7 tabs.

  5. Flotation as a remediation technique for heavily polluted dredged material. 1. A feasibility study.

    Science.gov (United States)

    Cauwenberg, P; Verdonckt, F; Maes, A

    1998-01-19

    The flotation behaviour of highly polluted dredged material was investigated at different pH values by mechanical agitated (Denver) flotation. Up to 80% of cadmium, copper, lead and zinc could be concentrated in the froth layer which represented only 30% of the total mass. The maximum specificity for heavy metals, defined as the concentrating factor, was obtained at pH 8-9. The maximum recovery of heavy metals on the other hand was found to be reached at elevated pH values (pH 12). In addition the specificity of the flotation process for the transition metals could be assigned to their presence as metal sulphides in the dredged material. However, the interaction with organic matter is an important factor in determining their flotability. The carbonate fraction was irrelevant for the flotation behaviour of heavy metals.

  6. Nanoparticle flotation collectors II: the role of nanoparticle hydrophobicity.

    Science.gov (United States)

    Yang, Songtao; Pelton, Robert

    2011-09-20

    The ability of polystyrene nanoparticles to facilitate the froth flotation of glass beads was correlated to the hydrophobicity of the nanoparticles. Contact angle measurements were used to probe the hydrophobicity of hydrophilic glass surfaces decorated with hydrophobic nanoparticles. Both sessile water drop advancing angles, θ(a), and attached air bubble receding angle measurements, θ(r), were performed. For glass surfaces saturated with adsorbed nanoparticles, flotation recovery, a measure of flotation efficiency, increased with increasing values of each type of contact angle. As expected, the advancing water contact angle on nanoparticle-decorated, dry glass surfaces increased with surface coverage, the area fraction of glass covered with nanoparticles. However, the nanoparticles were far more effective at raising the contact angle than the Cassie-Baxter prediction, suggesting that with higher nanoparticle coverages the water did not completely wet the glass surfaces between the nanoparticles. A series of polystyrene nanoparticles was prepared to cover a range of surface energies. Water contact angle measurements, θ(np), on smooth polymer films formed from organic solutions of dissolved nanoparticles were used to rank the nanoparticles in terms of hydrophobicity. Glass spheres were saturated with adsorbed nanoparticles and were isolated by flotation. The minimum nanoparticle water contact angle to give high flotation recovery was in the range of 51° < θ(np(min)) ≤ 85°.

  7. Coal surface control for advanced fine coal flotation

    Energy Technology Data Exchange (ETDEWEB)

    Fuerstenau, D.W.; Hanson, J.S.; Diao, J.; Harris, G.H.; De, A.; Sotillo, F. (California Univ., Berkeley, CA (United States)); Somasundaran, P.; Harris, C.C.; Vasudevan, T.; Liu, D.; Li, C. (Columbia Univ., New York, NY (United States)); Hu, W.; Zou, Y.; Chen, W. (Utah Univ., Salt Lake City, UT (United States)); Choudhry, V.; Shea, S.; Ghosh, A.; Sehgal, R. (Praxis Engineers, Inc., Milpitas, CA (United States))

    1992-03-01

    The initial goal of the research project was to develop methods of coal surface control in advanced froth flotation to achieve 90% pyritic sulfur rejection, while operating at Btu recoveries above 90% based on run-of-mine quality coal. Moreover, the technology is to concomitantly reduce the ash content significantly (to six percent or less) to provide a high-quality fuel to the boiler (ash removal also increases Btu content, which in turn decreases a coal's emission potential in terms of lbs SO{sub 2}/million Btu). (VC)

  8. Effects of oxide nanomaterials used in flotation process in wastewater treatment.

    Directory of Open Access Journals (Sweden)

    CRISTINA COVALIU

    2017-05-01

    Full Text Available Important challenges in the global water situation, mainly resulting from worldwide population growth and climate change, require novel innovative water technologies in order to ensure a supply of drinking water and reduce global water pollution. For this purpose, highly advanced nanotechnology offers new opportunities in technological developments for advanced water and wastewater technology processes. This paper presents an important method used in the wastewater treatment and in the mineral separation, named the flotation. Also, this paper presents the factors that influence the froth flotation process, such as: nanoparticle hydrophobicity, nanoparticle diameter, particle softness etc.

  9. Micro-agglomerate flotation for deep cleaning of coal. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Chander, S.; Hogg, R.

    1997-01-15

    The development of practical technologies for the deep cleaning of coal has been seriously hampered by the problems of carrying out efficient coal/mineral separations at the very fine sizes (often finer than 10 {micro}m) needed to achieve adequate liberation of the mineral matter from the coal matrix. In this investigation a hybrid process--Micro-agglomerate flotation--which is a combination of oil-agglomeration and froth flotation was studied. The basic concept is to use small quantities of oil to promote the formation of dense micro-agglomerates with minimal entrapment of water and mineral particles and to use froth flotation to separate these micro-agglomerates from the water/dispersed-mineral phase. Since the floating units will be relatively large agglomerates (30--50 {micro}m in size) rather than fine coal particles (1--10 {micro}m) the problems of froth overload and water/mineral carryover should be significantly alleviated. There are, however, complications. The process involves at least five phases: two or more solids (coal and mineral), two liquids (oil and water) and one gas (air). It is demonstrated in this study that the process is very sensitive to fluctuations in operating parameters. It is necessary to maintain precise control over the chemistry of the liquid phases as well as the agitation conditions in order to promote selectivity. Both kinetics as well as thermodynamic factors play a critical role in determining overall system response.

  10. Selective flotation of fossil resin from Western coal. Final report, July 1, 1990--May 25, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, G.F.; Miller, J.D.

    1992-05-25

    The proof-of-concept test program was designed to clarify a number of concerns that have been raised by coal companies who own the valuable resin resource. First, from laboratory bench-scale flotation experiments, a froth product from cleaner flotation containing more than 80% hexane-extractable resin at higher than 80% recovery can be produced. Pilot-plant testing was initiated to demonstrate the selective flotation of fossil resin and to establish a better confidence level in the new technology. Second, pilot-plant testing was designed to evaluate the effect and impact of random variation in slurry solids concentration and feed grade on this new selective fossil resin flotation technology. The flotation performance obtained under these industrial conditions is more realistic for process evaluation. Third, more accurate operating cost data was to be obtained for economic analysis. Fourth, sufficient quantities of the fossil resin concentrate were to be produced from the test program for evaluation by potential industrial users. Fifth, and finally, optimum levels for the operating variables were to be established. Such information was required for eventual scale-up and design of a fossil resin flotation plant. The pilot-plant proof-of-concept testing of selective resinate flotation has demonstrated that: (1) technically, the new flotation technologies discovered at the University of Utah and then improved upon by Advanced Processing Technologies, Inc. provide a highly efficient means to selectively recover fossil resin from coal. The proof-of-concept continuous flotation circuit (about 0.1 tph) resulted in fossil resin recovery with the same separation efficiency as was obtained from laboratory bench-scale testing (more than 80% recovery at about 80% concentrate grade); and (2) economically, the selective flotation process has been shown to be sufficiently profitable to justify the development of a fossil resin industry based on this new flotation process.

  11. Plant practices in fine coal column flotation

    Energy Technology Data Exchange (ETDEWEB)

    Davis, V.L. Jr.; Bethell, P.J.; Stanley, F.L. [Pittston Coal Management Co., Lebanon, VA (United States); Luttrell, G.H. [Virginia Polytechnic Institute and State Univ., Blacksburg, VA (United States). Dept. of Mining and Minerals Engineering

    1995-10-01

    Five 3 m (10 ft) diameter Microcel{trademark} flotation columns were installed at Clinchfield Coal Company`s Middle Fork preparation facility in order to reduce product ash and increase recovery and plant capacity. The Middle Fork facility is utilized for the recovery of fine coal from a feed stream that consists primarily of 1.5 mm x 0 material. The columns replaced conventional flotation cells for the treatment of the minus 150 {micro}m fraction while spirals are used to upgrade the plus 150 {micro}m material in the plant feed. The addition of the column flotation circuit resulted in an increase in plant capacity in excess of 20 percent while reducing the flotation product ash content by approximately 7 percentage points. Flotation circuit combustible recovery wa increased by 17 percentage points. This paper discusses circuit design, commissioning, and sparging system design. Circuit instrumentation, level control, reagent system control, performance comparisons with conventional flotation, and general operating procedures are also discussed.

  12. Hydrophobic Forces in Flotation

    OpenAIRE

    Pazhianur, Rajesh R

    1999-01-01

    An atomic force microscope (AFM) has been used to conduct force measurements to better understand the role of hydrophobic forces in flotation. The force measurements were conducted between a flat mineral substrate and a hydrophobic glass sphere in aqueous solutions. It is assumed that the hydrophobic glass sphere may simulate the behavior of air bubbles during flotation. The results may provide information relevant to the bubble-particle interactions occurring during flotation. The glass ...

  13. Dissolved air flotation and centrifugation as methods for oil recovery from ruptured microalgal cells.

    Science.gov (United States)

    Ghasemi Naghdi, Forough; Schenk, Peer M

    2016-10-01

    Solvent-free microalgal lipid recovery is highly desirable for safer, more sustainable and more economical microalgal oil production. Dispersed air flotation and centrifugation were evaluated for the ability to separate oil and debris from a slurry mixture of osmotically fractured Chaetoceros muelleri cells with and without utilizing collectors. Microalgal oil partially phase-separated as a top layer and partially formed an oil-in-water emulsion. Although collectors, such as sodium dodecyl sulphate enhanced selective flotation, by just adjusting the pH and cell concentration of the mixture, up to 78% of the lipids were recovered in the froth. Using centrifugation of fractured microalgal slurry resulted in removal of 60% cell debris and up to 68.5% of microalgal oil was present in the supernatant. Both methods, centrifugation and flotation provided options for separation of microalgal oil from C. muelleri slurry with similar fatty acid recoveries of 57% and 60%, respectively. Copyright © 2016. Published by Elsevier Ltd.

  14. Improved GSO Optimized ESN Soft-Sensor Model of Flotation Process Based on Multisource Heterogeneous Information Fusion

    Directory of Open Access Journals (Sweden)

    Jie-sheng Wang

    2014-01-01

    Full Text Available For predicting the key technology indicators (concentrate grade and tailings recovery rate of flotation process, an echo state network (ESN based fusion soft-sensor model optimized by the improved glowworm swarm optimization (GSO algorithm is proposed. Firstly, the color feature (saturation and brightness and texture features (angular second moment, sum entropy, inertia moment, etc. based on grey-level co-occurrence matrix (GLCM are adopted to describe the visual characteristics of the flotation froth image. Then the kernel principal component analysis (KPCA method is used to reduce the dimensionality of the high-dimensional input vector composed by the flotation froth image characteristics and process datum and extracts the nonlinear principal components in order to reduce the ESN dimension and network complex. The ESN soft-sensor model of flotation process is optimized by the GSO algorithm with congestion factor. Simulation results show that the model has better generalization and prediction accuracy to meet the online soft-sensor requirements of the real-time control in the flotation process.

  15. Improved GSO optimized ESN soft-sensor model of flotation process based on multisource heterogeneous information fusion.

    Science.gov (United States)

    Wang, Jie-sheng; Han, Shuang; Shen, Na-na

    2014-01-01

    For predicting the key technology indicators (concentrate grade and tailings recovery rate) of flotation process, an echo state network (ESN) based fusion soft-sensor model optimized by the improved glowworm swarm optimization (GSO) algorithm is proposed. Firstly, the color feature (saturation and brightness) and texture features (angular second moment, sum entropy, inertia moment, etc.) based on grey-level co-occurrence matrix (GLCM) are adopted to describe the visual characteristics of the flotation froth image. Then the kernel principal component analysis (KPCA) method is used to reduce the dimensionality of the high-dimensional input vector composed by the flotation froth image characteristics and process datum and extracts the nonlinear principal components in order to reduce the ESN dimension and network complex. The ESN soft-sensor model of flotation process is optimized by the GSO algorithm with congestion factor. Simulation results show that the model has better generalization and prediction accuracy to meet the online soft-sensor requirements of the real-time control in the flotation process.

  16. Impact of Solvents Treatment on the Wettability of Froth Solids

    Science.gov (United States)

    Yang, Fan

    The purpose of this study is to investigate the impact of solvent addition to bitumen froth on the wettability of froth solids. The wettability of solids determines the transportation/partitioning of the solids between phases, which in turn affects the solids and water rejection in a Clark hot water extraction process (CHWE). The impact of solvents treatment on the wettability of froth solids was studied using both a model system and a real bitumen froth system. The vulnerabilities of four kinds of model minerals to hydrocarbon contamination/wettability alteration in different solvents were compared and discussed by considering solvent composition and mineral types. The wettability of solids extracted from the industrial froth using different solvents was also compared. The XRD analysis on these solids confirmed the partitioning behavior of solids observed in model solids system. The results from this study indicate that the composition of paraffinic/aromatic solvent in an industrial froth treatment process could be tailor-optimized to achieve a better solids/water rejection.

  17. The use of ion flotation for detoxification of metal-contaminated waters and process effluents

    Energy Technology Data Exchange (ETDEWEB)

    Doyle, F.M.; Duyvesteyn, S.; Sreenivasarao, K. [Univ. of California, Berkeley, CA (United States). Dept. of Materials Science and Mineral Engineering

    1995-12-31

    Toxic metals entering surface or ground water from sources such as metal finishing shop spills and abandoned mines can pose a significant threat to public health and the environment. Ion flotation and similar foam separation techniques show great promise for treating dilute, metal-contaminated solutions, and could also be used to treat effluents from many minerals and metallurgical processing operations prior to discharge. In ion flotation, an appropriate collector is added to the solution to form hydrophobic complexes with the metal ions. These metal-bearing species are then removed by flotation, usually with trace addition of a frother to stabilize the foam. In an effort to better understand the underlying scientific and engineering principles that determine the performance of ion flotation, the removal of Cu(II), Pb(II), Cd(II), Cr(III) and Cr(VI) has been studied using laboratory scale flotation columns in batch mode. The effects of the superficial air velocity, solution and froth height, nature of the collector, collector:metal-ion ratio, ionic strength and several frothers at low concentrations on the flotation kinetics are reported. Finally, results are presented on methods that might allow regeneration of collector and recovery of by-product metal from the foam product.

  18. Bubble size estimation using interfacial morphological information for mineral flotation process monitoring

    Institute of Scientific and Technical Information of China (English)

    YANG Chun-hua; XU Can-hui; MU Xue-min; ZHOU Kai-jun

    2009-01-01

    To relate froth structural information with mineral flotation performance, segmentation analysis was performed on froth images characterized by fully occupied convex bubbles with white spots effect. An improved valley edge detection method was proposed to extract structural features and overcome fake white spot edges seriously affecting the segmentation performance. After preprocessing, detection template was designed based on the local minimal intensity, and a binary image containing segmented boundaries was obtained by applying logical rules, thinning and filtering. Statistical features such as bubble size were estimated for control purpose. Experimental results demonstrate that the proposed method avoids over-segmentation or ill-segmentation caused by uneven illumination, and the industrial application reveals the reliability of bubble size estimation.

  19. Removal of pyrite and trace elements from waste coal by dissolved-CO{sub 2} flotation and chelating agents. Final technical report, September 1, 1993--August 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Shiao, S.Y. [Babcock and Wilcox Co., New Orleans, LA (United States); Ho, K. [Illinois Clean Coal Inst., Carterville, IL (United States)

    1994-12-31

    The overall objective of this project was to use ultrafine bubbles generated by dissolved C0{sub 2} to recover useable fuel, and reject pyrite and other minerals from a waste coal in flotation. In addition, a chelating agent was used to remove trace metals from the froth products. Illinois No. 6 waste coal obtained from a refuse thickener of a coal cleaning circuit was used as the feed in flotation. The as-received waste coal had a top size of 2400 microns. The waste coal was ground to {minus}75 microns ({minus}200 mesh) and {minus}44 microns ({minus}325 mesh). The as-received and the ground waste coal samples were subjected to flotation. Dissolved-CO{sub 2} flotation tests were performed mainly in a 3-inch diameter by 8 feet high packed column under various test conditions. Some tests were also performed in a 2-inch diameter microbubble column for comparison. The flotation performance of the waste coal in the microbubble column was higher than that for the packed column. The packing in the packed column hindered the coal flotation. The separation efficiency of the ground coal was less than that for the asreceived coal. Flotation of the waste coal was also performed in the packed column using coarser bubbles generated by dispersed C0{sub 2} and air. The separation efficiency of the ground waste coal of 44 microns top size was higher than that for dissolved-CO{sub 2} flotation. Additives were used to modify the waste coal surfaces. Triton-X 100, a nonionic surfactant and EDTA, a chelating agent, increased the separation efficiency of the waste coal.Most of the trace metals in coal were reduced in different degrees by flotation. Triton X-100 or EDTA enhanced removal of chromium, nickel, and selenium. Applying EDTA to the froth products further removed lead significantly.

  20. Flow of gas-liquid-solid system and its application in packed flotation column

    Institute of Scientific and Technical Information of China (English)

    丁一刚; 吴元欣; 李定或

    2002-01-01

    A packed flotation column, which is packed with multiple board ripple packings, was described. Based on comprehensive steady state models, chemical reactor developed previously in chemical engineering subjects, have been extended to packed flotation column for mineral separation. The experimental results verify that tanks in series model is better than axially-dispersed plug flow model to describe flow pattern in the collection zone of column by RTD (residence time distribution), and the error of experimental data and calculated data of both models are 0.07%~0.1% and 0.18%~0.45% respectively. And, RTD of gas phase was also considered, results also show that gas in the whole column appears plug flow. The cleaning process through adding wash water in froth zone of column was described, and the effect of superficial air velocity and superficial wash water velocity on the cleaning action of froth zone were discussed. Flotation experiment for single column was conducted for phosphate ores. The recovery for P2O5 was 85.8%, and the grade was 26.8%.

  1. A comparison study of column flotation technologies for cleaning Illinois coal. [Quarterly] technical report, December 1, 1993--February 28, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Honaker, R.Q.; Paul, B.C. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Mining Engineering

    1994-06-01

    The objectives of this research project are to optimize the performance of six commercially available column technologies for the treatment of Illinois Basin coal fines and to compare their performance on the basis of the recovery-grade curve and column throughput capacity. A statistically-designed, experimental program will be conducted to optimize the critical operating performance values of each flotation column. During the previous reporting period, construction and installation of the six flotation columns were completed. The flotation feed sample that will be used for the tests in this investigation was collected from a coal preparation plant treating the Illinois No. 5 seam coal. During this reporting period, the flotation feed sample was characterized on a size-by-size basis for its ash, total sulfur, and BTU content. A release analysis was also conducted to obtain the best possible recovery versus product grade curve that can be achieved by a froth flotation process for the treatment of the Illinois No. 5 flotation feed sample. Experiments were initiated on the Jameson Cell. The preliminary results indicate that the Jameson Cell achieves a separation performance that is close to the release data. The experimental program on the Jameson Cell and the other flotation technologies will be performed during the next reporting period.

  2. ITABIRITE IRON ORE CONCENTRATION BY PNEUMATIC FLOTATION CELL

    Directory of Open Access Journals (Sweden)

    Angelo Quintiliano Nunes da Silva

    2015-06-01

    Full Text Available The main iron ore processing plants in Brazil operate through reverse cationic flotation. Many studies have been conducted in order to improve flotation efficiency by optimization process variables. The pneumatic flotation cell stands out due to the simplicity to and to the intense contact particle/bubble promoted by the pulp feeding system. In this study, laboratory scale and pilot were conducted using a sample of itabirite iron ore. The objectives are evaluating the performance of this device using low grade iron ore, and drawing a comparison with laboratory scale tests on conventional flotation cell. The results indicate the potential application of pneumatic flotation cell to the ore tested. Adjustments in the feed particle size and process optimizations can be performed on the concentrate, reaching Fe and SiO2 grades used by the industry

  3. Engineering development of advanced physical fine coal cleaning technologies: Froth flotation

    Energy Technology Data Exchange (ETDEWEB)

    1992-01-01

    The construction of the DOE POC at the OCDO facility continued through this entire quarter. By the end of the quarter approximately 90% of all of the construction had been completed. All equipment has beeninstalled, checked for mechanical and installation and operated from a local pushbutton. During this quarter a review of items to be completed for start-up was compiled. This information was then presented to the construction subcontractors and agreement was concluded that all items will be completed and operational for processing coal by February 1, 1993. There are still several items that were not on site for installation during this quarter. These items are the flocculant controls supplied by Westec Engineering, Inc., and the discharge valve for the hyperbaric filter supplied by KHD. Neither of these items will prevent start-up. The flocculants can be manually controlled and provisions are all ready provided to bypass the hyperbaric filter to the Sharpels high-G centrifuge. Both of these items are scheduled for delivery in mid-January.

  4. Three-phase gas-liquid-solid foaming bubble reactors and self-lubricated transport of bitumen froth

    Science.gov (United States)

    Mata, Clara E.

    Two distinct topics in multi-phase flow of interest of the oil industry are considered in this thesis. Studies of three-phase gas-liquid-solid foaming bubble reactors and self-lubricated transport of bitumen froth are reported. Applications of foams and foaming are found in many industrial processes such as flotation of minerals, enhanced oil recovery, drilling in oil reservoirs, and refining processes. However the physics of foaming and defoaming are not fully understood. Foams trap gas and are not desirable in some processes such as oil refining. Previously, it has been found that foaming may be strongly suppressed in a cold slit bubble reactor by fluidizing hydrophilic particles in the bubbly mixture below the foam. In this work, we fluidized hydrophobic and hydrophilic versions of two different sands in a cold slit foaming bubble reactor. We found that the hydrophobic sands suppress the foam substantially better than their hydrophilic counterparts. To study the capacity of foams to carry particles, we built a new slit foaming bubble reactor, which can be continuously fed with solid particles. Global gas, liquid, and solid holdups were measured for given gas and liquid velocities and solid flow rates. This research provides the fundamental ground work for the identification of flow types in a slit three-phase foaming bubble reactor with continuous injection of particles. Bitumen froth is produced from the oil sands of Athabasca, Canada. When transported in a pipeline, water present in the froth is released in regions of high shear (at the pipe wall). This results in a lubricating layer of water that allows bitumen froth pumping at greatly reduced pressures and hence the potential for savings in pumping energy consumption. Experimental results establishing the features of this self lubrication phenomenon are presented. The pressure gradient of lubricated flows closely follow the empirical law of Blasius for turbulent pipe flow with a constant of proportionality

  5. An Overview of Optimizing Strategies for Flotation Banks

    Directory of Open Access Journals (Sweden)

    Miguel Maldonado

    2012-10-01

    Full Text Available A flotation bank is a serial arrangement of cells. How to optimally operate a bank remains a challenge. This article reviews three reported strategies: air profiling, mass-pull (froth velocity profiling and Peak Air Recovery (PAR profiling. These are all ways of manipulating the recovery profile down a bank, which may be the property being exploited. Mathematical analysis has shown that a flat cell-by-cell recovery profile maximizes the separation of two floatable minerals for a given target bank recovery when the relative floatability is constant down the bank. Available bank survey data are analyzed with respect to recovery profiling. Possible variations on recovery profile to minimize entrainment are discussed.

  6. Coal surface control for advanced fine coal flotation. Final report, October 1, 1988--March 31, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Fuerstenau, D.W.; Hanson, J.S.; Diao, J.; Harris, G.H.; De, A.; Sotillo, F. [California Univ., Berkeley, CA (United States); Somasundaran, P.; Harris, C.C.; Vasudevan, T.; Liu, D.; Li, C. [Columbia Univ., New York, NY (United States); Hu, W.; Zou, Y.; Chen, W. [Utah Univ., Salt Lake City, UT (United States); Choudhry, V.; Shea, S.; Ghosh, A.; Sehgal, R. [Praxis Engineers, Inc., Milpitas, CA (United States)

    1992-03-01

    The initial goal of the research project was to develop methods of coal surface control in advanced froth flotation to achieve 90% pyritic sulfur rejection, while operating at Btu recoveries above 90% based on run-of-mine quality coal. Moreover, the technology is to concomitantly reduce the ash content significantly (to six percent or less) to provide a high-quality fuel to the boiler (ash removal also increases Btu content, which in turn decreases a coal`s emission potential in terms of lbs SO{sub 2}/million Btu). (VC)

  7. Effects of impeller speed and aeration rate on flotation performance of sulphide ore

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The effects of aeration rate and impeller speed on the concentrate sulfur grade and recovery for batch flotation of a complex sulphide ore were investigated. The relationships between the water recovery and solid entrainment were discussed. It is found that the solid entrainment is linearly related to the water recovery regardless of aeration rate and impeller speed, and the higher sulfur recovery at the aeration rate of 2 and 4 L/min for the impeller speed of 1 500 r/min is considered to be the contribution of true flotation. Finally, the sulfur recovery flux is correlated with the bubble surface area flux based on the froth image at the different aeration rates and impeller speeds.

  8. Flotation of Biological Materials

    Directory of Open Access Journals (Sweden)

    George Z. Kyzas

    2014-03-01

    Full Text Available Flotation constitutes a gravity separation process, which originated from the minerals processing field. However, it has, nowadays, found several other applications, as for example in the wastewater treatment field. Concerning the necessary bubble generation method, typically dispersed-air or dissolved-air flotation was mainly used. Various types of biological materials were tested and floated efficiently, such as bacteria, fungi, yeasts, activated sludge, grape stalks, etc. Innovative processes have been studied in our Laboratory, particularly for metal ions removal, involving the initial abstraction of heavy metal ions onto a sorbent (including a biosorbent: in the first, the application of a flotation stage followed for the efficient downstream separation of metal-laden particles. The ability of microorganisms to remove metal ions from dilute aqueous solutions (as most wastewaters are is a well-known property. The second separation process, also applied effectively, was a new hybrid cell of microfiltration combined with flotation. Sustainability in this field and its significance for the chemical and process industry is commented.

  9. Beneficiation of the gold bearing ore by gravity and flotation

    Science.gov (United States)

    Gül, Alim; Kangal, Olgaç; Sirkeci, Ayhan A.; Önal, Güven

    2012-02-01

    Gold concentration usually consists of gravity separation, flotation, cyanidation, or the combination of these processes. The choice among these processes depends on the mineralogical characterization and gold content of the ore. Recently, the recovery of gold using gravity methods has gained attention because of low cost and environmentally friendly operations. In this study, gold pre-concentrates were produced by the stepwise gravity separation and flotation techniques. The Knelson concentrator and conventional flotation were employed for the recovery of gold. Gold bearing ore samples were taken from Gümüşhane Region, northern east part of Turkey. As a result of stepwise Knelson concentration experiments, a gold concentrate assaying around 620 g/t is produced with 41.4wt% recovery. On the other hand, a gold concentrate about 82 g/t is obtained with 89.9wt% recovery from a gold ore assaying 6 g/t Au by direct flotation.

  10. Beneficiation of an Indian non-coking coal by column flotation

    Institute of Scientific and Technical Information of China (English)

    N.Vasumathi; T.V.Vijaya Kumar; S.Ratchambigai; S.Subba Rao; S.Prabhakar; G.Bhaskar Raju

    2016-01-01

    Beneficiation of non-coking coal is gaining ground in India.It not only reduces the volume of inert content to be transported to the power plant and also lowers the wear in the boiler houses.For special applications such as the fuel for integrated gasification combined cycle plant (IGCC),the ash content in the coal should preferably be below 15 %.Indian coals are characterized by high inter-grown ash content mainly due to ‘drift origin’ of Gondwana formation in Permian age.This warrants fine grinding of non-coking coal in order to liberate the ash forming minerals from coal macerals.A noncoking coal sample of vitrinite type from India was ground to 44 tm (d80) and subjected to column flotation to improve its quality.The non-coking coal analyzing 34.6 % ash,26.2 % volatile matter,1.3 % moisture and 37.9 % fixed carbon could be upgraded to a concentrate/froth of 14.83 % ash at 72.18 % yield by optimizing collector and frother dosages and flotation column operating parameters,namely,froth depth,superficial feed velocity and superficial air velocity.The concentrate produced by this process is suitable as fuel for IGCC in coal-to-electricity route.

  11. Distribution behavior of collector in the desilication system of bauxite flotation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The distribution behavior of the HZB collector (a kind of long chain fatty acid) in the desilication system of bauxite flotation was studied. The results show that the collector tends towards froth products in the steps of the roughing, the first cleaning and the second cleaning, while towards the tailing product in the step of the scavenging, and in each job except scavenging the collector is mainly on the surface of solids. As for the froth product in the step of the scavenging, it is mainly in solution. To the tailing products of every step, it is mainly in the respective solutions. The collector added to the flotation system is mainly taken out by the last concentrate, by which the taken one occupies 65.2% of the whole, among which, 57.8% is by solid and 7.4% by solution, respectively. And the one by the last tail occupies 34.8% of the whole, among which, 8.8% is by solid and 26.0% by solution, respectively. The sum of the collector in the solution of the last concentrate and tailing is 33.4% of the amount of addition collector, and recycling the solutions will be in favor of decreasing the dosage of collector.

  12. Demonstration of the exponential decay law using beer froth

    Energy Technology Data Exchange (ETDEWEB)

    Leike, A. [Ludwig-Maximilians-Universitaet, Sektion Physik, Munich (Germany)]. E-mail: leike@theorie.physik.uni-muenchen.de

    2002-01-01

    The volume of beer froth decays exponentially with time. This property is used to demonstrate the exponential decay law in the classroom. The decay constant depends on the type of beer and can be used to differentiate between different beers. The analysis shows in a transparent way the techniques of data analysis commonly used in science - consistency checks of theoretical models with the data, parameter estimation and determination of confidence intervals. (author)

  13. Flotation of Chalcopyrite and Molybdenite in the Presence of Organics in Water

    Directory of Open Access Journals (Sweden)

    Maria Sinche-Gonzalez

    2016-10-01

    Full Text Available One of the water constituents that has not been investigated in great detail for potential detrimental effect on mineral flotation is organic matter. This study investigates the effect of natural organic materials contained in water, such as humic, fulvic and tannic acids, on the flotation of copper and molybdenum sulphides in alkaline conditions and in concentrations similar to those found in natural waters. Results show that copper and molybdenum grades decreased with the addition of humic, tannic and fulvic acid in that order, with a larger depression of molybdenite grade and recovery. Adsorption studies using ultraviolet (UV-visible spectroscopy and X-ray photoelectron spectrometer (XPS surface analysis confirmed that these organic materials were adsorbed on the minerals surface. Complimentary analyses of froth characteristics, particle size distribution and fine particles entrainment were also conducted to explain the cause of the negative effect of these organic materials on flotation. The flotation results were explained in terms of the decrease in the hydrophobicity of the mineral surfaces due to the adsorption of hydrophilic groups in these organic materials which then prevent bubble-particle adhesion. The larger detrimental effect of humic acid is due to its higher adsorption on the minerals, high molecular weight and carbon content compared with the other organic acids used.

  14. Flotation of PAH contaminated dredged sludge

    NARCIS (Netherlands)

    Mulleneers, H.; Roubroeks, S.; Bruning, H.; Rulkens, W.H.; Koopal, L.K.

    2000-01-01

    The applicability of dissolved air flotation to remediate contaminated sediments of "Overschie" (Rotterdam) and "Petrol Harbor" (Amsterdam) is studied. Several flotation reagents (Diesel Fuel, Montanol, Aerophine, Aerofroth) are applied to enhance the flotation efficiency. The physical chemical

  15. Recovery and grade prediction of pilot plant flotation column concentrate by a hybrid neural genetic algorithm

    Institute of Scientific and Technical Information of China (English)

    F.Nakhaei; M.R.Mosavi; A.Sam

    2013-01-01

    Today flotation column has become an acceptable means of froth flotation for a fairly broad range of applications,in particular the cleaning of sulfides.Even after having been used for several years in mineral processing plants,the full potential of the flotation column process is still not fully exploited.There is no prediction of process performance for the complete use of available control capabilities.The on-line estimation of grade usually requires a significant amount of work in maintenance and calibration of on-stream analyzers,in order to maintain good accuracy and high availability.These difficulties and the high cost of investment and maintenance of these devices have encouraged the approach of prediction of metal grade and recovery.In this paper,a new approach has been proposed for metallurgical performance prediction in flotation columns using Artificial Neural Network (ANN).Despite of the wide range of applications and flexibility of NNs,there is still no general framework or procedure through which the appropriate network for a specific task can be designed.Design and structural optimization of NNs is still strongly dependent upon the designer's experience.To mitigate this problem,a new method for the auto-design of NNs was used,based on Genetic Algorithm (GA).The new proposed method was evaluated by a case study in pilot plant flotation column at Sarcheshmeh copper plant.The chemical reagents dosage,froth height,air,wash water flow rates,gas holdup,Cu grade in the rougher feed,flotation column feed,column tail and final concentrate streams were used to the simulation by GANN.In this work,multi-layer NNs with Back Propagation (BP) algorithm with 8-17-10-2 and 8-13-6-2 arrangements have been applied to predict the Cu and Mo grades and recoveries,respectively.The correlation coefficient (R) values for the testing sets for Cu and Mo grades were 0.93,0.94 and for their recoveries were 0.93,0.92,respectively.The results discussed in this paper indicate

  16. Synthesis of Novel Ether Thionocarbamates and Study on Their Flotation Performance for Chalcopyrite

    Directory of Open Access Journals (Sweden)

    Gang Zhao

    2016-09-01

    Full Text Available Novel ether thionocarbamates, O-butoxy isopropyl-N-ethoxycarbonyl thionocarbamate (BIPECTC and O-(2-butoxy-1-methylethoxy isopropyl-N-ethoxycarbonyl thionocarbamate (BMIPECTC, were synthesized in this study. Their collecting efficiencies in the flotation of chalcopyrite were investigated using flotation tests, adsorption measurements, ultraviolet spectra (UV and Fourier transform-infrared spectroscopy (FT-IR and density functional theory (DFT calculations. The synthesized ether thionocarbamates showed better frothing properties than methyl-isobutyl-carbinol (MIBC and stronger affinity to chalcopyrite compared with O-isopropyl-N-ethyl thionocarbamate (IPETC and O-isobutyl-N-ethoxycarbonyl thionocarbamate (IBECTC. UV spectra analysis showed that the ether thionocarbamates react with Cu2+, with the exception of Fe2+, Ni2+, Zn2+ and Pb2+. Additionally, it was further confirmed by FTIR spectra that a chemical reaction occurs between copper ion and BIPECTC and BMIPECTC. The adsorption capacity measurements revealed that chalcopyrite exhibits good adsorption ability for ether thionocarbamates at an approximate pH of 8–10, which agrees with the flotation tests. The quantum chemistry calculation results indicated that the ether thionocarbamates exhibit stronger collecting ability for copper mineral in terms of frontier molecular orbital analysis, binding model simulation with copper ions and the molecular hydrophobicity compared with IPETC and IBECTC. The computational results are in very good agreement with the experimental results.

  17. Effects of surfactant on bubble hydrodynamic behavior under flotation-related conditions in wastewater.

    Science.gov (United States)

    Li, Yanpeng; Zhu, Tingting; Liu, Yanyan; Tian, Ye; Wang, Huanran

    2012-01-01

    Bubble behavior is fundamental to the performance of froth flotation operations used in wastewater treatment processes. To fully understand and characterize bubble behavior under flotation-related conditions in wastewater, the high-speed photographic method has been employed to examine the motion of single bubbles and size distribution of bubble swarms with intermediate sizes ranging from 1 to 4 mm in the presence of surfactants in a laboratory scale flotation column. Both distilled water and synthetic municipal wastewater have been used to make solutions as well as two types of common surfactants. The instantaneous bubble motion has been recorded by a high speed camera. Subsequently, bubble trajectory, dimensions, velocity and distribution have been determined from the recorded frames using the image analysis software. The experimental results show that the addition of surfactant into wastewater has similar effects on bubble hydrodynamic behavior as in pure water (e.g., improving trajectory stabilization, dampening bubble deformation, slowing down terminal velocity, reducing bubble size and increasing the specific surface area of bubble swarm) due to the Marangoni effect. However, it is interesting to note that surfactant effects on single bubble hydrodynamics in wastewater are slightly stronger than those in pure water while surfactant effects on size parameters of bubble swarms in wastewater are significantly stronger than those in pure water. This finding suggests that besides surfactant, inorganic salts present in synthetic wastewater have an important influence on bubble dispersion.

  18. Removal of carbon constituents from hospital solid waste incinerator fly ash by column flotation.

    Science.gov (United States)

    Liu, Hanqiao; Wei, Guoxia; Zhang, Rui

    2013-01-01

    Hospital solid waste incinerator (HSWI) fly ash contains a large number of carbon constituents including powder activated carbon and unburned carbon, which are the major source of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) in fly ash. Therefore, the removal of carbon constituents could reduce PCDD/Fs in fly ash greatly. In this study, the effects of the main flotation parameters on the removal of carbon constituents were investigated, and the characteristics of the final product were evaluated. The results showed that loss on ignition (LOI) of fly ash increased from 11.1% to 31.6% during conditioning process. By optimizing the flotation parameters at slurry concentration 0.05 kg/l, kerosene dosage 12 kg/t, frother dosage 3 kg/t and air flow rate 0.06 m(3)/h, 92.7% of the carbon constituents were removed from the raw fly ash. Under these conditions, the froth product has LOI of 56.35% and calorific values of 12.5 MJ/kg, LOI in the tailings was below 5%, and the total toxic equivalent (TEQ) of PCDD/Fs decreased from 5.61 ng-TEQ/g in the raw fly ash to 1.47 ng-TEQ/g in the tailings. The results show that column flotation is a potential technology for simultaneous separation of carbon constituents and PCDD/Fs from HSWI fly ash.

  19. Dissolved air flotation and me.

    Science.gov (United States)

    Edzwald, James K

    2010-04-01

    This paper is mainly a critical review of the literature and an assessment of what we know about dissolved air flotation (DAF). A few remarks are made at the outset about the author's personal journey in DAF research, his start and its progression. DAF has been used for several decades in drinking water treatment as an alternative clarification method to sedimentation. DAF is particularly effective in treating reservoir water supplies; those supplies containing algae, natural color or natural organic matter; and those with low mineral turbidity. It is more efficient than sedimentation in removing turbidity and particles for these type supplies. Furthermore, it is more efficient in removing Giardia cysts and Cryptosporidium oocysts. In the last 20 years, fundamental models were developed that provide a basis for understanding the process, optimizing it, and integrating it into water treatment plants. The theories were tested through laboratory and pilot-plant studies. Consequently, there have been trends in which DAF pretreatment has been optimized resulting in better coagulation and a decrease in the size of flocculation tanks. In addition, the hydraulic loading rates have increased reducing the size of DAF processes. While DAF has been used mainly in conventional type water plants, there is now interest in the technology as a pretreatment step in ultrafiltration membrane plants and in desalination reverse osmosis plants. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  20. Immobilization of copper flotation waste using red mud and clinoptilolite.

    Science.gov (United States)

    Coruh, Semra

    2008-10-01

    The flash smelting process has been used in the copper industry for a number of years and has replaced most of the reverberatory applications, known as conventional copper smelting processes. Copper smelters produce large amounts of copper slag or copper flotation waste and the dumping of these quantities of copper slag causes economic, environmental and space problems. The aim of this study was to perform a laboratory investigation to assess the feasibility of immobilizing the heavy metals contained in copper flotation waste. For this purpose, samples of copper flotation waste were immobilized with relatively small proportions of red mud and large proportions of clinoptilolite. The results of laboratory leaching demonstrate that addition of red mud and clinoptilolite to the copper flotation waste drastically reduced the heavy metal content in the effluent and the red mud performed better than clinoptilolite. This study also compared the leaching behaviour of metals in copper flotation waste by short-time extraction tests such as the toxicity characteristic leaching procedure (TCLP), deionized water (DI) and field leach test (FLT). The results of leach tests showed that the results of the FLT and DI methods were close and generally lower than those of the TCLP methods.

  1. Wastewater treatment by flotation

    Directory of Open Access Journals (Sweden)

    F.P. Puget

    2000-12-01

    Full Text Available This work deals with the performance analysis of a separation set-up characterized by the ejector-hydrocyclone association, applied in the treatment of a synthetic dairy wastewater effluent. The results obtained were compared with the results from a flotation column (cylindrical body of a hydrocyclone operated both batch and continuously. As far as the experimental set-up studied in this work and the operating conditions imposed to the process, it is possible to reach a 25% decrease in the total effluent chemical oxygen demand (COD. This corresponds approximately to 60% of the COD of the material in suspension. The best results are obtained for ratios air flow rate-feed flow rate (Qair/Q L greater then 0.15 and for ratios underflow rate-overflow rate (Qu/Qo lower than 1.0.

  2. 33 CFR 183.322 - Flotation materials.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Flotation materials. 183.322 Section 183.322 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED... of 2 Horsepower or Less General § 183.322 Flotation materials. (a) Flotation materials must meet the...

  3. Reducing axial mixing in flotation columns

    Energy Technology Data Exchange (ETDEWEB)

    Al Taweel, A.M.; Ramadan, A.M. [Technical Univ. of Nova Scotia, Halifax (Canada). Chemical Engineering Dept.; Moharam, M.R.; Hassan, T.A. [Al Azhar Univ., Cairo (Egypt); El Mofty, S.M. [Cairo Univ., Giza (Egypt)

    1995-10-01

    The axial mixing characteristics of a pilot-scale flotation column were investigated with the objective of identifying means to mitigate the extent of axial mixing that adversely affects its grade/recovery performance. A wide range of design and operating conditions wa investigated and the experimental results, obtained using the dynamic response method, were analyzed using three axial mixing models. The dynamic response of the column can best be described using the axial dispersion model. The results obtained suggest that the value of the axial dispersion coefficient, E{sub L}, can be significantly reduced by judicial selection of hydrodynamic conditions and/or the use of column inserts that suppress the onset of hydrodynamic instabilities inherent to the operation of conventional flotation columns. Up to 40% reduction in the value of E{sub L} was thus obtained by using spargers that produce more uniform bubble sizes, while up to 30% reductions were obtained by controlling the residual frother concentration. 33 refs., 7 figs.

  4. Effect of solvent selection on froth treatment for mining operations

    Energy Technology Data Exchange (ETDEWEB)

    Hamza, H.A. [Natural Resources Canada, Devon, AB (Canada). CANMET Energy Technology Centre

    2003-07-01

    The heavy oil (bitumen) industry is important for the Canadian economy. The oil sands are unique to Canada and government support is crucial for continued research into the development of technologies and products which make less of an impact on the environment. This paper describes a successful collaboration between the Canada Centre for Mineral and Energy Technology (CANMET) and Shell Canada which led to the 2003 award for Advanced Separation Technologies (AST). This PowerPoint presentation reviews feeds for a naphtha solvent treatment versus a paraffinic solvent treatment. The feeds include bitumen froth, low quality bitumen emulsions, in-situ heavy oil emulsions, and bitumen. Microscope images for each of these feeds were illustrated. The typical elements of the solvent treatment process were also outlined in a flow chart. The main feature of the naphtha process is that it is well established plus it renders a product with 1.5 to 4 per cent water and 0.5 per cent solids. It needs chemical demulsifiers and no asphaltene is rejected. The main feature of the paraffinic process is that it produces a product with low water/solids content and asphaltene levels can be controlled. The process requires less solvent for pipelining because of its reduced viscosity and if offers flexibility in terms of upgrading options. The presentation listed achievements in AST by Albian Sands, TrueNorth, Canadian Natural Resources Ltd., Suncor, Syncrude, and AEC Pipelines Ltd. tabs., figs.

  5. Application of the hydrophile-lipophile balance concept to the classification of demulsifiers and bituminous froth and its components

    Energy Technology Data Exchange (ETDEWEB)

    Vander Kloet, Jana; Schramm, Laurier L.; Shelfantook, Bill [Chemistry Department, University of Calgary, Calgary, Alberta (Canada)

    2002-01-18

    The hydrophile-lipophile balance (HLB) was used to characterize several naphtha-diluted bituminous froth and bitumen phases, extracted froth components, and commercial demulsifiers used to resolve the froth emulsions. The requirements for emulsification of the diluted froth and bitumen phases could be classified by the HLB system in terms of required HLB values. Although such classification was not effective in detecting gross changes in the interfacial components of the diluted froth and bitumen phases, meaningful HLB values were obtained for the water soluble natural surfactants (HLB 16{+-}1) and asphaltenes (HLB 11{+-}1) isolated from the froth. The HLB values for three commercial demulsifiers were found to change depending on the delivery medium, from 12{+-}1 if the demulsifier was dissolved in naphtha to 7{+-}1 if the demulsifier was dissolved in water. This difference in apparent HLB may arise from differences in interfacially active components in the diluent. It appears that demulsifier components delivered in naphtha and the water-soluble natural surfactants will seek to form O/W emulsions and, therefore, act to destabilize the W/O froth emulsions. Conversely, demulsifier components delivered in water and naturally occurring asphaltenes will act to stabilize the W/O froth emulsions.

  6. Mitigating fouling in the high temperature paraffinic froth treatment process through science and serendipity

    Energy Technology Data Exchange (ETDEWEB)

    Chakrabarty, Tapantosh [Imperial Oil Resources (Canada)], email: apan.chakrabarty@esso.ca

    2010-07-01

    This work focuses on the application of high temperature paraffinic froth treatment (HT-PFT); a technique used to clean froth that results from the process of water extraction of oil sands. This technique includes the addition of a paraffinic solvent to the bitumen as a preliminary step in removing froth structures, leading to a possible fouling of the inner walls of the treatment vessels. Therefore, a fouling preventive technique consisting of three novel solutions was investigated in this work. The accumulations of fouling components were constantly monitored during the HT-PFT process using a gamma-ray densitometer. Results showed that buildups mostly consisted of inorganic solid structures held together with asphaltene. It was also shown that fluorocarbon polymer coating (FPC) proved to be the most effective additive in preventing fouling buildups, and by using fouling collectors in the vessels buildups were highly reduced downstream. In general, incorporating this preventive technique with HT-PFT was recommended.

  7. Waster water treatment with Cavitation Air Flotation (CAF) system; Tratamiento de las aguas residuales utilizando el sistema de flotacion por aire inducido (CAF)

    Energy Technology Data Exchange (ETDEWEB)

    Escofet Lugstenmann, I.

    1998-12-01

    In wastewater treatment from industries, the flotation process as physical-chemical treatment or primary treatment, based on the difference of densities of the solid-liquid suspension, is an important step for the elimination of the contaminant material, both as suspended solids and oils and greases. The Cavitation Air Flotation (CAF) system is an unique, innovative and very easy method which introduces air into the flotation system. It was created to come over the problems and limitations of more conventional techniques of Dissolved Air Flotation (DAF). (Author) 9 refs.

  8. Wemco-Leeds flotation machine. El sistema de flotacion en columna WEMCO-LEEDS

    Energy Technology Data Exchange (ETDEWEB)

    Ridriguez-Avello, A.

    1990-02-01

    Column flotation is used to achieve high grade concentrates whilst dispensing with a whole series of stages thereby considerably simplifying the process. In the case of coal, a single machine can serve to dress and wash whilst for metallic minerals, the machine can replace several washing stages following conventional dressing. Wemco has developed a column flotation system which is novel in the fact that the operation is carried out in a cell very similar to conventional cells with respect to its size and shape but which gives output figures and grades typical of this process. 17 figs., 6 tabs.

  9. Heavy metals in the products of deinking flotation of digital offset prints.

    Science.gov (United States)

    Barbaric-Mikocevic, Zeljka; Orescanin, Visnja; Bolanca, Zdenka; Lulic, Stipe; Rozic, Mirela

    2004-01-01

    This study was undertaken to investigate the suitability of applying the conventional method of chemical deinking flotation of digital offset prints and ecological implications of the disposal of digital offset prints, with special emphasis on the content of heavy metal cations. The EDXRF method was used to determine the concentrations of Pb, Zr, Sr, As, Co, Zn, Cu, Ni, Fe, Mn, Cr, V, Ti, Ca, and K cations in handsheet ashes after flotation as well as in ashes of foams separated from cellulose suspension in the flotation phase. The same method was applied to determine the concentrations of Pb, Cr, Mn, Fe, Ni, Cu, Zn, and Co in process water filtrates obtained from the cellulose suspension after flotation and in foam filtrates. Centrifuging and coagulation previously treated flotation process water, while foam filtrates were centrifuged. Concentrations of Pb, As, Sr, Zr, K, Ca, Ti, V, Cr, Mn, Fe, Cu, and Zn were determined in the sediments obtained by centrifuging process water. The trials were done with unprinted substrates without deinking chemicals, with unprinted substrates in the presence of deinking chemicals and with printed substrates in the presence of deinking chemicals. Cation analysis revealed that deinking chemicals facilitate release of cations from the substrate and their transition into process water. Concentrations of most cations in the flotation process water, in foam water as well as in the sediment of the process water of printed substrate flotation deinking were lower than those obtained by flotation of unprinted substrate suspension. Polymer particles of ElectroInk incompletely separated from cellulose fibers prevent release of cations from cellulose fibers into process water. Deinking chemicals do not affect release of cations from ElectroInk particles, so the substrate is the main source of increased concentration of cations in the water of digital offset print deinking. The major part of cations in process water is bound to the colloid

  10. Flotation as a remediation technique for heavily polluted dredged material. 2. Characterisation of flotated fractions.

    Science.gov (United States)

    Cauwenberg, P; Verdonckt, F; Maes, A

    1998-01-19

    The particle size distribution and the metal speciation of the heavy metals were investigated on dredged sediment and on the fractions obtained by mechanical agitated (Denver) flotation. The transition metal ions (cadmium, copper, lead and zinc) were flotated specifically independent of the particle size. Particle size analysis, EDTA extraction and sequential extracts indicated that during flotation a redistribution of metals occurred due to the oxidation of metal sulphides. This oxidation process was more pronounced when the flotation was performed at higher pH values and resulted in a decrease in flotation specificity.

  11. Counterflow co-flocculation flotation for water purification.

    Science.gov (United States)

    Guo, Jinlong; Wang, Yil; Li, Dapeng; Tang, Hongxiao

    2003-05-01

    A new method for potable water treatment was brought forward and studied in this research. The treatment process was named as counterflow co-flocculation flotation (CC-FF). Pilot experiment was conducted and the operational parameters were presented. The optimized operational conditions are as follows: the detention time is 6-11 min with hydraulic load of 9-16 m3/(m2 h); the recycle ratio should be no less than 8% while the distance between the inlet of source water and recycle water should be greater than 1200 mm. If the source water turbidity was lower than 100 NTU, 0.12-0.35 mmol/L Al dosage is enough to maintain efficient turbidity removal. Since the flocculation and flotation processes were carried out in the same tank, this new technique has some advantages than the conventional flocculation-flotation methods. Firstly, the microbubbles released from recycle water will participate in the flocculation of suspended particles, hence the low-density but high shear-force-resistance flocci could be formed. Secondly, the microflocci or suspended particles will be functioned as 'nucleus' during the bubble formation from air-dissolved recycle water. Thirdly, in the midsection of the tank a blanket of bubble-microfloc aggregates could be formed, which will intercept the downward-flow flocci and upward-flow bubbles efficiently, thus keep the renovation and stability of the blanket.

  12. Pico-nano bubble column flotation using static mixer-venturi tube for Pittsburgh No. 8 coal seam

    Institute of Scientific and Technical Information of China (English)

    Peng Felicia F.; Yu Xiong

    2015-01-01

    The flotation process is a particle-hydrophobic surface-based separation technique. To improve the essential flotation steps of collision and attachment probabilities, and reduce the step of detachment probabilities between air bubbles and hydrophobic particles, a selectively designed cavitation venturi tube combined with a static mixer can be used to generate very high numbers of pico and nano bubbles in a flotation column. Fully embraced by those high numbers of tiny bubbles, hydrophobic particles readily attract the tiny bubbles to their surfaces. The results of column flotation of Pittsburgh No. 8 seam coal are obtained in a 5.08 cm ID and 162 cm height flotation column equipped with a static mixer and cavitation venturi tube, using kerosene as collector and MIBC as frother. Design of the experimental procedure is combined with a statistical two-stepwise analysis to determine the optimal operating conditions for maximum recovery at a specified grade. The effect of independent variables on the responses has been explained. Combustible material recovery of 85–90% at clean coal product of 10–11%ash is obtained from feed of 29.6%ash, with a much-reduced amount of frother and collector than that used in conventional column flotation. The column flotation process utilizing pico and nano bubbles can also be extended to the lower limit and upper limit of particle size ranges, minus 75 lm and 300–600 lm, respectively, for better recovery.

  13. Physicochemical aspects of allanite flotation

    Institute of Scientific and Technical Information of China (English)

    Adam Jordens; Chris Marion; Olga Kuzmina; Kristian E.Waters

    2014-01-01

    This paper investigated the physicochemical properties of allanite, a RE-silicate, by measuring zeta potential in the absence and presence of three different flotation collectors (benzohydroxamic acid, sodium oleate and dodecylamine). This data was then verified by microflotation experiments and with bubble-particle attachment pictures. The investigated properties of allanite were com-pared to those of quartz, a common gangue mineral in many RE deposits. The results of this work indicated that only dodecylamine was able to achieve a selective separation of allanite and quartz. This was accomplished by lowering the dodecylamine dosage so that only quartz was recovered by microflotation.

  14. Method and system to remove water from coal flotation concentrates

    Energy Technology Data Exchange (ETDEWEB)

    Schouterden, E.; van de Mosselaer, F.; Straggier, C.; Schlebusch, L.; Schiele, H.; von Essen, U.

    1981-03-19

    In the process for the water removal from a coal flotation concentrate water is removed together with oil which is added after the flotation steps in a centrifuge. The oil is added to the coal flotation concentrate in an amount of 0.3 wt-% of the total solids content. The solids obtained in the centrifugate are sorted and concentrated in a secondary flotation step. Prior to the flotation step flotation agents can be added to the centrifugate. After the secondary flotation step the concentrate is introduced to a decanter or a filtering device.

  15. 胶磷矿选矿中不同植物脂肪酸的常温浮选性能%Flotation performance of plant fatty acid on collophanite at normal temperature

    Institute of Scientific and Technical Information of China (English)

    罗惠华; 汤家焰; 李成秀; 王亚运; 陈炳炎

    2013-01-01

    为了研究不同植物脂肪酸组成对胶磷矿常温浮选的影响,选取了棉油、豆油、米糠油、棕榈酸、硬脂肪酸等几种植物脂肪酸,采用气相色谱法分析了其脂肪酸的成分,利用浮选试验评价了其性能.试验结果表明,这几种植物油含有脂肪酸的成分不同,浮选性能也不同.常温下的浮选性能依次为:碘值135棉油脂肪酸>碘值110豆油脂肪酸>碘值95米糠油脂肪酸>碘值120棉油脂肪酸;浮选时,棕榈油脂肪酸与硬脂酸完全没有泡沫.植物脂肪酸捕收剂中的亚油酸/油酸比值对选别指标的影响为:比值越大,浮选效果越好.温度较低时,应选用不饱和脂肪酸特别是亚油酸和亚麻酸的含量高脂肪酸作为捕收剂.%Cottonseed fatty acid, soy fatty acid, rice bran fatty acid, palm oil fatty acid and stearic acid were selected to study how the composition of plant fatty acid effected froth flotation of collophanite at normal temperature. The froth flotation tests were conducted to research the flotation performance of plant fatty acid and its fatty acid composition was determined by gas chromatography. The results show that the composition of fatty acid and flotation performance of these several plant fatty acids are different. The floatability in unit of different vegetable fatty acid at normal temperature is iodine value 135 cottonseed fatty acid>iodine value 110 soy fatty acid>rice bran fatty acid > iodine value 120 cottonseed fatty acid. Palm oil fatty acid and stearic acid do not cause foaming in flotation process. The effect of L/O ratio in unit of different plant fatty acid on the ore dressing indexes is better for the flotation of collophanite when plant fatty acid with higher L/O ratio. So, unsaturated fatty acids especially containing linoleic acid and linolenic acid should be selected as collector when flotation temperature is relatively low.

  16. Optimizing dissolved air flotation design system

    Directory of Open Access Journals (Sweden)

    L.A. Féris

    2000-12-01

    Full Text Available Dissolved Air (Pressure Flotation-DAF, is a well-established separation process that employs micro-bubbles as a carrier phase. This work shows results concerning bubble generation at low working pressures in modified DAF-units to improve the collection of fragile coagula by bubbles. DAF of Fe (OH3 (as model was studied as a function of saturation pressure in the absence and presence of surfactants in the saturator. DAF was possible at 2 atm by lowering the air/water surface tension. This fact, which leads to substantial energy savings, was explained in terms of decreasing the "minimum" energy required for bubble nucleation and cavity in the nozzle. More, bubbles-fragile coagula attachment was improved by dividing the recycling water into two: 1 the inclined inlet to the cell (traditional and 2 inside the separation tank through a water flow inlet situated below the floating bed using a "mushroom" type diffuser. Because of the reduction observed in the degree of turbulence in the conventional collection zone, DAF performance improved yielding high precipitate recoveries.

  17. Influence of flotation cell volume and solids mass on kinetics of sulfide ore flotation

    OpenAIRE

    Plawski Michal; Bakalarz Alicja

    2016-01-01

    The paper presents studies on the influence of flotation cell capacity and mass of solids in the suspension on the flotation kinetics of sulfide copper ore. A sample of copper ore that was collected from the Polkowice Mine of KGHM Polska Miedz S.A. in Poland was used in the experiments. It was determined that neither the volume of flotation cell nor the mass of solids had influence on the type of kinetics equation of flotation. Copper-bearing minerals floated according to the second-order equ...

  18. Effects of High Pressure ORE Grinding on the Efficiency of Flotation Operations

    Science.gov (United States)

    Saramak, Daniel; Krawczykowska, Aldona; Młynarczykowska, Anna

    2014-10-01

    This article discusses issues related to the impact of the high pressure comminution process on the efficiency of the copper ore flotation operations. HPGR technology improves the efficiency of mineral resource enrichment through a better liberation of useful components from waste rock as well as more efficient comminution of the material. Research programme included the run of a laboratory flotation process for HPGR crushing products at different levels of operating pressures and moisture content. The test results showed that products of the high-pressure grinding rolls achieved better recoveries in flotation processes and showed a higher grade of useful components in the flotation concentrate, in comparison to the ball mill products. Upgrading curves have also been marked in the following arrangement: the content of useful component in concentrate the floatation recovery. All upgrading curves for HPGR products had a more favourable course in comparison to the curves of conventionally grinded ore. The results also indicate that various values of flotation recoveries have been obtained depending on the machine operating parameters (i.e. the operating pressure), and selected feed properties (moisture).

  19. Electrochemical flotation of diethyldithiocarbamate-pyrrhotite system

    Institute of Scientific and Technical Information of China (English)

    胡岳华; 戴晶平; 张芹

    2004-01-01

    Using sodium diethyldithiocarbamate as a collector the flotation behavior of pyrrhotite was investigated. The relationship between potential and pH range for pyrrhotite flotation was established. The results show that the flotation of pyrrhotite is dependent on pulp potential at certain pH values. Pyrrhotite has good floatability from pH 2 to pH 12, and poor flotability at pH>12. Cyclic voltammetry and Fourier transform infrared spectrum analysis show that the major adsorption product of DDTC on pyrrhotite is tetraethylthiuram disulfide. The intensity of Fourier transform infrared signals of tetraethylthiuram disulfide adsorbed on pyrrhotite and the anode current of a pyrrhotite electrode and flotation response of pyrrhotite are correlated with pulp potentials.

  20. Flotation control -- A multivariable stabilizer

    Energy Technology Data Exchange (ETDEWEB)

    Schubert, J.H.; Henning, R.G.D.; Hulbert, D.G.; Craig, I.K. [Mintek, Randburg (South Africa)

    1995-12-31

    This paper presents a stabilizing controller for flotation plants which uses a quasi-multivariable technique. The controller monitors all the levels in the plant, and by anticipating interactions between various parts of the plant, is able to stabilize the plant far more successfully than the normal plant control. Once stabilizing control has been achieved, optimization of the process becomes easier and more sustainable. An estimate of the improvement in metallurgical performance is made and a singular value analysis was conducted to verify that the multivariable algorithm will theoretically control better than a collection of individual PID loops. Metallurgical results are presented to show that the improvements are attainable in practice. Control by the Mintek algorithm was alternated with normal plant control, to show that the improvements are statistically significant.

  1. Foam flotation as a separation process

    Science.gov (United States)

    Currin, B. L.

    1986-01-01

    The basic principles of foam separation techniques are discussed. A review of the research concerning bubble-particle interaction and its role in the kinetics of the flotation process is given. Most of the research in this area deals with the use of theoretical models to predict the effects of bubble and particle sizes, of liquid flow, and of various forces on the aperture and retention of particles by bubbles. A discussion of fluid mechanical aspects of particle flotation is given.

  2. A comparison of anionic and cationic flotation of a siliceous phosphate rock in a column flotation cell

    Institute of Scientific and Technical Information of China (English)

    Al-Thyabat Salah; Yoon Roe-Hoan; Shin Dongcheol

    2011-01-01

    Flotation performance of a de-slimed (-150 + 53 μm)Jordanian siliceous phosphate was evaluated in a batch laboratory flotation column 100 cm high and 5 cm inside diameter. The collector used during anionic flotation was sodium oleate while an amine acetate (AEROMINE 3100C) was used for cationic flotation. Flotation comparison at different collector dosage, superficial gas velocity, and frother concentration showed that the maximum difference in performance between cationic and anionic flotation was obtained with these flotation parameters: 30 × 10 6 (mg/L) frother concentration, 250 g/tcollector concentration, and 3.4 cm/s superficial gas velocity. At these operating conditions amine (cationic) flotation gave 7% higher flotation recovery, a 6% cleaner concentrate grade, and was 6% more efficient at removing silica.

  3. The influence of reagent type on the kinetics of ultrafine coal flotation

    Science.gov (United States)

    Read, R.B.; Camp, L.R.; Summers, M.S.; Rapp, D.M.

    1989-01-01

    A kinetic study has been conducted to determine the influence of reagent type on flotation rates of ultrafine coal. Two ultrafine coal samples, the Illinois No. 5 (Springfield) and Pittsburgh No. 8, have been evaluated with various reagent types in order to derive the rate constants for coal (kc), ash (ka), and pyrite (kc). The reagents used in the study include anionic surfactants, anionic surfactant-alcohol mixtures, and frothing alcohols. In general, the surfactant-alcohol mixtures tend to float ultrafine coal at a rate three to four times faster than either pure alcohols or pure anionic surfactants. Pine oil, a mixture of terpene alcohols and hydrocarbons, was an exception to this finding; it exhibited higher rate constants than the pure aliphatic alcohols or other pure anionic surfactants studied; this may be explained by the fact that the sample of pine oil used (70% alpha-terpineol) acted as a frother/collector system similar to alcohol/kerosene. The separation efficiencies of ash and pyrite from coal, as evidenced by the ratios of kc/ka or kc/kp, tend to indicate, however, that commercially available surfactant-alcohol mixtures are not as selective as pure alcohols such as 2-ethyl-1-hexanol or methylisobutylcarbinol. Some distinct differences in various rate constants, or their ratios, were noted between the two coals studied, and are possibly attributable to surface chemistry effects. ?? 1989.

  4. Separation of oily materials in radioactive waste waters by flotation. Flotation kinetics; Separacion de materiales oleosos en aguas residuales radiactivas por flotacion. Cinetica de flotacion

    Energy Technology Data Exchange (ETDEWEB)

    Flores E, R.M.; Ortiz O, H.B. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: rosyperus@hotmail.com

    2003-07-01

    The rate of separation of oil and total cobalt in the oleaginous residual water previously treated by coagulation/flocculation with a quaternary ammonium amine (25 mgL{sup -1}) and with modified anionic polyacrylamide (1.5 mgL{sup -1}) (pH = 7, G{sub 1} = 300 s{sup -1} and G{sub 2} = 30 s{sup -1}) was determined. The experimental essays to determine the flotation kinetics, its were carried out using as operation and control parameters the air/solids relationship (G/S 0.35), pressure (P =620 kPa) and volume of air-water mixture (V = 37% of V{sub f}), obtained in previous essays, at two different pressure levels and volume of discharged mixture. The kinetic studies of flotation obtained for the flotation system with conventional air dissolved (DAF) its suggest a first order kinetics that it can be represented by the SCC model. At the same time its show that the separation of the present pollutants in the residual water is governed by the removal velocity of the oil. Meanwhile, the concentration of total Co below 1 mgL{sup -1}, on the other hand, the concentration of the {sup 60} Co at the end of the flotation process resulted smaller than 0.008 Bq/ml, as long as the one {sup 54} Mn were not detectable. (Author)

  5. Flotation kinetic constants of two Colombian coals’ vitrinite maceral

    Directory of Open Access Journals (Sweden)

    Jorge Luís Piñeres Mendoza

    2010-05-01

    0.559 min-1 at pH 5, respectively. The results showed that, generally, the best operating conditions for obtaining high vitrinite maceral kinetic constant values were having an acid medium and low air flow and froth concentration.

  6. Effect of desliming on the flotation of a complax copper ore from China

    Directory of Open Access Journals (Sweden)

    Chen Yong

    2016-01-01

    Full Text Available The complex copper oxide ore sample was taken from Deerni copper deposit, Qinghai Province of China. Batch flotation tests had been conducted to upgrade the copper concentrate by conventional amyl xanthate reagents under 73% -74 μm of the particle size; however, the unsatisfied results (Cu grade of 18.21% and recovery of 59.25% were obtained. Also there are a large amount of slimes trapped in the concentrate and high-dosages consumption of reagents, for example, more than 2.5 kg/t sodium sulfide and 1.5 kg/t sodium silicate at only one-staged roughing. Based on the analysis of the sample, most of gangues are clay, feldspar and mica, which may easy to over-grind and deteriorate the flotation process either on reagents consumption or slurry fluidity or viscosity. A hydro-cyclone had been introduced to pre-concentrate the oxide ore by scrubbing the slime before flotation, which can result obviously in reducing the dosages of sodium sulfide from 2.5 Kg/t to 1 Kg/t, and raising the grade of Cu in the concentrate from 18.21% to 26.65% at the expense of about 1% recovery of Cu. In this paper, the effects on the recovery of Cu by the different dosages of flotation reagents with or without de-sliming were studied, with the objective of determining the different effects on the functions of flotation reagents by slime during flotation.

  7. Vitrification of copper flotation waste.

    Science.gov (United States)

    Karamanov, Alexander; Aloisi, Mirko; Pelino, Mario

    2007-02-09

    The vitrification of an hazardous iron-rich waste (W), arising from slag flotation of copper production, was studied. Two glasses, containing 30wt% W were melted for 30min at 1400 degrees C. The first batch, labeled WSZ, was obtained by mixing W, blast furnace slag (S) and zeolite tuff (Z), whereas the second, labeled WG, was prepared by mixing W, glass cullet (G), sand and limestone. The glass frits showed high chemical durability, measured by the TCLP test. The crystallization of the glasses was evaluated by DTA. The crystal phases formed were identified by XRD resulting to be pyroxene and wollastonite solid solutions, magnetite and hematite. The morphology of the glass-ceramics was observed by optical and scanning electron microscopy. WSZ composition showed a high rate of bulk crystallization and resulted to be suitable for producing glass-ceramics by a short crystallization heat-treatment. WG composition showed a low crystallization rate and good sinterability; glass-ceramics were obtained by sinter-crystallization of the glass frit.

  8. Bitumen recovery from oil-sand extraction tailings: Part One: Bench-scale tests

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Y. H.; Mikhail, M. W.; Salama, A. I. A. [Canada Centre for Mineral and Energy Technology Western Research Centre, Devon, AB (Canada); Burns, B. [Suncor Energy Inc., Calgary, AB (Canada)

    1999-09-01

    Residual bitumen from extraction plant tailings were recovered in bench-scale tests using conventional froth flotation, flotation columns, air-sparged hydrocyclones, and various combinations of these techniques. A flowsheet combining the use of mechanically agitated flotation cells with a stationary separator was developed. Results indicate that this process is effective in recovering bitumen from tailings with low bitumen content. Investigation of the flotation kinetics in a batch flotation cell provided information on the relationship between retention and froth quality. The effect of operating parameters on bitumen flotation and the dispersion of bubbles and bitumen was also examined. Results suggests that properly increasing the turbulence energy level in flotation units will improve the recovery of bitumen by flotation. It is believed that that this is due to the interaction between bitumen droplets and bubbles and the increase in of liquid/air interfacial area. 3 refs., 13 figs.

  9. Identification and Modeling of Froth to Spray Transition on Sieve Trays

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The transition from froth to spray regime on sieve trays was experimentally studied in an air/water simulator with 300mm diameter. It has been found that the regime transition occurs as the clear liquid height is equal to the residual pressure drop on the trays. A convenient and accurate technique was proposed for determination of the regime transition point. Based on analysis of the transition process at a sieve hole, a new formula which can be used to correlate the experimental results was provided.

  10. Separation of Oil from Wastewater by Column Flotation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    A new type of device, a dissolved-air flotation column, was developed for separation of oily wastewater.The unique design idea of the dissolved-air flotation column is the combined use of dissolved-air flotation and column flotation.The dissolved air release occurred within the column separation system.As a potential application the column was investigated for its performance in separating emulsified oil droplets in oily wastewater.A high separation efficiency was obtained in a series of tests.The aeration performance of the bubble generator used in the dissolved-air flotation column was also studied in particular.

  11. Development of the Monolith Froth Reactor for Catalytic Wet Oxidation of CELSS Model Wastes

    Science.gov (United States)

    Abraham, Martin; Fisher, John W.

    1995-01-01

    The aqueous phase oxidation of acetic acid, used as a model compound for the treatment of CELSS (Controlled Ecological Life Support System) waste, was carried out in the monolith froth reactor which utilizes two-phase flow in the monolith channels. The catalytic oxidation of acetic acid was carried out over a Pt/Al2O3 catalyst, prepared at The University of Tulsa, at temperatures and pressures below the critical point of water. The effect of externally controllable parameters (temperature, liquid flow rate, distributor plate orifice size, pitch, and catalyst distance from the distributor plate) on the rate of acetic acid oxidation was investigated. Results indicate reaction rate increased with increasing temperature and exhibited a maximum with respect to liquid flow rate. The apparent activation energy calculated from reaction rate data was 99.7 kJ/mol. This value is similar to values reported for the oxidation of acetic acid in other systems and is comparable to intrinsic values calculated for oxidation reactions. The kinetic data were modeled using simple power law kinetics. The effect of "froth" feed system characteristics was also investigated. Results indicate that the reaction rate exhibits a maximum with respect to distributor plate orifice size, pitch, and catalyst distance from the distributor plate. Fundamental results obtained were used to extrapolate where the complete removal of acetic acid would be obtained and for the design and operation of a full scale CELSS treatment system.

  12. Coal flotation optimization using modified flotation parameters and combustible recovery in a Jameson cell

    Energy Technology Data Exchange (ETDEWEB)

    Vapur, Hueseyin; Bayat, Oktay [Cukurova University, Mining Engineering Department, Balcali, 01330 Adana (Turkey); Ucurum, Metin [Nigde University, Mining Engineering Department, 51100 Nigde (Turkey)

    2010-10-15

    This study discusses a new coal flotation optimization approach. It is conducted using modified flotation parameters and combustible recovery. The experimental work was evaluated in two stages. In the first stage, recoveries (1, 2, 3, 5 and 8 min of flotation times) of Jameson flotation operating parameters were fitted to first-order kinetic model, R = R{sub {infinity}} [1 - exp (-kt)] where R was recovery at t time, R{sub {infinity}} was ultimate recovery and k was the first-order rate constant to draw the time recovery curves in the experimental study. Two parameters, the ultimate recovery (R{sub {infinity}}) and first-order rate constant (k), were then obtained from the model to fit an experimental time recovery curve. A modified flotation rate constant (K{sub m}) defined as product of R{sub {infinity}} and k, i.e., K{sub m} = R{sub {infinity}}{sup *} k, and selectivity index (SI) defined as the ratio of the modified rate constant of coal to the modified rate constant of ash ((SI)=K{sub m} of Coal/K{sub m} of Ash), which could be collectively called ''modified flotation parameters''. It was used to determine of the sub and upper values of operation variables. In the second one, combustible recovery (%) and ash content (%) were used to optimization of the Jameson flotation variables and it was found that d{sub 80} = 0.250 mm particle size, 1/1 vegetable oil acids/kerosene ratio, 20% solids pulp density, 0.600 L/min wash water rate and 40 cm downcomer immersion dept could be used to separate efficiently coal from ash. Final concentrate was obtained with 94.83% combustible recovery and 17.86% ash content at optimum conditions after 8 min flotation time. (author)

  13. Physical cleaning of waste coal by dissolved-CO{sub 2} flotation. Final technical report, September 1, 1992--August 31, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Shiao, S.Y. [Babcock and Wilcox Co., Alliance, OH (United States)

    1993-12-31

    The coal wastes generated from coal mining operations and coal cleaning processes contain fine and ultrafine coals. Recovery of the fine/ultrafine coal from the coal wastes reduces the loss of useable fuels and the environmental impact. The objective of this project was to use dissolved-CO{sub 2} technology to generate ultrafine bubbles to separate fine/ultrafine coal from pyrite and other mineral matter in the coal wastes. The Illinois No. 6 coal waste used in the project was the underflow from a refuse thickener. The concentrations of the major trace metals are much higher than those found in Illinois Basin Coal database for Illinois No. 6 coals. Bench-scale conventional flotation tests of the waste coal were performed under various conditions using a 4-liter Wemco flotation cell. The tests were performed to determine the chemical dosages and flotation conditions used in dissolved-CO{sub 2} column flotation. The waste coal samples were subjected to dissolved-CO{sub 2} flotation in a 2-inch diameter microbubble column under various test conditions. The flotation performance as affected by each test variable was compared. For most of the tests, the Btu recovery was above 80%, the pyrite rejection was about 60%, and the ash rejection varied from about 45% to 76%. Dissolved air was used in one test for comparison. The waste coal samples were also subjected to typical microbubble flotation. As compared to microbubble flotation, the dissolved-CO{sub 2} had higher yield, higher Btu recovery, less pyrite rejection, and less ash rejection. Almost all of the major trace metals had a substantial reduction in concentration by dissolved-CO{sub 2} flotation, particularly for cadmium, chromium, nickel, and lead.

  14. 76 FR 17561 - Inflatable Personal Flotation Devices

    Science.gov (United States)

    2011-03-30

    ..., subpart 160.076 (Inflatable Recreational Personal Floatation Devices); 60 FR 32835 (June 23, 1995... Final Agency Policy'' (67 FR 48244, July 23, 2002). This rule involves personal flotation device... regarding our public dockets in the January 17, 2008 issue of the Federal Register (73 FR 3316). E....

  15. 76 FR 56294 - Inflatable Personal Flotation Devices

    Science.gov (United States)

    2011-09-13

    ... rule entitled ``Inflatable Personal Flotation Devices'' in the Federal Register (76 FR 17561). That... issues in a notice of proposed rulemaking. DATES: The direct final rule published March 30, 2011, (76 FR..., or why it would be ineffective or unacceptable without a change (76 FR 17563). This...

  16. 77 FR 19937 - Inflatable Personal Flotation Devices

    Science.gov (United States)

    2012-04-03

    ... National Technology Transfer and Advancement Act OMB Office of Management and Budget PFD Personal flotation... inflatable PFDs for youth would be available on the date the rule went into effect, would facilitate teens.... This rule will also result in better compliance with the National Technology Transfer and Advancement...

  17. Treatment of produced water: is a flotation viable process?; Tratamento da agua produzida: a flotacao e um processo viavel?

    Energy Technology Data Exchange (ETDEWEB)

    Santana, Claudia Ramos; Freitas, Andrea Goncalves Bueno de; Silva, Gabriel Francisco da; Paixao, Ana Eleonora Almeida [Universidade Federal de Sergipe (UFS), Aracaju, SE (Brazil); Oliveira, Rosivania da Paixao Silva [Fundacao de Apoio a Pesquisa e Extensao de Sergipe (FAPESE), Aracaju, SE (Brazil)

    2008-07-01

    In petroleum oil wells there comes a situation when most of the oil drilled accompanies a large amount of water. This may be due to the proper conditions of the reservoir or as a consequence of the water injection in the secondary recovery processes from the well. The amount of produced water together with oil can vary to a great extent and it frequently attains to about 50% of the drilled oil. One technique employed for the treatment of industrial effluents, mainly the oily ones which is of great interest is that of flotation. This phenomenon is being extensively used for oil removal from emulsified oils in various areas, such as that of dissolved air flotation (DAF) and the induced air flotation (IAF). The conventional flotation processes consist of the following stages: bubble gas generation (normally air) from the interior of the effluent; collision between the gas bubbles and the suspended oil drops in the water; adhesion of the gas bubbles in the oil drops and ascension of aggregate oil drops/bubbles until the surface, where the oil is removed. This work seeks to contribute for the understanding of the factors which contribute for the selection of the flotation process as one of the methods most viable for the treatment of the produced water. (author)

  18. Split and collectorless flotation to medium coking coal fines for multi-product zero waste concept

    Energy Technology Data Exchange (ETDEWEB)

    Dey, Shobhana; Bhattacharyya, K.K. [Mineral Processing Division, National Metallurgical Laboratory, Jamshedpur-831007 (India)

    2007-06-15

    The medium coking coal fines of - 0.5 mm from Jharia coal field were taken for this investigation. The release analysis of the composite coal reveals that yield is very low at 10.0% ash, about 25% at 14% ash and 50% at 17% ash level. The low yield is caused by the presence of high ash finer fraction. The size-wise ash analysis of - 0.5 mm coal indicated that - 0.5 + 0.15 mm fraction contains less ash than - 0.15 mm fraction. Thus, the composite feed was split into - 0.5 + 0.15 mm and - 0.15 mm fractions and subjected to flotation separately. The low ash bearing fraction (- 0.5 + 0.15 mm) was subjected to two stages collectorless flotation to achieve the concentrate with 10% ash. The cleaner concentrate (18.9%) with 10% ash was recovered which has an application in metallurgical industries. The concentrate of 30.2% yield with 12.5% ash could be achieved in one stage collectorless flotation which is suitable for use in coke making as sweetener. As the - 0.15 mm fraction contains relatively high ash, collector aided flotation using sodium silicate was performed to get a concentrate of 23.6% yield with about 17% ash. The blending of this product with cleaner tail obtained from - 0.5 + 0.15 mm produces about 35.0% yield with 17% ash and that can be utilized for coke making. The reject from the two fractions can be used for conventional thermal power plant or cement industries using a 23.5% ash after one stage collector aided flotation and the final tailings produced content ash of 61.6% can be used for fluidization combustion bed (FBC). This eventually leads to complete utilization of coal. (author)

  19. Engineering development of advanced physical fine coal cleaning technologies: Froth flotation. Quarterly technical progress report No. 17, August 1, 1992--December 31, 1992

    Energy Technology Data Exchange (ETDEWEB)

    1992-12-31

    The construction of the DOE POC at the OCDO facility continued through this entire quarter. By the end of the quarter approximately 90% of all of the construction had been completed. All equipment has beeninstalled, checked for mechanical and installation and operated from a local pushbutton. During this quarter a review of items to be completed for start-up was compiled. This information was then presented to the construction subcontractors and agreement was concluded that all items will be completed and operational for processing coal by February 1, 1993. There are still several items that were not on site for installation during this quarter. These items are the flocculant controls supplied by Westec Engineering, Inc., and the discharge valve for the hyperbaric filter supplied by KHD. Neither of these items will prevent start-up. The flocculants can be manually controlled and provisions are all ready provided to bypass the hyperbaric filter to the Sharpels high-G centrifuge. Both of these items are scheduled for delivery in mid-January.

  20. A Feasibility Study on ECT Monitoring of Froth Molding of Polyurethane

    Institute of Scientific and Technical Information of China (English)

    Qi CHEN; Shi LIU; Xiangyuan DONG

    2005-01-01

    This paper presents our recent experimental investigation on the feasibility of monitoring the froth molding, a special case of solidification process, of polyurethane by using electrical capacitance tomography. The major challenge is the extremely low solid density of the solidified material during the process due to the very large expansion ratio. Suitable calibration method is sought and adequate image reconstruction algorithm is applied for such a task. Different expansion modes have been observed during experiment and corresponding images reconstructed. This visualization technique clearly revealed the expansion process by a time series of images of the solid density. The test results proved the capability of electrical capacitance tomography in monitoring the expansion of polyurethane. Future ways for improvement are also suggested.

  1. Hydrogen bubble flotation of fine minerals containing calcium

    Institute of Scientific and Technical Information of China (English)

    Sun Wei; Ma Liang; Hu Yuehua; Dong Yanhong; Zhang Gang

    2011-01-01

    One characteristic of electro-flotation is the presence of micro bubbles that are well known for improving the flotation performance of fine particles.An electro-flotation method was studied with fine scheelite and fluorite particles sized into three different fractions.Experiments were performed in a modified Hallimond tube.We investigated the effects of gas holdup,particle size,and different mesh electrode apertures on mineral recovery.Flotation results show that two size fractions show increased flotation recovery as the gas holdup increases.For the sized scheelite and fluorite,the flotation effect is diverse for different sizes of the cathode aperture.Pictures of the bubbles taken by a high speed CCD were used to determine the hydrogen bubble size distribution generated as a function of collector,current density,and electrode size.The diameters of the hydrogen bubbles ranged from 12 to 117 μm in alkaline conditions.

  2. Effects of flotation therapy on relaxation and mental state

    Institute of Scientific and Technical Information of China (English)

    胡佩诚; 苏英

    2004-01-01

    @@ Flotation therapy is one of the models of Restricted Environmental Stimulation Therapy (REST). It has been studied and used in clinics in western countries for many years. According to the research results, flotation therapy can be used effectively in many ways.1 Some of the research done in China showed that flotation therapy could be helpful in the treatment of hypertension2 as well as cerebral paraplegia. It has also been observed in clinics that flotation therapy can induce deep relaxation, improve emotional states and have beneficial effects on some kinds of neurosis and psychosomatic diseases. But the effect of flotation therapy on the basic psychological and physiological function of ordinary Chinese has not been studied systemically. And there is no objective research result that has demonstrated the benefits of flotation therapy in Chinese clinics.

  3. Influence of flotation cell volume and solids mass on kinetics of sulfide ore flotation

    Directory of Open Access Journals (Sweden)

    Plawski Michal

    2016-01-01

    Full Text Available The paper presents studies on the influence of flotation cell capacity and mass of solids in the suspension on the flotation kinetics of sulfide copper ore. A sample of copper ore that was collected from the Polkowice Mine of KGHM Polska Miedz S.A. in Poland was used in the experiments. It was determined that neither the volume of flotation cell nor the mass of solids had influence on the type of kinetics equation of flotation. Copper-bearing minerals floated according to the second-order equation, while the remaining components according to the first-order equation. The kinetic rate constants and maximum recovery of the studied components decreased with increasing solids mass in the flotation cell, regardless of the capacity of the cell. The best results were obtained for tests using a 1.0 dm3 cell, while the less favorable kinetics results were observed in the test with the smallest cell of 0.75 dm3 volume. The obtained results can be helpful in choosing the most appropriate methodology of upgrading the sulfide copper ore from Poland in order to obtain the best kinetics results.

  4. The industrial practice and development of flotation column in China

    Energy Technology Data Exchange (ETDEWEB)

    Liu Jiongtian; Zhang Shuangquan [China Univ. of Mining and Technology, Xuzhou (China). Dept. of Energy Utilization and Chemical Engineering

    1997-12-31

    This paper reviewed the developing course of the flotation column since the 1960`s in China. Based on the practical data from several coal preparation plants, two types of flotation columns (the pressure aerated column and the jetting-cyclone column) were compared by their operation, performance and the reasons why they succeeded in the coal industry in China. The paper points out that the flotation column has come into commercial use and has good application prospects in China.

  5. Enhanced coal and mineral flotation by selective clay agglomeration

    Energy Technology Data Exchange (ETDEWEB)

    Tao, D.; Chen, G.L.; Fan, M.M.; Zhou, X.H.; Zhao, C.; Aron, M.; Wright, J. [University of Kentucky, Lexington, KY (United States)

    2006-07-01

    The purpose is to evaluate the performance of clay binding agents for enhancing coal and mineral flotation. Mechanical and column flotation tests were conducted on coal and potash samples. Several process parameters were examined, e.g. impeller rotation speed, binder dosage, slurry solids content, and collector dosage. The results show that the Georgia-Pacific reagents improved flotation efficiency under some process conditions, especially at higher solids percentage and higher impeller rotation speed. 26 refs., 9 figs., 3 tabs.

  6. Modelling and control of a flotation process

    Energy Technology Data Exchange (ETDEWEB)

    Ding, L.; Gustafsson, T. [Control Engineering Group, Lulea Univ. of Technology, Lulea (Sweden)

    1999-07-01

    A general description of a flotation process is given. The dynamic model of a MIMO nonlinear subprocess in flotation, i. e. the pulp levels in five compartments in series is developed and the model is verified with real data from a production plant. In order to reject constant disturbances five extra states are introduced and the model is modified. An exact linearization has been made for the non-linear model and a linear quadratic gaussian controller is proposed based on the linearized model. The simulation result shows an improved performance of the pulp level control when the set points are changed or a disturbance occur. In future the controller will be tested in production. (author)

  7. Fourier Transform Infrared Spectroscopic Studies in Flotation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Fourier transform infrared (FTIR) spectroscopy has been extensively employed in flotation research.The work done by the author and co-workers has been reported.A comparison has been made among the different FTIR spectroscopic techniques,e.g.,transmission FTIR spectroscopy,diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy,and attenuated total reflectance (ATR) FTIR spectroscopy.FTIR spectroscopy has been used to study the mechanism of interaction between the collector and the surfaces of different minerals,the mechanism of action of the depressant in improving the selectivity of flotation,and the mechanism of adsorption of the polymeric modifying reagent on mineral surfaces.The interaction between particles in mineral suspension has also been studied by FTIR spectroscopy.

  8. Effect of mineral processing wastewater on flotation of sulfide minerals

    Institute of Scientific and Technical Information of China (English)

    CHEN Jian-ming; LIU Run-qing; SUN Wei; QIU Guan-zhou

    2009-01-01

    The effects of mineral processing wastewater on sulfide minerals were investigated by flotation, infrared spectrometry and electrochemistry test. The results show that lead-concentrate water can improve the flotation of galena, while the sulfur-concentrate water has negative effect on flotation of galena compared with distilled water. The flotation behavior of pyrite is contrary to that of galena in three kinds of water. Infrared spectra indicate that the residual collector in the lead-concentrate water is beneficial to the formation of lead xanthate on the surface of galena. Electrochemistry results indicate that electrochemistry reaction on galena surface has apparent change. The anode polarization is improved and cathode polarization is depressed.

  9. Dissolved Air Flotation of arsenic adsorbent particles

    Directory of Open Access Journals (Sweden)

    M. Santander

    2015-04-01

    Full Text Available The removal of arsenic from synthetic effluent was studied using the adsorbent particle flotation technique (APF and dissolved air flotation (DAF. A sample of an iron mineral was used as adsorbent particles of arsenic, ferric chloride as coagulant, cationic polyacrylamide (NALCO 9808 as flocculants, and sodium oleate as collector. Adsorption studies to determine the pH influence, contact time, and adsorbent particles concentration on the adsorption of arsenic were carried out along with flotation studies to determine the removal efficiency of adsorbents particles. The results achieved indicate that the adsorption kinetic of arsenic is very rapid and that in range of pH’s from 2 to 7 the adsorption percentages remain constant. The equilibrium conditions were achieved in 60 minutes and about 95% of arsenic was adsorbed when used an adsorbent concentration of 2 g/L and pH 6.3. The maximum adsorption capacity of adsorbent particles was 4.96 mg/g. The mean free energy of adsorption (E was found to be 2.63 kJ/mol, which suggests physisorption. The results of the flotation studies demonstrated that when synthetic effluents with 8.9 mg/L of arsenic were treated under the following experimental conditions; 2 g/L of adsorbent particles, 120 mg/L of Fe(III, 2 mg/L of Nalco 9808, 20 mg/L of sodium oleate, and 40% of recycle ratio in the DAF, it was possible to reach 98% of arsenic removal and 6.3 NTU of residual turbidity in clarified synthetic effluent.

  10. [Assessment of schemes for sewage purification from petroleum products, by using various flotation methods].

    Science.gov (United States)

    Zabuga, G A; Filippova, T M; Sivkov, A A

    2010-01-01

    Petroleum products are the most common pollutants in petroleum refinery wastewater and are freed from the latter by flotation that is one of the most frequently applied physicochemical methods. The existing petroleum refinery OAO "Angara Petroleum Company" scheme for sewage purification from petroleum products, by using pressure flotation and proposed as a competitive purification scheme by applying electrical and impeller flotations underwent a comparative ecologoeconomic analysis. The use of electrical flotation instead of pressure flotation and that of an impeller flotation-electrical flotation system instead of a mechanical purification-pressure flotation one can considerably lower the concentration of petroleum products at the wastewater outlet into the Angara river.

  11. A fine coal circuitry study using column flotation and gravity separation. Quarterly report, 1 March 1995--31 May 1995

    Energy Technology Data Exchange (ETDEWEB)

    Honaker, R.Q. [Southern Illinois Univ., Carbondale, IL (United States); Reed, S. [Kerr-McGee Coal Corp., Oklahoma City, OK (United States)

    1995-12-31

    Column flotation provides excellent recovery of ultrafine coal while producing low ash content concentrates. However, column flotation is not efficient for treating fine coal containing significant amounts of mixed-phase particles. Fortunately, enhanced gravity separation has proved to have the ability to treat the mixed-phased particles more effectively. A disadvantage of gravity separation is that ultrafine clay particles are not easily rejected. Thus, a combination of these two technologies may provide a circuit that maximizes both the ash and sulfur rejection that can be achieved by physical coal cleaning while maintaining a high energy recovery. This project is studying the potential of using different combinations of gravity separators, i.e., a Floatex hydrosizer and a Falcon Concentrator, and a proven flotation column, which will be selected based on previous studies by the principle investigator. During this reporting period, an extensive separation performance comparison between a pilot-scale Floatex Density Separator (18{times}18-inch) and an existing spiral circuit has been conducted at Kerf-McGee Coal Preparation plan for the treatment of nominally {minus}16 mesh coal. The results indicate that the Floatex is a more efficient separation device (E{sub p}=0.12) than a conventional coal spiral (E{sub p}=0.18) for Illinois seam coals. In addition, the treatment of {minus}100 mesh Illinois No. 5 fine coal from the same plant using Falcon concentrator, column flotation (Packed-Column) and their different combinations was also evaluated. For a single operation, both Falcon concentrator and column flotation can produce a clean coal product with 90% combustible recovery and 5% ash content. In the case of the combined circuit, column flotation followed by the Falcon achieved a higher combustible recovery value (about 75%) than that obtained by the individual units while maintaining an ash content less than 3%.

  12. Experiments of Suppressing Froth in Vanadium LeachingSolution%沉钒液泡沫的消除

    Institute of Scientific and Technical Information of China (English)

    王金超; 管英富; 曾志勇

    2000-01-01

    针对酸性铵盐沉钒工艺沉淀酸性铵盐过程中沉钒液内涌起泡沫影响正常操作等问题,考察了钒渣碱比、浸出液pH值、表面张力和沉钒上层液等影响因素,并提出了相应的改进措施.%During the process of acidic precipitation of ammonium polyvanadate,serious frothing in the vanadium-leaching solution causes trouble to thenormal operation. To maintain smooth operation, the reason of severefrothing was identified to be the excess of soda used in vanadiumcontaining slag roasting. On this basis, technical measures of carefulcontrol of slag-to-alkali ratio, acidity and surface tension of leachingsolution were proposed to suppress frothing and the normal operation ofprecipitating vanadium salt was realized successfully.

  13. Selective separation of fine particles by a new flotation approach

    NARCIS (Netherlands)

    Mulleneers, H.A.E.; Koopal, L.K.; Bruning, H.; Rulkens, W.H.

    2002-01-01

    Fine particles often create problems in flotation applications. In this article a new laboratory flotation system for the selective separation of small particles was designed and tested. The device contains an active counter current sedimentation that should prevent entrainment of the fine

  14. Purification of Intact Plant Protoplasts by Flotation at 1g

    Directory of Open Access Journals (Sweden)

    John Graham

    2002-01-01

    Full Text Available From a standard plant tissue digest adjusted to a density of 1.07 g/ml, protoplasts can be harvested by flotation through a low density barrier (1.03 g/ml. The delicate nature of these bodies is suited to this flotation strategy which can be carried out at 1g.

  15. A new collector used for flotation of oxide minerals

    Institute of Scientific and Technical Information of China (English)

    LIU Wen-gang; WEI De-zhou; WANG Ben-ying; FANG Ping; WANG Xiao-hui; CUI Bao-yu

    2009-01-01

    A surfactant containing a mixed aliphatic structure, with a hydrocarbon chain and a diamine group, has proven to be collector for the flotation of quartz, calamine and calcite. And research about its collecting capability was carried out in laboratory. The test results show that the flotation recovery ascends sharply with increasing the concentration of collector. When the concentration of collector reaches 1.83×10~(-4)mol/L, the flotation recoveries of quartz, calamine and calcite get their maximum of 97.64%, 91.04% and 95.99%, respectively. The flotation recoveries of quartz, calamine and calcite rise sharply with the rise of pH. And in a wide range of pH, their flotation recoveries all exceed 90%. And in the whole flotation experiment, the flotation recovery of hematite rises with the increase of collector concentration and pH, while the maximal recovery is not more than 55%. Compared with dodecylamine, the N-dodecylethylenediamine has strong capability to quartz and calamine, while the flotation recoveries of calcite are closely. Hydrogen binding adsorption and electrostatic adsorption occur between the collector and the surface of quartz.

  16. 21 CFR 880.5550 - Alternating pressure air flotation mattress.

    Science.gov (United States)

    2010-04-01

    ... body pressure. The device is used to prevent and treat decubitus ulcers (bed sores). (b) Classification... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Alternating pressure air flotation mattress. 880... Personal Use Therapeutic Devices § 880.5550 Alternating pressure air flotation mattress. (a) Identification...

  17. 33 CFR 183.225 - Flotation test for persons capacity.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Flotation test for persons capacity. 183.225 Section 183.225 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Boats Rated for Engines of More Than 2 Horsepower Tests § 183.225 Flotation test for persons...

  18. 33 CFR 183.325 - Flotation test for persons capacity.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Flotation test for persons capacity. 183.325 Section 183.325 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND... Boats Rated for Engines of 2 Horsepower or Less Tests § 183.325 Flotation test for persons...

  19. Hybrid Modeling of Flotation Height in Air Flotation Oven Based on Selective Bagging Ensemble Method

    Directory of Open Access Journals (Sweden)

    Shuai Hou

    2013-01-01

    Full Text Available The accurate prediction of the flotation height is very necessary for the precise control of the air flotation oven process, therefore, avoiding the scratch and improving production quality. In this paper, a hybrid flotation height prediction model is developed. Firstly, a simplified mechanism model is introduced for capturing the main dynamic behavior of the process. Thereafter, for compensation of the modeling errors existing between actual system and mechanism model, an error compensation model which is established based on the proposed selective bagging ensemble method is proposed for boosting prediction accuracy. In the framework of the selective bagging ensemble method, negative correlation learning and genetic algorithm are imposed on bagging ensemble method for promoting cooperation property between based learners. As a result, a subset of base learners can be selected from the original bagging ensemble for composing a selective bagging ensemble which can outperform the original one in prediction accuracy with a compact ensemble size. Simulation results indicate that the proposed hybrid model has a better prediction performance in flotation height than other algorithms’ performance.

  20. Oil sands thickened froth treatment tailings exhibit acid rock drainage potential during evaporative drying.

    Science.gov (United States)

    Kuznetsov, Petr; Kuznetsova, Alsu; Foght, Julia M; Siddique, Tariq

    2015-02-01

    Bitumen extraction from oil sands ores after surface mining produces different tailings waste streams: 'froth treatment tailings' are enriched in pyrite relative to other streams. Tailings treatment can include addition of organic polymers to produce thickened tailings (TT). TT may be further de-watered by deposition into geotechnical cells for evaporative drying to increase shear strength prior to reclamation. To examine the acid rock drainage (ARD) potential of TT, we performed predictive analyses and laboratory experiments on material from field trials of two types of thickened froth treatment tailings (TT1 and TT2). Acid-base accounting (ABA) of initial samples showed that both TT1 and TT2 initially had net acid-producing potential, with ABA values of -141 and -230 t CaCO₃ equiv. 1000 t(-1) of TT, respectively. In long-term kinetic experiments, duplicate ~2-kg samples of TT were incubated in shallow trays and intermittently irrigated under air flow for 459 days to simulate evaporative field drying. Leachates collected from both TT samples initially had pH~6.8 that began decreasing after ~50 days (TT2) or ~250 days (TT1), stabilizing at pH~2. Correspondingly, the redox potential of leachates increased from 100-200 mV to 500-580 mV and electrical conductivity increased from 2-5 dS m(-1) to 26 dS m(-1), indicating dissolution of minerals during ARD. The rapid onset and prolonged ARD observed with TT2 is attributed to its greater pyrite (13.4%) and lower carbonate (1.4%) contents versus the slower onset of ARD in TT1 (initially 6.0% pyrite and 2.5% carbonates). 16S rRNA gene pyrosequencing analysis revealed rapid shift in microbial community when conditions became strongly acidic (pH~2) favoring the enrichment of Acidithiobacillus and Sulfobacillus bacteria in TT. This is the first report showing ARD potential of TT and the results have significant implications for effective management of pyrite-enriched oil sands tailings streams/deposits. Copyright © 2014

  1. A novel surfactant S-benzoyl-N,N-diethyldithiocarbamate synthesis and its flotation performance to galena

    Science.gov (United States)

    Ma, Xin; Hu, Yuan; Zhong, Hong; Wang, Shuai; Liu, Guangyi; Zhao, Gang

    2016-03-01

    In this paper, a novel dithiocarbamate compound, S-benzoyl-N,N-diethyldithiocarbamate (BEDTC), was synthesized via one-pot reaction of diethylamine, carbon disulfide, sodium hydroxide and benzoyl chloride using abundant carbon disulfide as a solvent. Its flotation performance and adsorption mechanism on the galena was first investigated by flotation tests, adsorption quantity measurements, FTIR spectra, X-ray photoelectron spectra (XPS) and density functional theory (DFT) calculation. The flotation results illustrated that BEDTC exhibited stronger collecting power than the conventional sulphide collectors such as sodium diethyl dithiocarbamate (SEDTC) and sodium isobutyl xanthate (SIBX) and superior selectivity for galena against sphalerite. The adsorption data demonstrated that the adsorption affinity of BEDTC to galena was stronger than that of SEDTC and SIBX, and the preferable pH range for BEDTC adsorption on galena surfaces was 6-10. The results of FTIR spectra and XPS indicated that the interaction of BEDTC with galena may be dominated by the chemical adsorption, which was further confirmed by DFT calculation. BEDTC probably acted as a bidentate ligand, bonding with lead through the thiol sulfur and carbonyl oxygen atoms to form two distinct adsorption geometries, one with the same Pb atom to form a six-membered ring complex, and the other with two different Pb atoms to form a "bullet" shape complex.

  2. Simulating a fuzzy level controller for flotation columns

    Institute of Scientific and Technical Information of China (English)

    Liao Yinfei; Liu Jiongtian; Wang Yongtian; Cao Yijun

    2011-01-01

    Level control in flotation columns is an important factor that influences the recovery and the grade of concentrate from the column.A flotation column is a nonlinear,multi-variable problem with changeable parameters that traditional methods have difficulty controlling.We have applied fuzzy control methods to the flotation column and tested the performance of the design by Matlab/Simulink simulation.The simulations show that level control in the flotation column becomes smoother and more rapid with the fuzzy controller.Compared to PID control methods the overshoot in valve position,the adjustment time,and the robustness of the controller are all improved.This indicates that it is suitable to model fuzzy controllers in applications for the study of automatic control of flotation column.

  3. Flotation studies on low grade graphite ore from eastern India

    Institute of Scientific and Technical Information of China (English)

    Vasumathi N.; Vijaya Kumar T.V.; Ratchambigai S.; Subba Rao S.; Bhaskar Raju G

    2015-01-01

    A low grade graphite ore from eastern India was beneficiated by flotation to improve its quality. The ore was composed of 87.80%ash and 8.59%fixed carbon. Primary coarse wet grinding (d80:186 lm) followed by rougher flotation in Denver flotation cell using diesel as collector and pine oil as frother yielded a rougher concentrate. Regrinding (d80:144 lm) of this rougher concentrate was opted for further libera-tion of graphite. It was followed by cleaning in laboratory flotation column. This combined process of relatively coarse primary grinding followed by regrinding and cleaning in flotation column resulted in final concentrate of 7.44% yield with 89.65% fixed carbon and 6.00% ash. This approach of two-stage grinding to recover the flake graphite at the coarsest possible grind can help to minimize grinding energy costs. A conceptual flow sheet which is cost effective was developed based on this methodology.

  4. Pressure flotation of nitrocellulose fines: Hydrodynamics and interfacial chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Grasso, D.; Hu, H.L. [Univ. of Connecticut, Storrs, CT (United States); LaFrance, P. [CH2M Hill, Denver, CO (United States); Kim, B.J. [Army Construction Engineering Lab., Champaign, IL (United States)

    1996-11-01

    The production of nitrocellulose (NC) creates large quantities of waste NC fines in wash water streams. Current processing techniques attempt to remove these fines by cross-flow microfiltration, pressure flotation, settling, centrifugation, and lime precipitation. Pressure flotation, or dissolved air flotation (DAF), is a solid/liquid separation process first developed in the ore processing industry. DAF has since found many applications in the environmental engineering field including: drinking water clarification, sludge thickening, and the clarification of wastewater from a variety of industrial and municipal processes. The work presented herein is part of a larger effort to explore techniques to recover and reuse nitrocellulose (NC) fines resulting from propellant manufacturing processes. Previous papers investigated NC particle stability and interfacial thermodynamics and developed a flotation trajectory model. This paper builds on that work and presents a sensitivity analysis of the flotation trajectory model. The sensitivity analysis explores both operational and parameter estimation uncertainty.

  5. A novel surfactant S-benzoyl-N,N-diethyldithiocarbamate synthesis and its flotation performance to galena

    Energy Technology Data Exchange (ETDEWEB)

    Ma, Xin; Hu, Yuan; Zhong, Hong, E-mail: zhongh@csu.edu.cn; Wang, Shuai, E-mail: wangshuai@csu.edu.cn; Liu, Guangyi; Zhao, Gang

    2016-03-01

    Graphical abstract: - Highlights: • A novel surfactant BEDTC was first introduced as galena flotation collector. • BEDTC exhibited superior collecting power to galena against sphalerite. • BEDTC has two active centers to mineral surfaces. • BEDTC molecules formed two distinct adsorption geometries on galena surfaces. - Abstract: In this paper, a novel dithiocarbamate compound, S-benzoyl-N,N-diethyldithiocarbamate (BEDTC), was synthesized via one-pot reaction of diethylamine, carbon disulfide, sodium hydroxide and benzoyl chloride using abundant carbon disulfide as a solvent. Its flotation performance and adsorption mechanism on the galena was first investigated by flotation tests, adsorption quantity measurements, FTIR spectra, X-ray photoelectron spectra (XPS) and density functional theory (DFT) calculation. The flotation results illustrated that BEDTC exhibited stronger collecting power than the conventional sulphide collectors such as sodium diethyl dithiocarbamate (SEDTC) and sodium isobutyl xanthate (SIBX) and superior selectivity for galena against sphalerite. The adsorption data demonstrated that the adsorption affinity of BEDTC to galena was stronger than that of SEDTC and SIBX, and the preferable pH range for BEDTC adsorption on galena surfaces was 6–10. The results of FTIR spectra and XPS indicated that the interaction of BEDTC with galena may be dominated by the chemical adsorption, which was further confirmed by DFT calculation. BEDTC probably acted as a bidentate ligand, bonding with lead through the thiol sulfur and carbonyl oxygen atoms to form two distinct adsorption geometries, one with the same Pb atom to form a six-membered ring complex, and the other with two different Pb atoms to form a ''bullet'' shape complex.

  6. Study on the accelerant to the sodium oleate during bauxite flotation

    Institute of Scientific and Technical Information of China (English)

    Liu Sanjun; Hu Yuehua; Qin Wenqing

    2012-01-01

    The conventional collector for diaspore mineral is oleic acid (OLA), which is highly insoluble and must be used in high dosage in bauxite flotation. Firstly flotation experiments with every reagent (sodium oleate, tween-20)were carried out and it was shown that sodium oleate was an effective diaspore collector, whereas nonionic surfactant tween-20 showed little collectivity. Then experiments were carried out with sodium oleate as the main collector with the addition of tween-20 to study the influences of potentiator on diaspore flotation. It could be seen from the experiments that potentiator had a marked influence on the recovery of diaspore, which was raised by more than 12 % and that addition sequence also affected the flotation behavior. It gave the best results with the reagents mixed thoroughly before added and the best ratio of collector oleic acid and potentiator tween-20 slLood at 10: 1. From the calculation of the ingredients in the sodium oleate solution, at the pH 9, sodium oleate acted with surface of the mineral with the acid-soap polymer [ HOL ~ OL- ]. Zeta potential test showed that the potentiator promoted the absorption of collector on the mineral surface, which lowered zeta potential. As could be seen from surface tension experiments, the addition of potentiator tween-20 lowered the CMC ( critical micelle concentration) value of oleic acid solution, which was equivalent to raise the power of the agents. By the adsorptive capability tests, with the addition of tween-20, the adsorption of oleic acid on diaspore got more.

  7. Kinetics and Hydrodynamics of Silver Ion Flotation

    OpenAIRE

    2012-01-01

    This paper studies and determines the dispersion properties (Jg, Eg and Db), kinetics parameters and hydrodynamics of the process and its effect on the recovery of silver contained in spent diluted fixers by techniques of ion flotation in columns. The experimental results show silver recoveries of 97 % using sodium isopropyl xanthate (SIX) 0.06 g·L-1 and 0.04 g·L-1 of frother, at a Jg of 1.0 cm·s-1 and Jl of 0.72 cm·s-1. Xanthate-promoter combinations do not improve the separation; however, r...

  8. The sensitivity of direct faecal examination, direct faecal flotation, modified centrifugal faecal flotation and centrifugal sedimentation/flotation in the diagnosis of canine spirocercosis

    Directory of Open Access Journals (Sweden)

    J. Christie

    2011-04-01

    Full Text Available Several faecal examination techniques have shown variable sensitivity in demonstrating Spirocerca lupi (S. lupi eggs. The objective of this study was to determine which faecal examination technique, including a novel modified centrifugal flotation technique, was most sensitive to diagnose spirocercosis. Ten coproscopic examinations were performed on faeces collected from 33 dogs confirmed endoscopically to have spirocercosis. The tests included a direct faecal examination, a faecal sedimentation/flotation test, 4 direct faecal flotations and 4 modified faecal centrifugal flotations. These latter 2 flotation tests utilised 4 different faecal flotation solutions:NaNO3 (SG 1.22,MgSO4 (SG 1.29,ZnSO4 (SG 1.30 and sugar (SG 1.27. The sensitivity of the tests ranged between 42 %and 67 %, with theNaNO3 solution showing the highest sensitivity in both the direct and modified-centrifugal flotations. The modified NaNO3 centrifugal method ranked 1st with the highest mean egg count (45.24±83, and was superior (i.e. higher egg count and significantly different (P< 0.05 compared with the routine saturated sugar,ZnSO4 andMgSO4 flotation methods. The routine NaNO3 flotation method was also superior and significantly different (P < 0.05 compared with the routine ZnSO4 andMgSO4 flotation methods. Fifteen per cent (n=5 of dogs had neoplastic oesophageal nodules and a further 18 % (n = 6 had both neoplastic and non-neoplastic nodules. S. lupi eggs were demonstrated in 40%of dogs with neoplastic nodules only and 72.9 % of the dogs with non-neoplastic nodules. The mean egg count in the non-neoplastic group (61 was statistically greater (P = 0.02 than that of the neoplastic group (1. The results show that faecal examination using a NaNO3 solution is the most sensitive in the diagnosis of spirocercosis. The modified centrifugal flotation faecal method using this solution has the highest egg count. The study also found that dogs with neoplastic nodules shed

  9. The sensitivity of direct faecal examination, direct faecal flotation, modified centrifugal faecal flotation and centrifugal sedimentation/flotation in the diagnosis of canine spirocercosis.

    Science.gov (United States)

    Christie, J; Schwan, E V; Bodenstein, L L; Sommerville, J E M; van der Merwe, L L

    2011-06-01

    Several faecal examination techniques have shown variable sensitivity in demonstrating Spirocerca lupi (S. lupi) eggs. The objective of this study was to determine which faecal examination technique, including a novel modified centrifugal flotation technique, was most sensitive to diagnose spirocercosis. Ten coproscopic examinations were performed on faeces collected from 33 dogs confirmed endoscopically to have spirocercosis. The tests included a direct faecal examination, a faecal sedimentation/flotation test, 4 direct faecal flotations and 4 modified faecal centrifugal flotations. These latter 2 flotation tests utilised 4 different faecal flotation solutions: NaNO3 (SG 1.22), MgSO4 (SG 1.29), ZnSO4 (SG 1.30) and sugar (SG 1.27). The sensitivity of the tests ranged between 42% and 67%, with the NaNO3 solution showing the highest sensitivity in both the direct and modified-centrifugal flotations. The modified NaNO3 centrifugal method ranked 1st with the highest mean egg count (45.24 +/- 83), and was superior (i.e. higher egg count) and significantly different (P < 0.05) compared with the routine saturated sugar, ZnSO4 and MgSO4 flotation methods. The routine NaNO3 flotation method was also superior and significantly different (P < 0.05) compared with the routine ZnSO4 and MgSO4 flotation methods. Fifteen per cent (n = 5) of dogs had neoplastic oesophageal nodules and a further 18% (n = 6) had both neoplastic and non-neoplastic nodules. S. lupi eggs were demonstrated in 40% of dogs with neoplastic nodules only and 72.9% of the dogs with non-neoplastic nodules. The mean egg count in the non-neoplastic group (61) was statistically greater (P = 0.02) than that of the neoplastic group (1). The results show that faecal examination using a NaNO3 solution is the most sensitive in the diagnosis of spirocercosis. The modified centrifugal flotation faecal method using this solution has the highest egg count. The study also found that dogs with neoplastic nodules shed

  10. 脉冲磁场在旋流-静态微泡浮选柱中的应用%Application of the Pulsed Magnetic Field in the Cyclone-static Microbubble Flotation Column

    Institute of Scientific and Technical Information of China (English)

    李超; 曹亦俊; 杨兴满; 牛国鹏; 刘永华

    2011-01-01

    为降低某磁铁矿选矿厂的浮选尾矿品位,进行了新型磁浮选脱硅试验研究.结果表明,相比常规旋流-静态微泡浮选柱1次粗选、2次扫选反浮选工艺流程,浮选柱柱体附加脉冲磁场后采用1次粗选、1次扫选工艺流程,在入浮原矿性质和精矿品位基本相同的情况下,浮选时间缩短了30%,尾矿品位降低了6.35个百分点,回收率提高0.95个百分点.磁浮选方法在磁铁矿反浮选中的应用,为我国磁铁矿分选开辟一条新的途径.%In order to reduce the flotation tailings grade of a dressing plant of magnetite, experimental researches on the new magnetic flotation with silicon removal were carried out. The results showed that comparing with the conventional inverse flotation process of one-roughing and two-scavenging with cyclone-static microbubble flotation column, the process of one-roughing and one-scavenging after the flotation column was added with an additional pulsed magnetic field shortened the flotation time of 30%, reduced the tailings grade by 6.35 percent, and increased the recovery by 0.95 percent under the similar circumstances of raw ore' s nature and concentrate grade before the flotation. The application of magnetic flotation method in reverse flotation of magnetite opens up a new approach for the separation of magnetite in China.

  11. Heavy metal removal from waste waters by ion flotation.

    Science.gov (United States)

    Polat, H; Erdogan, D

    2007-09-05

    Flotation studies were carried out to investigate the removal of heavy metals such as copper (II), zinc (II), chromium (III) and silver (I) from waste waters. Various parameters such as pH, collector and frother concentrations and airflow rate were tested to determine the optimum flotation conditions. Sodium dodecyl sulfate and hexadecyltrimethyl ammonium bromide were used as collectors. Ethanol and methyl isobutyl carbinol (MIBC) were used as frothers. Metal removal reached about 74% under optimum conditions at low pH. At basic pH it became as high as 90%, probably due to the contribution from the flotation of metal precipitates.

  12. Aspiration spiral-flow type centrifugal flotation machine

    Institute of Scientific and Technical Information of China (English)

    陈文义

    2002-01-01

    Aspiration spiral flow type centrifugal flotation machine takes full advantage of centrifugal force field and gravitational field, and strengthens flotation of coal slurry. As a new-type flotation machine of high efficiency, its key component is bubble generator. Which completes the process of ore pulp inflation and liberalization. The design, parameters and working principle of bubble generator provide the design of the same device in similar equipment with reference. The result of industrial operation shows that this machine is of such features as small occupational area, greater concentration ratio, high processing capacity, high efficiency and lower investment etc.

  13. Trace metal mobilization from oil sands froth treatment thickened tailings exhibiting acid rock drainage.

    Science.gov (United States)

    Kuznetsova, Alsu; Kuznetsov, Petr; Foght, Julia M; Siddique, Tariq

    2016-11-15

    Froth treatment thickened tailings (TT) are a waste product of bitumen extraction from surface-mined oil sands ores. When incubated in a laboratory under simulated moist oxic environmental conditions for ~450d, two different types of TT (TT1 and TT2) exhibited the potential to generate acid rock drainage (ARD) by producing acid leachate after 250 and 50d, respectively. We report here the release of toxic metals from TT via ARD, which could pose an environmental threat if oil sands TT deposits are not properly managed. Trace metal concentrations in leachate samples collected periodically revealed that Mn and Sr were released immediately even before the onset of ARD. Spikes in Co and Ni concentrations were observed both pre-ARD and during active ARD, particularly in TT1. For most elements measured (Fe, Cr, V, As, Cu, Pb, Zn, Cd, and Se), leaching was associated with ARD production. Though equivalent acidification (pH2) was achieved in leachate from both TT types, greater metal release was observed from TT2 where concentrations reached 10,000ppb for Ni, 5000ppb for Co, 3000ppb for As, 2000ppb for V, and 1000ppb for Cr. Generally, metal concentrations decreased in leachate with time during ARD and became negligible by the end of incubation (~450d) despite appreciable metals remaining in the leached TT. These results suggest that using TT for land reclamation purposes or surface deposition for volume reduction may unfavorably impact the environment, and warrants application of appropriate strategies for management of pyrite-enriched oil sands tailings streams.

  14. A novel capillary electrophoresis method with pressure assisted field amplified sample injection in determination of thiol collectors in flotation process waters.

    Science.gov (United States)

    Sihvonen, T; Aaltonen, A; Leppinen, J; Hiltunen, S; Sirén, H

    2014-01-17

    A new capillary electrophoresis method was developed for the quantification of diisobutyldithiophosphate (DTP), diisobutyldithiophosphinate (DTPI) and ethyl and isobutyl xanthates (EX, IBX) all of which are used as thiol collectors in froth flotation. This method uses pressure assisted field amplified sample injection (PA-FASI) to concentrate the analytes at the capillary inlet. The background electrolyte in electrophoretic separation was 60millimolar (mM) from 3-(cyclohexylamino)propane-1-sulfonic acid (CAPS) in 40mM NaOH solution. The similar CAPS electrolyte solution has earlier been used for screening for diuretics that contained sulphonamide and/or carboxylic groups. In this study, the functional groups are xanthate, phosphate and phosphinate. The method was developed using actual flotation process waters. The results showed that the water delivered from the plant did not contain significant amount of collectors; therefore, method development was accomplished by spiking analytes in these waters. Separation of analytes was achieved in 15min. The range of quantification was 0.27-66.6mg/L (R(2) 0.9991-0.9999) for all analytes other than ethyl xanthate, for which the range was 0.09-66.6mg/L (R(2) 0.9999). LOD (S/N=3) and LOQ (S/N=10) values for DTP, DTPI, IBX and EX were 0.05, 0.07, 0.06 and 0.01mg/L and 0.16, 0.25, 0.21 and 0.04mg/L, respectively. No interference from the matrices was observed, when the method was tested at a gold concentrator plant.

  15. Basic Conditions Research for Recovering Silver from Zinc Leaching Residues by Flotation%从锌浸出渣中浮选银基础条件研究

    Institute of Scientific and Technical Information of China (English)

    郭天立; 崔志刚; 李国伟; 贾乙东; 王克

    2013-01-01

    This paper researches the flotation characters of acidic leaching residues in conventional zinc leac-hing process in zinc hydrometallurgy , then it discusses and provides the main conditions for recovering sil-ver from conventional zinc leaching residues by flotation . It considers that this process has the obvious ad-vantage , w hich uses acidic conventional zinc leaching residues as the original pulp to recover silver by flota-tion . By this flotation process , higher silver recovery rate , greater production rate and higher concentrate grade can be arrived , and the gold can be enriched to recover at the same time .%研究了湿法炼锌常规浸出工艺下酸性浸出渣的浮选性质,提出并讨论了从锌常规浸出渣中浮选回收银的关键条件,认为锌常规浸出的酸浸矿浆直接作为原矿浆用于浮选回收银的工艺路线优势明显,银浮选回收可以达到较好的回收率、产率和精矿品位指标,并能在浮选中同时有效富集回收金。

  16. ENVIRONMENTAL ISSUE IN COPPER ORE FLOTATION BY XANTHATES

    National Research Council Canada - National Science Library

    Zoran Markovic

    2015-01-01

      This paper presents some investigation results about potassium ethyl xanthate (PEX) stability in water solution at higher pH and in presence of mineral chalcopyrite, related to flotation of copper minerals from copper ore...

  17. Application of Hydrodynamics in Design of Flotation Deinking Cell

    Science.gov (United States)

    Li, R. G.; Xie, X. F.; Wang, A. L.; Chen, K. F.

    Recovery and recycling of waste paper has become increasingly important with demand for paper products sharply growing. The flotation process is the predominant technology for the removal of inks from waste paper because of its advantages. Flotation cells may be very different in size and shape, but the key elements ensuring aeration, ink collection and bubble separation are always present. Different aeration systems have been developed by the equipment suppliers. The hydrodynamic method, based on the self suction and mixing of air according to the Venturi principle has become the most common aeration technique. Injectors of various sizes and designs have been investigated and constantly improved and adapted to different designs of flotation units. Step diffuser is a common and predominant injector used in the flotation deinking cell.

  18. Effect and mechanism of siderite on reverse flotation of hematite

    Institute of Scientific and Technical Information of China (English)

    Wan-zhong Yin; Dong Li; Xi-mei Luo; Jin Yao; Qian-yu Sun

    2016-01-01

    The effects of siderite on reverse flotation of hematite were investigated using micro flotation, adsorption tests, and Fourier trans-form infrared spectroscopy. The flotation results show that interactions between siderite and quartz are the main reasons that siderite signifi-cantly influences the floatability. The interactions are attributed to dissolved siderite species and fine siderite particles. The interaction due to the dissolved species is, however, dominant. Derjaguin-Landau-Verwey-Overbeek (DLVO) theoretical calculations reveal that adhesion on quartz increases when the siderite particle size decreases and that fine particles partly influence quartz floatability. Chemical solution calcula-tions indicate that the dissolved species of siderite might convert the surface of active quartz to CaCO3 precipitates that can be depressed by starch. The theoretical calculations are in good agreement with the results of adsorption tests and FTIR spectroscopy and explain the reasons why siderite significantly influences reverse flotation of hematite.

  19. Effect of temperature on coal flotation performance - A review

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharya, S.; Pascoe, R.D. [Indian School of Mines, Dhanbad (India). Dept. of Fuel & Mineral Engineering

    2005-03-01

    Though substantial coal-washing activities are carried out in a tropical climate, in the 70-yr history of coal flotation, the effect of diurnal and seasonal variations in temperature as an operational variable has received only limited attention. This review examines the current knowledge on the effect of temperature on coal flotation performance and finds that coals with strong natural hydrophobicity do not seem to be affected by a variation in pulp temperature. Difficult-to-float coals, however, appear to float well within a temperature range of 20 - 35{degree}C with considerable improvement in all flotation indices, concentrate yield and ash, recovery of combustibles, flotation rate, and tailing ash as compared to their values at higher or lower temperature.

  20. Raman spectroscopic study of some chalcopyrite-xanthate flotation products

    CSIR Research Space (South Africa)

    Andreev, GN

    2003-12-16

    Full Text Available The ability of Raman spectroscopy to investigate chemical substances in water media was applied for studying the surface products of the chalcopyrite-sodium isopropyl xanthate flotation system. Performing the reaction in model conditions, i...

  1. Effect of hydroxamic acid polymers on reverse flotation of bauxite

    Institute of Scientific and Technical Information of China (English)

    李海普; 胡岳华; 王淀佐; 徐兢

    2004-01-01

    The effect of hydroxamic acid starch (HAS) and hydroxamic acid polyacrylamide (HPAM) on the flotation of diaspore and kaolinite was investigated by flotation test. It is found that HAS depresses diaspore but activates kaolinite in acidic pulp,while HPAM activates both diaspore and kaolinite in the pH range of 2.0 - 10.5. The measurement of zeta potential shows that both HAS and HPAM can increase zeta potential of negatively charged diaspore, which indicates the existence of chemical bonding or hydrogen bonding between the reagents and diaspore.By covering the collector dodecyl amine(DDA) on diaspore surface, HAS increases the hydrophilicity of minerals and depresses the flotation of diaspore,however HPAM activates the flotation of diaspore by increasing the adsorption of DDA on diaspore surface.

  2. A comparison study of commercially-available column flotation technologies

    Energy Technology Data Exchange (ETDEWEB)

    Honaker, R.Q.; Mohanty, M.K.; Paul, B.C. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Mining Engineering; Ho, K. [Illinois Clean Coal Inst., Carterville, IL (United States)

    1994-12-31

    A direct comparison of three commercially-available column flotation technologies, i.e., Jameson Cell, Microcel, and Packed-Column, has been conducted using a {minus}100 mesh Illinois No. 5 flotation feed coal sample. The separation performance of each flotation technology was optimized and their performance levels compared on the basis of both ash rejection, sulfur rejection, and throughput capacities. A parametric study using a statistically-designed experimental program was conducted to optimize the critical operating parameter values of each column. The ultimate performance curves for each column were generated by conducting additional tests using the optimized operating parameter values. The throughput capacity of each flotation cell was determined by conducting tests over a range of feed rates at the maximum superficial gas rate while maintaining the other parameters at their optimum values. The separation performance achieved by each of the three flotation cells was found to be comparable to the idealistic flotation performance predicted by release analysis. However, the fraction of wash water reporting to tailings (bias factor) was found to be critical in achieving the near idealistic performance. The bias factor required for the Packed-Column was found to be less than that required by the other two flotation cells. The sulfur rejection achieved by the Microcel and the Packed-Column were found to be greater than that achieved by the Jameson Cell and all three produced sulfur rejections exceeding the values obtained from release analysis. The throughput capacity, on the other hand, differed among the three flotation columns. The Jameson Cell and the Microcel were found to have comparable throughput capacities while the Packed-Column was found to have a lower capacity.

  3. Complex mineral recovery from the copper flotation tailing

    OpenAIRE

    Krstev, Boris; Golomeov, Blagoj

    2005-01-01

    The generally concept of the carried out investigations is discovering an appropriate technological scheme of the possible complex mineral utilisation from the copper flotation tailing. The Bucim - mine laboratory investigations of the flotation tailing are based on the demands of the possible complex recovery from the useful present minerals or mineral components: CuFeS2; FeS2; Fe2O3; Fe3O4; Na-feldspar and K-feldspar; SiO2 etc.

  4. Boiling treatment of ABS and PS plastics for flotation separation.

    Science.gov (United States)

    Wang, Chong-qing; Wang, Hui; Wu, Bao-xin; Liu, Qun

    2014-07-01

    A new physical method, namely boiling treatment, was developed to aid flotation separation of acrylonitrile-butadiene-styrene (ABS) and polystyrene (PS) plastics. Boiling treatment was shown to be effective in producing a hydrophilic surface on ABS plastic. Fourier Transform Infrared analysis was conducted to investigate the mechanism of boiling treatment of ABS. Surface rearrangement of polymer may be responsible for surface change of boiling treated ABS, and the selective influence of boiling treatment on the floatability of boiling treated plastics may be attributed to the difference in the molecular mobility of polymer chains. The effects of flotation time, frother concentration and particle size on flotation behavior of simple plastic were investigated. Based on flotation behavior of simple plastic, flotation separation of boiling treatment ABS and PS with different particle sizes was achieved efficiently. The purity of ABS and PS was up to 99.78% and 95.80%, respectively; the recovery of ABS and PS was up to 95.81% and 99.82%, respectively. Boiling treatment promotes the industrial application of plastics flotation and facilitates plastic recycling.

  5. Modelling Of Flotation Processes By Classical Mathematical Methods - A Review

    Science.gov (United States)

    Jovanović, Ivana; Miljanović, Igor

    2015-12-01

    Flotation process modelling is not a simple task, mostly because of the process complexity, i.e. the presence of a large number of variables that (to a lesser or a greater extent) affect the final outcome of the mineral particles separation based on the differences in their surface properties. The attempts toward the development of the quantitative predictive model that would fully describe the operation of an industrial flotation plant started in the middle of past century and it lasts to this day. This paper gives a review of published research activities directed toward the development of flotation models based on the classical mathematical rules. The description and systematization of classical flotation models were performed according to the available references, with emphasize exclusively given to the flotation process modelling, regardless of the model application in a certain control system. In accordance with the contemporary considerations, models were classified as the empirical, probabilistic, kinetic and population balance types. Each model type is presented through the aspects of flotation modelling at the macro and micro process levels.

  6. Interfacial interactions between plastic particles in plastics flotation.

    Science.gov (United States)

    Wang, Chong-qing; Wang, Hui; Gu, Guo-hua; Fu, Jian-gang; Lin, Qing-quan; Liu, You-nian

    2015-12-01

    Plastics flotation used for recycling of plastic wastes receives increasing attention for its industrial application. In order to study the mechanism of plastics flotation, the interfacial interactions between plastic particles in flotation system were investigated through calculation of Lifshitz-van der Waals (LW) function, Lewis acid-base (AB) Gibbs function, and the extended Derjaguin-Landau-Verwey-Overbeek potential energy profiles. The results showed that van der Waals force between plastic particles is attraction force in flotation system. The large hydrophobic attraction, caused by the AB Gibbs function, is the dominant interparticle force. Wetting agents present significant effects on the interfacial interactions between plastic particles. It is found that adsorption of wetting agents promotes dispersion of plastic particles and decreases the floatability. Pneumatic flotation may improve the recovery and purity of separated plastics through selective adsorption of wetting agents on plastic surface. The relationships between hydrophobic attraction and surface properties were also examined. It is revealed that there exists a three-order polynomial relationship between the AB Gibbs function and Lewis base component. Our finding provides some insights into mechanism of plastics flotation.

  7. Effect of Flotation Time on the Deinking Process and Properties of Deinked Pulp

    Directory of Open Access Journals (Sweden)

    Sami İmamoğlu

    2012-11-01

    Full Text Available This paper discusses the influence of flotation time on the ink removal and physical properties of resulting deinked pulp. Flotation deinking of high quality office paper, printed in a digital duplicating machine based on screen-printing system, was studied using a laboratory cell with a nominal capacity of 10 L. Formamidine sulfinic acid was used in a pulper and pulping conditions such as temperature, retention time, chemical dosage and consistency were held constant prior to flotation process. During the flotation process while pulp consistency, agitation speed, air flow rate and other conditions keeping constant, only flotation time were analyzed in terms of physical properties of resulting pulp quality, pulp yield, filler and fibre balance and waste water quality aspects at 0, 3, 6, 9, 12 and 15 minutes. Increased flotation time substantially affected optical properties of pulp up to some point then became steady. Yield losses increased as might be expected with increasing flotation time by the 9th minute as flotation sludge skimmed off on top of the flotation cell. Filler content of flotation sludge increased with increasing flotation time while fibre content was decreasing to a certain extent. Thanks to removal of ink and filler materials from pulp physical properties of evaluated handsheets enhanced. The overall results demonstrate that increasing flotation time increased physical and optical properties of resulting pulp. On the other hand flotation time should be increased up to critical point. Exceeding critical point increased yield losses, consumed time and energy without gaining significant pulp qualities.

  8. Flotation of kaolinite with dodecyl tertiary amines

    Institute of Scientific and Technical Information of China (English)

    CAO Xue-feng; LIU Chang-miao; HU Yue-hua

    2009-01-01

    The flotation of kaolinite using a series of tertiary amines (N,N-dimethyl-dodecyl amine (DRN), N,N-diethyl-dodecyl amine (DEN), N,N-dipropyl-dodecyl amine (DPN) and N,N-dibenzyl-bodecyi amine (DBN)) was investigated. The results show that the maximum recoveries of kaolinite for DEN, DPN and DRN are 93%, 88% and 84%, respectively, but that of DBN is very low. On the basis of zeta potential and FT-IR spectra, the ionization of surface hydroxyl and isomorphic exchange of surface ions account for the charging mechanisms of kaolinite surface. The adsorption mechanism of tertiary amines on kaolinite surface is mainly electrostatic. The isoelectric point (IEP) of kaolinite increases from 3.4 to some more positive points after the interaction of kaolinite with the four tertiary amines. The FT-IR spectra of kaolinite change with the presence of some new sharp shapes belonging to the tertiary amines. The inductive electronic effects and space-steric effects of -CH_3, -C_2H_5, -C_3H_7 and -C_7H_7 bonding to N atom result in different collecting power of the four tertiary amines.

  9. pH control in flotation process based on prediction model%基于预测模型的浮选过程pH值控制

    Institute of Scientific and Technical Information of China (English)

    唐朝晖; 刘金平; 陈青; 桂卫华; 杜金芳

    2013-01-01

    矿浆pH值是泡沫浮选过程中的一个非常重要的被控量.目前,多数选厂的矿浆pH值控制基本是依靠现场工人定期对矿浆样本进行pH值测量,凭主观经验对pH调整剂进行调整.由于操作工人的主观性和随意性的影响以及矿浆样本pH值测量与药剂调整间存在的较长的时间滞后,矿浆pH值波动频繁,很难使矿物浮选保持在一个稳定最优生产状态下运行.为了使矿浆pH值保持在一个期望的生产状态,基于浮选泡沫表面视觉信息提出了一种新的矿浆pH值控制方法,分别采用基于泡沫视觉信息的自适应遗传混合神经网络AG-HNN和自适应遗传PID(AG-PID)控制方法建立了矿浆pH值预测模型和pH值控制模型,基于所建立预测和控制模型对浮选药剂用量进行调整,解决了浮选矿浆pH值波动问题.工业浮选现场的实验结果表明该方法可以使矿浆pH值保持在一个期望的范围内,有效提高浮选性能.%The pulp pH value is an important controlled variable for process operation in mineral flotation process,which is controlled through regularly adjusting reagent dosage by experienced workers according to the pH measurement results of the current pulp samples.However,due to the influence of the subjectivity and casualness of workers and the long time-lag between the pH measurement of the pulp sample and the reagent adjustment,the pH value of the pulp fluctuates frequently,causing unstable and undesirable production states for mineral flotation.A novel pH control method is proposed to maintain the pulp pH value at an expected production state based on the froth visual information.Firstly,a pH prediction model and a pH control model are built by froth visual information based on the adaptive genetic hybrid neural network (AG-HNN) and adaptive genetic PID (AG-PID) control method,respectively; and then the dosage is adjusted according to the pH value prediction model and the pH control model

  10. Leaching characteristics of copper flotation waste before and after vitrification.

    Science.gov (United States)

    Coruh, Semra; Ergun, Osman Nuri

    2006-12-01

    Copper flotation waste from copper production using a pyrometallurgical process contains toxic metals such as Cu, Zn, Co and Pb. Because of the presence of trace amounts of these highly toxic metals, copper flotation waste contributes to environmental pollution. In this study, the leaching characteristics of copper flotation waste from the Black Sea Copper Works in Samsun, Turkey have been investigated before and after vitrification. Samples obtained from the factory were subjected to toxicity tests such as the extraction procedure toxicity test (EP Tox), the toxicity characteristic leaching procedure (TCLP) and the "method A" extraction procedure of the American Society of Testing and Materials. The leaching tests showed that the content of some elements in the waste before vitrification exceed the regulatory limits and cannot be disposed of in the present form. Therefore, a stabilization or inertization treatment is necessary prior to disposal. Vitrification was found to stabilize heavy metals in the copper flotation waste successfully and leaching of these metals was largely reduced. Therefore, vitrification can be an acceptable method for disposal of copper flotation waste.

  11. Selective Flotation of Calcite from Fluorite: A Novel Reagent Schedule

    Directory of Open Access Journals (Sweden)

    Zhiyong Gao

    2016-10-01

    Full Text Available Fluorite is an important strategic mineral. In general, fluorite ores will contain a certain amount of calcite gangue mineral. Thus, they need to be separated from each other. For an economic separation, a reverse flotation process is used to float calcite gangue from fluorite. However, little information on the separation is available. In this study, a novel reagent schedule using citric acid (CA as the depressant, sodium fluoride (NaF as the regulator and sulfoleic acid (SOA as the collector, was developed to separate calcite from fluorite. The results demonstrated a high selectivity for the flotation of calcite from fluorite using this new reagent schedule. The best selective separation for a single mineral and mixed binary minerals was obtained when 200 mg/L of NaF, 50 mg/L of CA, and 6 mg/L of SOA were used at pH 9. In addition, a batch flotation experiment was carried out using a run-of-mine feed material. Selective separation was achieved with 85.18% calcite removal while only 11.2% of fluorite was lost. An attempt was made to understand the effect of the new reagent schedule on the flotation of calcite. The results from both microflotation and bench scale flotation demonstrated a great potential for industrial application using this novel reagent schedule to upgrade fluorite ore.

  12. Interaction of reactive oily bubble in flotation of bastnaesite

    Institute of Scientific and Technical Information of China (English)

    周芳; 王娄翔; 徐政和; 刘青侠; 池汝安

    2014-01-01

    To understand the flotation mechanism of bastnaesite using reactive oily bubble, the interaction between bastnaesite parti-cles and reactive oily bubbles was investigated by electro-kinetic studies, induction time measurements and small-scale flotation ex-periments. The bastnaesite flotation could be seen as a hetero-coagulation between bastnaesite particles and reactive oily bubbles which was confirmed by the zeta potential distribution and induction time measurements from pH 4.8 to pH 9.0. The small-scale flo-tation tests were consistent with the hetero-coagulation results, and showed a better flotation of reactive oily bubble than air bubble among all pH range. The interaction force between bastnaesite particles and reactive oily bubbles was evaluated by the classical DLVO theory. It indicated that the attachment could be predicted well by the DLVO theory only in a restricted pH range due to the absence of hydrophilic interaction repulsion force and chemical interaction force.

  13. 46 CFR 169.741 - Personal flotation devices and ring life buoys.

    Science.gov (United States)

    2010-10-01

    ... SCHOOL VESSELS Vessel Control, Miscellaneous Systems, and Equipment Markings § 169.741 Personal flotation devices and ring life buoys. Each personal flotation device and ring life buoy must be marked with the... 46 Shipping 7 2010-10-01 2010-10-01 false Personal flotation devices and ring life buoys....

  14. Intensification of the Reverse Cationic Flotation of Hematite Ores with Optimization of Process and Hydrodynamic Parameters of Flotation Cell

    Science.gov (United States)

    Poperechnikova, O. Yu; Filippov, L. O.; Shumskaya, E. N.; Filippova, I. V.

    2017-07-01

    The demand of high grade iron ore concentrates is a major issue due to the depletion of rich iron-bearing ores and high competitiveness in the iron ore market. Iron ore production is forced out to upgrade flowsheets to decrease the silica content in the pelettes. Different types of ore have different mineral composition and texture-structural features which require different mineral processing methods and technologies. The paper presents a comparative study of the cationic and anionic flotation routes to process a fine-grain oxidized iron ore. The modified carboxymethyl cellulose was found as the most efficient depressant in reverse cationic flotation. The results of flotation optimization of hematite ores using matrix of second-order center rotatable uniform design allowed to define the collector concentration, impeller rotation speed and air flowrate as the main flotation parameters impacting on the iron ore concentrate quality and iron recovery in a laboratory flotation machine. These parameters have been selected as independent during the experiments.

  15. Evaluation of column flotation results with a film flotation method; Film fusenho wo mochiita column fusen kekkan no hyoka

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, H.; Matsukata, M.; Ueyama, K. [Osaka University, Osaka (Japan). Faculty of Engineering Science

    1996-10-28

    Change in wettability of coal particle surfaces due to kerosene adsorption was studied by using a film flotation method. The applicability of a film flotation method to coals modified by kerosene adsorption was first confirmed. In experiment, film flotation was applied to Illinois coal modified by aqueous methanol solution and kerosene adsorption, and the weight percent of residual particles on a gas-liquid interface and kerosene in aqueous methanol solution were analyzed to verify the applicability of a film flotation method. Film flotation was applied to Datong and Illinois coals modified by kerosene adsorption, and the weight percent of residual particles on a gas-liquid interface was plotted to surface tension of liquid. As a result, the weight percent of hydrophobic particles within 50mN/m in surface tension slightly increased in Datong coal and remarkably increased in Illinois coal with kerosene addition. It was thus suggested that in addition to surface tension, the distributions of hydrophilic and hydrophobic strengths on the surface of each coal particle should be considered to understand attachment of coal particles and bubbles. 6 refs., 4 figs.

  16. Selective Sulfidation of Lead Smelter Slag with Pyrite and Flotation Behavior of Synthetic ZnS

    Science.gov (United States)

    Han, Junwei; Liu, Wei; Wang, Dawei; Jiao, Fen; Zhang, Tianfu; Qin, Wenqing

    2016-08-01

    The selective sulfidation of lead smelter slag with pyrite in the presence of carbon and Na salts, and the flotation behavior of synthetic ZnS were studied. The effects of temperature, time, pyrite dosage, Na salts, and carbon additions were investigated based on thermodynamic calculation, and correspondingly, the growth mechanism of ZnS particles was studied at high temperatures. The results indicated that the zinc in lead smelter slag was selectively converted into zinc sulfides by sulfidation roasting. The sulfidation degree of zinc was increased until the temperature, time, pyrite, and carbon dosages reached their optimum values, under which it was more than 95 pct. The growth of ZnS particles largely depended upon roasting temperature, and the ZnS grains were significantly increased above 1373 K (1100 °C) due to the formation of a liquid phase. After the roasting, the zinc sulfides generated had a good floatability, and 88.34 pct of zinc was recovered by conventional flotation.

  17. Application of IMHOFLOT G-cell centrifugal flotation technology

    Energy Technology Data Exchange (ETDEWEB)

    Imhof, R.; Fletcher, M.; Vathavooran, A.; Singh, A. [Maelgwyn Mining Services Ltd., Cardiff (United Kingdom)

    2007-10-15

    The Imhoflot G-Cell, a new development in the pneumatic flotation technology (which incorporates centrifugal forces in the separating vessel), is a recent innovation in the mineral processing world. The G-Cell was invented by Dr Rainer Imhof and commercialized by Maelgwyn Mineral Services Ltd. In a short time span a number of plants and units have been successfully commissioned in the mineral processing industry. In addition, a number of industrial G-Cell flotation plants are in the process of construction for the purpose of coal preparation and environmental remediation. In this paper two industrial installations have been highlighted, together with a pilot plant test programme investigating ultra-fine flotation recovery for a base metal operation.

  18. Treatment of milk industry effluent by dissolved air flotation

    Directory of Open Access Journals (Sweden)

    H. J .B. Couto

    2004-01-01

    Full Text Available In this work, the application of the flotation technique by dissolved air (FAD to the treatment of milk industry effluent (milky effluent is analyzed. Initially, batch studies were carried out in a column built of acrylic with an external diameter of 2.5 cm and 50 cm in height. Afterwards, the performance of a flotation tank with a 5.5 L capacity in the treatment of the milky effluent was addressed. In continuous mode of operation, separation efficiencies up to 90% were obtained for the experiments carried out at a saturation pressure of 4 atm and having a ratio of feed flow rate (Qa to saturated liquid flow rate equal to 1. The separation efficiency for flocculated milk was estimated from the overall mass balance for the flotation tank. Separation efficiencies obtained agreed very well with the experimental results collected for Qa/Q Ls ratios lower than 1.

  19. Influence of Emulsification of Composite Collector on Rutile Flotation

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The emulsifiable conditions of composite collector (FP-2) in industry are systematically researched in the paper. It is found that tpyes of the emulsifiers, emulsification temperature, the mixed proportion of FP-2 to emulsifier are the important parameters affecting emulsification effect and rutile flotation targets. When the proportion of FP-2 to emulsifier (E-4) is 100, by means of emulsification of mechanical stirring, the rutile flotation recovery is 85.6% and the grade is 75.3%, which approach the flotation targets of FP-2 used as collector by ultrasonic emulsification unit. The favorable conditions are set up for FP-2 in industry application. By means of XPS measurement,the chemical interaction of composite collector with rutile is found.

  20. Intensification of flotation treatment by exposure to vibration.

    Science.gov (United States)

    Ivanov, M V; Ksenofontov, B S

    2014-01-01

    In this paper, an intensification of wastewater flotation treatment by exposure to vibration is studied. Exposure to vibration results in the decrease of air bubble size, increase of air flow through the aerator and more even dispersion of air bubbles in water. This intensifies the aeration process, thus significantly improving the treatment efficiency. A multistage model of flotation kinetics has been applied in order to take into consideration the effects of vibration. The model gives a thorough explanation of the flotation process with consideration of 'air bubble - contaminant particle' aggregate formation. A large series of experiments was conducted with paint and varnish industry wastewaters. It is shown that vibroflotation results in an increase of treatment efficiency by up to three times. A comparison of the experimental data with the results of mathematical modeling is presented, showing a good correlation of theoretical and experimental results.

  1. Removal of arsenic in flotation of galena and sphalerite

    Science.gov (United States)

    Yu, Dae-hwan; Kim, Min-kyu; Han, Oh-hyung; Park, Chul-hyun

    2017-04-01

    In Korea, Janggun mine that produces the concentrate of galena (PbS) /sphalerite (ZnS) containing arsenic of 1.3% charges a penalty of US 3/ton to LS-Nikko smelter. Hence in this work, flotation tests for removal of arsenopyrite (FeAsS) from sulfide minerals were carried out using lab scale flotation cell, which maintain grade and recovery of PbS and ZnS in comparison to flotation plant. Particularly, this study was focused on investigating the combination of several chemical reagents such as depressant, collector, activator and etc. that affect flotation performance. In the straight differential flotation for PbS, a PbS grade of 67.80% and a recovery of 80.2% could be obtained with FeAsS removal of 84.1% (0.2% As) under the conditions of 20% feed solids concentration, pH 8.5, 50g/t frother (AF65), 50g/t collector (AP242) and 600g/t As depressant (NaHSO3) and 600g/t Zn depressant (ZnSO4). In the ZnS flotation, the maximum separation achievable for ZnS has been shown to be a grade of 50.27% and a recovery of 88.7%. At this time, FeAsS removal of 87.8% (0.16% As) could be successfully accomplished under pH 11, and 1.2kg/t Zn activator (CuSO4), 100g/t frother (AF65), 100g/t collector (AP211) and 400g/t As depressant (NaHSO3). Acknowledgments This work was supported by the Energy and Resources Engineering Program Grant funded by the Ministry of Trade, Industry and Energy, Korea

  2. CHAIN EXTENDER AND EMULSIFIER APPLICATION IN IRON ORE FLOTATION

    Directory of Open Access Journals (Sweden)

    José Pedro da Silva

    2013-06-01

    Full Text Available The present study aims to evaluate the reverse flotation performance of iron ore, using collector (amine, in the presence and absence of chain extender (diesel oil and emulsifier (sodium lauryl sulfate.Six tests were realized with duplicate. Tests using amine, diesel oil and sodium lauryl sulphate show the better results, with metallurgical recovery of 91.82% and the concentrate silica equal 1.68%. Thus, it is found that the use of emulsifier and chain extender together with the amine, shows better results in the flotation, in terms of metal recovery and selectivity, when compared to using only amine or amine and diesel oil.

  3. HIGH CONSISTENCY PULPING OF OLD NEWSPRINT AND ITS FLOTATION PROPERTIES

    Institute of Scientific and Technical Information of China (English)

    Chunhui Zhang; Menghua Qin

    2004-01-01

    The mechanical and chemical effect on the pulping properties of the old newsprint was studied using a FORMAX Micro-Maelstrom Laboratory Pulper, and the flotation conditions such as velocity of air flow,air pressure and flotation time were also discussed with a FORMAX Deink Cell. The results show that sodium hydroxide, sodium silicate, hydrogen peroxide and deinking agent are the key factors in the chemical effect, and pulping consistency is more important than pulping time and rotation speed in the mechanical effect during the high consistency pulping of the ONP. In general, the chemical effect has a greater influence on the deinked pulp properties than the mechanical effect.

  4. Upgrading graphite by flotation at Bogala Mines in Sri Lanka

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Graphite is naturally floatable due to its hydrophobic property and also soft and smears on other gangue particles, rendering the gangue more or less floatable too. Due to this reason it is important to concentrate on areas such as suitable flotation reagents, depression agents, pH modifiers, and particle size to be fed during the process, The paper surveys and analyses the suitable particle size to be fed to achieve high-grade concentrate. According to the work carried out the author suggested the ideal cost effective flotation flow sheet for improved results at Bogala Mines in Sri Lanka.

  5. Desulfurization of coal by an electrochemical-reduction flotation technique

    Institute of Scientific and Technical Information of China (English)

    ZHAO Wei; XU Wen-juan; ZHONG Shi-teng; ZONG Zhi-min

    2008-01-01

    The optimum conditions for sulfur removal from coal by electrochemical reduction flotation in an aqueous NaCI solution were determined from orthogonal experiments. The effect of electrolytic conditions on the desulfurization ratio was also studied.The electrochemical-reduction processed coal was examined by X-ray diffraction, Fourier transform infrared spectroscopy and wet chemical analysis. The results show that electrochemical reduction converts hydrophobic pyrite in Nantong coal into hydrophilic FeS and S2 and leads to an increase in the concentration of hydroxyl groups and aliphatic moieties and a corresponding decrease in carboxyl and carbonyl groups, which enhances the flotation desulfurization of the coal.

  6. THE DEPRESSION OF PYRITE FLOTATION BY THIOBACILLUS FERROOXIDANS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The experimental studies on the microbial flotation of a pure pyrite sample using Thiobacillus ferrooxidans was conducted in the laboratory. The results indicate that Thiobacillus ferrooaidans has strong depression effect on the flotation of pyrite. Thiobacillus f errooxidans can adsorb on the surface of pyrite in a very short time (a few min. ), changing the surface from hydrophobic into hydrophilic and making the pyrite particles to lose their floatability. Therefore, Thiobacillus ferrooxidans is an effective microbial depressant of pyrite. It has also been pointed out that the depression of pyrite by Thiobacillus ferrooxidans is caused by the adsorption of the microbial colloids, but not by the oxidation effect.

  7. HIGH CONSISTENCY PULPING OF OLD NEWSPRINT AND ITS FLOTATION PROPERTIES

    Institute of Scientific and Technical Information of China (English)

    ChunhuiZhang; MenghuaQin

    2004-01-01

    The mechanical and chemical effect on the pulping properties of the old newsprint was studied using a FORMAX Micro-Maelstrom Laboratory Pulper, and the flotation conditions such as velocity of air flow, air pressure and flotation time were also discussed with a FORMAX Deink Cell The results show that sodium hydroxide, sodium silicate, hydrogen peroxide and deinking agent are the key factors in the chemical effect, and pulping consistency is more important than pulping time and rotation speed in the mechanical effect during the high consistency pulping of the ONP. In general, the chemical effect has a greater influence on the deinked pulp properties than the mechanical effect.

  8. Mechanism of separating pyrite and dolomite by flotation

    Institute of Scientific and Technical Information of China (English)

    Anping Liu; Wen Ni; Wei Wu

    2007-01-01

    To study the mechanism of separating pyrite and dolomite by flotation, the acting mechanisms of WHL depressor and both the minerals were studied by means of thermogravimetric and differential thermal analysis (TG-DTA), Fourier transform infrareddiffuse reflection spectroscopy (FTIR-DRS), and X-ray photoelectron spectroscopy (XPS). The results indicated that WHL formed metal salts with metal ions dissolved in water from dolomite and pyrite, which then deposited on their surfaces. Both of the minerals could be depressed by WHL. In the process of flotation, sulfur was created besides the WHL being absorbed on the surface of the sulfur concentrate, and its recovery rate was slightly affected.

  9. A Study of the Optimal Model of the Flotation Kinetics of Copper Slag from Copper Mine BOR

    Science.gov (United States)

    Stanojlović, Rodoljub D.; Sokolović, Jovica M.

    2014-10-01

    In this study the effect of mixtures of copper slag and flotation tailings from copper mine Bor, Serbia on the flotation results of copper recovery and flotation kinetics parameters in a batch flotation cell has been investigated. By simultaneous adding old flotation tailings in the ball mill at the rate of 9%, it is possible to increase copper recovery for about 20%. These results are compared with obtained copper recovery of pure copper slag. The results of batch flotation test were fitted by MatLab software for modeling the first-order flotation kinetics in order to determine kinetics parameters and define an optimal model of the flotation kinetics. Six kinetic models are tested on the batch flotation copper recovery against flotation time. All models showed good correlation, however the modified Kelsall model provided the best fit.

  10. Hydrocarbon-oil encapsulated bubble flotation of fine coal using 3-in. ID flotation column. Technical progress report for the eleventh quarter, April 1--June 30, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Peng, F.F.

    1996-05-01

    There are four modes of the collector dispersion techniques. They are (1) direct liquid additions and stirring, (2) ultrasonic energy collector dispersion, (3) atomized collector dispersion, and (4) gasified collector transported in air stream. Among those collector dispersion techniques, the technique using the gasified collector transported in air phase can be used to enhance the flotation performance with substantial reduction in collector usage and selectivity, compared to the flotation using direct liquid addition (and mechanical agitation) technique. In this phase of study, two modes of collector addition techniques including gasified collector transported in gas phase and direct collector addition techniques were applied in the column flotation to demonstrate the selectivity of utilizing the hydrocarbon-oil encapsulated air bubbles in the fine coal flotation process. The 1-in. ID flotation column was used to scale-up to 3-in. ID flotation column. The initial starting point to operate the 3-in ID flotation column were determined using both 1-in. and 3-in. flotation columns based on the three phases of work plans and experiment design. A 3-in. flotation column was used to evaluate two modes of collector dispersion and addition techniques on the recovery and grade of fine coals using various ranks of coal.

  11. Measuring turbulence in a flotation cell using electrical resistance tomography

    Science.gov (United States)

    Meng, Jun; Xie, Weiguo; Runge, Kym; Bradshaw, Dee

    2015-11-01

    Measuring turbulence in an industrial flotation environment has long been problematic due to the opaque, aggressive, and abrasive three-phase environment in a flotation cell. One of the promising measurement techniques is electrical resistance tomography (ERT). By measuring the conductivity distribution across a measurement area, ERT has been adopted by many researchers to monitor and investigate many processes involving multiphase flows. In the research outlined in this paper, a compact ERT probe was built and then used to measure the conductivity distribution within a 60 l flotation cell operated with water and air. Two approaches were then developed to process the ERT data and estimate turbulence-related parameters. One is a conductivity variance method and the other is based on the Green-Kubo relations. Both rely on and use the fluctuation in the ERT measurement caused by bubbles moving through the measurement area changing the density of the fluid. The results from both approaches were validated by comparing the results produced by the ERT probe in a 60l flotation cell operated at different air rates and impeller speeds to that measured using an alternative turbulence measurement device. The second approach is considered superior to the first as the first requires the development of auxiliary information which would not usually be known for a new system.

  12. 33 CFR 142.45 - Personal flotation devices.

    Science.gov (United States)

    2010-07-01

    ... fall, they would likely fall into water, shall wear a work vest that meets the requirements of 33 CFR 146.20 or a life preserver that meets the requirements of 46 CFR 160.002, 160.005, or 160.055, except... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Personal flotation devices....

  13. Coal surface control for advanced fine coal flotation

    Energy Technology Data Exchange (ETDEWEB)

    Fuerstenau, D.W.; Sastry, K.V.S.; Hanson, J.S.; Harris, G.; Sotillo, F.; Diao, J. (California Univ., Berkeley, CA (USA)); Somasundaran, P.; Harris, C.C.; Vasudevan, T.; Liu, D.; Li, C. (Columbia Univ., New York, NY (USA)); Hu, Weibai; Zou, Y.; Chen, W. (Utah Univ., Salt Lake City, UT (USA)); Choudhry, V.; Sehgal, R.; Ghosh, A. (Praxis Engineers, Inc., Milpitas, CA (USA))

    1990-08-15

    The primary objective of this research project is to develop advanced flotation methods for coal cleaning in order to achieve near total pyritic-sulfur removal at 90% Btu recovery, using coal samples procured from six major US coal seams. Concomitantly, the ash content of these coals is to be reduced to 6% or less. Work this quarter concentrated on the following: washability studies, which included particle size distribution of the washability samples, and chemical analysis of washability test samples; characterization studies of induction time measurements, correlation between yield, combustible-material recovery (CMR), and heating-value recovery (HVR), and QA/QC for standard flotation tests and coal analyses; surface modification and control including testing of surface-modifying reagents, restoration of hydrophobicity to lab-oxidized coals, pH effects on coal flotation, and depression of pyritic sulfur in which pyrite depression with calcium cyanide and pyrite depression with xanthated reagents was investigated; flotation optimization and circuitry included staged reagent addition, cleaning and scavenging, and scavenging and middling recycling. Weathering studies are also discussed. 19 figs., 28 tabs.

  14. Selective flotation of fossil resin from western coal

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, G.F.; Miller, J.D.

    1992-03-20

    The test program has demonstrated that: (1) technically, the new flotation technologies discovered at the University of Utah and then improved upon by Advanced Processing Technologies, Inc. provide a highly efficient means to selectively recover fossil resin from coal. The proof-of-concept continuous flotation circuit resulted in fossil resin recovery with the same separation efficiency as was obtained from laboratory bench-scale testing (more than 80% recovery at about 80% concentrate grade); and (2) economically, the selective flotation process has been shown to be sufficiently profitable to justify the development of a fossil resin industry based on this new flotation process. The proof-of-concept testing has resulted in significant interest from several coal mining companies and has sparked the desire of local and state government to establish a fossil resin industry in the Wasatch Plateau coal field. In this view, the results from the current proof-of-concept testing program have been successful. This special report provides theoretical and analytical data on some surface chemistry work pertinent to fossil resin characterization, and other efforts carried out during the past months.

  15. Zeta potentials in the flotation of oxide and silicate minerals.

    Science.gov (United States)

    Fuerstenau, D W; Pradip

    2005-06-30

    Adsorption of collectors and modifying reagents in the flotation of oxide and silicate minerals is controlled by the electrical double layer at the mineral-water interface. In systems where the collector is physically adsorbed, flotation with anionic or cationic collectors depends on the mineral surface being charged oppositely. Adjusting the pH of the system can enhance or prevent the flotation of a mineral. Thus, the point of zero charge (PZC) of the mineral is the most important property of a mineral in such systems. The length of the hydrocarbon chain of the collector is important because of chain-chain association enhances the adsorption once the surfactant ions aggregate to form hemimicelles at the surface. Strongly chemisorbing collectors are able to induce flotation even when collector and the mineral surface are charged similarly, but raising the pH sufficiently above the PZC can repel chemisorbing collectors from the mineral surface. Zeta potentials can be used to delineate interfacial phenomena in these various systems.

  16. Remediation of fine fractions of dredged sediments by flotation

    NARCIS (Netherlands)

    Mulleneers, H.A.E.; Mark, van der B.; Geraets, J.; Gelder, van B.; Bruning, H.; Rulkens, W.H.; Koopal, L.K.

    2002-01-01

    In the Netherlands, large quantities of contaminated dredged sludge have to be deposited or treated in the near future. Because of the large amounts of small particles involved, successful treatment is difficult. In this study a new flotation method on laboratory scale was used as an alternative

  17. Selective recovery of micrometer bioparticles using aggregation and air flotation

    NARCIS (Netherlands)

    Van Hee, P.

    2006-01-01

    Air flotation is a separation technique that makes use of the air-water interface for separation of particles and molecules from mixtures. This thesis discusses its use for separation of bioparticle mixtures. Particulate bioproducts, such as crystals, inclusion bodies, virus-like particles and

  18. Study of flotation performance of kerosene after ultrasonic emulsified

    Energy Technology Data Exchange (ETDEWEB)

    Kang Wen-ze; Wang Hui; Kong Xiao-hong; Lu Yu-ting; Hu Jung [Heilongjiang Institute of Science and Technology, Harbin (China). School of Resource and Environmental Engineering

    2008-01-15

    A Setaram calorimeter, a contact angle gauge DCAT21, surface tension apparatus and a Leica electron microscope were used to study the nature of emulsified kerosene and kerosene and their effects on slime. Batch flotation tests were carried out. The results show that the particle diameter of emulsified kerosene, the dispersibility in water, the wetting heat with slime, changing contact angle and decreasing gas-solution interfacial tension are all better than those of kerosene. The consumption of emulsified kerosene is only one third of that of kerosene when equivalent yields of clean coal are obtained. The flotation speed of emulsified kerosene is faster than that of kerosene. The yield of clean coal with emulsified kerosene is higher than that of kerosene by 7.38% and the ash content of clean coal emulsified in kerosene is lower than that of kerosene by 0.98% when equivalent amounts of the two reagents are used in the flotation process. The study shows that flotation selectivity and efficiency of emulsified kerosene are all higher than those of kerosene and the consumption of reagent is lower than that of kerosene. 15 refs., 3 figs., 5 tabs.

  19. 21 CFR 890.5170 - Powered flotation therapy bed.

    Science.gov (United States)

    2010-04-01

    ... intended for medical purposes to treat or prevent a patient's bedsores, to treat severe or extensive burns... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Powered flotation therapy bed. 890.5170 Section... (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Therapeutic Devices §...

  20. Removal of fluoride from semiconductor wastewater by electrocoagulation-flotation.

    Science.gov (United States)

    Hu, C Y; Lo, S L; Kuan, W H; Lee, Y D

    2005-03-01

    This work employs an anodic surfactant, sodium dodecyl sulfate (SDS), to improve the flotation performance of the electrocoagulation-flotation (ECF) process to treated fluoride containing semiconductor wastewater following calcium precipitation. The dissolved fluoride ions and CaF(2) particles in the wastewater after calcium precipitation were effectively removed in the ECF process simultaneously. The dosage of SDS required for ECF was much less than those for dispersed air flotation (DiAF) or dissolved air flotation (DAF) processes because the CaF(2) particles can be collected by hydro-fluoro-aluminum flocs in ECF. Thus, SDS only served as a frother to make the bubbles tiny and stable in the ECF defluoridation process. The interference of co-existing anions can be overcome by increasing the dosage of calcium ions and SDS. The optimum initial acidity for ECF is close to the initial fluoride concentration after calcium precipitation; the amount of SS removed dropped rapidly if the initial acidity exceeded the optimal value because the surface charge of the hydro-fluoro-aluminum particles increased. The initial acidity of the wastewater after calcium precipitation can be modified by changing the [Ca(OH)(2)]/[Ca(2+)](T) ratio and the appropriate ratio is approximately given by the acid dissociation constant of hydrofluoric acid and the initial pH of the wastewater before calcium precipitation.

  1. FLOTATION OF Cu(Ⅱ) BY COLLOIDAL GAS APHRONS(CGA)%利用胶质气体泡沫气浮Cu(Ⅱ)

    Institute of Scientific and Technical Information of China (English)

    王运东; 温涵真; 戴猷元

    2001-01-01

    Colloidal gas aphrons(CGAs) were first defined by Sebba(J.Colloid Interface Sci.,1971,35(4):643) as micro bubbles(25—300*μm).These microbubbles do not coalesce easily and are markedly different from conventional soap bubbles in their stability and flow properties.CGAs are composed of a gaseous inner core surrounded by a thin surfactant film, which are created by intense stirring of a surfactant solution. CGA dispersion typically contains about 65% gas. CGA suspensions have viscosity similar to water, which make them suitable for pumping without deterioration in quality. Two important considerations in the application of CGA suspensions are: ① their colloidal size, resulting in a large surface area to volume ratio, and ② the existence of a double film of surfactant encapsulating the gas that retards the coalescence of the bubble. CGA suspensions are found very effective for separating hydrophobic organic compounds and heavy metal ions. In this paper, flotation of Cu(Ⅱ) by colloidal gas aphrons has been conducted in order to explore a new method for separating heavy metal ions from dilute solution. The effects of CGA flow rate, amounts of CGA introduced to the system, surfactant concentration on the flotation efficiency have been systematically investigated. The optimum flotation condition is determined. The results show that flotation efficiency at pH=5—6 has an optimum value to CGA flow rate and amount. When pH is greater than 7, the flotation efficiency can be as high as 99% at the optimum condition.

  2. Experiment Study of Flotation Column in Phosphate Rock Flotation%浮选柱在磷矿选矿中的应用研究

    Institute of Scientific and Technical Information of China (English)

    彭操; 刘江林

    2012-01-01

    采用浮选柱设备进行磷矿的选矿实验研究。通过化学法分析磷矿的矿物特性,采用浮选柱分选技术,开展磷矿精选试验。结果表明,在充气量为6~10 L/h,冲洗水2~3 L/h可以得到w(P2O5)=30%以上的磷精矿。%the applied situation of the domestic and foreign flotation column in phosphate rock flotation was introduced. According to the mineral characteristics of phosphate rock, we adopted the flotation column separation technology and carried out the phosphate separation experiment. The experimental result indicated that the effects were better and the product quality was stable. So the flotation column separation technology has a good application prospect in phosphate rock flotation.

  3. An overview of oil-water separation using gas flotation systems.

    Science.gov (United States)

    Saththasivam, Jayaprakash; Loganathan, Kavithaa; Sarp, Sarper

    2016-02-01

    Oil concentration levels in municipal waste water effluent streams are stringently regulated in most parts of the world. Apart from municipal waste, stricter oil/grease discharge limits are also enforced in oil and gas sectors as large volumes of produced water is being discharged to open ocean. One of the feasible, practical and established methods to remove oil substances from waste water sources is by gas flotation. In this overview, gas flotation technologies, namely dissolved and induced flotation systems, are discussed. Physico-chemical interaction between oil-water-gas during flotation is also summarized. In addition to a brief review on design advancements in flotation systems, enhancement of flotation efficiency by using pre-treatment methods, particularly coagulation-flocculation, is also presented.

  4. Research on Pressure Drop Performance of the Packing-Flotation Column

    Institute of Scientific and Technical Information of China (English)

    LIU Jiong-tian; ZHANG Min; LI Yan-feng; LU Yang

    2006-01-01

    A packing-flotation column was proposed to optimize the flotation environment A research system was established using a 100 mm diameter cyclonic micro-bubble flotation column to study fluid properties. Dry-plate and wet- plate pressure drops were studied and the corresponding pressure drop equations developed. The results show that the dry-plate pressure drop of the packing cyclonic micro-bubble flotation column is 10-15 times less than that of the chemical tower, which is principally shown in its relatively small resistance coefficient, 0.0207. The wet-plate pressure drop is 2-3 times higher than that of the chemical tower, which is largely caused by the separation materials and characteristics of the equipment. With flotation, the greater the pressure drop, the better the flotation environment.

  5. A review of rare earth minerals flotation:Monazite and xenotime

    Institute of Scientific and Technical Information of China (English)

    Chelgani S. Chehreh; Rudolph M.; Leistner T.; Gutzmer J.; Peuker Urs A.

    2015-01-01

    This paper reviews rare earth minerals (monazite and xenotime) separation by flotation. A wide range of monazite and xenotime flotation test results are summarized including:reasons of variation in the point of zero charges on these minerals, the effects of various flotation conditions on zeta potential of monazite and xenotime, interactions of collectors and depressants on the surface of these minerals during flotation separation, relationship between surface chemistry of the minerals and different types of collector adsorptions and effects of the conditioning temperature on flotation of rare earth minerals. This review collects various approaches for the selective separation of monazite and xenotime by flotation and gives perspectives for further research in the future.

  6. Bench-scale testing of on-line control of column flotation using a novel analyzer. Revised final report, [October 1992--October 1993]: Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    1993-10-27

    The main advantage of the project is that it allowed PTI to gain knowledge and experience about the proper approach, methods and hardware required to properly optimize and control column flotation performance. Many operational problems were incurred during the project, some of that PTI was able to solve during the project and other that must be overcome as the technology is further developed and commercialized. The key operating problems experienced with the KEN-FLOTE{sup TM} Column that must be further researched and overcome include: (1)The low concentrate solids content which limited the throughput capacity of the column, due to high froth washing requirements. The low concentrate solids content also lead to difficulty obtaining accurate On-Line Monitor measurements, due to the poor measurement sensitivity obtained with low solids content samples (particularly less than 5.0 wt %). (2) The higher-than-anticipated reagent dosages that undoubtedly contributed to the low solids content listed above, and also caused foaming problems within PTI`s On-Line Monitor. A defoaming reagent addition (Nalco 7810) was required to provide consistent sample size and reproducible On-Line Monitor counts for the concentrate samples collected within the circuit. PTI and UK`s CAER staff will continue to research alternative column design, particularly alternative air bubble generation and air distribution systems, to try to maximize column concentrate solids content while reducing reagent dosage requirements. In addition to the KEN-FLOTE{sup TM} Column operation there were also a number of hardware problems with PTI`s On-Line Quality Monitor that must be remedied for future commercial installations.

  7. Statistical Evaluation and Optimization of Factors Affecting the Leaching Performance of Copper Flotation Waste

    OpenAIRE

    Semra Çoruh; Sermin Elevli; Feza Geyikçi

    2012-01-01

    Copper flotation waste is an industrial by-product material produced from the process of manufacturing copper. The main concern with respect to landfilling of copper flotation waste is the release of elements (e.g., salts and heavy metals) when in contact with water, that is, leaching. Copper flotation waste generally contains a significant amount of Cu together with trace elements of other toxic metals, such as Zn, Co, and Pb. The release of heavy metals into the environment has resulted in ...

  8. A new gravity & flotation separator with double-tailing discharge and its beneficiation performance

    Institute of Scientific and Technical Information of China (English)

    YANG Hong-li; FAN Min-qiang

    2012-01-01

    Introduced a new gravity and flotation separator with double-tailing discharge for fine coal,and integrated classification and cyclone scavenging with flotation in an original way.The beneficiation performance of it was good.The results show that the gravity and flotation separator with double-tailing discharge can produce high-quality clean coal of 10.46% ash from fine coal of 35.56% ash.It can discharge the fine and coarse railings separately.

  9. Final flotation waste kinetics of sintering at different heating regimes

    Directory of Open Access Journals (Sweden)

    Cocić Mira

    2016-01-01

    Full Text Available In the copper extraction, especially during the process of flotation enrichment and the pyrometallurgical processing, the waste materials that represent huge polluters of environment are being generated. In order to examine the application of Final flotation waste (FFW in the manufacturing of new materials from the glass-ceramic group phase and mineral composition were examined as well as thermal properties. FFW kinetics of sintering has been tested at different dyamics (1°C/min, 29°C/min and 43°C/min, in order to find the optimum conditions for sintering with a minimum amount of energy and time consumption. The samples were examined using: X-ray diffraction, X-ray fluorescence analysis, SEM (Scanning Electron Microscopy and thermal microscopy. The best results for the production of glass ceramic materials were obtained during the sintering at heating regime of 29°C/min. [Projekat Ministarstva nauke Republike Srbije, br. 176010

  10. State of the art on ion and precipitate flotation

    Energy Technology Data Exchange (ETDEWEB)

    Jung, In Ha; Yang, Myung Seung; Bae, Ki Kwang; Shon, Jong Sik; Cho, Young Hyun

    1997-08-01

    This report is contained research status of foam separation technique and thus theoretical backgrounds, the kinds of surfactants using for the foam separation technique, their characteristics, general structure and role, surfactant absorption mechanism at liquid/vapor/solid interfaces, effectiveness and efficiency were interpreted with well known models. Ion flotation and precipitate flotation which are applicable for the treatment of very low radioactive liquid wastes were analyzed on the effect of pH, foreign ions, initial concentration of metal ion through the recent presented papers. As the result of technical analysis of foam separation technique, foam separation technique seems to be applicable for the treatment of very low radioactive liquid wastes such as laundry and shower waste. (author). 42 refs., 2 tabs., 37 figs

  11. Degradation of ethyl xanthate in flotation residues by hydrogen peroxide

    Institute of Scientific and Technical Information of China (English)

    陈兴华; 胡岳华; 彭宏; 曹学锋

    2015-01-01

    The degradation behavior of ethyl xanthate (EX) salt was the most widely used collector in sulfide mineral flotation and emission of flotation tailings with residual EX was harmful to environment. In this work, hydrogen peroxide (H2O2) was investigated by UV-visible spectroscopy (UV/Vis) at different pH values from 3 to 12. For pH value from 5 to 12, EX was oxidized into ethyl per xanthate (EPX) by H2O2. Then EPX was further oxidized into thiosulfate (TS) salt rather than ethyl thiocarbonate (ETC) and this step was the reaction-limited step. Then depending on pH values, TS was degraded into sulphate and carbonate salts (pH>7) or elemental sulfur (pH3.0 during test time.

  12. Study on the Axial Dispersion of Liquid in Column Flotation

    Institute of Scientific and Technical Information of China (English)

    周鵾; 曾爱武; 高长宝; 余国琮

    2003-01-01

    An experimental study on the axial dispersion of liquid was carried out in a 0.382-m-ID flotation column packed with different structured packings or free of packings. The correlations of axial Peclet numbers with the liquid and gas superficial Reynolds numbers were developed for various packings. Among the packings tested, it is found that in the column packed with 250Y or 350Y packings the axial dispersion is the lowest. The addition of frother can decrease the axial dispersion. By the simulation analysis of the one-dimension dispersion model of packed flotation column, it is found that small axial dispersion, high collection rate constant and low axial liquid velocity can increase the collection zone recovery.

  13. The effect of hard coal density on its flotation performance

    Directory of Open Access Journals (Sweden)

    Ewa Małysa

    2005-11-01

    Full Text Available Hard coal flotation depends on many factors, one of which is the density of the grains floated. The heavier the grain, the greater the gravitational force that counteracts the force of adhesion between the grain and an air bubble, and the lower the probability of forming the grain-air bubble aggregate. This paper presents the results of a study on the effect of grain density on hard coal flotation. To eliminate the effect of grain size, densimetric fractions of very similar grain sizes were floated. Significant differences in the floatability of grains of the same size but of different densities were found. The floatability of coal grains dramatically decreased with their density

  14. Particle Residence Time in Column Flotation Based on Cyclonic Separation

    Institute of Scientific and Technical Information of China (English)

    ZHOU Xiao-hua; LIU Jiong-tian

    2007-01-01

    The cyclonic static micro-bubble column flotation (FCSMC) is an effective separation device for fine particle treatment. The high mineralization rate and short flotation time of this equipment can be attributed to its unique cyclonic force field. It also has been observed that the presence of a cyclonic force field leads to a lower bottom separation size limit and a reduction of unselective entrainment. The collection zone of the column is considered to consist of two parts, a column separation zone and a cyclonic zone. Total recovery of the collection zone was developed. For our study, we analyzed the particle movement in the cyclonic zone. Particle residence time equations for the cyclonic zone were derived by force analysis. Results obtained in this study provide a theoretical foundation for the design and scale-up of the FCSMC.

  15. Flotation bubble image segmentation based on seed region boundary growing

    Institute of Scientific and Technical Information of China (English)

    Zhang Guoying; Zhu Hong; Xu Ning

    2011-01-01

    Segmenting blurred and conglutinated bubbles in a flotation image is done using a new segmentation method based on Seed Region and Boundary Growing (SRBG). Bright pixels located on bubble tops were extracted as the seed regions. Seed boundaries are divided into four curves: left-top, right-top, rightbottom, and left-bottom. Bubbles are segmented from the seed boundary by moving these curves to the bubble boundaries along the corresponding directions. The SRBG method can remove noisy areas and it avoids over- and under-segmentation problems. Each bubble is segmented separately rather than segmenting the entire flotation image. The segmentation results from the SRBG method are more accurate than those from the Watershed algorithm.

  16. Flotation separation of marmatite from pyrrhotite using DMPS as depressant

    Institute of Scientific and Technical Information of China (English)

    SUN Wei; LIU Run-qing; CAO Xue-feng; HU Yue-hua

    2006-01-01

    Mercapto organic compound DMPS was used as the depressant for separation of copper activated marmatite from pyrrhotite in the presence of butyl xanthate. The flotation tests of single mineral show that DMPS has strong depressing effect on pyrrhotite in the absence and presence of copper ion, but has activated effect on marmatite in the presence of copper ion. The floatability of marmatite is improved in the pH range of 2-12. The flotation test of mixture mineral shows that copper-activated marmatite can be separated efficiently from pyrrhotite using DMPS as depressant. Infrared adsorption spectra demonstrate that there are a number of function groups such as -SH and -SO3 in the molecular structure ofDMPS. Xanthate and DMPS compete in their adsorption on sulfide minerals.

  17. Coal Recycling from Tailings using Flotation with 2-Level Experimental Design Techniques

    Directory of Open Access Journals (Sweden)

    Sajjad Jannesar Malakooti

    2012-12-01

    Full Text Available In this study, the possibility of producing coal with less than 11% ash from tailings of flotation process was investigated. The effect of six flotation parameters: collector type, collector consumption, frother type, frother consumption, pulp density and mixing rate were studied on a sample from a tailing dam. A software based experimental design approach (DX7 was applied to determine and model effective parameters as well as flotation optimization through fractional factorial. It was shown that collector type and flotation machine mixing rate were the most effective parameters on ash content of concentrate. The results indicated that the production of a desired ash content concentrate, i.e.

  18. Kinetics aspects of minerals flotation; Aspectos cineticos de la flotacion de minerales

    Energy Technology Data Exchange (ETDEWEB)

    Bermudez de Castro, F.H.; Navarro Gilz, P. [Dpto. de Ingenieria Quimica, Facultad de Ciencias, Universidad de Granada (Spain)

    1997-06-01

    The velocity of flotation constants for celestine and calcite has been determined using sodium lauril sulphate as collector agent. A mechanic flotation cell has been used testing on pure minerals in a sized range from 80 to-200 A.S.T. meshes. The results show that the velocity of flotation is very high for celestine as well as for calcite, which has been confirmed not for only by the fact that is less than 2 minutes the recovery maximum for both minerals, has been overtake but also for the obtained values of the complex velocity of flotation constant. (Author) 11 refs.

  19. Comparative results of copper flotation from smelter slag and granulated smelter slag

    OpenAIRE

    Milanović, Dragan; Stanujkić, Dragiša; Ignjatović, Miroslav R.

    2013-01-01

    Smelter slag is obtained in the process of metallurgical converting of copper concentrate in the Smelter Plant in Bor, Serbia. Today, the reserves of this material are evaluated at about more of a year, with the average copper content of 0.6-0.9%. Production of copper concentrate by flotation of smelter slag has started in 2001. Flotation concentrate goes to the Copper Smelter once more for production of copper cathodes and the rough flotation tailings go to the flotation tailing dump. Copper...

  20. Adsorption behavior of Pb2+ and Cd2+ ions on bauxite flotation tailings

    Institute of Scientific and Technical Information of China (English)

    WANG Yu-hua; LAN Ye; HUANG Chuan-bing

    2008-01-01

    The adsorption behavior of Pb2+ and Cd2+ ions on bauxite flotation railings was investigated to demonstrate the adsorptivity of the bauxite flotation tailings. The adsorption percentage of Pb2+ and Cd2+ ions as a function of adsorbent dosage, solution pH value and shaking time were determined by batch experiments. The maximum adsorption percentage of 99.93% for Pb2+ ions and 99.75% for Cd2+ ions were obtained by using bauxite flotation railings as adsorbent. The methods, such as zeta potentials, specific surface area measurements and the analysis of adsorption kinetics, were introduced to analyze the adsorption mechanisms of the Pb2+ ions on bauxite flotation tailings. The isoelectric point of bauxite flotation railings shifts from 3.6 to 5.6 in the presence of Pb2+ ions. The specific surface area of bauxite flotation tailings changes from 12.57 to 20.63 m2/g after the adsorption of Pb2+ ions. These results indicate that a specific adsorption of the cation species happens on the surface of bauxite flotation tailings. Adsorption data of Pb2+ ions on the surface of bauxite flotation tailings can be well described by Langmuir model, and the pseudo-second-order kinetic model provides the best correlation for the adsorption data of Pb2+ and Cd2+ ions on bauxite flotation railings.

  1. Flotation: A promising microalgae harvesting and dewatering technology for biofuels production.

    Science.gov (United States)

    Ndikubwimana, Theoneste; Chang, Jingyu; Xiao, Zongyuan; Shao, Wenyao; Zeng, Xianhai; Ng, I-Son; Lu, Yinghua

    2016-03-01

    Microalgal biomass as renewable energy source is believed to be of great potential for reliable and sustainable biofuels production. However, microalgal biomass production is pinned by harvesting and dewatering stage thus hindering the developing and growing microalgae biotechnology industries. Flotation technology applied in mineral industry could be potentially applied in microalgae harvesting and dewatering, however substantial knowledge on different flotation units is essential. This paper presents an overview on different flotation units as promising cost-effective technologies for microalgae harvesting thus bestowing for further research in development and commercialization of microalgae based biofuels. Dispersed air flotation was found to be less energy consuming. Moreover, Jameson cell flotation and dispersed ozone flotation are believed to be energy efficient microalgae flotation approaches. Microalgae harvesting and dewatering by flotation is still at embryonic stage, therefore extended studies with the focus on life cycle assessment, sustainability of the flotation unit, optimization of the operating parameters using different algal species is imperative. Though there are a number of challenges in microalgae harvesting and dewatering, with well designed and developed cultivation, harvesting/dewatering, extraction and conversion technologies, progressively, microalgae technology will be of great potential for biological carbon sequestration, biofuels and biochemicals production.

  2. Sulphidization flotation for recovery of lead and zinc from oxide-sulfide ores

    Institute of Scientific and Technical Information of China (English)

    FA Keqing; Jan D.Miller; JIANG Tao; LI Guang-hui

    2005-01-01

    A new flowsheet was developed to recover the valuable minerals from oxide or oxide-sulfide ores of lead and zinc. The flowsheet consisted of flotation of sulfide minerals, desliming and sulphidization-flotation of oxide minerals. The corresponding reagent system and techniques to the flowsheet were investigated. Batch and continuous tests show that the dosage of sodium sulfide, temperature, and collector type are main affecting factors on the recovery of smithsonite and cerussite. For the flotation of cerussite, there is an appropriate dosage of sodium sulfide at which the recovery reaches its maximum value. The required sodium sulfide for smithsonite flotation is higher than that for cerussite and the recovery of smithsonite flotation increases with the dosage of sodium sulfide at low level and becomes insensitive at high dosage. The appropriate temperature for smithsonite and cerussite flotation is found to be 25 - 40 ℃. Amines are found to be the effective collectors for the flotation of smithsonite after sulphidization. Investigation also shows that desliming prior to sulphidization-flotation is essential to the effective recovery of smithsonite and cerussite, and the desliming process of two-stage hydrocyclon is well feasible and effective for the treatment of lead-zinc oxide ores. A further treatment on the cerussite flotation concentrate by shaking table is proposed to obtain higher lead grade.

  3. Parametric study and simulation of microbubble column flotation

    OpenAIRE

    1991-01-01

    A study based on a statistically designed set of experiments (Box-Behnken design) has been conducted to determine the optimum conditions for advanced physical fine coal cleaning using microbubble column flotation. The dependent variables in these experiments were mass yield and product quality (ash, sulfur and btu), while the independent variables were feed solids content, collector dosage, frother dosage, feed rate, aeration rate, and wash water rate. The most important operating parameters ...

  4. ADVANCES IN ESTIMATION AND CONTROL FOR FLOTATION COLUMNS

    OpenAIRE

    2010-01-01

    Flotation is multivariable process exhibiting uncertain and nonlinear dynamics as well as being perturbed by unmeasured disturbances. Optimization of this process is therefore a complex undertaking. Although real-time optimization (RTO) techniques for maximizing an objective function are aailable, steady-state assumptions in processes being frequently acted upon by unmeasured distrubances, strongly limit the optimization frequency, hierachical control systems allow to efficiently dealing with...

  5. Heterocoagulation of chalcopyrite and pyrite minerals in flotation separation.

    Science.gov (United States)

    Mitchell, Timothy K; Nguyen, Anh V; Evans, Geoffrey M

    2005-06-30

    Heterocoagulation between various fine mineral particles contained within a mineral suspension with different structural and surface chemistry can interfere with the ability of the flotation processes to selectively separate the minerals involved. This paper examines the interactions between chalcopyrite (a copper mineral) and pyrite (an iron mineral often bearing gold) as they approach each other in suspensions with added chemicals, and relates the results to the experimental data for the flotation recovery and selectivity. The heterocoagulation was experimentally studied using the electrophoretic light scattering (ELS) technique and was modelled by incorporating colloidal forces, including the van der Waals, electrostatic double layer and hydrophobic forces. The ELS results indicated that pyrite has a positive zeta potential (zeta) up to its isoelectric point (IEP) at approximately pH 2.2, while chalcopyrite has a positive zeta up to its IEP at approximately pH 5.5. This produces heterocoagulation of chalcopyrite with pyrite between pH 2.2 and pH 5.5. The heterocoagulation was confirmed by the ELS spectra measured with a ZetaPlus instrument from Brookhaven and by small-scale flotation experiments.

  6. Evaluation of flotation results using rubidium ion exchange

    Energy Technology Data Exchange (ETDEWEB)

    Fujimoto, H.; Matsukata, M.; Ueyama, K. [Osaka University, Osaka (Japan). Graduate School of Engineering

    1999-08-01

    Coal particles contain oxygen functional groups such as hydroxyl, carbonyl, and carboxyl, and mineral matters that contribute surface hydrophilicity. Their occurrence varies considerably from coal to coal, hence the characteristics of column flotation changes from coal to coal. It was expected that the characteristics of column flotation could be simply evaluated by using the area fraction of oxygen functional group sites on the exterior surface of the coal particles. Column flotation experiments on coals of different rank were carried out. The order of carbonaceous materials recovery was found to be Tyanfu (bituminous) {gt} Shanxi (anthracite) {gt} Blair Athol (bituminous) {gt} Daton (bituminous) {gt} Illinois (brown coal). The area fraction of hydroxyl group on the exterior surface of the coal particles, alpha (ex-OH), and that in the coal particles, alpha (in-OH) was also evaluaed. For Daton coal, the value of alpha (ex-OH) was larger than that of alpha (in-OH). It means that Daton coal was slightly oxidized. The order of carbonaceous materials recovery was inconsistent with that of alpha (ex-OH) for the three kinds of bituminous coal. For Shanxi anthracite coal, the floatability is evaluated by considering the wettability of the hydrophobic sites as well as the hydrophillic sites.

  7. Potential control flotation of galena in strong alkaline media

    Institute of Scientific and Technical Information of China (English)

    顾帼华; 胡岳华; 邱冠周; 王晖; 王淀佐

    2002-01-01

    The electrochemical oxidation of galena in collectorless and collector flotation systems, particularly in strong alkaline media, was studied. The results show that, with pH value higher than 12.5 and potentials below 0.17 V, the oxidation products of galena are elemental sulfur and HPbO-2. Elemental sulfur was present on the mineral surface in excess of oxidized lead species due to dissolution of HPbO-2, which is beneficial to the flotation of galena. Under the same conditions, sphalerite and pyrite were depressed as a result of significant surface oxidation. Diethyldithiocarbamate (DDTC) was found to be the most suitable collector for galena flotation in strongly alkaline media. The very potential produced hydrophobic PbD2-the surface reaction product of DDTC with galena, is 0 to 0.2 V. Meantime DDTC can depress the surface over-oxidation of galena. Investigations also indicate that, in the range of -0.9 V to 0.6 V, hydrophobic PbD2 can be firmly adsorbed on galena.

  8. Flotation and flocculation chemistry of coal and oxidized coals

    Energy Technology Data Exchange (ETDEWEB)

    Somasundaran, P.

    1990-01-01

    The objective of this research project is to understand the fundamentals involved in the flotation and flocculation of coal and oxidized coals and elucidate mechanisms by which surface interactions between coal and various reagents enhance coal beneficiation. An understanding of the nature of the heterogeneity of coal surfaces arising from the intrinsic distribution of chemical moieties is fundamental to the elucidation of mechanism of coal surface modification and its role in interfacial processes such as flotation, flocculation and agglomeration. A new approach for determining the distribution in surface properties of coal particles was developed in this study and various techniques capable of providing such information were identified. Distributions in surface energy, contact angle and wettability were obtained using novel techniques such as centrifugal immersion and film flotation. Changes in these distributions upon oxidation and surface modifications were monitored and discussed. An approach to the modelling of coal surface site distributions based on thermodynamic information obtained from gas adsorption and immersion calorimetry is proposed. Polyacrylamide and dodecane was used to alter the coal surface. Methanol adsorption was also studied. 62 figs.

  9. Dewatering studies of fine clean coal

    Energy Technology Data Exchange (ETDEWEB)

    Parekh, B.K.

    1991-01-01

    Physical cleaning of ultra-fine coal using an advanced froth flotation technique provides a low ash product, however, the amount of water associated with clean coal is high. Economic removal of water from the froth will be important for commercial applicability of advanced froth flotation processes. The main objective of the present research program is to study and understand the dewatering characteristics of ultra-fine clean coal and to develop the process parameters to effectively reduce the moisture to less than 20 percent in the clean coal product. The research approach under investigation utilizes synergistic effects of metal ions and surfactant to lower the moisture of clean coal using a conventional vacuum dewatering technique. During the last year's effort, it was reported that a combination of metal ion and surfactant provided a 22 percent moisture filter cake.

  10. Dewatering studies of fine clean coal. Technical report, September 1, 1991--November 30, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Parekh, B.K.

    1991-12-31

    Physical cleaning of ultra-fine coal using an advanced froth flotation technique provides a low ash product, however, the amount of water associated with clean coal is high. Economic removal of water from the froth will be important for commercial applicability of advanced froth flotation processes. The main objective of the present research program is to study and understand the dewatering characteristics of ultra-fine clean coal and to develop the process parameters to effectively reduce the moisture to less than 20 percent in the clean coal product. The research approach under investigation utilizes synergistic effects of metal ions and surfactant to lower the moisture of clean coal using a conventional vacuum dewatering technique. During the last year`s effort, it was reported that a combination of metal ion and surfactant provided a 22 percent moisture filter cake.

  11. Dewatering studies of fine clean coal. [Quarterly] technical report, December 1, 1991--February 29, 1992

    Energy Technology Data Exchange (ETDEWEB)

    Parekh, B.K. [Kentucky Univ., Lexington, KY (United States). Center for Applied Energy Research

    1992-08-01

    Physical cleaning of ultra-fine coal using an advanced froth flotation techniques provides a low ash product, however, due to high surface area of particles the amount of water associated with clean coal is high. Economic removal of water from the froth will be important for commercial applicability of advanced froth flotation processes. The main objective of the present research program is to study and understand the dewatering characteristics of ultra-fine clean coal and to develop process parameters to effectively reduce the moisture to less than 20 percent in the clean coal product. The research approach under investigation utilizes synergistic effects of metal ions and surfactant to lower the moisture of clean coal using a conventional vacuum dewatering technique. The studies have identified a combination of metal ion and surfactant found to be effective in providing a 22 percent moisture filter cake.

  12. Frother controlled interfacial phenomena in dynamic systems - a holistic approach

    OpenAIRE

    Jávor, Zoltán

    2014-01-01

    The development of froth flotation has revolutionized the mining industry and greatly increased the mineral production. Flotation reagents are widely applied to control the properties of minerals and bubbles in order to enhance the efficiency of froth flotation. Frothers are one of the flotation reagents employed to improve the performance of the process. The presence of frother molecules aids to reduce bubble size and rise velocity, and enhance froth stability. Although the effect of flotati...

  13. Modeling of behavior of flotoreagent in technical water of mining and processing plant when implementing flotation of iron ores

    OpenAIRE

    Дмитрієва, Олена Олексіївна; Василенко, Ганна Валеріївна

    2013-01-01

    The article has theoretical orientation. It highlights the issues of the modeling of behavior of a flotation reagent in the tailing pit of a mining and processing plant while implementing the flotation tweak of the magnetite concentrate. We have improved the mathematical model of dynamics of the flotation reagent concentration in water flow system of the mining and processing plant, which takes into account the peculiarities of processes of flotation and pelletizing, as well as changes of par...

  14. 46 CFR 180.72 - Personal flotation devices carried in addition to life jackets.

    Science.gov (United States)

    2010-10-01

    ... Jackets § 180.72 Personal flotation devices carried in addition to life jackets. (a) Equipment carried... jackets and must not be substituted for the approved life jackets required to be worn during drills and... 46 Shipping 7 2010-10-01 2010-10-01 false Personal flotation devices carried in addition to life...

  15. Effect of mechanical and chemical clay removals by hydrocyclone and dispersants on coal flotation

    Energy Technology Data Exchange (ETDEWEB)

    Oats, W.J.; Ozdemir, O.; Nguyen, A.V. [University of Queensland, Brisbane, Qld. (Australia). School of Chemical Engineering

    2010-04-15

    Fine minerals, mostly clays, are known to have a detrimental effect on coal flotation. This paper focuses on the effect of mechanical and chemical removals of fine minerals by hydrocyclone and dispersants on coal flotation. The experimental results showed that the flotation recovery slightly increased from medium acidic to medium alkaline ranges. The flotation experiments carried out with dispersants at different dosages showed that the dispersants did not enhance the flotation recovery significantly. However, the removal of the fine fraction from the feed using a hydrocyclone significantly increased the flotation recovery. The bubble-particle attachment tests also indicated that the attachment time between an air bubble and the coal particles increased in the presence of clay particles. These attachment time results clearly showed that the clay particles adversely affected the flotation of coal particles by covering the coal surfaces which reduced the efficiency of bubble-coal attachment. An analysis based on the colloid stability theory showed that the clay coating was governed by the van der Waals attraction and that the double-layer interaction played a secondary role. It was also concluded that the best way to increase the flotation recovery in the presence of clays was to remove these fine minerals by mechanical means such as hydrocylones.

  16. Neural network modelling and prediction of the flotation deinking behaviour of industrial paper recycling processes

    CSIR Research Space (South Africa)

    Pauck, WJ

    2014-01-01

    Full Text Available The removal of ink from recovered papers by flotation deinking is considered to be the “heart” of the paper recycling process. Attempts to model the deinking flotation process from first principles has resulted in complex and not readily usable...

  17. Flotation and adsorption of quaternary ammonium salts collectors on kaolinite of different particle size

    Institute of Scientific and Technical Information of China (English)

    Jiang Hao; Liu Guorong; Hu Yuehua; Xu Longhua; Yu Yawen; Xie Zhen; Chen Haochuan

    2013-01-01

    The flotation behaviors of decyltrimethylammonium (103C),dodecyltrimethylammonium chloride (DTAC),tetradecyltrimethylammonium chloride (TTAC) and cetyltrimethylammonium chloride (CTAC) on kaolinite of different particle size fraction were studied.The adsorbed amount and adsorption isotherms of collectors on kaolinite were determined for painstaking investigation into the adsorption of quaternary amines at kaolinite-water interface by ultraviolet spectrophotometer methods.The flotation results show that the flotation recovery of kaolinite of different particle fraction increases with an increase in pH when 103C,DTAC,TrAC and CTAC are used as collectors.As the concentration of collectors increases,the flotation recovery increases.Particle size of kaolinite has a strong effect on flotation.The flotation recovery of fine kaolinite decreases with the carbon chain of quaternary ammonium salts collectors increasing,while coarse kaolinite is on the contrary.The adsorbed amount tests and adsorption isotherms show that adsorbed amount increases when the particle size of kaolinite increases or when the carbon chain length of quaternary ammonium salts increases.Within the range of flotation collector concentration,the longer the hydrocarbon chain,the more probable to be absolutely adsorbed by fine kaolinite particles and then the lower the collector concentration in the bulk,which leds to lower flotation recovery.

  18. 浮选脱墨时泡沫的稳定性及其带走纤维和填料的问题%Froth stability and fibre and filler entrainment during flotation of toner-printed paper Deinking

    Institute of Scientific and Technical Information of China (English)

    陈嘉翔

    2007-01-01

    介绍了油墨粒子大小和气泡大小与数量及其形成的泡沫的稳定性等对浮选脱墨效率和浮选得率的影响.结果认为:浮选时适当的油墨粒子大小和适当的气泡大小形成稳定的泡沫层,对提高浮选脱墨效率是非常重要的.气泡间的水会带走纤维和填料造成浮选得率降低是值得重视的.

  19. 浮选柱浮选金矿矿泥半工业试验研究%Semi Industrial Test by Analysis of Flotation Column Flotation Gold Slime

    Institute of Scientific and Technical Information of China (English)

    管乐; 高云; 孙日舜

    2013-01-01

    本文介绍了某金矿应用浮选柱浮选矿泥所进行的半工业试验过程及结果分析。通过试验及数据分析,表明了浮选柱适合该金矿浮选矿泥,并能够取得比较好的技术指标。%This paper introduces the application of flotation column flotation gold slime and the analysis of semi industrial test process and result in a gold mine. Through the test and data analysis, it shows that the flotation column for the gold flotation slime, and can better achieve technical index.

  20. Improvement of copper-molybdenum ore beneficiation using a combined flotation and biohydrometallurgy method

    Institute of Scientific and Technical Information of China (English)

    Irina Pestryak; Valery Morozov; Jamsranjav Baatarhuu

    2013-01-01

    The authors present the results of analysis of material composition and experimental investigations of acid and biohydrometallurgical leaching of middlings on grain size,pH level,leaching process duration,temperature and slurry density.The rational parameters of flotation and acid-bacterial leaching of middlings providing an efficient release of valuable components from mineral complexes and recovery to flotation concentrate and leaching solution have been determined.A combined flowsheet and a beneficiation process for bulk flotation middlings of copper-molybdenum ore have been suggested,which include middlings grinding,sulfide minerals flotation,bacterial leaching of sulfide flotation tailings,liquid-phase extraction of dissolved copper and electrolysis of re-extraction eluates.The suggested combined method of cleaning of middlings of copper-molybdenum ores beneficiation provides the total copper recovery increase by 0.8% with a reduction of the cost price of saleable material by 0.5%.

  1. Selective depression behavior of guar gum on talc-type scheelite flotation

    Science.gov (United States)

    Zhang, Yong-zhong; Gu, Guo-hua; Wu, Xiang-bin; Zhao, Kai-le

    2017-08-01

    The depression behavior and mechanism of guar gum on talc-type scheelite flotation were systematically investigated by flotation experiments, adsorption tests, zeta-potential measurements, and infrared spectroscopic analyses. The flotation results for monominerals, mixed minerals, and actual mineral samples indicated that guar gum exhibited much higher selective depression for talc than for scheelite. Bench-scale closed-circuit tests showed that a tungsten concentrate with a WO3 grade of 51.43% and a WO3 recovery of 76.18% was obtained. Adsorption tests, zeta-potential measurements, and infrared spectral analyses confirmed that guar gum absorbed more strongly onto the talc surface than onto the scheelite surface because of chemisorption between guar gum and talc. This chemisorption is responsible for the guar gum's highly selective depression for talc and small depression for scheelite. The flotation results provide technical support for talc-type scheelite flotation.

  2. Supervisory control experience on large industrial flotation columns

    Energy Technology Data Exchange (ETDEWEB)

    Bergh, L.G.; Yianatos, J.B. [Chemical Engineering Dept., Santa Maria Univ., Valparaiso (Chile)

    1999-07-01

    The industrial experience in developing supervisory control systems for flotation columns is discussed. Procedures for diagnosis of instrumentation calibration and maintenance, prior to the implementation of control schemes on top of the distributed control system, are discussed. This strategy contributes to better control by using data validation, by opportunely detecting measurement and operating problems and by consistently coordinating control actions in managing the local control loop setpoints. Examples based on the control systems developed for El Teniente and Salvador concentrators, from Codelco-Chile, are used to illustrate how to relax some of the constraints on the controllability of the process. (author)

  3. Study on the sedimentation capability of bauxite flotation concentrate

    Institute of Scientific and Technical Information of China (English)

    Chen Jianming; Liu Sanjun; Qin Wenqing; Chen Zhiyou; Hu Yuehua

    2008-01-01

    The sedimentation behaviors of bauxite flotation concentrates were investigated at different pH values and floc-eulant dosages.The effects of three types of flocculants( cationic,anionic and non-ionic polyacrylamide flocculants)as well as the moleculax weight of anionic flocculants on the sedimentation of concentrate were studied.It is shown from the experimental results that at the pH 7.0,best sedimentation capability is reached when anionic polyacrylamide flocculant (molecular weight 14 miLlion)is added and the optimal dosage is 30 g/t.

  4. KOMBINASI ULTRAFILTRASI DAN DISSOLVED AIR FLOTATION UNTUK PEMEKATAN MIKROALGA

    Directory of Open Access Journals (Sweden)

    I Nyoman Widiasa

    2014-05-01

    Full Text Available Abstrak Mikroalga merupakan mikroorganisme fotosintetik prokariotik atau eukariotik yang dapat tumbuh dengan cepat. Pemanfaatan mikroalga tidak hanya berorientasi sebagai pakan alami untuk akuakultur, tetapi terus berkembang untuk bahan baku produksi pakan ternak, pigmen warna, bahan farmasi (β-carotene, antibiotik, asam lemak omega-3, bahan kosmetik, pupuk organik, dan biofuel (biodiesel, bioetanol, biogas, dan biohidrogen. Studi ini bertujuan untuk menginvestigasi kombinasi ultrafiltrasi (UF – dissolved air flotation (DAF untuk pemekatan mikroalga skala laboratorium. Hasil penelitian menunjukkan bahwa penurunan fluks membran UF secara tajam sebagai akibat dari deposisi sel mikroalga terjadi pada 20 menit pertama proses filtrasi. Backwash pada interval 20 menit selama 10 detik dengan tekanan 1 bar memberikan pengendalian fouling yang efektif dalam nilai kestabilan fluks yang layak. Membran UF yang digunakan dapat memberikan selektivitas pemisahan biomassa mikroalga ~ 100%. Kualitas permeat sangat stabil, yaitu kekeruhan < 0,5 NTU, kandungan organik < 10 mg/L, dan warna < 10 PCU. Lebih lanjut, pemekatan retentat membran dengan DAF pada tekanan saturasi 6 bar dapat menghasilkan pasta mikroalga dengan konsentrasi 20 g/L. Koagulan PAC perlu ditambahkan kedalam umpan DAF dengan dosis 1,3–1,6 mg PAC/mg padatan tersuspensi.   Kata Kunci: ultrafiltrasi; dissolved air flotation; pemanenan mikroalga; pemekatan mikroalga   Abstract COMBINATION OF Ultrafiltration and Dissolved Air Flotation for Microalgae CONCENTRATION. Microalgae is a prokaryotic photosynthetic microorganism or eukaryotic microorganism  that proliferate rapidly. Cultivation of the microalgae is not only oriented  as natural food for aquacultures, but also developed  for animal food, color pigment, pharmaceutical raw material (β-carotene, antibiotic, fatty acid omega-3, cosmetic raw material, organic fertilizer, and biofuels (biodiesel, bioethanol, biogas, and biohydrogen. This

  5. The kinetics of fossil resin extraction from a flotation concentrate

    Energy Technology Data Exchange (ETDEWEB)

    Li, L.; Yu, Q.; Miller, J.D. [Univ. of Utah, Salt Lake City, UT (United States)

    1995-11-01

    The kinetics of fossil resin extraction from a flotation concentrate by heptane were investigated as a function of process variables using monosize particles. Experimental results provide for a better understanding of the refining process and the basis for subsequent design and construction of a continuous resin refining circuit. Based on the effect of process variables (particle size, stirring speed, and temperature) the resin extraction rate appears to be controlled by surface solvation phenomena. The initial extraction rate was found to be inversely proportional to the initial particle size and a kinetic model is being developed to describe the experimental results.

  6. 细粒矿物浮选技术和高效浮选柱研究进展%Study Status of Flotation Technology and High Effective Flotation Columns for Fine Mineral

    Institute of Scientific and Technical Information of China (English)

    赵培培; 曹亦俊

    2011-01-01

    On the basis of analyzing the property of fine mineral flotation, some flotation technologies for fine mineral which are used widely in recent years are briefly described, such as, carrier flotation, agglomerate flotation, biological flotation , comprehensive force-field flotation etc; and three kinds of high effective flotation columns for fine mineral, Jameson flotation column, packed flotation column, and cyclonic-static microbubble flotation column, are introduced. Finally, the future study direction of flotation technology for fine mineral is prospected.%在分析细粒矿物浮选特性的基础上,综述了载体浮选、絮凝浮选、生物浮选、综合力场浮选等近年来应用广泛的新型细粒矿物浮选技术,并介绍了Jameson浮选柱、充填式浮选柱、旋流-静态微泡浮选柱这3种高效细粒矿物浮选柱,最后对细粒矿物浮选技术今后的研究方向进行了展望.

  7. Composition and flotation performance of plant acidic oil%几种植物油脂酸化油的组成及其浮选性能

    Institute of Scientific and Technical Information of China (English)

    罗惠华; 李成秀; 汤家焰; 王亚运; 陈炳炎

    2012-01-01

    为了研究棉油、大豆油、蓖麻油、玉米油等几种植物酸化油在温度20℃下的浮选性能,采用气相色谱法分析了其脂肪酸的组成,通过浮选试验评价了其性能.结果表明,这几种植物酸化油中,含有脂肪酸的组成不同,大豆与玉米酸化油的不饱和脂肪酸亚油酸,亚麻酸含量较高,而棉油酸化油主要含有油酸与亚油酸、无亚麻酸,蓖麻油主要是羟基油酸.不同植物酸化油捕收剂的浮选性能不同,它们的浮选性能低于油酸.这几种植物酸化油捕收能力是棉油酸化油>大豆酸化油>蓖麻酸化油>玉米酸化油;而大豆酸化油与玉米酸化油捕收剂的选择性相当,但高于棉籽油酸化油和蓖麻油酸化油.因此,作为捕收剂应选用不饱和脂肪酸特别是亚油酸和亚麻酸的含量高的酸化油,有利于胶磷矿的浮选.%The froth flotation tests were conducted to study the flotation performance of acidified vegetable oil such as cottonseed acidic oil, soybean acidic oil, castor acidic oil and corn acidic oil, at the 20℃. And its fatty acid composition was determined by gas chromatography. The results show that the composition of fatty acid in this several acidified vegetable oil is different, soybean acidic oil and corn acidic oil rich in unsaturated fatty acids with high linoleic acid and linolenic acid contents, while cottonseed acidic oil mainly contains oleic acid and linoleic acid, no linolenic acid and castor oil main ingredients for hydroxyl acid. The floatability of this several acidified vegetable oil is also different which is weaker than oleic acid. In unit of acidified vegetable oil, the collection capacity of cottonseed acidic oil is better than soybean acidic oil, castor acidic oil and corn acidic oil, while the selective of soybean acidic oil which is equal to corn acidic oil is better than cottonseed acidic oil and castor acidic oil. So, it is better for the flotation of collophanite as the

  8. Copper bioleaching from after-flotation waste using microfungi

    Directory of Open Access Journals (Sweden)

    Ewelina Kasińska-Pilut

    2005-11-01

    Full Text Available The aim of the research presented is an analysis of ways of utilizing microfloral autochthonous organisms from the after-flotation waste of the Gilow stockpile in order to bioleach copper. The alkaline character of the environment disables the use of the traditional processes of acid bioleaching, because of both the economical and environmental aspects. A research of the bioleaching process of the after-flotation waste was conducted using microfungi of the Aspergillus niger species, which dominate in the autochthonous environment. The metabolism of these microfungi, connected with the production of large amounts of organic acids, allowed to conceptualize their usage in the biohydrometalurgy copper processes. After isolating in a pure culture and multiplying the microfungal biomass Aspergillus niger, the experiments began. Weighed samples of the waste were covered with a selective medium and then inoculated with the microfungal biomass, playing the role of the bioleaching agent. After thirty days of incubation, the end product was chemically analyzed, showing effects of the conducted copper bioleaching process (81,23–87,98 %.

  9. Application of dissolved air flotation on separation of waste plastics ABS and PS.

    Science.gov (United States)

    Wang, Hui; Chen, Xiao-Lei; Bai, Yang; Guo, Chao; Zhang, Li

    2012-07-01

    The aim of this research was to separate waste plastics acrylonitrile butadiene styrene (ABS) and polystyrene (PS) by dissolved air flotation in a self-designed dissolved air flotation apparatus. The effects of wetting agents, frother, conditioning time and flotation time on flotation behavior of waste plastics ABS (w-ABS) and PS (w-PS) were investigated and the optimized separation conditions were obtained. The results showed that when using 25 mgL(-1) tannic acid, 5 mgL(-1) terpineol, 15 min conditioning time and 15 min flotation time, mixtures of w-ABS and w-PS were separated successfully by dissolved air flotation in two stages, the results revealed that the purity and recovery rate of w-PS in the floated products were 90.12% and 97.45%, respectively, and the purity and recovery rate of w-ABS in the depressed products were 97.24% and 89.38%, respectively. Based on the studies of wetting mechanism of plastic flotation, it is found that the electrostatic force and hydrophobic attraction cannot be the main factor of the interaction between wetting agent molecules and plastic particles, which can be completed through water molecules as a mesophase, and a hydrogen bonding adsorption model with hydration shell as a mesophase was proposed.

  10. Leaching behaviour and mechanical properties of copper flotation waste in stabilized/solidified products.

    Science.gov (United States)

    Mesci, Başak; Coruh, Semra; Ergun, Osman Nuri

    2009-02-01

    This research describes the investigation of a cement-based solidification/stabilization process for the safe disposal of copper flotation waste and the effect on cement properties of the addition of copper flotation waste (CW) and clinoptilolite (C). In addition to the reference mixture, 17 different mixtures were prepared using different proportions of CW and C. Physical properties such as setting time, specific surface area and compressive strength were determined and compared to a reference mixture and Turkish standards (TS). Different mixtures with the copper flotation waste portion ranging from 2.5 to 12.5% by weight of the mixture were tested for copper leachability. The results show that as cement replacement materials especially clinoptilolite had clear effects on the mechanical properties. Substitution of 5% copper flotation waste for Portland cement gave a similar strength performance to the reference mixture. Higher copper flotation waste addition such as 12.5% replacement yielded lower strength values. As a result, copper flotation waste and clinoptilolite can be used as cementitious materials, and copper flotation waste also can be safely stabilized/solidified in a cement-based solidification/stabilization system.

  11. Recovery of fine coal from waste streams using advanced column flotation

    Energy Technology Data Exchange (ETDEWEB)

    Groppo, J.G.; Parekh, B.K. (Kentucky Univ., Lexington, KY (United States). Center for Applied Energy Research)

    1991-01-01

    The overall objective of this program is to evaluate the application of an advanced physical separation technique, namely Ken-Flote'' column flotation to recover clean coal with minimum sulfur and ash content at greater than 90 percent combustible recovery from two Illinois coal preparation plant fine waste streams. The project will optimize various operating parameters with particular emphasis on fine bubble generating devices and reagent packages to enhance the rejection of liberated ash and pyritic sulfur. During this contract period, column flotation testing was completed on the flotation feed slurry obtained from the Kerr-McGee Galatia Preparation Plant. The column flotation tests were conducted using three different bubble generating devices: Static, gas saver and foam jet spargers. Each of these devices was tested with three different frothers and various column operating variables to provide maximum combustible recovery, minimum product ash and maximum pyrite rejection. In general, the column flotation provided a clean coal containing about 4--6 percent ash at combustible recovery ranging from 88 to 92 percent while pyrite rejection was 70 to 75 percent. Flotation tests were also conducted on a slurry sample obtained from The Ziegler {number sign}26 Preparation Plant in Sesse, Illinois. Base-line flotation testing was completed using batch flotation to identify optimum reagent addition. Column flotation of the Ziegler slurry provided a clean coal containing 4--6 percent ash with a combustible recovery of 90--95 percent and pyrite rejection of 60--67 percent. Efforts are in progress in installing a 6-inc. I.D. pilot column at the Ziegler {number sign}26. 9 figs.

  12. Nature of (001) and (001) faces and flocculation flotation of kaolinite

    Institute of Scientific and Technical Information of China (English)

    孙伟; 王毓华; 李海普; 胡岳华

    2003-01-01

    Flotation mechanism of kaolinite was investigated through flotation test, SEM analysis and quantum chemical simulation calculation. It is shown that the (001) face of kaolinite easily adsorb cationic collector to exhibit hydrophobicity; the (001) face is easily interacted with the reagent carrying the group of high electronegativity (-O-,-N-, F-) to show hydrophilicity. The cationic and anionic polyacrylamide are adsorbed onto the (001) face of kaolinite and the flocculation of kaolinite particles may take place; the (001) faces are exposed to interact with cationic collector to be rendered hydrophobicity. Thus, the macromolecules can evidently enhance the flotation of kaolinite in alkaline media.

  13. Effect of hydroxamic acid starch on reverse flotation desilicate from diasporic bauxite

    Institute of Scientific and Technical Information of China (English)

    胡岳华; 李海普; 蒋玉仁

    2002-01-01

    It is important to depress diaspore effectively in order to remove silicates from diasporic bauxite. A new water soluble polymer hydroxamic acid starch (HA-starch) was prepared. The effects of the product on the diaspore and kaolinite flotation were investigated and its reactive mechanism was studied by zeta potential measurement and FTIR. The results show that HA-starch can depress diaspore while make positive effect on kaolinite flotation at low pH value(pH below 6). The flotation recovery of diaspore was sharply decreased with the increase of concentration of HA-starch. The chemical adsorption of HA-starch on the surface of diaspore was revealed.

  14. Adsorption of Crystal Violet on Activated Carbon Prepared from Coal Flotation Concentrate

    Science.gov (United States)

    Aydogmus, Ramazan; Depci, Tolga; Sarikaya, Musa; Riza Kul, Ali; Onal, Yunus

    2016-10-01

    The objective of this study is firstly to investigate the floatability properties of Zilan- Van coal after microwave irradiation and secondly to produce activated carbon from flotation concentrate in order to remove Crystal Violet (CV) from waste water. The flotation experiments showed that microwave heating at 0.9 kW power level for 60 sec exposure time enhanced the hydrophobicity and increased the flotation yield. The activated carbon with remarkable surface area (696 m2/g) was produced from the flotation concentrate and used to adsorb CV from aqueous solution in a batch reactor at different temperature. The adsorption properties of CV onto the activated carbon are discussed in terms of the adsorption isotherms (Langmuir and Freundlich) and found that the experimental results best fitted by the Langmuir model.

  15. Influence of a High-Pressure Comminution Technology on Concentrate Yields in Copper Ore Flotation Processes

    Directory of Open Access Journals (Sweden)

    Saramak D.

    2014-10-01

    Full Text Available The article concerns the issues of flotation process effectiveness in relationship to the operating conditions of a high-pressure comminution process course. Experimental programme covering a flotation laboratory batch tests was a verification technique of a high-pressure crushing operations course. The most favorable values of flotation concentrate weight recoveries were obtained for the pressing force 6 kN and 4% of the feed moisture. It was also determined the model of the concentrate weight recovery as a function of pressing force in the press and feed moisture content. This model was the basis for the optimization of effects of copper ore flotation processes preceded in high-pressure crushing operation in roller presses.

  16. Statistical Evaluation and Optimization of Factors Affecting the Leaching Performance of Copper Flotation Waste

    Directory of Open Access Journals (Sweden)

    Semra Çoruh

    2012-01-01

    Full Text Available Copper flotation waste is an industrial by-product material produced from the process of manufacturing copper. The main concern with respect to landfilling of copper flotation waste is the release of elements (e.g., salts and heavy metals when in contact with water, that is, leaching. Copper flotation waste generally contains a significant amount of Cu together with trace elements of other toxic metals, such as Zn, Co, and Pb. The release of heavy metals into the environment has resulted in a number of environmental problems. The aim of this study is to investigate the leaching characteristics of copper flotation waste by use of the Box-Behnken experimental design approach. In order to obtain the optimized condition of leachability, a second-order model was examined. The best leaching conditions achieved were as follows: pH = 9, stirring time = 5 min, and temperature = 41.5°C.

  17. Statistical evaluation and optimization of factors affecting the leaching performance of copper flotation waste.

    Science.gov (United States)

    Coruh, Semra; Elevli, Sermin; Geyikçi, Feza

    2012-01-01

    Copper flotation waste is an industrial by-product material produced from the process of manufacturing copper. The main concern with respect to landfilling of copper flotation waste is the release of elements (e.g., salts and heavy metals) when in contact with water, that is, leaching. Copper flotation waste generally contains a significant amount of Cu together with trace elements of other toxic metals, such as Zn, Co, and Pb. The release of heavy metals into the environment has resulted in a number of environmental problems. The aim of this study is to investigate the leaching characteristics of copper flotation waste by use of the Box-Behnken experimental design approach. In order to obtain the optimized condition of leachability, a second-order model was examined. The best leaching conditions achieved were as follows: pH = 9, stirring time = 5 min, and temperature = 41.5 °C.

  18. The Effect of Polystyrene on the Carrier Flotation of Fine Smithsonite

    Directory of Open Access Journals (Sweden)

    Xiangfeng Zhang

    2017-03-01

    Full Text Available Carrier flotation is a common technique used to improve flotation recovery of ultrafine ores. In this study, we used coarse polystyrene as the carrier material to enhance flotation recovery of fine smithsonite (ZnCO3 particles. Sodium oleate was used as the collector and played a role in the adhesion of fine smithsonite to polystyrene due to its amphipathic properties. The carrier feature of polystyrene was demonstrated using particle size analysis, total organic carbon, and scanning electron microscopy. The fine smithsonite particles coated the polystyrene particles through a reaction between the active zinc sites and the carboxyl head groups of the oleate adsorbed on smithsonite and through a hydrophobic interaction between polystyrene and the hydrocarbon chains of the oleate. Newly enlarged particle aggregates with smithsonite shells enhanced collision and attachment of the hydrophobized aggregates with bubbles, which accelerated smithsonite flotation recovery.

  19. Flotation of indium-beard marmatite from multi-metallic ore

    Institute of Scientific and Technical Information of China (English)

    TONG Xiong; SONG Shaoxian; HE Jian; Alejandro Lopez-Valdivieso

    2008-01-01

    Flotation of indium-beard marmatite from Dulong multi-metallic ore in Yunnan Province of China was studied to improve the grades and recoveries of zinc and indium of the zinc concentrate in Dulong concentration plant.The experimental results indicated that copper sulfate mixed with a chemical reagent X-1 as the activator in the marmatite flotation produced a much better beneficiation than copper sulfate alone,increasing the zinc and indium recoveries of 10% and 6%,respectively,while the concentrate grades remained unchanged.Also,the new activator acted well around pH 10,allowing large savings on lime consumption in the rnarmatite flotation.In addition,it has been found that a sufficient activated lime of activator with ore slurry in the flotation is needed to achieve good beneficiation of the marmatite ore.

  20. The effect of quartz on the flotation of pyrite depressed by serpentine

    Directory of Open Access Journals (Sweden)

    Bo Feng

    2015-01-01

    Full Text Available The effect of quartz particles on the flotation of pyrite depressed by serpentine has been investigated through flotation tests, adsorption tests, zeta potential measurements and DLVO calculation. The results show that the presence of hydrophilic serpentine slimes on pyrite surface reduces collector adsorption and results in lower recovery of pyrite. The finer the serpentine slime is, the lower the pyrite recovery will be. Quartz particles do not interfere with pyrite flotation. However, the addition of quartz particles increases the adsorption of collector on pyrite surface and limits the detrimental effect of serpentine on pyrite flotation. The fine-grained quartz is more effective. Zeta potential measurements and DLVO calculation illustrate that the zeta potential of quartz is more negative than that of pyrite and the attraction force between serpentine and quartz is stronger than force between serpentine and pyrite, thus some serpentine slimes were transferred from pyrite surface to quartz in the process of attrition.

  1. Pilot scale direct flotation of a phosphate ore with silicate-carbonate gangue.

    OpenAIRE

    2012-01-01

    The present pilot scale study addresses the direct flotation route for the concentration of a phosphate ore bearing a silicate-carbonate gangue. The target was to selectively separate apatite from a phosphate ore bearing silicate/carbonate gangue using flotation columns. Based on the results of a previous laboratory scale investigation, a reagents scheme was selected and tested, using, under alkaline conditions, corn starch and a natural collector extracted from the distillation of coconut oi...

  2. Major elements distribution during liquefaction of beneficated coal fractions from hydrocyclone and flotation

    Energy Technology Data Exchange (ETDEWEB)

    Barraza, J. [Universitaria Melendez (Colombia). Dept. de Procesos Quimicos; Cloke, M.; Belghazi, A. [Nottingham Univ. (United Kingdom). Dept. of Chemical Engineering

    1997-12-31

    Beneficiated coal fractions obtained by hydrocyclone and column flotation separation were liquefied in order to determine their effect on the reduction of the major element content in the coal extract liquid prior to hydroprocessing. Results showed that some major elements, mainly Ca, Mn and Ti, were reduced using these beneficiated coal fractions. In general, all the elements exhibit higher reduction using overflow from the cyclone separation compared to the concentrate from the column flotation. (orig.)

  3. A honeycomb-tube packing medium and its application to column flotation

    Institute of Scientific and Technical Information of China (English)

    ZHANG Min; SHI Chang-sheng; LIU Jiong-tian; ZHAI Ai-feng

    2009-01-01

    We address problems in the development of large-scale flotation columns that use short cylinders. As a starting point, we investigated the packing medium to identify a highly efficient internal packing for the flotation column. The chosen packing was a honeycomb structure with an aperture diameter of 80 mm, a web thickness of 0.80 mm, a film height of 1000 mm, packed into a 400 mm diameter space, which completely filled the vessel at optimal cost. The column consisted of a modular ring of single-hole hexagonal honeycomb tube packing made from atactic polyproplene (PP-R). The packing was tested in a cyclonic, static mi-cro-bubble flotation column. Computational fluid dynamic modeling was used to analyze the flotation fluid in a honeycomb tube packed flotation column. Our results show that the fluid axial movement was maximized and that the transverse fluid velocities were zero in the vicinity of axial flow. Using the honeycomb tube packing for copper sulfide flotation we observed that the average concentration in the product was increased to 25.41%, from an average feed concentration of 0.729%, with an average recovery of 92.92%. The demands of on-site industrial production were met.

  4. Kinetics of ion flotation of Co(II)-EDTA complexes from aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Soliman, Mohamed A. [Atomic Energy Authority, Cairo (Egypt). Egypt Second Research Reactor; Rashad, Ghada M.; Mahmoud, Mamdoh R. [Atomic Energy Authority, Cairo (Egypt). Nuclear Chemistry Dept.

    2015-07-01

    The flotation kinetics of Co(II)-EDTA complexes from aqueous solutions using cetylpyridinium chloride (CPyCl) is studied and discussed in the present work. The effects of many variables on the ultimate recovery and the flotation rate are investigated. The data obtained from solutions of different pH values showed that Co(II)-EDTA complexes are successfully floated at pH 7.8. While at pH 3.4 and 11.2, both the ultimate recovery and the flotation rate are dependent on the concentration of CPyCl. Flotation of Co(II)-EDTA at different air flow rates, CPyCl concentrations and ionic strength showed that the ultimate recovery and the flotation rate are markedly affected. The other parameters (cobalt, EDTA and ethanol concentrations) had no effect on the ultimate recovery, while significantly affected the flotation rate. At the optimum conditions (Co(II):EDTA = 1:1; CPyCl:Co(II) = 4:1; pH7.8; G = 25 cm{sup 3}/min), removals more than 99% are achieved for radiocobalt. The classical first-order and the second-order kinetic models are used throughout the work to analyze the experimental kinetic data. At all the studied parameters, the kinetic data of Co(II)-EDTA complexes are better fitted to the classical first-order model.

  5. Removal of Cadmium (II from Simulated Wastewater by Ion Flotation Technique

    Directory of Open Access Journals (Sweden)

    Mohammad Taghi Ghaneian

    2013-02-01

    Full Text Available A separation technique which has recently received a sharp increase in research activities is “ion flotation”. This technique has four important advantages for treating wastewaters: low energy consumption, small space requirements, small volume of sludge and acting selectively. The present study aims to optimize parameters of ion flotation for cadmium removal in simulated wastewater at laboratory scale. It was obtained on the reaction between Cd2+ and sodium dodecylesulfate (SDS collector followed by flotation with ethanol as frother. Test solution was prepared by combining the required amount of cadmium ion, SDS and necessary frother or sodium sulfate solution. All experiments were carried out in a flotation column at laboratory temperature (27°C, adjusted pH = 4 and 120 minutes. The different parameters (namely: flow rate, cadmium, SDS and frother concentrations and ionic strength influencing the flotation process were examined. The best removal efficiency obtained at a collector-metal ratio of 3:1 in 60 min with flow rate of 150 mL/min was 84%. The maximum cadmium removal was 92.1% where ethanol was introduced at a concentration 0.4% to flotation column with above conditions. The obtained results were promising, as both cadmium and collector were effectively removed from wastewater. Hence, the application of ion flotation for metal ions removal from effluents seems to be efficient.

  6. Flotation separation of polyvinyl chloride and polyethylene terephthalate plastics combined with surface modification for recycling.

    Science.gov (United States)

    Wang, Chongqing; Wang, Hui; Fu, Jiangang; Zhang, Lingling; Luo, Chengcheng; Liu, Younian

    2015-11-01

    Surface modification with potassium permanganate (KMnO4) solution was developed for separation of polyvinyl chloride (PVC) and polyethylene terephthalate (PET) waste plastics. The floatability of PVC decreases with increasing of KMnO4 concentration, treatment time, temperature and stirring rate, while that of PET is unaffected. Fourier transform infrared (FT-IR) analysis confirms that mechanism of surface modification may be due to oxidization reactions occurred on PVC surface. The optimum conditions are KMnO4 concentration 1.25 mM/L, treatment time 50 min, temperature 60°C, stirring rate 300 r/min, frother concentration 17.5 g/L and flotation time 1 min. PVC and PET with different particle sizes were separated efficiently through two-stage flotation. Additionally, after ultrasonic assisted surface modification, separation of PVC and PET with different mass ratios was obtained efficiently through one-stage flotation. The purity and the recovery of the obtained products after flotation separation are up to 99.30% and 99.73%, respectively. A flotation process was designed for flotation separation of PVC and PET plastics combined with surface modification. This study provides technical insights into physical separation of plastic wastes for recycling industry.

  7. Characteristic of flotation deinking using bio and synthetic surfactant at different air flow rate

    Science.gov (United States)

    Trismawati, Wardana, I. N. G.; Hamidi, Nurkholis; Sasongko, Mega Nur

    2016-03-01

    Flotation deinking has industrially applied but several problems keep unsolved because limitations have to compete with several variables present. Flotation deinking is multi variables process, so studying flotation deinking is still interesting. In this research, the amount of variables was reduced and focused to the performance comparison between flotation deinking of old newspaper (ONP) using biodegradable fatty acid of morinda citrifolia as the raw bio surfactant (RBS) and biodegradable fatty acid of palm oil that had been converted to be commercial surfactant (CS). The flotation was done at laboratory flotation cell equipped with orifice at different diameter (orifice number 20, 40 and 60) with adjustable airflow rate. Brightness and Effective Residual Ink Concentration (ERIC) of the deinked pulp were measured. The best results were achieved on orifice number 40 with the highest brightness of 41.96 °ISO and 40.96 °ISO when using CS and RBS respectively, and lowest ERIC of 896.82 ppm and 1001.72 ppm when using CS and RBS respectively. The percentage delta of deinking power characteristic between CS and RBS was 2.36% and 11.70% for brightness and ERIC, respectively.

  8. Ammonia modification for flotation separation of polycarbonate and polystyrene waste plastics.

    Science.gov (United States)

    Wang, Chong-qing; Wang, Hui; Gu, Guo-hua; Lin, Qing-quan; Zhang, Ling-ling; Huang, Luo-luo; Zhao, Jun-yao

    2016-05-01

    A promising method, ammonia modification, was developed for flotation separation of polycarbonate (PC) and polystyrene (PS) waste plastics. Ammonia modification has little effect on flotation behavior of PS, while it changes significantly that of PC. The PC recovery in the floated product drops from 100% to 3.17% when modification time is 13min and then rises to 100% after longer modification. The mechanism of ammonia modification was studied by contact angle, and Fourier transform infrared (FT-IR) and X-ray photoelectron spectroscopy (XPS) measurements. Contact angle of PC indicates the decline of PC recovery in the floated product is ascribed to an increase in surface wettability. FT-IR and XPS spectra suggest that ammonia modification causes chemical reactions occurred on PC surface. Flotation behavior of ammonia-modified PC and PS was investigated with respect to flotation time, frother concentration and particle sizes. Flotation separation of PC and PS waste plastics was conducted based on the flotation behavior of single plastic. PC and PS mixtures with different particle sizes are separated efficiently, implying that the technology possesses superior applicability to particle sizes of plastics. The purity of PS and PC is up to 99.53% and 98.21%, respectively, and the recovery of PS and PC is larger than 92.06%. A reliable, cheap and effective process is proposed for separation of PC and PS waste plastics.

  9. The critical importance of pulp concentration on the flotation of galena from a low grade lead–zinc ore

    Directory of Open Access Journals (Sweden)

    Xianping Luo

    2016-04-01

    Full Text Available The Qixia orebody is a complex lead–zinc sulfide system with pyrite gangue and minor amounts of copper. In order to improve the flotation results, laboratory scale flotation testing of ore samples taken from this operation was performed. Flotation tests used a sequential recovery protocol for selective flotation of first the lead and thereafter the zinc. The key parameters that influence flotation performance of lead mineral were tested in this paper. The test data show that, for comparable collector, grinding time, flotation pH and solid-in-pulp concentration, the increase of solid-in-pulp concentration has the most significant effect on the recovery and selective separation of lead mineral. The increase of solid-in-pulp concentration from 27% to 55% makes the recovery of lead mineral increased from 60% to 80% and the lead grade increased from 27.5% to 29.1%.

  10. Process mineralogy of copper-nickel sulphide flotation by cyclonic-static micro-bubble flotation column

    Institute of Scientific and Technical Information of China (English)

    CAO Yi-jun; GUI Xia-hui; MA Zi-long; YU Xiao-xia; CHEN Xiao-dong; ZHANG Xiu-pin

    2009-01-01

    In our study we investigated a refractory copper-nickel sulfide ore separation by using a cyclonic-static micro-bubble flotation column (FCSMC). The process mineralogy of the main products was studied. Using a scanning electron micro-scope-energy dispersive system (SEM-EDS) and an X-ray spectrometer the mineral category and content of samples were analyzed. By using a mineral liberation analyzer (MLA) the mineral liberation characteristics were revealed. It is shown that in roughing feed the monomers liberation degree of nickel pyrite and chalcopyrite take up 84.11% and 88.82%, respectively. In tailings, the lost nickel pyrite and chalcopyrite are mainly monomers. Therefore, strengthening the micro-fine particle recovery capacity is the key to increase recovery.

  11. 充填浮选柱正-反浮选胶磷矿工艺研究%Study on phosphate rock flotation with packed flotation column

    Institute of Scientific and Technical Information of China (English)

    任慧; 丁一刚; 吴元欣; 李定或

    2001-01-01

    通过充填浮选柱浮选胶磷矿的工艺实验,提出了串联操作的正-反浮选流程,得到了较为合适的工艺条件,为生产放大提供了理论依据。%According to the process experiment of using packed flotation column to float phosphate rock, a positive-reversed flotation circuit was put forward, suitable technological conditions of the circuit was obtained, and a theoretic basis was supplied for the commercial production of the circuit.

  12. Technological investigations of sulphide oxidation from flotation tailings in order to increase the degree of copper leaching

    OpenAIRE

    Jonović, Radojka; Avramović, Ljiljana; Stevanović, Zoran; Jonović, Marko

    2014-01-01

    The off-balance resources present the environmental problem and potential resource for copper extraction. This paper presents the results obtained using different reagents for the process of sulphide form oxidation of copper from flotation tailings. For the investigation in this paper work, the samples of flotation tailings were taken from the Old Flotation Tailing Dump of the Mining and Smelting Complex Bor in Eastern Serbia. Experimental testing was carried out in order to increase the leac...

  13. 低品位石墨矿晶体保护选矿工艺研究%Research on Crystal Protection and Flotation of Low-grade Graphite Ore

    Institute of Scientific and Technical Information of China (English)

    孙政元; 曾钦; 李根兴; 田优杰

    2012-01-01

    Using conventional flotation method, this article used the process of multi - stage grinding and multiple separation to protect crystal and separate minerals. This test considered the grinding fineness, the dosage of sodium silicate, the dosage of kerosene in flotation. Closed circuit test output good technical indicators and the qualified graphite concentrate.%运用常规浮选法,采用多段磨矿、多次选别工艺对某低品位石墨矿进行选矿及晶体保护试验研究.试验考察了磨矿细度、水玻璃用量、煤油用量对浮选的影响.经闭路试验获得了较好的技术指标,石墨精矿品位为85.78%,回收率82.72%.

  14. Re-flotation of black coal slurries from settling pit of František Mine, OKD, Inc.

    Directory of Open Access Journals (Sweden)

    Feèko Peter

    1998-09-01

    Full Text Available The possibility of re-flotation of black-coal slurries from slurry ponds of Mine František, OKD, a.s was tested and is presented in the paper. Two types of collectors, namely Montanol and Flotacol NX, and bioflocculants such as been yeast were used and bioflocculants as is beer yeast to the quality of flotation concentrates was observed The results of work shows, that influence of bioflocculants in re-flotation of black-coal slurries is significant. The marked increase of flotation concentrate mass yields were signed in maintenance of required quality of black coal concentrates.

  15. Accuracy of egg flotation throughout incubation to determine embryo age and incubation day in waterbird nests

    Science.gov (United States)

    Ackerman, Joshua T.; Eagles-Smith, Collin A.

    2010-01-01

    Floating bird eggs to estimate their age is a widely used technique, but few studies have examined its accuracy throughout incubation. We assessed egg flotation for estimating hatch date, day of incubation, and the embryo's developmental age in eggs of the American Avocet (Recurvirostra americana), Black-necked Stilt (Himantopus mexicanus), and Forster's Tern (Sterna forsteri). Predicted hatch dates based on egg flotation during our first visit to a nest were highly correlated with actual hatch dates (r = 0.99) and accurate within 2.3 ± 1.7 (SD) days. Age estimates based on flotation were correlated with both day of incubation (r = 0.96) and the embryo's developmental age (r = 0.86) and accurate within 1.3 ± 1.6 days and 1.9 ± 1.6 days, respectively. However, the technique's accuracy varied substantially throughout incubation. Flotation overestimated the embryo's developmental age between 3 and 9 days, underestimated age between 12 and 21 days, and was most accurate between 0 and 3 days and 9 and 12 days. Age estimates based on egg flotation were generally accurate within 3 days until day 15 but later in incubation were biased progressively lower. Egg flotation was inaccurate and overestimated embryo age in abandoned nests (mean error: 7.5 ± 6.0 days). The embryo's developmental age and day of incubation were highly correlated (r = 0.94), differed by 2.1 ± 1.6 days, and resulted in similar assessments of the egg-flotation technique. Floating every egg in the clutch and refloating eggs at subsequent visits to a nest can refine age estimates.

  16. Comparison of passive fecal flotation run by veterinary students to zinc-sulfate centrifugation flotation run in a diagnostic parasitology laboratory.

    Science.gov (United States)

    Gates, Maureen C; Nolan, Thomas J

    2009-10-01

    The sensitivity of fecal examination methods can be influenced by both technician error and methodology. In this analysis, we compared the results of 335 passive fecal flotation examinations performed on the feces of stray dogs by 3rd-yr veterinary students at the University of Pennsylvania, School of Veterinary Medicine, to the results obtained through zinc-sulfate centrifugation performed by the diagnostic parasitology laboratory on the same fecal samples. The students' passive flotation results agreed with the laboratory zinc-sulfate centrifugation for only 62.4% of samples. Students were able to diagnose 75.0% of Ancylostoma caninum cases, 71.4% of Toxocara canis cases, 54.2% of Trichuris vulpis cases, 26.7% of Cystoisospora spp. (C. ohioensis-like and C. canis) cases, and 14.7% of Giardia lamblia cases. There were also 70 instances where students reported the presence of parasites in the sample that were not diagnosed by zinc-sulfate centrifugation. Based on the overall study findings, passive fecal flotation examinations run in private practice could be missing up to 50.5% of infected dogs, due to either technician error or inherent limitations to the passive fecal flotation technique.

  17. 载体浮选回收某锌浸出渣中的银%Recovering Silver from Zinc Leaching Residue with Carder Flotation

    Institute of Scientific and Technical Information of China (English)

    葛英勇; 石美佳; 曾李明

    2012-01-01

    In order to recover silver from zinc leaching residue which produced by a zinc hydrometallurgy factory in Inner Mongolia, did some tests with flotation method. The results show that, because of the fine disseminated silver mineral in zinc leaching residue, the recovery rate is low with conventional flotation but can be remarkably better by carrier flotation. Taking -0. 037 mm organic matter AC-0 as carrier, lime for pH adjustment agent, odium sulfide as activating agent, ammonium dibuyldithiophosphate and isopropyl ethylthionocarbamate as collectors, finally get the grade of 8 670 g/t silver concentrate with the recovery rate of 61. 67% through the closed circuit test of one roughing, one cleaning, and one scavenging system.%为使内蒙古某湿法炼锌厂锌浸出渣中的银得到回收,对该锌浸出渣进行了浮选试验.试验结果表明,由于银矿物主要以微细粒分布在锌浸出渣中,导致常规浮选回收率低下,而采用载体浮选工艺可显著改善浮银效果:以粒度为-0.037 mm的有机物AC -0为载体、石灰为pH调整剂、硫化钠为活化剂、丁铵黑药和乙硫氨酯为捕收剂,通过1粗1精1扫闭路载体浮选流程,可获得银品位为8 670 g/t、银回收率为61.67%的银精矿.

  18. Flotation technology of refractory low-grade molybdenum ore

    Institute of Scientific and Technical Information of China (English)

    Du Shuhua; Luo Zhenfu

    2013-01-01

    Because of the low grade,high oxidation rate and the accumulation of little associated metal sulfide ore in the molybdenum concentrate during flotation,the Qingyang molybdenum ore is difficult to beneflciate.The experimental studies of grinding fineness,the amount of roughing modifier,depressant and collector were completed.In the cleaning process,the contrast experiments of one regrinding.the regrinding and scrubbing,two-stage regrinding was carried.The result shows that the grade of molybdenum ore concentrate is 45.31%,the recovery is 65.98% and the rich ore ratio reaches 20.59% by the regrinding and scrubbing seven cleaning,the regrinding of concentrations from middling of molybdenum-sulfur separation.The regularly-concentrated material from the apparatus was as the middling products.Hence,ideal beneficiation index can be obtained with a rational mineral processing,which offers new beneficiating technology for the refractory low-grade molybdenum ore in China.

  19. Electro-coagulation-flotation process for algae removal.

    Science.gov (United States)

    Gao, Shanshan; Yang, Jixian; Tian, Jiayu; Ma, Fang; Tu, Gang; Du, Maoan

    2010-05-15

    Algae in surface water have been a long-term issue all over the world, due to their adverse influence on drinking water treatment process as well as drinking water quality. The algae removal by electro-coagulation-flotation (ECF) technology was investigated in this paper. The results indicated that aluminum was an excellent electrode material for algae removal as compared with iron. The optimal parameters determined were: current density=1 mA/cm(2), pH=4-7, water temperature=18-36 degrees C, algae density=0.55 x 10(9)-1.55 x 10(9) cells/L. Under the optimal conditions, 100% of algae removal was achieved with the energy consumption as low as 0.4 kWh/m(3). The ECF performed well in acid and neutral conditions. At low initial pH of 4-7, the cell density of algae was effectively removed in the ECF, mainly through the charge neutralization mechanism; while the algae removal worsened when the pH increased (7-10), and the main mechanism shifted to sweeping flocculation and enmeshment. The mechanisms for algae removal at different pH were also confirmed by atomic force microscopy (AFM) analysis. Furthermore, initial cell density and water temperature could also influence the algae removal. Overall, the results indicated that the ECF technology was effective for algae removal, from both the technical and economical points of view.

  20. Production of brown and black pigments by using flotation waste from copper slag.

    Science.gov (United States)

    Ozel, Emel; Turan, Servet; Coruh, Semra; Ergun, Osman Nuri

    2006-04-01

    One of the major problems in copper-producing countries is the treatment of the large amount of copper slag or copper flotation waste generated from copper slag which contains significant amounts of heavy metals such as Cu, Zn, Pb and Co. Dumping or disposal of such large quantities of flotation waste from copper slag causes environmental and space problems. In this study, the treatment of flotation waste from copper slag by a thermal method and its use as an iron source in the production of inorganic brown and black pigments that are used in the ceramic industry were investigated. The pigments were produced by calcining different amounts of flotation waste and chromite, Cr2O3, ZnO and CoO mixtures. The pigments obtained were added to transparent ceramic glazes and porcelainized tile bodies. Their colours were defined by L*a*b* measurements with a spectrophotometer. The results showed that flotation waste from copper slag could be used as an iron source to produce brown and black pigments in both ceramic body and glazes.

  1. Recovery of fine coal from waste streams using advanced column flotation

    Energy Technology Data Exchange (ETDEWEB)

    Groppo, J.G.; Parekh, B.K.

    1991-01-01

    The overall objective of this program is to evaluate the application of an advanced physical separation technique, namely Ken-Flote'' column flotation to recover clean coal with minimum sulfur and ash content at greater than 90 percent combustible recovery from two Illinois coal preparation plant fine waste streams. This project will optimize various operating parameters with particular emphasis on fine bubble generating devices and reagent packages to enhance to rejection of liberated ash and pyritic sulfur. During this contract period, column flotation testing was conducted on the flotation feed slurry obtained from the Kerr-McGee Galatia Preparation Plant. The column flotation tests were conducted using three different bubble generating devices: static, gas saver and foam jet spargers. Each of these devices was tested with three different frothers and various column operating variables to provide maximum combustible recovery, minimum product ash and maximum pyrite rejection. In general, the column flotation provided a clean coal containing about 4--6 percent ash at combustible recovery ranging from 88 to 92 percent. 10 figs.

  2. N-(6-(hydroxyamino)-6-oxohexyl) decanamide collector: Flotation performance and adsorption mechanism to diaspore

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Lanqing [College of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); Key Laboratory of Yueyang Chinese Herbal Utilization, Yueyang Vocational Technical College, Yueyang 414000 (China); Wang, Shuai [College of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); Zhong, Hong, E-mail: zhongh@csu.edu.cn [College of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China); Liu, Guangyi, E-mail: guangyiliu@csu.edu.cn [College of Chemistry and Chemical Engineering, Central South University, Changsha 410083 (China)

    2015-08-30

    Graphical abstract: The potential absorption model of NHOD on diaspore surface. - Highlights: • A novel surfactant NHOD was first introduced as diaspore flotation collector. • NHOD exhibited superior collecting power to diaspore against gangue. • NHOD's has double active centers to mineral surfaces and double hydrophobic groups. • NHOD molecules formed intermolecular hydrogen bonds on diaspore surfaces. - Abstract: In this paper, a novel surfactant, N-(6-(hydroxyamino)-6-oxohexyl)decanamide (NHOD) was synthesized and used as a collector for flotation separation of diaspore and aluminosilicate minerals. The adsorption mechanism of NHOD onto diaspore was also investigated by FTIR spectra, zeta potential measurement and XPS. The flotation results demonstrated that NHOD exhibited superior collecting power to diaspore and selectivity against kaolinite and illite and could effectively realize flotation recovery of diaspore from bauxite ores contained aluminosilicate minerals under neutral conditions. The results of XPS, FTIR spectra and zeta potential illustrated that at around pH 7.0, NHOD might chemisorb on diaspore surfaces through Al−O coordination bonds formed by binding its −C(=O)NHOH or −C(=O)NH− chelate groups with aluminum atoms on diaspore surfaces. NHOD's unique properties, such as characteristic bond patterns onto diaspore surfaces, two hydrophobic groups, and intermolecular hydrogen bonds between neighboring NHOD molecules coated on diaspore surfaces, rendered it to be a superior flotation collector for diaspore.

  3. Flotation of a new chelate collector on fine refractory iron ore-containing carbonate

    Institute of Scientific and Technical Information of China (English)

    王婷霞; 朱一民; 桂夏辉

    2016-01-01

    A suitable and efficient flotation collector at normal atmospheric temperature for Donganshan iron ore was developed. A new chelate collector W-2 was synthesized. At 30 °C, condition flotation tests on mixed magnetic concentrate of Donganshan sintering plant established the best reagent system. With the optimum reagent system, one direct flotation and one reverse flotation including one roughing, one cleaning and two scavenging stages have been conducted. After closed-circuit flotation, excellent indices were obtained with grade of siderite concentrate of 36.49%, recovery rate of 10.65%, and loss on ignition of 11.17%, and the grade of hematite concentrate reached 66.27%, with recovery rate of 78.25%, tailing grade of 16.22%, and recovery rate of 11.10%. To analyze the mechanism of action from W-2 to quartz and siderite, zeta potential and FTIR spectra were detected. Results showed that after reaction with W-2, the zeta potential of quartz and siderite evidently changed, which resulted from hydrogen bond between quartz and W-2, and a certain chemical action between siderite and W-2. In addition, the electronegativity equalization principle was used to calculate electronegativity of active adsorption sites and analysis on reagent molecular structure showed that W-2 molecule had five active adsorption sites. Results showed that the electronegativity of atoms N and O in W-2 presented a substantial increase, and the synergy of atomic sites allowed considerable enhancement of collecting ability.

  4. Occurrence mechanism of silicate and aluminosilicate minerals in Sarcheshmeh copper flotation concentrate

    Institute of Scientific and Technical Information of China (English)

    H.R. Barkhordari; E. Jorjani; A. Eslami; M. Noaparast

    2009-01-01

    The Sarcheshmeh copper flotation circuit is producing 5×10~4 t copper concentrate per month with an averaging grade of 28% Cu in rougher, cleaner and reeleaner stages. In recent years, with the increase in the open pit depth, the content of aluminosili- cate minerals increased in plant feed and subsequently in flotation concentrate. It can motivate some problems, such as unwanted consumption of reagents, decreasing of the copper concentrate grade, increasing of Al_2O_3 and SiO_2 in the copper concentrate, and needing a higher temperature in the smelting process. The evaluation of the composite samples related to the most critical working period of the plant shows that quartz, illite, biotite, chlorite, orthoclase, albeit, muscovite, and kaolinite are the major Al_2O_3 and SiO_2 beating minerals that accompany chalcopyrite, chalcoeite, and covellite minerals in the plant feed. The severe alteration to clay min-erals was a general rule in all thin sections that were prepared from the plant feed. Sieve analysis of the flotation concentrate shows that Al_2O_3 and SiO_2 bearing minerals in the flotation concentrate can be decreased by promoting the size reduction from 53 to 38 μm. Interlocking of the Al_2O_3 and SiO_2 beating minerals with ehalcopyrite and ehalcocite is the occurrence mechanism of silicate and aluminosilicate minerals in the flotation concentrate. The dispersed form of interlocking is predominant.

  5. The Influence of Roasting Temperature on the Flotation Properties of Muscovite

    Directory of Open Access Journals (Sweden)

    Jiayan Tang

    2016-06-01

    Full Text Available Roasting and flotation are common techniques used in mineral processing, and they have increasingly been combined for the pre-concentration of muscovite from stone coal. The research was mainly to study flotation properties of muscovite after roasting at 200, 400, 600, 800 and 1000 °C, respectively. The changes of chemical and physical properties of muscovite during the roasting process were investigated by thermogravimetric analysis (TGA, Fourier transform infrared spectrum (FTIR, X-ray diffraction (XRD, X-ray photoelectron spectroscopy (XPS, Zeta potential measurements, particle size analysis, and the BET surface area measurements. The results indicated that the dehydroxylation of crystal structure took place at temperatures over 600 °C. A large number of hydroxyl groups were removed from the crystal structure of muscovite at 600–1000 °C. The layer structure, surface element distribution, and electrical properties of muscovite remained after roasting. The flotation recovery of roasted muscovite samples increased with the increase in roasting temperature in the same flotation system, because the specific surface and the adsorption capacity of dodecylamine (DDA were reduced when roasting temperature was over 600 °C. A suitable roasting temperature and dosage of reagents can be provided for the roasting-flotation of muscovite.

  6. A study of the interfacial chemistry of pyrite and coal in fine coal cleaning using flotation

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Chengliang [Univ. of Kentucky, Lexington, KY (United States)

    1993-01-01

    Surface oxidation, surface charge, and flotation properties have been systematically studied for coal, coal-pyrite and ore-pyrite. Electrochemical studies show that coal-pyrite exhibits much higher and more complex surface oxidation than ore-pyrite and its oxidation rate depends strongly on the carbon/coal content. Flotation studies indicate that pyrites have no self-induced floatability. Fuel oil significantly improves the floatability of coal and induces considerable flotation for coal-pyrite due to the hydrophobic interaction of fuel oil with the carbon/coal inclusions on the pyrite surface. Xanthate is a good collector for ore-pyrite but a poor collector for coal and coal-pyrite. The results from thermodynamic calculations, flotation and zeta potential measurements show that iron ions greatly affect the flotation of pyrite with xanthate and fuel oil. Various organic and inorganic chemicals have been examined for depressing coal-pyrite. It was found, for the first time, that sodium pyrophosphate is an effective depressant for coal-pyrite. Solution chemistry shows that pyrophosphate reacts with iron ions to form stable iron pyrophosphate complexes. Using pyrophosphate, the complete separation of pyrite from coal can be realized over a wide pH range at relatively low dosage.

  7. Application of petrography to tailings from coal flotation. Aplicacao da petrografia no beneficiamento de carvao por flotacao

    Energy Technology Data Exchange (ETDEWEB)

    Porphirio, N.H.

    1981-01-01

    Petrographic and chemical analyses were carried out on tailings from the flotation of coal. Results were correlated and analysed according to the conditions during each flotation test. Problems related to the manufacture of coal briquettes are outlined. The petrography of the macerals and microlithotypes and the reflectivity of vitrinite were studied and correlated with volatile matter. (5 refs.)

  8. New inovation and improvments in lead and conc. For selective flotation for lead-zink mine Sasa

    OpenAIRE

    2011-01-01

    New improvement in technological process from collective to selective lead and zinc flotation, renewed recent and advanced equipments, new flotation flowsheet with increased recovery and quality in lead and zinc concentrates. Many advantages in other sections of the concentrator, better financial results with appropriate environmental approaches eith ensured conditions in tailing dam, improvement in refused mine water in the surrounding river.

  9. Preliminary study on collectorless flotation of chalcocite, bornite and copper-bearing shale in the presence of selected frothers

    Directory of Open Access Journals (Sweden)

    Drzymala Jan

    2016-01-01

    Full Text Available Flotation of carbonaceous copper-bearing shale and copper sulfide minerals such as chalcocite and bornite in the presence of only frother was investigated. It was determined that all investigated solids did not float in pure water in the absence of flotation reagents. However, an addition of a frother rendered both shale and bornite floatable, while the recovery of chalcocite was negligible. These findings suggest that removal of carbonaceous matter from the ore by the so-called pre-flotation process can be a suitable procedure to reduce the amount of organic carbon in the concentrates provided that the feed does not contain bornite. Otherwise, simple pre-flotation must be replaced with a more sophisticated process in which flotation of bornite is suppressed.

  10. Quantification of Campylobacter spp. in chicken rinse samples by using flotation prior to real-time PCR

    DEFF Research Database (Denmark)

    Wolffs, Petra; Norling, Börje; Hoorfar, Jeffrey

    2005-01-01

    that densities changed at different time points during growth; however, all varied between 1.065 and 1.109 g/ml. These data were then used to develop a flotation assay. Results showed that after flotation and real-time PCR, cell concentrations as low as 8.6 X 10(2) CFU/ml could be detected without culture...... enrichment and amounts as low as 2.6 X 10(3) CFU/ml could be quantified. Furthermore, subjecting viable cells and dead cells to flotation showed that viable cells were recovered after flotation treatment but that dead cells and/or their DNA was not detected. Also, when samples containing VNC cells mixed......, real-time PCR has been combined with a novel discontinuous buoyant density gradient method, called flotation, in order to allow detection of only viable and VNC cells of thermotolerant campylobacters in chicken rinse samples. Studying the buoyant densities of different Campylobacter spp. showed...

  11. Flotation of kaolinite and diaspore with hexadecyl dimethyl benzyl ammonium chloride

    Institute of Scientific and Technical Information of China (English)

    HU Yue-hua; OUYANG Kui; CAO Xue-feng; ZHANG Li-min

    2008-01-01

    Tertiary amine was synthesized from fatty amine and formaldehyde. And then the synthesized tertiary amine was used toreact with benzyl chloride to synthesize hexadecyl dimethyl benzyl ammonium chloride (1627) at ambient pressure. Using thesynthesized 1627 as collector, the flotation properties of diaspore and kaolinite were investigated by single mineral and mixedmineral test. The flotation mechanism of diaspore, kaolinite and 1627 was discussed based on FTIR spectra. The results show that themass ratio of aluminum to silicate achieves 15.02 and the recovery of alumina in concentrate is 43.07% using 1627 as a collector. The 1627 is found to be a more effective and a promising collector for reverse flotation to remove aluminum-silicate minerals frombauxite.

  12. Depressing effect of phenoxyl acetic acids on flotation of minerals containing Ca2+/Mg2+ gangues

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Phenoxyl acetic acids were applied to determine their depressing effect on minerals containing Ca2+/Mg2+ gangues. Calcite,mixture of calcite and fluorite, and nickel ore were used in the flotation. And the depression mechanism was studied by the determination of contact angle, zeta potential, adsorptive capacity of collector, and IR analysis as well. It is found that 0.1 mmol/L of phenoxyl acetic acid derived from pyrogallol or gallic acid exhibits strong depressing ability on calcite in almost zero yields at pH value of 9.8, and calcite can be depressed in the flotation of calcite/fluorite mixture for approximate 87% yield of fluorite. The flotation result of practical nickel ore containing serpentine indicates that these two depressants may also show better depression performance to serpentine than traditional depressants such as sodium fluosilicate and carboxylmethyl cellulose. Analysis for the depression mechanism reveals that there exists strong chemical interaction between the depressants and minerals.

  13. REDUCING FIBER LOSS IN LABORATORY-AND MILL-SCALE FLOTATION DEINKING USING SURFACTANT SPRAY TECHNOLOGY

    Institute of Scientific and Technical Information of China (English)

    Greg.DeLozier; YulinZhao; YulinDeng; DavidWhite; JunyongZhu; MarkPrein

    2004-01-01

    As the cost of quality waste paper continues to escalate in response tofor the finite resource,an increased global demand loss of saleable fiber within flotation rejects becomes both environmentally and economically unacceptable. The ability of surfactant spray technology to reduce yield loss without detriment to pulp brightness gains has been demonstrated during both laboratory-and pilot-scale flotation deinking investigations. This paper documents the successful transfer of this technology to a single flotation unit within the deinking line of a mill producing newsprint from 100% secondary fiber. Initial results suggest that the loss of fiber across the unit may be reduced by more than 50% without obvious detriment to final pulp quality.

  14. REDUCING FIBER LOSS IN LABORATORY- AND MILL-SCALE FLOTATION DEINKING USING SURFACTANT SPRAY TECHNOLOGY

    Institute of Scientific and Technical Information of China (English)

    Greg. DeLozier; Yulin Zhao; Yulin Deng; David White; Junyong Zhu; Mark Prein

    2004-01-01

    As the cost of quality waste paper continues to escalate in response to an increased global demand for the finite resource, loss of saleable fiber within flotation rejects becomes both environmentally and economically unacceptable. The ability of surfactant spray technology to reduce yield loss without detriment to pulp brightness gains has been demonstrated during both laboratory- and pilot-scale flotation deinking investigations. This paper documents the successful transfer of this technology to a single flotation unit within the deinking line of a mill producing newsprint from 100% secondary fiber. Initial results suggest that the loss of fiber across the unit may be reduced by more than 50%without obvious detriment to final pulp quality.

  15. Prediction of operational parameters effect on coal flotation using artificial neural network

    Institute of Scientific and Technical Information of China (English)

    E. Jorjani; Sh. Mesroghli; S. Chehreh Chelgani

    2008-01-01

    Artificial neural network procedures were used to predict the combustible value (i.e. 100-Ash) and combustible recovery of coal flotation concentrate in different operational conditions. The pulp density, pH, rotation rate, coal particle size, dosage of collector, frother and conditioner were used as inputs to the network. Feed-forward artificial neural networks with 5-30-2-1 and 7-10-3-1 arrangements were capable to estimate the combustible value and combustible recovery of coal flotation concentrate respectively as the outputs. Quite satisfactory correlations of 1 and 0.91 in training and testing stages for combustible value and of 1 and 0.95 in training and testing stages for combustible recovery prediction were achieved. The proposed neural network models can be used to determine the most advantageous operational conditions for the expected concentrate assay and recovery in the coal flotation process.

  16. Modelling of the dispersed air flotation process applied to dairy wastewater treatment

    Directory of Open Access Journals (Sweden)

    F. P. Puget

    2004-06-01

    Full Text Available The aim of this work was to develop a mathematical model for a continuously operating flotation tank to provide the scale-up and optimization of the separation system. The fluid dynamic of the tank was assumed to be a perfect mixture and the flotation kinetics to be a first-order reaction, as suggested by the batch operation. The experiments were carried out in a continuously operating 60 L tank, used in the treatment of a synthetic dairy waste at its isoelectric point. A mathematical model that describes the behavior of a continuously operating flotation tank used in the treatment of a synthetic dairy waste at its isoelectric point is not only proposed, but also validated with experimental data.

  17. Utilization of starch graft copolymers as selective depressants for lizardite in the flotation of pentlandite

    Science.gov (United States)

    Cao, Jian; Luo, Yong-Chun; Xu, Guo-Qiang; Qi, Li; Hu, Xiu-Qin; Xu, Peng-Fei; Zhang, Liu-Yi; Cheng, Shao-Yi

    2015-05-01

    This paper investigates the detrimental effect of lizardite surface characteristics on pentlandite flotation. To reduce the effect, two different starch graft copolymers, starch-graft-polyacrylamide (S-g-PAM) and starch-graft-polyacrylic acid (S-g-PAA) were synthesized as depressants for lizardite. The flotation results show that at pH value of 8, where the flotation of lizardite and pentlandite are routinely performed, S-g-PAM and S-g-PAA improve pentlandite recovery efficiently, compared with the traditional depressant carboxymethyl cellulose (CMC). Experimental results demonstrate that S-g-PAM and S-g-PAA disperse the hydrophilic lizardite particles from the pentlandite surface and also flocculate lizardite particles.

  18. A review of factors that affect contact angle and implications for flotation practice.

    Science.gov (United States)

    Chau, T T; Bruckard, W J; Koh, P T L; Nguyen, A V

    2009-09-30

    Contact angle and the wetting behaviour of solid particles are influenced by many physical and chemical factors such as surface roughness and heterogeneity as well as particle shape and size. A significant amount of effort has been invested in order to probe the correlation between these factors and surface wettability. Some of the key investigations reported in the literature are reviewed here. It is clear from the papers reviewed that, depending on many experimental conditions such as the size of the surface heterogeneities and asperities, surface cleanliness, and the resolution of measuring equipment and data interpretation, obtaining meaningful contact angle values is extremely difficult and such values are reliant on careful experimental control. Surface wetting behaviour depends on not only surface texture (roughness and particle shape), and surface chemistry (heterogeneity) but also on hydrodynamic conditions in the preparation route. The inability to distinguish the effects of each factor may be due to the interplay and/or overlap of two or more factors in each system. From this review, it was concluded that: Surface geometry (and surface roughness of different scales) can be used to tune the contact angle; with increasing surface roughness the apparent contact angle decreases for hydrophilic materials and increases for hydrophobic materials. For non-ideal surfaces, such as mineral surfaces in the flotation process, kinetics plays a more important role than thermodynamics in dictating wettability. Particle size encountered in flotation (10-200 microm) showed no significant effect on contact angle but has a strong effect on flotation rate constant. There is a lack of a rigid quantitative correlation between factors affecting wetting, wetting behaviour and contact angle on minerals; and hence their implication for flotation process. Specifically, universal correlation of contact angle to flotation recovery is still difficult to predict from first principles

  19. A saltwater flotation technique to identify unincubated eggs

    Science.gov (United States)

    Devney, C.A.; Kondrad, S.L.; Stebbins, K.R.; Brittingham, K.D.; Hoffman, D.J.; Heinz, G.H.

    2009-01-01

    Field studies on nesting birds sometimes involve questions related to nest initiation dates, length of the incubation period, or changes in parental incubation behavior during various stages of incubation. Some of this information can be best assessed when a nest is discovered before the eggs have undergone any incubation, and this has traditionally been assessed by floating eggs in freshwater. However, because the freshwater method is not particularly accurate in identifying unincubated eggs, we developed a more reliable saltwater flotation method. The saltwater method involves diluting a saturated saltwater solution with freshwater until a salt concentration is reached where unincubated eggs sink to the bottom and incubated eggs float to the surface. For Laughing Gulls (Leucophaeus atricilla), floating eggs in freshwater failed to identify 39.0% (N = 251) of eggs that were subsequently found by candling to have undergone incubation prior to collection. By contrast, in a separate collection of gull eggs, no eggs that passed the saltwater test (N = 225) were found by a later candling to have been incubated prior to collection. For Double-crested Cormorants (Phalacrocorax auritus), floating eggs in freshwater failed to identify 15.6% (N = 250) of eggs that had undergone incubation prior to collection, whereas in a separate collection, none of the eggs that passed the saltwater test (N = 85) were found by a later candling to have been incubated prior to collection. Immersion of eggs in saltwater did not affect embryo survival. Although use of the saltwater method is likely limited to colonial species and requires calibrating a saltwater solution, it is a faster and more accurate method of identifying unincubated eggs than the traditional method of floating eggs in freshwater.

  20. Performance Comparison between Neutralization Tailings and Flotation Tailings Used for Backfill Mix and Mechanism Analysis

    OpenAIRE

    Bin Han; Wei Sun; Shaofeng Yu; Chao Liu; Song Yao; Jianxun Wu

    2016-01-01

    A comparison test of different tailings used for underground backfill was conducted, using neutralized tailings from BIOX and flotation tailings of Jinfeng Mine. Laboratory comparison test results show that, with neutralized tailings, when the cement dosage is at 19%, backfill UCS after 7 days, 14 days, and 28 days are 105%–163%, 80%–102%, and 33%–43%, respectively, which are higher than those of flotation tailings. When the cement dosage is at 12%, backfill UCS after 7 days, 14 days, and 28 ...

  1. Effects of organic and inorganic additives on flotation recovery of washed cells of Saccharomyces cerevisiae resuspended in water.

    Science.gov (United States)

    DeSousa, Sandro Rogério; Laluce, Cecilia; Jafelicci, Miguel

    2006-03-01

    Separation of microbial cells by flotation recovery is usually carried out in industrial reactors or wastewater treatment systems, which contain a complex mixture of microbial nutrients and excretion products. In the present study, the separation of yeast cells by flotation recovery was carried out using a simple flotation recovery systems containing washed yeast cells resuspended in water in order to elucidate the effects of additives (defined amounts of organic and inorganic acids, ethanol, surfactants and sodium chloride) on the cellular interactions at interfaces (cell/aqueous phase and cell/air bubble). When sodium chloride, organic acids (notably propionic, succinic and acetic acids) and organic surfactants (sodium dodecyl sulphate (SDS), cetyltrimethylammonium bromide (CTAB) and Nonidet P40) were added to the flotation recovery system, significant increases in the cell recovery of yeast hydrophobic cells (Saccharomyces cerevisiae, strain FLT-01) were observed. The association of ethanol to acetic acid solution (a minor by-product of alcoholic fermentation) in the flotation recovery system, containing washed cells of strain FLT-01 resuspended in water, leading to an increased flotation recovery at pH 5.5. Thus, the association among products of the cellular metabolism (e.g., ethanol and acetic acid) can improve yeast cell recovery by flotation recovery.

  2. Enhanced phosphorus removal in the DAF process by flotation scum recycling for advanced treatment of municipal wastewater.

    Science.gov (United States)

    Kwak, Dong-Heui; Lee, Ki-Cheol

    2015-01-01

    To remove phosphorus (P) from municipal wastewater, various types of advanced treatment processes are being actively applied. However, there is commonly a space limit in municipal wastewater treatment plants (MWTPs). For that reason, the dissolved air flotation (DAF), which is well known for small space and flexible application process, is preferred as an additive process to enhance the removal of P. A series of experiments were conducted to investigate the feasibility of flotation scum recycling for effective P removal from a MWTP using a DAF pilot plant over 1 year. The average increases in the removal efficiencies due to flotation scum recycling were 22.6% for total phosphorus (T-P) and 18.3% for PO4-P. A higher removal efficiency of T-P was induced by recycling the flotation scum because a significant amount of Al components remained in the flotation scum. The increase in T-P removal efficiency, due to the recycling of flotation scum, shifted from the boundary of the stoichiometric precipitate to the equilibrium control region. Flotation scum recycling may contribute to improving the quality of treated water and reducing treatment costs by minimizing the coagulant dosage required.

  3. Seed flotation and germination of salt marsh plants: The effects of stratification, salinity, and/or inundation regime

    Science.gov (United States)

    Elsey-Quirk, T.; Middleton, B.A.; Proffitt, C.E.

    2009-01-01

    We examined the effects of cold stratification and salinity on seed flotation of eight salt marsh species. Four of the eight species were tested for germination success under different stratification, salinity, and flooding conditions. Species were separated into two groups, four species received wet stratification and four dry stratification and fresh seeds of all species were tested for flotation and germination. Fresh seeds of seven out of eight species had flotation times independent of salinity, six of which had average flotation times of at least 50 d. Seeds of Spartina alterniflora and Spartina patens had the shortest flotation times, averaging 24 and 26 d, respectively. Following wet stratification, the flotation time of S. alterniflora seeds in higher salinity water (15 and 36 ppt) was reduced by over 75% and germination declined by more than 90%. Wet stratification reduced the flotation time of Distichlis spicata seeds in fresh water but increased seed germination from 2 to 16% in a fluctuating inundation regime. Fresh seeds of Iva frutescens and S. alternflora were capable of germination and therefore are non-dormant during dispersal. Fresh seeds of I. frutescens had similar germination to dry stratified seeds ranging 25-30%. Salinity reduced seed germination for all species except for S. alterniflora. A fluctuating inundation regime was important for seed germination of the low marsh species and for germination following cold stratification. The conditions that resulted in seeds sinking faster were similar to the conditions that resulted in higher germination for two of four species. ?? 2009 Elsevier B.V.

  4. On the influence of the hydrodynamics in flotation process. - Effects of process on the residence time distribution in a continuously operated flotation machine. Beitrag zum Einfluss der Hydrodynamik beim Flotationsprozess. - Charakteristika der Verweilzeitverteilungsfunktion im Trogflotationsapparat

    Energy Technology Data Exchange (ETDEWEB)

    Bischofberger, C.; Koch, P.

    1986-01-01

    The papers deal with the possible descriptions of turbulent flows and measuring method with piezoelectrical sensors. Experimental tests on the sylvinite flotation and tin ore flotation for optimizing hydrodynamics were meant to clarity the influence of design, speed and specific air flow. In semi-industrial and industrial scale was investigated the residence time distribution in a continuously operated flotation bank. The mixing behaviour was quantitatively analysed by variations some important parameters. The 2 papers have been abstracted separately. (orig./MOS) With 53 figs., 10 tabs., 74 refs.

  5. Isolation and characterization of lost copper and molybdenum particles in the flotation tailings of Kennecott copper porphyry ores

    Science.gov (United States)

    Tserendavga, Tsend-Ayush

    The importance of flotation separation has long been, and continues to be, an important technology for the mining industry, especially to metallurgical engineers. However, the flotation process is quite complex and expensive, in addition to being influenced by many variables. Understanding the variables affecting flotation efficiency and how valuable minerals are lost to the tailings gives metallurgists an advantage in their attempts to increase efficiency by designing operations to target the areas of greatest potential value. A successful, accurate evaluation of lost minerals in the tailings and appropriate solutions to improve flotation efficiency can save millions of dollars in the effective utilization of our mineral resources. In this dissertation research, an attempt has been made to understand the reasons for the loss of valuable mineral particles in the tailings from Kennecott Utah Copper ores. Possibilities include liberation, particle aggregation (slime coating) and surface chemistry issues associated with the flotation separation. This research generally consisted of three main aspects. The first part involved laboratory flotation experiments and factors, which affect the flotation efficiency. Results of flotation testing are reported that several factors such as mineral exposure/liberation and slime coating and surface oxidation strongly affect the flotation efficiency. The second part of this dissertation research was to develop a rapid scan dual energy (DE) methodology using 2D radiography to identify, isolate, and prepare lost sulfide mineral particles with the advantages of simple sample preparation, short analysis time, statistically reliable accuracy and confident identification. The third part of this dissertation research was concerned with detailed characterization of lost particles including such factors as liberation, slime coating, and surface chemistry characteristics using advanced analytical techniques and instruments. Based on the

  6. 46 CFR 117.72 - Personal flotation devices carried in addition to life jackets.

    Science.gov (United States)

    2010-10-01

    ... PASSENGERS LIFESAVING EQUIPMENT AND ARRANGEMENTS Ring Life Buoys and Life Jackets § 117.72 Personal flotation devices carried in addition to life jackets. (a) Equipment carried under this section is not acceptable in lieu of any portion of the required number of approved life jackets and must not be substituted for the...

  7. Treatment and Recycling of the Process Water in Iron Ore Flotation of Yuanjiacun Iron Mine

    Directory of Open Access Journals (Sweden)

    Wen-li Jiang

    2017-01-01

    Full Text Available Coagulating sedimentation and oxidation treatment of process water in iron ore flotation of Yuanjiacun iron mine had been studied. The process water of this mine carried residual polyacrylamide (PAM, poly(diallyldimethylammonium chloride (PDADMAC, and Ca2+ from the flotation and caused decrease of the iron flotation recovery or grade of the concentrate. The studies on high-intensity magnetic separation (HIMS tailings for coagulating sedimentation showed that the settling performance of coagulant (named CYH was better than that of PDADMAC. The analyses of FTIR spectra and zeta potential demonstrated that CYH is adsorbed mainly through electrostatic attraction onto HIMS tailings. Sodium hypochlorite was adopted to oxidize the residual organics in tailings wastewater. When sodium hypochlorite is at the dosage of 1.0 g/L, reaction temperature is of 20°C, and reaction time is of 30 minutes, the removal rates of PAM, COD, and Ca2+ were 90.48%, 83.97%, and 85.00%, respectively. Bench-scale flotation studies on the treated tailings wastewater indicated that the iron recovery and grade of concentrate were close to those of freshwater.

  8. Copper Recovery from Yulong Complex Copper Oxide Ore by Flotation and Magnetic Separation

    Science.gov (United States)

    Han, Junwei; Xiao, Jun; Qin, Wenqing; Chen, Daixiong; Liu, Wei

    2017-09-01

    A combined process of flotation and high-gradient magnetic separation was proposed to utilize Yulong complex copper oxide ore. The effects of particle size, activators, Na2S dosage, LA (a mixture of ammonium sulfate and ethylenediamine) dosage, activating time, collectors, COC (a combination collector of modified hydroxyl oxime acid and xanthate) dosage, and magnetic intensity on the copper recovery were investigated. The results showed that 74.08% Cu was recovered by flotation, while the average grade of the copper concentrates was 21.68%. Another 17.34% Cu was further recovered from the flotation tailing by magnetic separation at 0.8 T. The cumulative recovery of copper reached 91.42%. The modifier LA played a positive role in facilitating the sulfidation of copper oxide with Na2S, and the combined collector COC was better than other collectors for the copper flotation. This technology has been successfully applied to industrial production, and the results are consistent with the laboratory data.

  9. The Effects of Calcium Ions on the Flotation of Sillimanite Using Dodecylammonium Chloride

    Directory of Open Access Journals (Sweden)

    Zhijie Chen

    2017-02-01

    Full Text Available The effects of Ca2+ ions on the flotation of sillimanite using dodecylammonium chloride as a collector were investigated by micro-flotation tests, zeta potential measurements, solution chemistry analysis and molecular dynamics (MD simulation. The micro-flotation results indicated that Ca2+ ions remarkably inhibit the flotation of sillimanite in the pH range of 2.0–9.0. The point of zero charge (PZC of sillimanite changed from 5.4 to 6.1 with the addition of Ca2+ ions. Meanwhile, the calculated concentration of RNH3+ in the sillimanite interface layer decreased in the presence of Ca2+ ions. The results of MD simulation revealed that Ca2+ ions have strong binding energy with the sillimanite (010 surface, and the binding energy of RNH3+ with sillimanite (010 surface reduced in the presence of Ca2+ ions. The conclusions drawn from the computations are in good agreement with the experimental results.

  10. Optimization of chemical composition in the manufacturing process of flotation balls based on intelligent soft sensing

    Directory of Open Access Journals (Sweden)

    Dučić Nedeljko

    2016-01-01

    Full Text Available This paper presents an application of computational intelligence in modeling and optimization of parameters of two related production processes - ore flotation and production of balls for ore flotation. It is proposed that desired chemical composition of flotation balls (Mn=0.69%; Cr=2.247%; C=3.79%; Si=0.5%, which ensures minimum wear rate (0.47 g/kg during copper milling is determined by combining artificial neural network (ANN and genetic algorithm (GA. Based on the results provided by neuro-genetic combination, a second neural network was derived as an ‘intelligent soft sensor’ in the process of white cast iron production. The proposed ANN 12-16-12-4 model demonstrated favourable prediction capacity, and can be recommended as a ‘intelligent soft sensor’ in the alloying process intended for obtaining favourable chemical composition of white cast iron for production of flotation balls. In the development of intelligent soft sensor data from the two real production processes was used. [Projekat Ministarstva nauke Republike Srbije, br. TR35037 i br. TR35015

  11. New influence factor inducing difficulty in selective flotation separation of Cu-Zn mixed sulfide minerals

    Science.gov (United States)

    Deng, Jiu-shuai; Mao, Ying-bo; Wen, Shu-ming; Liu, Jian; Xian, Yong-jun; Feng, Qi-cheng

    2015-02-01

    Selective flotation separation of Cu-Zn mixed sulfides has been proven to be difficult. Thus far, researchers have found no satisfactory way to separate Cu-Zn mixed sulfides by selective flotation, mainly because of the complex surface and interface interaction mechanisms in the flotation solution. Undesired activation occurs between copper ions and the sphalerite surfaces. In addition to recycled water and mineral dissolution, ancient fluids in the minerals are observed to be a new source of metal ions. In this study, significant amounts of ancient fluids were found to exist in Cu-Zn sulfide and gangue minerals, mostly as gas-liquid fluid inclusions. The concentration of copper ions released from the ancient fluids reached 1.02 × 10-6 mol/L, whereas, in the cases of sphalerite and quartz, this concentration was 0.62 × 10-6 mol/L and 0.44 × 10-6 mol/L, respectively. As a result, the ancient fluid is a significant source of copper ions compared to mineral dissolution under the same experimental conditions, which promotes the unwanted activation of sphalerite. Therefore, the ancient fluid is considered to be a new factor that affects the selective flotation separation of Cu-Zn mixed sulfide ores.

  12. The Flotation System Optimization in Alborz-Sharghi Coal Washing Plant; A Laboratory Study

    Directory of Open Access Journals (Sweden)

    Ahmad Fattahi Mejlej

    2015-06-01

    Full Text Available This paper tries to determine an optimum condition for the flotation operation of the Alborz-Sharghi coal washing plant. For this purpose, a series of comprehensive experiments have been conducted on representative samples from feed of the flotation system of the plant. Four operational variables such as the collector dosage (Fuel oil, the frother dosages (MIBC, the pulp density percent and the impeller speed were taken into account. After obtaining representative samples, 81 required experiments were designed using the orthogonal array (34 of Taguchi method. Three levels of the variables amount including low, base and high were considered for the experiments. The most obvious finding to emerge from this study was that the optimum flotation recovery (61.09 % is obtained in the base level (L-2 of the collector dosage, the lowest level (L-1 of MIBC and the highest levels (L-3 of the pulp density and the impeller speed. The sensitivity analysis of the variables also indicated that the increase in the collector dosage causes to increase in the total recovery of the flotation and the coal quality. Besides, the largest effect on total recovery was clearly related to the pulp density levels. The increase in values of the pulp density causes to decrease in the recovery values.

  13. Performance Comparison between Neutralization Tailings and Flotation Tailings Used for Backfill Mix and Mechanism Analysis

    Directory of Open Access Journals (Sweden)

    Bin Han

    2016-01-01

    Full Text Available A comparison test of different tailings used for underground backfill was conducted, using neutralized tailings from BIOX and flotation tailings of Jinfeng Mine. Laboratory comparison test results show that, with neutralized tailings, when the cement dosage is at 19%, backfill UCS after 7 days, 14 days, and 28 days are 105%–163%, 80%–102%, and 33%–43%, respectively, which are higher than those of flotation tailings. When the cement dosage is at 12%, backfill UCS after 7 days, 14 days, and 28 days are 58%–77%, 50%–60%, and 28%–51%, respectively, which are higher than those of flotation tailings. Slurry fluidity of neutralized tailings is lower than that of flotation tailings, while, in these two tailings, the difference of slump and diffusivity values is less than 6%, which is not a significant difference in slurry fluidity. The reason for neutralized tailings showing higher UCS is as follows: during backfill curing, neutralization tailings produce abundant crystals of CaSO4·2H2O in interlaced structure which helps in combining aggregates closely; CaSO4·2H2O hydrates with C3A C4AF contained in the cement and forms clavate cement bacillus which works as a micro reinforcing steel bar. The test proved that neutralized tailings are more optimal for backfilling.

  14. Enhancing organic matter removal in desalination pretreatment systems by application of dissolved air flotation

    DEFF Research Database (Denmark)

    Shutova, Yulia; Karna, Barun Lal; Hambly, Adam C.

    2016-01-01

    Membrane fouling in reverse osmosis (RO) systems caused by organic matter (OM) remains a significant operational issue during desalination. Dissolved air flotation (DAF) has recently received attention as a pre-treatment option for seawater OM removal; however, only a limited number of studies have...

  15. Sensory Isolation in Flotation Tanks: Altered States of Consciousness and Effects on Well-Being

    Science.gov (United States)

    Kjellgren, Anette; Lyden, Francisca; Norlander, Torsten

    2008-01-01

    A qualitative analysis (The Empirical Phenomenological Psychological method) of interviews involving eight patients (depression, burn-out syndrome, and chronic pain) was carried out in order to obtain knowledge regarding the effects of flotation tank therapy. This knowledge might be helpful for both professionals and potential floaters. The…

  16. Beneficiation of low grade graphite ore of eastern India by two-stage grinding and flotation

    Directory of Open Access Journals (Sweden)

    Vasumathi N.

    2014-01-01

    Full Text Available A low grade graphite run-of-mine (r.o.m ore from eastern India was studied for its amenability to beneficiation by flotation technique. The petrography studies indicate that the ore primarily consists of quartz and graphite with minor quantity of mica. It analyzed 89.89% ash and 8.59% fixed carbon. The ore was crushed in stages followed by primary coarse wet grinding to 212 μm (d80. Rougher flotation was carried out in Denver flotation cell to eliminate gangue as much as possible in the form of primary tailings with minimal loss of carbon. Diesel & pine oil were used as collector and frother respectively. Regrinding of rougher concentrate to150 μm (d80 was resorted to further liberate the graphite values and was followed by multi-stage cleaning. This two-stage grinding approach involving a primary coarse grinding and regrinding of rougher float followed by its multi-stage cleaning was found to yield required grade of concentrate for applications such as refractories, batteries and high temperature lubricants. This approach is supposed to retain the flake size of coarse, free and liberated graphite, if available, during primary coarse grinding and rougher flotation stage with minimal grinding energy costs as against the usual practice of single stage grinding in the case of many ores. A final concentrate of 8.97% weight recovery with 5.80% ash and 92.13% fixed carbon could be achieved.

  17. The Activation Mechanism of Bi3+ Ions to Rutile Flotation in a Strong Acidic Environment

    Directory of Open Access Journals (Sweden)

    Wei Xiao

    2017-07-01

    Full Text Available Lead hydroxyl compounds are known as rutile flotation of the traditional activated component, but the optimum pH range for flotation is 2–3 using styryl phosphoric acid (SPA as collector, without lead hydroxyl compounds in slurry solution. In this study, Bi3+ ions as a novel activator was investigated. The results revealed that the presence of Bi3+ ions increased the surface potential, due to the specific adsorption of hydroxyl compounds, which greatly increases the adsorption capacity of SPA on the rutile surface. Bi3+ ions increased the activation sites through the form of hydroxyl species adsorbing on the rutile surface and occupying the steric position of the original Ca2+ ions. The proton substitution reaction occurred between the hydroxyl species of Bi3+ ions (Bi(OHn+(3−n and the hydroxylated rutile surface, producing the compounds of Ti-O-Bi2+. The micro-flotation tests results suggested that Bi3+ ions could improve the flotation recovery of rutile from 61% to 90%, and from 61% to 64% for Pb2+ ions.

  18. Study and Application of Flotation in Schemes for Waste Water Purification

    Directory of Open Access Journals (Sweden)

    Prof. dr. habil. Viktor Georgijevch Ponomarev

    2009-12-01

    Full Text Available Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} The paper analyzes the factors influencing water treatment by means of flotation. Author has come to a conclusion that one of the indices revealing flotation efficiency is surface tension of the water phase. The paper presents dependencies of this index on some parameters. In addition, the paper analyzes applicable constructions of flotators. Preference is given to impeller flotation due to its suitability to application.

  19. Improvements in flotation technology in the Makeevka C and CW washeries

    Energy Technology Data Exchange (ETDEWEB)

    Lyadov, V.V.; Kovtunenko, E.N.; Ivashchenko, V.A.; Mosin, M.K.

    1981-01-01

    The Makeevka C and CW operates two washeries, each with a capacity of 2.5 million tons/year. Most of the coals come from the Donbas and have good to moderate cleanability, but in recent years both washeries have had to accept 10 to 12% of Pechora, Kuzbas, and Karagande coals. The flotation sections are vital elements in the processing flowsheets, since in addition to recovering coal substance from the slurry they contribute to the reclamation of washery water in circulation. The capacity of the flotation machines in the Makeeva C and CW washeries is relatively low, and the number of machines in each washery must therefore be increased to 4 to 5. The machines are consequently set up at low levels, which increases the labor and material costs of operating them. The future plans for the flotation sections envisage the installation of 900 to 1000 m/sup 3//h machines. The unit capacities of the vacuum filters must also be increased; it is planned to install filters with a filtration surface area of 140 m/sup 2/ or more each. These modifications will greatly simplify the processing flowsheet and facilitate full automation in the flotation and filtration sections.

  20. Flotation Separating Rutile from Calcium and Silicon Gangue Miner-als

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Rutile separation from calcite, apatite and quartz by flotation was investigated. The results show that the rutile separation from calcium and silicon gangue minerals can be realized with alkyl-imino-bismethylene phosphoric acid (TF112) as a collector and sodium hexametaphosphate (SH) as a regulator.

  1. Selective factors involved in oil flotation isolation of black yeasts from the environment

    NARCIS (Netherlands)

    Satow, M.M.; Attili-Angelis, D.; de Hoog, G.S.; Angelis, D.F.; Vicente, V.A.

    2008-01-01

    The oil flotation isolation technique has been successfully applied to recover chaetothyrialean black yeasts and relatives from the environment. The selective mechanisms playing a role in isolation are unknown. The fungi concerned are supposed to occupy specialized microniches in nature, taking adva

  2. Efficacy of brown sugar flotation and hot water methods for detecting Rhagoletis indifferens (Dipt., Tephritidae) larvae

    Science.gov (United States)

    The brown sugar flotation and hot water methods are accepted procedures for detecting larval western cherry fruit fly, Rhagoletis indifferens Curran, in sweet cherry [Prunus avium (L.) L.] and could be included in a systems approach for showing the absence of larvae in fruit. The methods require cr...

  3. Psychotherapeutic Treatment in Combination with Relaxation in a Flotation Tank: Effects on "Burn-Out Syndrome"

    Science.gov (United States)

    Kjellgren, Anette; Buhrkall, Hanne; Norlander, Torsten

    2010-01-01

    The focus of this study was to investigate experiences gained from treatment combining relaxation in flotation tank with psychotherapy for sufferers from "burn-out syndrome". Six people participated in a ten week program. They were all interviewed; the data were analyzed using the Empirical Phenomenological Psychological method. Five…

  4. Flotation of Mineral and Dyes: A Laboratory Experiment for Separation Method Molecular Hitchhikers

    Science.gov (United States)

    Rappon, Tim; Sylvestre, Jarrett A.; Rappon, Manit

    2016-01-01

    Flotation as a method of separation is widely researched and is applied in many industries. It has been used to address a wide range of environmental issues including treatment of wastewater, recovery of heavy metals for recycling, extraction of minerals in mining, and so forth. This laboratory attempts to show how such a simple method can be used…

  5. Flotation Behaviors of Perovskite, Titanaugite, and Magnesium Aluminate Spinel Using Octyl Hydroxamic Acid as the Collector

    Directory of Open Access Journals (Sweden)

    Weiqing Wang

    2017-08-01

    Full Text Available The flotation behaviors of perovskite, titanaugite, and magnesium aluminate spinel (MA-spinel, using octyl hydroxamic acid (OHA as the collector, were investigated using microflotation experiments, zeta-potential measurements, Fourier transform infrared (FT-IR analyses, X-ray photoelectron spectroscopy (XPS analyses, and flotation experiments on artificially mixed minerals. The microflotation experiments show that the floatability of perovskite is clearly better than titanaugite and MA-spinel at around pH 5.5, while titanaugite possesses certain floatability at pH 6.0–6.5, and MA-spinel displays good floatability at pH > 8.0. The results of the FT-IR and XPS analyses show that OHA mainly interacts with Ti, resulting in perovskite flotation, and that the Al on titanaugite, as well as the Mg and Al on the MA-spinel surface, chemically react with OHA under acidic conditions. However, OHA mainly reacts with the Ti and Ca on the perovskite surface, Ca and Mg on the titanaugite surface, and Mg and Al on the MA-spinel surface under alkaline conditions. The results of the artificially mixed mineral flotation experiment show that the concentrate of TiO2 grade increased from 19.73% to 30.18% at pH 5.4, which indicates that a weakly acidic solution is the appropriate condition for the flotation separation of perovskite from titanaugite and MA-spinel. The results of the modified slag flotation experiments show that the TiO2 grade of concentrate increased from 18.13% to 23.88% at pH 5.4, through the open circuit test of “one roughing and one cleaning”. OHA displays selectivity toward perovskite in the modified slag flotation, but the consumption of H2SO4 is very high. The CaSO4 precipitate covered on the mineral surfaces results in poor TiO2 grade and recovery.

  6. The acute effects of flotation restricted environmental stimulation technique on recovery from maximal eccentric exercise.

    Science.gov (United States)

    Morgan, Paul M; Salacinski, Amanda J; Stults-Kolehmainen, Matthew A

    2013-12-01

    Flotation restricted environmental stimulation technique (REST) involves compromising senses of sound, sight, and touch by creating a quiet dark environment. The individual lies supine in a tank of Epsom salt and water heated to roughly skin temperature (34-35° C). This study was performed to determine if a 1-hour flotation REST session would aid in the recovery process after maximal eccentric knee extensions and flexions. Twenty-four untrained male students (23.29 ± 2.1 years, 184.17 ± 6.85 cm, 85.16 ± 11.54 kg) participated in a randomized, repeated measures crossover study. The participants completed 2 exercise and recovery protocols: a 1-hour flotation REST session and a 1-hour seated control (passive recovery). After isometric muscle strength testing, participants were fatigued with eccentric isokinetic muscle contractions (50 repetitions at 60°·s) of the nondominant knee extensors and flexors. Blood lactate, blood glucose, heart rate, OMNI-rating of perceived exertion for resistance exercise (OMNI-RPE), perceived pain, muscle soreness, and isometric strength were collected before exercise, after treatment, and 24 and 48 hours later. A multivariate analysis of covariance found that treatment had a significant main effect on blood lactate, whereas subsequent univariate analyses of variance found statistical significance with the immediate posttreatment blood lactate measures. The results indicate that flotation REST appears to have a significant impact on blood lactate and perceived pain compared with a 1-hour passive recovery session in untrained healthy men. No difference was found between conditions for muscle strength, blood glucose, muscle soreness, heart rate, or OMNI-RPE. Flotation REST may be used for recreational and professional athletes to help reduce blood lactate levels after eccentric exercise.

  7. Dissolved air flotation (DAF) for primary and tertiary treatment of municipal wastewaters.

    Science.gov (United States)

    Koivunen, J; Heinonen-Tanski, H

    2008-01-01

    Tertiary treatment of municipal wastewater by dissolved air flotation was studied on a pilot-scale. The effects of coagulant dose, flocculation pattern, dispersion water recycle ratio and hydraulic surface load on process performance were evaluated. The treatment of primary effluents by dissolved air flotation was investigated to assess the suitability of this process for the treatment of heavily polluted effluents and wastewater treatment plant by-passes. The tertiary dissolved air flotation process typically achieved 90-99% reductions in the numbers of enteric microbes (total coliforms, enterococci and F-RNA coliphages). The average reductions of total phosphorus and chemical oxygen demand were 55-81% and 28-39%, respectively. Increasing the polyaluminium chloride coagulant dose from 2 to 10 mgAl(3+) l(-1) and the dispersion water recycle ratio from 11 to 22% improved the efficiency of the process. Changes in the flocculation conditions (range of G-values 10-55 s(-1); retention time 4-8 min) and hydraulic surface load (5 or 10 m h(-1)) did not clearly affect the process efficiency. The dissolved air flotation process decreased the numbers of enteric microbes and reduced total phosphorus, chemical oxygen demand and suspended solids from the primary treated wastewaters on average by 98-99.8%, 90%, 47% and 77%, respectively. The dissolved air flotation process was demonstrated to be a suitable method for efficient tertiary treatment of wastewaters, as well as for the elimination of peak pollution loads or by-pass wastewaters during the treatment plant overloading situations.

  8. Summary of Available Guidance and Best Practices for Determining Suitability of Dredged Material for Beneficial Uses

    Science.gov (United States)

    2007-11-01

    Metals = arsenic, cadmium, chromium, copper , lead, mercury, silver, nickel, and zinc. Use EPA 1986 Method 245.6 for mercury determinations. Methods...contaminated sediment. USEPA (1994c) evaluated grain size separation, magnetic separation, gravity separation, attrition scrubbing, and froth flotation for...Potential applications of magnetic separation at Indiana Harbor, and froth flotation at Saginaw River, showed limited application. Francingues and

  9. The Hague Judgments Convention

    DEFF Research Database (Denmark)

    Nielsen, Peter Arnt

    2011-01-01

    The Hague Judgments Convention of 2005 is the first global convention on international jurisdiction and recognition and enforcement of judgments in civil and commercial matters. The author explains the political and legal background of the Convention, its content and certain crucial issues during...

  10. Removal of adsorbent particles od copper ions by Jet flotation; Remocion de particulas adsorbentes de iones cobre por flotacion Jet

    Energy Technology Data Exchange (ETDEWEB)

    Santander, M.; Tapia, P.; Pavez, O.; Valderrama, L.; Guzman, D.

    2009-07-01

    The present study shows the results obtained on the removal of copper ions from synthetic effluents by using the adsorbent particles flotation technique (APF) in a Jet flotation cell (Jameson type). In a typical experimental run, a mineral with high quartz content was used as adsorbent particles in the adsorption and flotation experiments, to determine optimal pH conditions, adsorbent particles concentration; flotation reagents dosage and air/effluent flow ratio for applying in the Jet cell to maximize the efficiency of copper ions adsorptions and the removal of particles adsorbents containing the absorbed copper ions. The results indicate the at pH>7 and at adsorbent particles concentration of 2 kg.m{sup -}3, 99% of copper ions is adsorbed and, when the air/effluent flow ratio applied in the Jet cell is 0,2, 98% of absorbent particles containing the adsorbed copper ions is removed. (Author) 39 refs.

  11. 煤泥的浮选试验研究%Flotation experimental study of the coal slime

    Institute of Scientific and Technical Information of China (English)

    缪长勇; 郭喜民

    2012-01-01

    That article illustrates the advantages, and takes the coal slime from some company as an example, a research is conducted that makes coMParison between flotation column and flotation machine. Eventually the results show that the flotation column is more predominant in reducing the ash in clean coal and improving the efficiency of sizing coMParing to the flotation machines.%该文阐述了浮选柱的优点,并以某选煤厂煤泥为例,分别进行了浮选柱与浮选机的对比试验研究。结果表明:浮选柱在降低精煤灰分、提高分选效率方面,浮选柱比浮选机具有显著的优越性。

  12. Dual effects of sodium sulfide on the flotation behavior of chalcopyrite:I. Effect of pulp potential

    Institute of Scientific and Technical Information of China (English)

    Bijan Taheri; Mahmoud Abdollahy; Sied Ziaedin Shafaei Tonkaboni; Soheyla Javadian; Mohammadreza Yarahmadi

    2014-01-01

    This study explores the flotation behavior of chalcopyrite in the presence of different concentrations of sodium sulfide (Na2S·9H2O) at pH 12 under controlled potential conditions. It was observed that the flotation of chalcopyrite is not depressed completely when the pulp potential is low, even at high concentrations of sodium sulfide, i.e., 10-1-10-2 mol/L. However, a partial and controlled oxida-tion of pulp does enhance the effectiveness of sodium sulfide on the depression of chalcopyrite. Characterization of the chalcopyrite particle surface by X-ray photoelectron spectroscopy allowed the identification of hydrophilic and hydrophobic surface species, which are responsi-ble for the depression and flotation of chalcopyrite. Changes in pulp potential were found to be an effective float controlling parameter, by which Na2S can be used to initiate or depress the flotation behavior of chalcopyrite.

  13. Recovery of copper ion by flotation with potassium amylxanthate; Recuperacion de iones cobre por flotacion con amilxantato de potasio

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez-Serrano, B.; Coello-Velazquez, A. L.; Bernardo, A.; Afif, E.; Menendez-Aguado, J. M.

    2012-11-01

    In this paper a study about the column flotation process of copper ion employing potassium amylxanthate as collector reagent is carried out. The effect on the recovery of copper ion by the modification of variables such as collector/metal relation and surface velocity of gas and liquid was determined experimentally by the analysis of the statistic-mathematical model of the copper flotation process, as well as the physico-chemical phenomena that take place, showing the effect of the collector/metal relation in the process. The effect of pH as the main properties of the chemical system in the recovery and the kinetic of the flotation process is made too. The experimental results shows that the recovery of copper in the pH range of 4,5 - 12 is possible with prevalence of precipitate flotation. (Author) 43 refs.

  14. Cleaner concentrates

    Energy Technology Data Exchange (ETDEWEB)

    Boudechiche, S.; Hall, S. [University of Nottingham, Nottingham (United Kingdom)

    1995-06-01

    The desire for higher quality coal products in froth flotation has led to the introduction of a number of novel flotation techniques, including flotation columns, but the benefits of each in relation to the source of the slurry must be evaluated before plant is installed. It was to assess on a laboratory scale the quality of coal flotation concentrates from column flotation of fine coal (-500{mu}m) as an alternative to the traditional conventional agitated cell that this work was carried out. The column developed specifically for this purpose allowed the establishment of an approach to the examination of the flotation response of samples of UK coals (originating from Bolsover, Derbyshies; Rawdon, Leicestershire; and Bilsthorpe, Nottinghamshire). The work indicates the importance of the origin of the feed slurry, since each type of coal exhibits a different flotation response. The observations from the results described in this paper enable an assessment to be made of the merits of column flotation in fine coal treatment. 11 refs., 4 figs., 5 tabs.

  15. Flotation Analysis for Boat Docks on U.S. Army Corps of Engineers Projects. Recreation Management Support Program

    Science.gov (United States)

    2009-06-01

    used in inexpensive “coolers” or “ice chests.” Environmental impacts associated with EPS and other plas- tics used for flotation include: the rate of...beans, and wheat. Long- term exposure to styrene can cause trouble balancing, learning impairments, fetal damage, decreased fertility in females...assessment of why encapsulation of EPS or other flotation may be environmentally beneficial is provided by Enviro -Float ( Enviro -Float Manufacturing

  16. Experimental investigation of intensification of the process of dissolved-air flotation in wastewater treatment of milk processing enterprises

    OpenAIRE

    Шевченко, Тамара Александровна; Шевченко, Андрей Александрович

    2016-01-01

    Intensification of operation of the flotation plant for wastewater treatment of dairy enterprises by applying a specially designed mixing insert (diaphragm) in the reactant treatment system is investigated. The optimum parameters of the flotation plant to achieve the required quality of wastewater treatment of dairy enterprises for discharge into the city sewer system are determined. It is found that when applying the aluminum sulfate Al2(SO4)3 coagulant, its dose is lower than that of the fe...

  17. Comparison of the egg flotation and egg candling techniques for estimating incubation day of Canada Goose nests

    Science.gov (United States)

    Reiter, M.E.; Andersen, D.E.

    2008-01-01

    Both egg flotation and egg candling have been used to estimate incubation day (often termed nest age) in nesting birds, but little is known about the relative accuracy of these two techniques. We used both egg flotation and egg candling to estimate incubation day for Canada Geese (Branta canadensis interior) nesting near Cape Churchill, Manitoba, from 2000 to 2007. We modeled variation in the difference between estimates of incubation day using each technique as a function of true incubation day, as well as, variation in error rates with each technique as a function of the true incubation day. We also evaluated the effect of error in the estimated incubation day on estimates of daily survival rate (DSR) and nest success using simulations. The mean difference between concurrent estimates of incubation day based on egg flotation minus egg candling at the same nest was 0.85 ?? 0.06 (SE) days. The positive difference in favor of egg flotation and the magnitude of the difference in estimates of incubation day did not vary as a function of true incubation day. Overall, both egg flotation and egg candling overestimated incubation day early in incubation and underestimated incubation day later in incubation. The average difference between true hatch date and estimated hatch date did not differ from zero (days) for egg flotation, but egg candling overestimated true hatch date by about 1 d (true - estimated; days). Our simulations suggested that error associated with estimating the incubation day of nests and subsequently exposure days using either egg candling or egg flotation would have minimal effects on estimates of DSR and nest success. Although egg flotation was slightly less biased, both methods provided comparable and accurate estimates of incubation day and subsequent estimates of hatch date and nest success throughout the entire incubation period. ?? 2008 Association of Field Ornithologists.

  18. Feasibility of flotation concentration of fungal spores as a method to identify toxigenic mushrooms

    Directory of Open Access Journals (Sweden)

    Bazzle LJ

    2014-12-01

    Full Text Available Lisa J Bazzle,1 Marc A Cubeta,2 Steven L Marks,1 David C Dorman3 1Department of Clinical Sciences, College of Veterinary Medicine, 2Department of Plant Pathology, College of Agriculture and Life Sciences, Center for Integrated Fungal Research, 3Department of Molecular and Biomedical Sciences, College of Veterinary Medicine, North Carolina State University, Raleigh, NC, USA Purpose: Mushroom poisoning is a recurring and challenging problem in veterinary medicine. Diagnosis of mushroom exposure in animals is hampered by the lack of rapid diagnostic tests. Our study evaluated the feasibility of using flotation concentration and microscopic evaluation of spores for mushroom identification. Evaluation of this method in living animals exposed to toxigenic mushrooms is limited by ethical constraints; therefore, we relied upon the use of an in vitro model that mimics the oral and gastric phases of digestion. Methods: In our study, mycologist-identified toxigenic (poisonous and nontoxigenic fresh mushrooms were collected in North Carolina, USA. In phase 1, quantitative spore recovery rates were determined following magnesium sulfate, modified Sheather's sugar solution, and zinc sulfate flotation (n=16 fungal species. In phase 2, mushrooms (n=40 fungal species were macerated and digested for up to 2 hours in a salivary and gastric juice simulant. The partially digested material was acid neutralized, filtered, and spores concentrated using zinc sulfate flotation followed by microscopic evaluation of spore morphology. Results: Mean spore recovery rates for the three flotation fluids ranged from 32.5% to 41.0% (P=0.82. Mean (± standard error of the mean Amanita spp. spore recovery rates were 38.1%±3.4%, 36.9%±8.6%, and 74.5%±1.6% (P=0.0012 for the magnesium sulfate, Sheather's sugar, and zinc sulfate solutions, respectively. Zinc sulfate flotation following in vitro acid digestion (phase 2 yielded spore numbers adequate for microscopic visualization in

  19. Design of gas-inducing reactors

    Energy Technology Data Exchange (ETDEWEB)

    Patwardhan, A.W.; Joshi, J.B. [Univ. of Mumbai (India). Dept. of Chemical Technology

    1999-01-01

    A gas-inducing impeller enables efficient recycling of gas from the headspace into the liquid. Historically, these impellers were used for the first time in froth flotation machines. The various designs of gas-inducing impellers (including those used in froth flotation) could be classified into three categories, depending on the flow pattern coming into and leaving the impeller zone. Correlations for the power consumption, fractional gas holdup, mass-transfer coefficient, and so forth are also available in the literature, although these studies are not comprehensive. A process design algorithm has been presented for the design of gas-inducing impellers. The algorithm consists of the determination of the rate-controlling step, selection of geometry and the operating conditions, and an economic analysis to choose the optimum design. Guidelines have been given about the desired geometry of gas-inducing impellers for achieving different design objectives such as heat transfer, mass transfer, mixing, solid suspension, froth flotation, and so forth. It has been shown that the use of a gas-inducing impeller in a conventional stirred vessel can lead to a substantial increase in the productivity. It has been shown that the optimum geometry may not correspond to the maintenance of equal power consumption per unit volume, or equal tip speed on scale-up. Suggestions have been made for future work in this area.

  20. Study of solid and liquid behavior in large copper flotation cells (130 m2 using radioactive tracers

    Directory of Open Access Journals (Sweden)

    Yianatos J.

    2013-05-01

    Full Text Available The behavior of the solid and liquid phases, in large flotation cells, was characterized by means of the radioactive tracer technique. The use of radioactive tracers enabled the identification of the Residence Time Distribution, of floatable and non-floatable solid, from continuous (on-line measuring at the output streams of the flotation cells. For this study, the proper radioactive tracers were selected and applied in order to characterize the different phases; i.e. for liquid phase Br-82 as Ammonium Bromide, for floatable solid recovered in the concentrate Cu-64, and for non-floatable solid in three particle size classes (coarse: >150 μm, intermediate: 45 μm, and fine: <45 μm, Na-24. The experimental results confirmed the strong effect of particle size on the Residence Time Distribution, and mean residence time of solids in larger flotation cells, and consequently in flotation hydrodynamics. From a hydrodynamic point of view, the experimental data confirmed that a single mechanical flotation cells, of large size, can deviate significantly from perfect mixing. The experimental work was developed in a 130 m3 industrial flotation cell of the rougher circuit at El Teniente Division, Codelco-Chile.

  1. Study of solid and liquid behavior in large copper flotation cells (130 m2) using radioactive tracers

    Science.gov (United States)

    Díaz, F.; Jiménez, O.; Yianatos, J.; Contreras, F.

    2013-05-01

    The behavior of the solid and liquid phases, in large flotation cells, was characterized by means of the radioactive tracer technique. The use of radioactive tracers enabled the identification of the Residence Time Distribution, of floatable and non-floatable solid, from continuous (on-line) measuring at the output streams of the flotation cells. For this study, the proper radioactive tracers were selected and applied in order to characterize the different phases; i.e. for liquid phase Br-82 as Ammonium Bromide, for floatable solid recovered in the concentrate Cu-64, and for non-floatable solid in three particle size classes (coarse: >150 μm, intermediate: 45 μm, and fine: flotation cells, and consequently in flotation hydrodynamics. From a hydrodynamic point of view, the experimental data confirmed that a single mechanical flotation cells, of large size, can deviate significantly from perfect mixing. The experimental work was developed in a 130 m3 industrial flotation cell of the rougher circuit at El Teniente Division, Codelco-Chile.

  2. Recovery of fine coal from waste streams using advanced column flotation. Annual report, September 1, 1990--August 31, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Groppo, J.G.

    1991-12-31

    The advanced flotation techniques, namely column flotation, have shown potential in obtaining a low ash, low pyritic sulfur fine size clean coal. The overall objective of this program is to evaluate applicability of an advanced flotation technique, `Ken-Flote` column to recover clean coal with minimum mineral matter content at greater than 90 percent combustible recovery from two Illinois preparation plant waste streams. Column flotations tests were conducted on the flotation feed obtained from the Kerr-McGee Galatia and Ziegler No. 26 plants using three different bubble-generating devices: sparger, gas saver and foam jet. Each of these devices was tested with three different frothers and various column-operating variable to provide maximum combustible recovery, minimum product ash and maximum pyrite rejection. For the Galatia slurry, the column provided a clean coal containing 5 percent ash, 0.48 percent pyritic sulfur at combustible recovery averaging 90 percent. In other words, about 90 percent ash and about 75 percent pyritic sulfur rejection were attained for the Galatia slurry. Pilot plant studies on this slurry basically obtained results similar to the laboratory studies. For the Ziegler No. 26, slurry column flotation provided a clean coal containing about 5 percent ash, 0.44 percent pyritic sulfur at more than 90 percent combustible recovery. The ash and pyrite sulfur rejection was about 85 percent and 65 percent, respectively.

  3. Headgroup interactions and ion flotation efficiency in mixtures of a chelating surfactant, different foaming agents, and divalent metal ions.

    Science.gov (United States)

    Svanedal, Ida; Boija, Susanne; Norgren, Magnus; Edlund, Håkan

    2014-06-10

    The correlation between interaction parameters and ion flotation efficiency in mixtures of chelating surfactant metal complexes and different foaming agents was investigated. We have recently shown that chelating surfactant 2-dodecyldiethylenetriaminepentaacetic acid (4-C12-DTPA) forms strong coordination complexes with divalent metal ions, and this can be utilized in ion flotation. Interaction parameters for mixed micelles and mixed monolayer formation for Mg(2+) and Ni(2+) complexes with the chelating surfactant 4-C12-DTPA and different foaming agents were calculated by Rubingh's regular solution theory. Parameters for the calculations were extracted from surface tension measurements and NMR diffusometry. The effects of metal ion coordination on the interactions between 4-C12-DTPA and the foaming agents could be linked to a previously established difference in coordination chemistry between the examined metal ions. As can be expected from mixtures of amphoteric surfactants, the interactions were strongly pH-dependent. Strong correlation was found between interaction parameter β(σ) for mixed monolayer formation and the phase-transfer efficiency of Ni(2+) complexes with 4-C12-DTPA during flotation in a customized flotation cell. In a mixture of Cu(2+) and Zn(2+), the significant difference in conditional stability constants (log K) between the metal complexes was utilized to selectively recover the metal complex with the highest log K (Cu(2+)) by ion flotation. Flotation experiments in an excess concentration of metal ions confirmed the coordination of more than one metal ion to the headgroup of 4-C12-DTPA.

  4. Use of centrifugal-gravity concentration for rejection of talc and recovery improvement in base-metal flotation

    Institute of Scientific and Technical Information of China (English)

    Bern Klein; Naci Emre Altun; Hassan Ghaffari

    2016-01-01

    The possibility of using a centrifugal-gravity concentrator to reject Mg-bearing minerals and minimize metal losses in the flotation of base metals was evaluated. Sample characterization, batch scoping tests, pilot-scale tests, and regrind-flotation tests were conducted on a Ni flotation tailings stream. Batch tests revealed that the Mg grade decreased dramatically in the concentrate products. Pilot-scale testing of a continuous centrifugal concentrator (Knelson CVD6) on the flotation tailings revealed that a concentrate with a low mass yield, low Mg con-tent, and high Ni upgrade ratio could be achieved. Under optimum conditions, a concentrate at 6.7%mass yield was obtained with 0.85%Ni grade at 12.9%Ni recovery and with a low Mg distribution (1.7%). Size partition curves demonstrated that the CVD also operated as a size classifier, enhancing the rejection of talc fines. Overall, the CVD was capable of rejecting Mg-bearing minerals. Moreover, an opportunity exists for the novel use of centrifugal-gravity concentration for scavenging flotation tailings and/or after comminution to minimize amount of Mg-bearing minerals reporting to flotation.

  5. Flotation Fault Detection and Diagnosis Method Based on Output PDF%基于输出PDF的浮选故障检测和诊断方法

    Institute of Scientific and Technical Information of China (English)

    桂卫华; 杜建江; 许灿辉; 阳春华

    2012-01-01

    计对浮选中泡沫尺寸分布的特殊性,如非高斯分布,左偏斜,高峰值等,常规分析方法无法准确描述尺寸分布的特点,因此无法准确检测和诊断浮选过程中出现的故障.提出对泡沫尺寸分布的输出概率密度函数(PDF)的统计分析,形成了一种新的浮选过程故障检测和诊断方法.通过采用自设计的核方法逼近将输出PDF转化为动态权系数,建立带有时滞的非线性不确定性权动态模型,基于线性矩阵不等式设计得到可行的故障检测和诊断算法.通过仿真验证分析,证明此算法的有效性.结合现场浮选过程,讨论了此方法的应用前景和优势.%Considering the fact that bubble size distribution in mineral flotation is found to be non-Gaussian and highly left-skewed with spike, the conventional analysis methods are unable to describe these characteristics which are significant for detecting and diagnosing process fault in flotation. It puts forward a statistical analysis on the output probability density function ( PDF) of bubble size distribution. Then a new method of fault detection and diagnosis is formed. By means of estimating the output PDF of bubble size using kernel method, the PDF is transformed into dynamic weight coefficients, based on which the uncertain nonlinear dynamic models with time delay are established. According to Linear matrix inequality (LMI) a feasible fault detection and diagnosis algorithm can be obtained. The simulation results verify the effectiveness of the proposed algorithm. With the flotation process, the prospects and advantages of this method is discussed.

  6. Varieties of conventional implicature

    Directory of Open Access Journals (Sweden)

    Eric Scott McCready

    2010-07-01

    Full Text Available This paper provides a system capable of analyzing the combinatorics of a wide range of conventionally implicated and expressive constructions in natural language via an extension of Potts's (2005 L_CI logic for supplementary conventional implicatures. In particular, the system is capable of analyzing objects of mixed conventionally implicated/expressive and at-issue type, and objects with conventionally implicated or expressive meanings which provide the main content of their utterances. The logic is applied to a range of constructions and lexical items in several languages. doi:10.3765/sp.3.8 BibTeX info

  7. Flotation behavior of four dodecyl tertiary amines as collectors of diaspore and kaolinite

    Institute of Scientific and Technical Information of China (English)

    Changmiao Liu; Feng Ansheng; GUO Zhenxu; Cao Xuefeng; Hu Yuehua

    2011-01-01

    The flotation of diaspore and kaolinite by one of a series of tertiary amines (DRN, DEN, DPN and DBN) was investigated. The tertiary amines show better floating recovery for kaolinite compared to diaspore. The maximum recovery D-value is 45% over a pH range from 3 to 8. FT-IR spectra confirm the presence of hydroxyl groups on the surface of kaolinite and diaspore. Zeta potential measurements show that the mineral surfaces are negatively charged over a wide pH range. Ionization of hydroxyl groups mainly accounts for the surface charging mechanism. The adsorption of tertiary amines onto the mineral surface is due mainly to electrostatic effects and the difference in electrostatic effect between a collector and the two minerals can explain the flotation separation. Inductive electronic and steric effects from the substituent groups result in different collecting powers for the four tertiary amines.

  8. Removal of flotation reagents from process water by adsorption onto spent zeolite catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, J.F.; Valdiviezo, E. [COPPE/UFRJ, Rio de Janeiro (Brazil). Dept. of Materials and Metallurgical Engineering]|[CETEM/CNPQ, Rio de Janeiro (Brazil). Center for Mineral Technology

    1995-12-31

    Adsorption of residual flotation reagents onto equilibrium fluid cracking catalysts is a promising method of purification of flotation process water. In the present paper, adsorption of sodium dodecyl sulfate (SDS), dodecyl ammonium chloride (DAC) and sodium oleate onto a spent catalyst from petroleum industry was studied by analyzing the residual concentration of the surfactant after contact with the zeolite catalyst. The adsorption of the DAC was rather low but SDS and sodium oleate presented a high affinity for the catalyst surface. The loading capacity was 4.2 kg/ton for SDS and 5.5 kg/ton for oleic acid. After the treatment of the loaded catalyst with a HCl 1N solution these surfactants are desorbed and the catalyst may thus be regenerated. This would be an additional advantage to its low cost, not to mention its condition as a discarded product and its availability in large tonnages.

  9. Effective harvesting of the microalgae Chlorella vulgaris via flocculation-flotation with bioflocculant.

    Science.gov (United States)

    Lei, Xueqian; Chen, Yao; Shao, Zongze; Chen, Zhangran; Li, Yi; Zhu, Hong; Zhang, Jingyan; Zheng, Wei; Zheng, Tianling

    2015-12-01

    In this study, bioflocculant from Cobetia marina L03 could be used for effective harvesting of the microalgae Chlorella vulgaris via flocculation-flotation. A flotation efficiency of 92.7% was observed when 20 mg L(-1) bioflocculant was tested for flocculating the microalgal cells with 5mM CaCl2. The bioflocculant was stable at wide ranges of pH and temperature, which is advantageous for its application under various conditions. Chemical analysis of the bioflocculant indicated that it is composed of 31.6% total sugar and 0.2% protein (w/w). This bioflocculant has potential for the high-efficiency harvesting of microalgae and may be useful in reducing one of the barriers to microalgal biofuel production.

  10. Flotation of zinc and lead oxide minerals from Olkusz region calamine ores

    Directory of Open Access Journals (Sweden)

    Cichy Krystian

    2016-01-01

    Full Text Available The paper presents chemical and mineralogical characteristics of calamine ore from the Pomorzany mine. A flowsheet for recovery of sulphide minerals of zinc and lead in the form of the Zn-Pb bulk concentrate was presented. In the following part, preparation of the feed for flotation of Zn-Pb oxide minerals and optimal conditions for separation from it iron sulphide minerals, represented by marcasite, were determined. In the final section the results of flotation of Zn-Pb oxide minerals with anionic collector AM2 belonging to the hydroxyamide group of collectors and a cationic collector in the form of a coconut amine, being a mixture of primary aliphatic amines, were presented. Basing on the obtained results, a technological flowsheet for the recovery of Zn-Pb sulphide and oxide minerals from the calamine ore of the Pomorzany mine was presented.

  11. Utilization of polysaccharides as depressants for the flotation separation of copper/lead concentrate

    Institute of Scientific and Technical Information of China (English)

    Qin Wenqing; Wei Qian; Jiao Fen; Yang Congren; Liu Ruizeng; Wang Peipei; Ke Lifang

    2013-01-01

    The interaction mechanism between dextrin and minerals has been investigated through micro-flotation,adsorption density measurements,Fourier transform infrared ray (FTIR) spectroscopic studies and dissolution tests.Dextrin shows a good depressing action towards galena but not chaicopyrite.FTIR spectroscopic studies indicate that dextrin chemically adsorbed on galena surface in alkaline pH range.Dissolution tests confirm leaching action of metal ions from chalcopytite and galena surfaces,and dextrin-lead ion interaction.Adsorption measurements present that the higher adsorption density of O-isopropyl-N-ethyl thionocarbamate (IPETC) onto chalcopyrite than that onto galena,and IPETC adsorbed on galena decrease with increasing dextrin concentrations in the presence of dextrin,attesting the flotation results.

  12. Flotation de-silicating from diasporic-bauxite with cetyl trimethylammonium bromide

    Institute of Scientific and Technical Information of China (English)

    王毓华; 胡岳华; 刘晓文

    2003-01-01

    Using cetyl trimethylammonium bromide (CTAB) as collector, the flotation de-silicating from diasporicbauxite was investigated. And the Zeta potentials and contact-angles of silicate minerals and diaspore were also stuite and illite become more positive, and the contact angles of these three silicates also increase evidently in the pH range of 2-8, but the Zeta potentials and contact angles of diaspore change little. So, the floatability of the four minerals is in the following order: pyrophyllite>kaolinite≈illite>diaspore. The open-circuit flotation results also show that a bauxite concentrate with m(Al2 O3 )/m(SiO2 ) over 9.3 and Al2 O3 recovery over 76% can be obtained from diasporic-bauxite ore. The result of XRD of the bauxite concentrate shows that pyrophyllite is easier to be removed from diasporic-bauxite than illite and kaolinite due to its better floatability.

  13. Recovery of Mercury and Lead from Wastewater by Sulfide Precipitation-Flotation

    Science.gov (United States)

    Li, Qian; Liu, Ting; Deng, Peng

    The wastewater containing Hg2+ and Pb2+ does great harm to the environment and human bodies. Traditional wastewater treatment cannot fundamentally put a stop to heavy metals pollution for producing secondary pollution. In this paper, Hg2+ and Pb2+ in wastewater were removed and recovered by sulfide precipitation-flotation. Sodium sulfide was used as precipitant and butyl ammonium aero float was used as collector. Results indicated that Hg2+ and Pb2+ could be reduce to less than 0.03mg/L and 0.16mg/L respectively by both coprecipitation-floatation and fractional precipitation-floatation. In these two methods, fractional precipitation flotation could not only remove Hg2+ and Pb2+ from wastewater, but also could recover mercury and lead effectively. The infrared spectrograms showed that the adsorption between butyl ammonium aerofloat and mercury precipitate or lead precipitate is chemisorption.

  14. Comparison of coagulants and coagulation aids for treatment of meat processing wastewater by column flotation.

    Science.gov (United States)

    de Sena, Rênnio F; Moreira, Regina F P M; José, Humberto J

    2008-11-01

    The physicochemical treatment of the wastewater from a meat processing industry was studied using three ferric salts as coagulants in conjunction with four different polymers as coagulation aids by batch column flotation. The effluent was characterized in terms of pH (6.5-6.7), turbidity (1000-12000 NTU), total solids (TS) (2300-7000mgl(-1)), oils and greases (OG) (820-1050mgl(-1)), and biochemical and chemical oxygen demands (BOD(5) and COD) (1200-1760 and 2800-3230mgl(-1)), respectively. The treatments achieved typical organic load reductions of oils and greases, and total solids (up to 85%), as well as biochemical and chemical oxygen demands (between 62.0-78.8% and 74.6-79.5%, respectively). The research also found that the utilization of a column flotation achieved high efficiency of organic matter removal and its operation as a primary treatment showed no significant dependence of pollutant removal and air flow rate.

  15. Treatment of Wastewater Containing Heavy Metals Using Dissolved Air Released Flotation Column

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A new type of dissolved air released flotation column is developed to treat wastewater containing Cr(Ⅵ) based on advantages of both dissolved air floatation and column floatation. By using a column with a diameter of 50 mm and a specially made dissolved air releaser, micro-bubbles inside the column can be formed. N2H4.H2O was used as reductant, AlCl3 as flocculant, C12H25SO3Na(SDS) as surfactant in the experiment. The effects of pH of wastewater, pressure of dissolved air, ratio of return water, and concentration of flocculant and surfactant on the removal efficiency are studied. The results show that the efficiency of dissolved air released flotation column is much higher than that of other approaches after the operation parameters are optimized, with the reduction ratio of Cr(Ⅵ) in wastewater reaching 98%. So this technique can be widely used in wastewater treatment.

  16. Evaluation of sorptive flotation technique for enhanced removal of radioactive Eu(III) from aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Ezzat, Amir; Saad, Ebtissam A. [Ain Shams Univ., Cairo (Egypt). Chemistry Dept.; Mahmoud, Mamdoh R. [Atomic Energy Authority, Cairo (Egypt). Nuclear Chemistry Dept.; Soliman, Mohamed A. [Atomic Energy Authority, Cairo (Egypt). Egypt Second Research Reactor; Kandil, Abdelhakim [Helwan Univ., Cairo (Egypt). Chemistry Dept.

    2017-06-01

    The present study aims at the removal of Eu(III) from aqueous solutions by sorptive flotation process. This process involves adsorption of Eu(III) onto bentonite and kaolinite clays followed by floatation using sodium dodecyl sulfate (SDS) and cetyltrimethylammonium bromide (CTAB) collectors. The effect of adsorption parameters (pH, contact time, clay weight, Eu(III) concentration, ionic strength) as well as flotation parameters (collector and frother concentrations, bubbling time, concentrations of foreign cations and anions) on the removal efficiency of Eu(III) were studied. The obtained results show that Eu(III) ions are removed efficiently (R% ∝ 95%) at pH=4 after 1 h shaking with clay and 15 min floatation. The adsorption kinetics of Eu(III) onto the employed clays followed the pseudo-second-order model and the equilibrium data fitted well to the Freundlich isotherm model.

  17. Evaluating the efficacy of a centrifugation-flotation method for extracting Ascaris ova from soil

    DEFF Research Database (Denmark)

    Cranston, Imogen; Teoh, Penelope J.; baker, Sarah M.

    2016-01-01

    and flotation technique was applied to 15 soil types, which were seeded with Ascaris suum ova. Soil type, soil moisture content, soil texture and organic matter content were assessed for each soil sample. Results: The average ova recovery rate was 28.2%, with the recovery rate of the method decreasing...... with increasing soil moisture content, particle size and organic matter content. The association between recovery rate and organic matter content was statistically significant. Conclusions: The present study identified a low recovery rate for an adapted centrifugation-flotation method, although this was similar...... to the recovery rate demonstrated by other methods developed for soil. Soil organic matter content was significantly associated with ova recovery rates...

  18. Flotation of quartz using N- (2-aminoethyl)-octadecanamide as collector

    Institute of Scientific and Technical Information of China (English)

    赵世民

    2003-01-01

    The flotation behavior of quartz using N-(2-aminoethyl)-octadecanamide (AEOA) as a collector was investigated. Zeta potential and infrared spectra were conducted to investigate the mechanism of the interaction of the quartz surface with the collector molecules. The results show that electrostatic force and hydrogen bond play an important role in governing the mechanism of flotation in acidic and alkaline media. The recoveries of quartz are 99.0%-99.8% in the pH range of 3-11. The recovery of quartz is less dependent on AEOA concentration, mainly due to the formation of micellae in aqueous solution,and the adsorption density of AEOA on the quartz surface nearly remains constant.

  19. EXPERIMENTAL STUDY OF DESULFURIZATION OF ZHONG LIANG SHAN HIGH SULFUR COAL BY FLOTATION

    Institute of Scientific and Technical Information of China (English)

    姜志伟; 黄波; 曹炅

    1994-01-01

    Emission of large amount of SO2 from combustion of high sulfur coal causes serious envjsonmental pollution. Pre-combustion desulfurization of bigh sulfur coal has become a necessity. This paper reports test results of fine coal desuifurtzation with different flotation technology and the effect of pyrite depressant. Test work showed that when the coal sample from Zhong Liang Shah was processed with a Free Jet Flotation Column its pyritic sultur content was reduced from 3.08% to 0. 84%, with 72.22% recovery ofcombustible matter in clean coal. The concept of Desulfurlzatlon Efficiency Index Eofor comprehensive evaluation of dcsuifurlzation process is proposed, which is defined as the product of the ratio of sulfur content reduction of clean coal and the recovery of combustible matters.

  20. Galvanic coupling and its effect on origin potential flotation system of sulfide minerals

    Institute of Scientific and Technical Information of China (English)

    顾帼华; 戴晶平; 王晖; 邱冠周

    2004-01-01

    The galvanic coupling formed in origin potential flotation systems of sulfide minerals can be divided into three types: sulfide mineral-sulfide mineral-water system; sulfide mineral-steel ball-water system; and sulfide mineral-sulfide mineral-collector system. In this paper, taking lead, zinc, iron sulfide mineral systems for examples,several models of galvanic coupling were proposed and the effects of galvanic coupling on flotation were discussed. A galvanic contact between galena (or sphalerite) and pyrite contributes to decreasing the content of zinc in lead concentrate, and enhances remarkably the absorption of collector on the galena surface. During grinding, due to galvanic interactions between minerals and steel medium, Fe(OH)3 formed covers on the cathodic mineral surface, affecting its floatability.

  1. A study on the effects of ozone dosage on dissolved-ozone flotation (DOF) process performance.

    Science.gov (United States)

    Jin, Xin; Jin, Pengkang; Wang, Xiaochang

    2015-01-01

    Dissolved-ozone flotation (DOF) is a tertiary wastewater treatment process, which combines ozonation and flotation. In this paper, a pilot-scale DOF system fed by secondary effluent from a wastewater treatment plant (WWTP) in China was used to study the effect of ozone dosage on the DOF process performance. The results show that an ozone dosage could affect the DOF performance to a large extent in terms of color and organic matter removal as well as disinfection performance. The optimal color and organic matter removal was achieved at an ozone dosage of 0.8 mg/l. For disinfection, significant improvement in performance could be achieved only when the organic matter removal was optimal. The optimal ozone dosage of at least 1.6 mg/l was put forward, in this case, in order to achieve the optimal color, turbidity, organic matter and disinfection performance.

  2. Flotation of high-grade fluorite in a short column under negative bias regime

    OpenAIRE

    2006-01-01

    RESTRITO This paper presents flotation results carried out on fluorite ore using a relatively short column, operated under negative bias regime and without wash water. The term short column is used from a kinetic point of view from which collection zone comes out to be around 8 m tall (the relation height/diameter appears valid for industrial size columns). Negative bias was achieved making tailing flow smaller than feed flow. Hence, part of the water is carried up within bubbles wakes. No...

  3. Redesign of Industrial Column Flotation Circuits Based on a Simple Residence Time Distribution Model

    OpenAIRE

    2008-01-01

    The potential for improved selectivity has made column flotation cells a popular choice for upgrading fine coal. Unfortunately, recent production data from full-scale column plants indicate that many industrial installations have failed to meet original expectations in terms of clean coal recovery. Theoretical studies performed using a simple dispersion model showed that this inherent shortcoming could be largely minimized by reconfiguring the columns to operate in series as a cell-to-cell ci...

  4. Some aspects of using ultrasounds to improve sulfurous mineral flotation technology

    Science.gov (United States)

    Mihu, V. P.; Pop, I.

    1974-01-01

    The results are discussed which were obtained with a new method of desorption of collector reagents connected with improving the selectivity of the flotation of copper and lead concentrate through the action of ultrasounds. Analysis of the results obtained by treating copper and lead concentrate in an ultraacoustic field indicates an increase in the copper content of the copper concentrate, of the lead content in the lead concentrate and, at the same time, a reduction in the lead of the copper concentrate.

  5. The removal of heavy metals from contaminated soil by a combination of sulfidisation and flotation.

    Science.gov (United States)

    Vanthuyne, Mathias; Maes, André

    2002-05-06

    The possibility of removing cadmium, copper, lead and zinc from Belgian loamy soil by a combination of sulfidisation pre-treatment and Denver flotation was investigated. The potentially available--sulfide convertible--metal content of the metal polluted soil was estimated by EDTA (0.1 M, pH 4.65) extraction and BCR sequential extraction. EDTA extraction is better at approximating the metal percentage that is expected to be convertible into a metal sulfide phase, in contrast to the sequential extraction procedure of 'Int. J. Environ. Anal. Chem. 51 (1993) pp. 135-151' in which transition metals present as iron oxide co-precipitates are dissolved by hydroxylammoniumchloride in the second extraction step. To compare the surface characteristics of metal sulfides formed by sulfidisation with those of crystalline metal sulfides, two types of synthetic sediments were prepared and extracted with 0.1 M EDTA (pH 4.65) in anoxic conditions. Separate metal sulfides or co-precipitates with iron sulfide were formed by sulfide conditioning. The Denver flotation of both types of synthetic sediments (kerosene as collector at high background electrolyte concentrations) resulted in similar concentrating factors for freshly formed metal sulfides as for fine-grained crystalline metal sulfides. The selective flotation of metal sulfides after sulfide conditioning of a polluted soil, using kerosene or potassium ethyl xanthate as collectors and MIBC as frother, was studied at high background electrolyte concentrations. The sulfidisations were made in ambient air and inside an anoxic glove box. The concentrating factors corrected by the potentially available metal percentage, determined by 0.1 M EDTA extraction, lie between 2 and 3. The selective flotation of these finely dispersed, amorphous, metal sulfides can possibly be improved by optimising the bubble-particle interaction.

  6. Column flotation monitoring based on electrical capacitance volume tomography: A preliminary study

    Science.gov (United States)

    Haryono, Didied; Harjanto, Sri; Nugraha, Harisma; Huda, Mahfudz Al; Taruno, Warsito Purwo

    2017-01-01

    A preliminary study of column flotation monitoring process using electrical capacitance volume tomography (ECVT) was conducted. ECVT was one of the monitoring systems which based on the capacitance measurement. It was used to understand the phenomenon that occurs inside the column in a three-dimensional (3-D) image. A linear back projection (LBP) algorithm technique was used to reconstruct the 3-D ECVT images from all measurement data obtained in this study. As a preliminary study, the effect of gas injection in the two-phase (liquid and gas) system was conducted. This study is conducted to assess the possibility of ECVT system in the monitoring of column flotation process. The experiments were conducted by using column flotation with 5 cm diameter and 150 cm height in which a sparger was installed at the bottom of column to inject air inside the column. 32-CH rectangular ECVT sensor was installed at 13 cm above the sparger and placed around the column. The gas injection variations used were 2-7 l/min with interval 1 l/min and all experiments were conducted at room temperature. Based on the signal and image analysis, the signals and 3-D ECVT images showed differences when the gas injection was varied. An increase in gas injection will decrease the fluctuation of signal intensity which correlates to the 3-D ECVT images. Average signals obtained by ECVT when given gas injection variations were in the range of 440.09 to 453.62 mV from high to low gas injection. Based on these results, ECVT has a prospect as an imaging tool to monitor the column flotation process. And also, hopefully, based on the analysis of 3-D images generated by ECVT system, the metallurgical performance would be analyzed in the further researches.

  7. Use of coagulants in treatment of olive oil wastewater model solutions by induced air flotation.

    Science.gov (United States)

    Meyssami, B; Kasaeian, A B

    2005-02-01

    Natural polyelectrolytes are suitable coagulants for the treatment of industrial and minicipal wastewaters because they are safe and have environmental benefits. Chitosan, a natural cationic polyelectrolyte, and other similar coagulants were used in the treatment of an olive oil water suspension as a model for the processing wastewater. The effect of chitosan, starch, alum and ferric chloride on the coagulation of oil droplets were determined by the jar test apparatus and turbidometric measurements. Olive oil emulsion samples were prepared by the use of surface active agents and other agents that could form stable oil water emulsions. The effect of parameters such as pH, ionic strength and optimum dosage of the coagulants were determined in the jar test experiments. Following the jar experiments, with the optimum concentration of the suitable coagulant, the emulsions were placed in an induced air flotation (IAF) cell to separate the coagulated oil droplets from solution. In the air flotation experiments, the effect of temperature, surfactant concentration and air flowrate were determined on the decrease of turbidity and COD of the emulsion samples. In the jar experiments, chitosan and alum used together at concentrations of 15 and 25 ppm, respectively, at pH 6 produced the lowest turbidity values. In the air flotation experiments, a concentration of 100 ppm of chitosan, an air flowrate of 3 l/min, aeration time of 45 s, temperature of 20 degrees C and pH 6 produced optimum levels. At optimum conditions of coagulation and flotation stages, the COD of the olive oil emulsion could be reduced by 95%.

  8. Wastewater treatment using flocculation, coagulation, and flotation. (Latest citations from the NTIS bibliographic database). Published Search

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-11-01

    The bibliography contains citations concerning the design, development, and evaluation of flocculation coagulation and flotation processes for the treatment of sewage and industrial wastes. Citations examine technology requirements and limitations, activated sludge and anaerobic processes, chlorination, runoff pollution control, wastewater recycling and reuse, and materials recovery.(Contains 50-250 citations and includes a subject term index and title list.) (Copyright NERAC, Inc. 1995)

  9. The first case of Demodex gatoi in Austria, detected with fecal flotation.

    Science.gov (United States)

    Silbermayr, Katja; Joachim, Anja; Litschauer, Barbara; Panakova, Lucia; Sastre, Natalia; Ferrer, Lluis; Horvath-Ungerboeck, Christa

    2013-08-01

    Feline demodicosis is a rare parasitic condition caused by three different species of mites (Demodex cati, Demodex gatoi, and an unnamed species). D. gatoi inhabits the superficial skin layer (stratum corneum) and is easily transmitted between individual cats. A 2-year-old female spayed Cornish Rex was presented with alopecia and pruritus. The dermatological examination revealed bilateral alopecia and excoriations on trunk, limbs, and belly. The second cat in the household, a 3-year-old female spayed Thai, showed no clinical signs. Superficial and deep skin scrapings were performed and cellophane tapes applied, and living D. gatoi mites could be detected in both cats. Oral ivermectin (0.25 mg/kg every other day) was subscribed. Feces were collected from both cats and fecal flotation with sugar and zinc solutions performed. When compared to skin scrapings and cellophane tapes, D. gatoi was detected more frequently and in higher numbers in fecal samples. Our findings suggest that D. gatoi can be efficiently diagnosed with coproscopy, particularly in asymptomatic carrier animals. DNA was extracted from the flotation liquid, and a PCR protocol for the species verification was designed. A fragment targeting a 325-bp DNA fragment of the D. gatoi mitochondrial 16S rDNA gene was amplified with a 100% similarity to the D. gatoi entry in GenBank® (GI 421920216). We report the first finding of D. gatoi in Austria and propose fecal flotation as a valuable tool for mite detection. Fecal flotation liquid is suitable for DNA extraction and PCR-based species verification of D. gatoi.

  10. Flotation of cobalt bearing minerals from a mixed copper-cobalt oxidized ore

    OpenAIRE

    2012-01-01

    M.Tech. (Extraction Metallurgy) The techniques for the flotation of mixed copper and cobalt bearing oxide ores using the sulphidization method in order to recover the oxidized copper and cobalt bearing minerals have been well documented by previous researchers. These processes have been successfully implemented in many of the metallurgical plant operations in the Democratic Republic of Congo (DRC). The mixed copper and cobalt oxidised ores from this region present significant chal-lenges t...

  11. Depressing effect of sodium hexametaphosphate on apatite in flotation of rutile

    Institute of Scientific and Technical Information of China (English)

    Hao Ding; Hai Lin; Yanxi Deng

    2007-01-01

    The separation of mtile from apatite by flotation and the mechanism of depressing the apatite of sodium hexametaphosphate were studied. The results showed that rutile and apatite could be separated by using alkyl-imino-bismethylene phosphoric acid and sodium hexametaphosphate as a collector and a regulator, respectively. Sodium hexametaphosphate could selectively dissolve calcium ions on the apatite surface, and make calcium ions break away from lattice binding through combining.

  12. Selective factors involved in oil flotation isolation of black yeasts from the environment

    OpenAIRE

    Satow, M.M.; Attili-Angelis, D. [UNESP; de Hoog, G. S.; Angelis, D. F. [UNESP; Vicente, V.A.

    2008-01-01

    The oil flotation isolation technique has been successfully applied to recover chaetothyrialean black yeasts and relatives from the environment. The selective mechanisms playing a role in isolation are unknown. The fungi concerned are supposed to occupy specialized microniches in nature, taking advantage of (1) oligotrophism. Mineral oil as a main selective agent may be based on (2) hydrophobicity or on (3) assimilation. All three hypotheses are tested in this paper. Results show that cell wa...

  13. Optimization of Dissolved Air Flotation for Algal Harvesting at the Logan, Utah Wastewater Treatment Plant

    OpenAIRE

    Elder, Andrew R.

    2011-01-01

    This research evaluated dissolved air flotation (DAF) as a separation method for algae and phosphorus from municipal wastewater at the City of Logan, Utah Wastewater Reclamation Facility. DAF uses the supersaturation of air to raise suspended algae and other particles to the surface, where they can be easily removed. DAF, in conjunction with chemical coagulants and flocculants, can approach 95% algae and phosphorus removal. The algae removed using the DAF process will be used in the productio...

  14. Extraction and Separation of Molybdenum by Using Homogeneous Liquid-Liquid Microextraction via Flotation Assistance

    OpenAIRE

    Rezaee, Mohammad; Mozaffari,Maryam; Haddadi,Hedayat; Pourjavid,Mohammad R.; SEMNANI, Abolfazl

    2015-01-01

    Homogeneous liquid-liquid microextraction via flotation assistance (HLLME-FA) was investigated for the extraction of molybdenum from the water samples. Alizarin Red S and cetyl trimethylammonium bromide (CTAB) were used as a complexing ligand and ion-pairing reagent, respectively. The enriched analyte in the floated organic phase was determined by electrothermal atomic absorption spectrometry (ETAAS). In this work, low density organic solvent was used and no centrifugation was required in thi...

  15. Oxidative Pressure Leaching of Silver from Flotation Concentrates with Ammonium Thiocyanate Solution

    Science.gov (United States)

    Yang, Sheng-Hai; Yang, Jian-Guang; Liu, Wei; Chen, Geng-Tao; Tang, Mo-Tang; Qiu, Guan-Zhou

    2010-02-01

    The thermodynamics and technologies of the selective pressure leaching of silver from flotation concentrates were investigated in an ammonium thiocyanate medium. Thermodynamic analyses, which include silver solubility in NH4SCN solution and Eh-pH diagrams of the Me-MeS-NH4SCN-H2O system at 25 °C, were discussed. The effects of several factors, such as temperature, leaching time, oxidant, pH value, flotation concentrates concentration, surfactant concentration, and so on, on the extraction percentages of silver and zinc were investigated. The following optimal leaching conditions were obtained: NH4SCN concentration 1.5 M, lignin concentration 0.5 g/L, Fe3+ concentration 2 g/L, flotation concentrates addition 200 g/L, and oxygen pressure 1.2 MPa at 130 °C for 3 hours. Under these optimum conditions, the average extraction percentage of silver exceeded 94 pct, whereas the average extraction percentage of zinc was less than 3 pct. Only 7 pct of ammonium thiocyanate was consumed after 4 cycles, which indicated that ammonium thiocyanate hardly was oxidized under these oxidative pressure leaching conditions.

  16. Investigation of the possibility of copper recovery from the flotation tailings by acid leaching.

    Science.gov (United States)

    Antonijević, M M; Dimitrijević, M D; Stevanović, Z O; Serbula, S M; Bogdanovic, G D

    2008-10-01

    The flotation tailings pond of the Bor Copper Mine poses a great ecological problem not only for the town of Bor but also for the surrounding soils and watercourses. Since the old flotation tailings contain about 0.2% of copper on the average, we investigated their leaching with sulphuric acid in the absence and presence of an oxidant. The aim was to determine the leaching kinetics of copper and iron as affected by various factors such as: the pH value of the leach solution, stirring speed, pulp density, particle size, concentration of ferric ions, temperature and time for leaching. The average copper and iron recovery obtained was from 60% to 70% and from 2% to 3%, respectively. These results indicate that the old flotation tailings pond represents an important source of secondary raw material for the extraction of copper and that it should be valorized rather than land reclamation. At the end of the paper, a mechanism of dissolution of copper and iron minerals from the tailings was described.

  17. Bioleaching of copper from old flotation tailings samples (Copper Mine Bor, Serbia

    Directory of Open Access Journals (Sweden)

    Stanković Srđan

    2015-01-01

    Full Text Available Bioleaching of samples taken from depths of 10, 15, and 20 meters from old flotation tailings of the Copper Mine Bor was conducted in shaken flasks using extremely acidic water of Lake Robuleas lixiviant. Yield of copper after five weeks of the bioleaching experiment was 68.34±1.21% for 15 m sample, 72.57±0.57% for 20 m sample and 97.78±5.50% for 10 m sample. The obtained results were compared to the results of acid leaching of the same samples and it was concluded that bioleaching was generally more efficient for the treatment of samples taken from depths of 10 m and 20 m. The content of pyrite in the 20 m sample, which contained the highest amount of this mineral, was reduced after bioleaching. Benefits of this approach are: recovery of substantial amounts of copper, reducing the environmental impact of flotation tailings and the application of abundant and free water from the Robule acidic lake as lixiviant. Results of the experiment showed that bioleaching can be more efficient than acid leaching for copper extraction from flotation tailings with higher sulfide contents. [Projekat Ministarstva nauke Republike Srbije, br. 176016 i br. 173048

  18. Enhanced sulfidation xanthate flotation of malachite using ammonium ions as activator.

    Science.gov (United States)

    Wu, Dandan; Ma, Wenhui; Mao, Yingbo; Deng, Jiushuai; Wen, Shuming

    2017-05-18

    In this study, ammonium ion was used to enhance the sulfidation flotation of malachite. The effect of ammonium ion on the sulfidation flotation of malachite was investigated using microflotation test, inductively coupled plasma (ICP) analysis, zeta potential measurements, and scanning electron microscope analysis (SEM). The results of microflotation test show that the addition of sodium sulfide and ammonium sulfate resulted in better sulfidation than the addition of sodium sulfide alone. The results of ICP analysis indicate that the dissolution of enhanced sulfurized malachite surface is significantly decreased. Zeta potential measurements indicate that a smaller isoelectric point value and a large number of copper-sulfide films formed on the malachite surface by enhancing sulfidation resulted in a large amount of sodium butyl xanthate absorbed onto the enhanced sulfurized malachite surface. EDS semi-quantitative analysis and XPS analysis show that malachite was easily sulfurized by sodium sulfide with ammonium ion. These results show that the addition of ammonium ion plays a significant role in the sulfidation of malachite and results in improved flotation performance.

  19. Hybrid flotation--membrane filtration process for the removal of heavy metal ions from wastewater.

    Science.gov (United States)

    Blöcher, C; Dorda, J; Mavrov, V; Chmiel, H; Lazaridis, N K; Matis, K A

    2003-09-01

    A promising process for the removal of heavy metal ions from aqueous solutions involves bonding the metals firstly to a special bonding agent and then separating the loaded bonding agents from the wastewater stream by separation processes. For the separation stage, a new hybrid process of flotation and membrane separation has been developed in this work by integrating specially designed submerged microfiltration modules directly into a flotation reactor. This made it possible to combine the advantages of both flotation and membrane separation while overcoming the limitations. The feasibility of this hybrid process was proven using powdered synthetic zeolites as bonding agents. Stable fluxes of up to 80l m(-2)h(-1) were achieved with the ceramic flat-sheet multi-channel membranes applied at low transmembrane pressure (copper, nickel and zinc, were reduced from initial concentrations of 474, 3.3 and 167mg x l(-1), respectively, to below 0.05 mg x l(-1), consistently meeting the discharge limits.

  20. The Adsorption of Cu Species onto Pyrite Surface and Its Effect on Pyrite Flotation

    Directory of Open Access Journals (Sweden)

    Bo Yang

    2016-01-01

    Full Text Available The adsorption of Cu species onto pyrite surface and its effect on flotation were investigated by using microflotation tests, first-principle calculations, and XPS surface analysis. The results indicated that the flotation of pyrite appears to be activated with CuSO4 only at alkaline pH, while being depressed at acidic and neutral pH. The adsorption of copper ions on pyrite surface was pH-dependent, and the adsorption magnitude of copper ions at alkaline pH is higher than that at acidic and neutral pH due to a strong interaction between O atom in Cu(OH2 and surface Fe atom except for the interaction between Cu atom and surface S atom. At acidic and neutral pH, there is only an interaction between Cu atom and surface S atom. The adsorption was relatively weak, and more copper ions in solution precipitated the collector and depressed the flotation of pyrite. XPS analysis confirmed that more copper ionic species (Cu(I and Cu(II are adsorbed on the pyrite surface at alkaline pH than that at acidic and neutral pH.

  1. Indirect determination of thiocyanate with ammonium sulfate and ethanol by extraction-flotation of copper.

    Science.gov (United States)

    Li, Q; Wei, W; Liu, Q

    2000-10-01

    A new method for the indirect determination of thiocyanate with ammonium sulfate and ethanol by extraction-flotation of copper in the presence of ascorbic acid is described. A small amount of Cu(II) is reduced to Cu(I) by ascorbic acid, then Cu(I) is precipitated with SCN-. In the course of phase separation of ethanol from water, the precipitated CuSCN stays in the interface of ethanol and water. A good linear relationship is observed between the flotation yield of Cu(II) and the amount of SCN-. Using 1.0 ml of 1 x 10(-3) M ascorbic acid solution, 50 micrograms of Cu(II), 3.5 g of (NH4)2SO4 and 3.0 ml of ethanol with a total volume of 10 ml, the concentration of thiocyanate could then be determined by determining the flotation yield of Cu(II). The detection limit for thiocyanate is 5 x 10(-5) M. Every parameter was optimized and the reaction mechanism was studied. The method is simple and rapid and it was successfully applied to the determination of thiocyanate in urine and saliva of smokers and non-smokers and in venous blood of patients infused with sodium nitroprusside.

  2. Determination and evaluation of the results of fine slimes flotation under modern pulp flowsheet conditions

    Energy Technology Data Exchange (ETDEWEB)

    Antipenko, L.; Kravchenko, L.; Oparin, L.; Syvorotkin, A. [Sibniiugleobogashcheniya (Russian Federation)

    1998-12-31

    This paper concerns a study of the influence of metamorphism on coal slurry particle size composition. Kuznetsk basin coal (0.2 to 0.5 mm) was determined to be of low ash content, i.e. there was no need to process this coal. The relation of the size fraction 0.2 to 0.5 mm content to vitrinite content and to the degree of metamorphism has been estimated. On the basis of genetic characteristics and adsorption capacity of coal, the effect of size classification and separate pulp conditioning on the flotation of 0 to 0.5 mm coal is suggested. Floatability of size factions 0 to 0.5 mm and 0 to 0.1 mm was investigated. The imperfection coefficient of the laboratory flotation machine is 0.35 to 0.4. Separation efficiency (Ep) is 1.1 for coal slurry (0 to 0.5 mm) with a high degree of metamorphism and is 1.3 for the 0 to 0.2 mm size fraction. When floating the size fraction 0 to 0.1 mm the Ep is 1.5 to 1.7 for both low and high degrees of metamorphism. It is recommended that flotation machines of a pneumo-mechanical type be used for processing 0 to 0.2 mm coal. Three versions of possible pulp flowsheets are presented in this paper. 3 figs., 2 tabs.

  3. An Investigation of Reverse Flotation Separation of Sericite from Graphite by Using a Surfactant: MF

    Directory of Open Access Journals (Sweden)

    Yangshuai Qiu

    2016-06-01

    Full Text Available In this paper, a surfactant, atlox4862 (formaldehyde condensate of methyl naphthalene sulfonic sodium salt (MF, was introduced as a depressant for reverse flotation separation of sericite from graphite. Natural flake graphite has a strong hydrophobic property. After interacting with MF, the graphite became moderately hydrophilic. The flotation results showed that MF had a depressing ability for both sericite and graphite and that the flotation separation of sericite from graphite was attributed to the different declining levels of recovery between graphite and sericite with increased MF concentration. For a pulp pH of 8 and a MF concentration of 250 mg/L, the recovery rates of sericite and graphite were 89.7% and 11.3%, respectively. The results of the FTIR spectra and zeta potential measurements demonstrated that the interaction of MF with graphite and sericite is mainly through electrostatic attraction. MF was preferred to adsorb on the surface of graphite, decreasing its zeta potential and improving its hydrophilicity more than that of sericite.

  4. Fine coal flotation plant waste comparison--column vs. sub-a cells

    Energy Technology Data Exchange (ETDEWEB)

    Ehrlinger, H.P. III.

    1991-01-01

    The objective of this project was to compare results from a small commercially sized Deister Flotaire column flotation cell with the subaeration cells at Kerr-McGee's Galatia plant during side by side testing of feed splits from the same sources. Typical cell criteria for both cells are included in the appendix. The project involved the activities of three organizations: the Kerr-McGee Coal Corporation, the Deister Concentrator Company, and the Illinois State Geological Survey. Their roles were as follows: Kerr-McGee installed the Deister column with sample splitter and tailings volume measuring cell in the Galatia Coal Preparation Plant to treat a representative split of their flotation feed; Deister provided a 30 inch diameter {times} 35{prime} high Deister Flotaire Column Flotation Cell capable of treating nominally one ton per hour or slightly over 1% of the plant feed. Deister additionally provided the sample splitter and the tailings volume measuring cell. ISGS personnel worked with both companies on the installation, conducted laboratory tests to direct the early plant test reagent practice, attended all of the plant runs cutting representative samples of feed, measuring slurry and reagent flows, preparing samples and writing reports.

  5. A new synthetic chelating collector for the flotation of oxidized-lead mineral

    Institute of Scientific and Technical Information of China (English)

    Yongkai Zhu; Chuanyao Sun; Weiguo Wu

    2007-01-01

    A new synthetic reagent DPTUHP [diphenyl α-(3-phenylthioureido) hexylphosphonate] containing a hydrocarbon chain nonpolar group,a thioureido,and a phosphonate easter chelating group,has proven to be an effective collector for the flotation of cerussite mineral.The synthetic method utilized the Mannich-type reaction of an N-monosubstituted thiourea,an aldehyde,and triphenyl phosphate in glacial acetic acid solution.The experimental results of flotation of the cerussite mineral show that the collector has stronger collecting ability and higher selectivity in a neutral and a slightly alkaline medium,especially in the pulp of pH=8.Using the measurements by infrared spectroscopy (IR) and X-ray photoelectron spectroscopy (XPS) of the cerussite mineral,the collector,as well as the cerussite treated with the collector,the flotation mechanism of cerussite has been discussed.It is concluded that the adsorption of collector on cerussite is a chemical adsorption through the electron donor atoms of the collector chelating the Pb ( Ⅱ ) of cerussite to form chelate.

  6. CFD simulation and optimization of the capillary throttling of air-flotation unit

    Science.gov (United States)

    Bin, Huang; Yi, Jiajing; Tao, Jiayue; Lu, Rongsheng

    2016-01-01

    With respect to orifice throttling or compensating, capillary throttling has following advantages: smaller mass flow rate and stronger anti-interference ability. This paper firstly gives the required average pressure of air-film when shipping a piece of LCD glass. Then, dimensional flow model of the capillary throttling of air-flotation unit is established. Based on the model, we firstly analyze the flowing process of the lubricated air through the capillary. Secondly, the pressure distribution equation of air-film is derived from the Navier-Stokes Equation. Furthermore, the approximate functional relations between model parameters and static characteristics of the air-film, such as mass flow rate, static bearing capacity, are obtained and then influence of the former on the latter is analyzed . Finally, according to the continuity of air flow, the function relation between model parameters and pressure of core nodes in the air-film is also derived. On foundation of theoretical analysis, the impacts of each model parameter on static characteristics of the air-film flow field, are respectively simulated and analyzed by CFD software Fluent. Based on these simulations and analysis, radius and length of the capillary, density of the gas supply orifices and other model parameters are optimized. Finally, the best unit model is acquired, which greatly improves the static working performance of air-film in air-flotation unit. Research results of this paper can provide guidance and basis for the design and optimization of air-flotation transporting system.

  7. Flotability and flotation separation of polymer materials modulated by wetting agents.

    Science.gov (United States)

    Wang, Hui; Wang, Chong-qing; Fu, Jian-gang; Gu, Guo-hua

    2014-02-01

    The surface free energy, surface tension and contact angles were performed to investigate the properties of wetting agents. Adsorption of wetting agents changes wetting behavior of polymer resins. Flotability of polymer materials modulated by wetting agents was studied, and wetting agents change significantly flotability of polymer materials. The flotability decreases with increasing the concentration of wetting agents, and the wetting ability is lignin sulfonate (LS)>tannic acid (TA)>methylcellulose (MC)>triton X-100 (TX-100) (from strong to weak). There is significant difference in the flotability between polymer resins and plastics due to the presence of additives in the plastics. Flotation separation of two-component and multicomponent plastics was conducted based on the flotability modulated by wetting agents. The two-component mixtures can be efficiently separated using proper wetting agent through simple flotation flowsheet. The multicomponent plastic mixtures can be separated efficiently through multi-stage flotation using TA and LS as wetting agents, and the purity of separated component was above 94%, and the recovery was more than 93%. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Understanding the role of ion interactions in soluble salt flotation with alkylammonium and alkylsulfate collectors.

    Science.gov (United States)

    Ozdemir, Orhan; Du, Hao; Karakashev, Stoyan I; Nguyen, Anh V; Celik, M S; Miller, Jan D

    2011-03-15

    There is anecdotal evidence for the significant effects of salt ions on the flotation separation of minerals using process water of high salt content. Examples include flotation of soluble salt minerals such as potash, trona and borax in brine solutions using alkylammonium and alkylsulfate collectors such as dodecylamine hydrochloride and sodium dodecylsulfate. Although some of the effects are expected, some do not seem to be encompassed by classical theories of colloid science. Several experimental and modeling techniques for determining solution viscosity, surface tension, bubble-particle attachment time, contact angle, and molecular dynamics simulation have been used to provide further information on air-solution and solid-solution interfacial phenomena, especially with respect to the interfacial water structure due to the presence of dissolved ions. In addition atomic force microscopy, and sum frequency generation vibrational spectroscopy have been used to provide further information on surface states. These studies indicate that the ion specificity effect is the most significant factor influencing flotation in brine solutions.

  9. Condutivity effect in electro-coagulation-flotation applied to physico-chemical wastewater treatment

    Directory of Open Access Journals (Sweden)

    Francisco Javier Cuba Terán

    2007-03-01

    Full Text Available This study reports on the effect of conductivity on the simultaneous applicability of water electrolysis , chemical coagulation and flotation fundamentals in the treatment of wastewater with large amounts of suspended matter, characterizing electro-coagulation-flotation (ECF . Results from experiments carried out in a pilot study implanted and operated in the Laboratory of Environment Control (LCA, at the State University of Campinas in Limeira are presented. ECF was developed in an electrolytic reactor where water passed through aluminum electrodes connected to a power supply. Electrochemical reactions promoted Al3+ ions emission from anode, neutralizing repulsive pollutant forces, forming flakes. An evolution of micro hydrogen bubbles occurred, carrying the flakes to the top of the solution, causing flotation and polluter removal. System monitoring aimed at reaching optimal operation conditions regarding time of liquid permanence in the reactor, influence of the NaC1 addition on the increase of affluent conductivity, and influence of polarity inversion over cathodic passivation. Results from carwash wastewater treatment reported 86% efficiency rate for color, 90,15% for turbidity and 85,43% for oil and axle-grease removal.

  10. Determination of iron in drinking water after its flotation concentration by two new dithiocarbamate collectors.

    Science.gov (United States)

    Pavlovska, Gorica; Stafilov, Trajče; Čundeva, Katarina

    2015-01-01

    Two new methods for the determination of iron by atomic absorption spectrometry (AAS) are proposed for drinking water. The determination was made after flotation concentration of Fe by using of two new flotation collectors: lead(II) heptyldithiocarbamate, Pb(HpDTC)2 and cobalt(III) heptyldithiocarbamate Co(HpDTC)3. All important parameters for the two proposed procedures were optimised (pH, mass of Pb, mass of Co, amount of HpDTC(-), type of surfactant, induction time, etc.). Flotation recovery (R) of Fe was very high (from 94.4 to 104.4%) for the two proposed procedures. The detection limit of the methods was 2.17 μg L(-1) for Pb(HpDTC)2 and 2.39 μg L(-1) for Co(HpDTC)3, respectively. The proposed methods have been applied for the analysis of five samples of drinking water. The acquired AAS results for Fe by both new methods were compared with those obtained by inductively coupled plasma-atomic emission spectrometry (AES-ICP). It is shown that they are in good agreement. The results are also confirmed by the method of standard additions.

  11. Flocculation of Pyrite Fines in Aqueous Suspensions with Corn Starch to Eliminate Mechanical Entrainment in Flotation

    Directory of Open Access Journals (Sweden)

    Wei Ge

    2015-10-01

    Full Text Available The hydrophilic flocculation of pyrite fines in aqueous suspensions with corn starch was studied by measuring particle size distribution, microscopy observation and micro-flotation. Furthermore, the interaction of corn starch with pyrite was investigated by determining the adsorption density and based on zeta potential measurements and X-ray photoelectron spectrometer (XPS analysis in this work. The results of the particle size distribution measurement show that corn starch can effectively aggregate pyrite fines, and the pyrite floccules (flocs are sensitive to mechanical stirring. The micro-flotation results suggest that the mechanical entrainment of pyrite fines in flotation can be effectively eliminated through the formation of large-size flocs. The zeta potential of pyrite particles decreases with the addition of corn starch. The XPS results prove that carboxyl groups are generated on the digested corn starch, and both iron hydroxyl compounds and ferrous disulfide on the pyrite surface can chemically interact with the corn starch digested by sodium hydroxide.

  12. Effect of quaternary ammonium salts on flotation behavior of aluminosilicate minerals

    Institute of Scientific and Technical Information of China (English)

    ZHAO Sheng-gui; ZHONG Hong; LIU Guang-yi

    2007-01-01

    The electrokinetic properties and flotation of diaspore, kaolinite, pyrophyllite and illite with quaternary ammonium salts collectors were studied. The results of flotation tests show that the collecting ability of quaternary ammonium salts for the four minerals is in the order(from strong to weak) of octadecyl dimethyl benzyl ammonium chloride(ODBA), cetyl trimethyl ammonium bromide(CTAB), dodecyl trimethyl ammonium chloride(DTAC). Under the condition of alkalescence, it is possible to separate the diaspore from the silicate minerals such as kaolinite, illite and pyrophyllite using quaternary ammonium salts as collector. Isoelectric points (IEP) of diaspore, kaolinite, pyrophyllite and illite are pH=6.0, 3.4, 2.3 and 3.2, respectively. Quaternary ammonium salts can change ζ-potential of the aluminosilicate minerals obviously. The flotation mechanisms were explained by ζ-potential and Fourier transform infrared spectrum (FT-IR) measurements. The results demonstrate that only electrostatic interaction takes place between aluminosilicate minerals (diaspore, kaolinite, pyrophyllite and illite) and quaternary ammonium salts.

  13. The reclamation of mica flakes from tailing disposal using gravity separators and flotation

    Directory of Open Access Journals (Sweden)

    Seied Mohammad Raoof Hoseini

    2016-06-01

    Full Text Available A sample from the small-sized tailing pile of an Iranian mica processing plant was subjected to a series of mica recovery experiments. Mineralogical and microscopic investigations indicated that the dominant mica mineral was phlogopite which was accompanied by plagioclase feldspars. Before beneficiation studies, the particle size distribution of the representative sample was obtained, and the specifications of each size fraction were investigated in detail. It was observed that the largest portion of mica (31% is accumulated in the size range of 0.3 to 2.0 mm. Afterward, gravity concentration and flotation experiments were carried out. Results proved that shaking table could produce a mica concentrate with grade of 74%. Also, according to the flotation tests, it seemed the best size fraction was -150+75, and after that, -100+150. Flotation in combination with attrition scrubbing produced a concentrate with 92% mica content and 70% recovery. Finally, with respect to the results of all implemented experiments, a processing flow sheet was proposed for mica reclamation from the mentioned waste disposal.

  14. Application and comparison of RNN, RBFNN and MNLR approaches on prediction of flotation column performance

    Institute of Scientific and Technical Information of China (English)

    Nakhaei Fardis; Irannajad Mehdi

    2015-01-01

    Evaluation of grade and recovery plays an important role in process control and plant profitability in min-eral processing operations, especially flotation. The accurate measurement or estimation of these two parameters, based on the secondary variables, is a critical issue. Data-driven modeling techniques, which entail comprehensive data analysis and implementation of machine learning methods for system fore-cast, provide an attractive alternative. In this paper, two types of artificial neural networks (ANNs), namely radial basis function neural network (RBFNN) and layer recurrent neural network (RNN), and also a multivariate nonlinear regression (MNLR) model were employed to predict metallurgical performance of the flotation column. The training capacity and the accuracy of these three above mentioned types of models were compared. In order to acquire data for the simulation, a case study was conducted at Sarcheshmeh copper complex pilot plant. Based on the root mean squared error and correlation coeffi-cient values, at training and testing stages, the RNN forecasted the metallurgical performance of the flota-tion column better than RBF and MNLR models. The RNN could predict Cu grade and recovery with correlation coefficients of 0.92 and 0.9, respectively in testing process.

  15. Effect of a cyclonic flotation column on the separation of magnesium from phosphate ore

    Institute of Scientific and Technical Information of China (English)

    Li Guosheng; Liu Jiongtian; Cao Yijun; Wang Dapeng

    2011-01-01

    This study was performed to investigate the effects of the cyclonic separation mechanism on the removal of magnesium from phosphate ore.An analysis of the particle-bubble collision mechanism in a cyclonic force field was used to design two different pulp circulation systems for a cyclonic-static micro-bubble flotation column (FCSMC).Experiments comparing the two conditions were then conducted.Size analysis of the feed and separated products was conducted with a BXF cyclone size analyzer.The results show that about 34.60% of the total MgO content in the feed exists in the -10 μm fraction.This demonstrates that magnesium removal from phosphate ore has the characteristics of a micro-fine particle flotation problem.Under conditions of cyclonic circulation the MgO level of the concentrate is 1.74%,which is lower than that obtained from the column operated in direct-flow circulation by 0.34%.These results indicate that the cyclonic circulation mechanism of the FCSMC can promote removal of micro-fine particles containing magnesium.This is attributed to the function of surface flotation and to the reduction of the lower separation limit under conditions of cyclonic circulation.

  16. Fine coal flotation of plant waste: An in-plant comparison---columns vs. sub-a cell

    Energy Technology Data Exchange (ETDEWEB)

    Ehrlinger, H.P.; Lytle, J.M.; Kohlenberger, L.; Rapp, D.M. (Illinois State Geological Survey, Champaign, IL (USA)); Stephenson, J.; Zipperian, D. (Deister Machine Co., Inc., Fort Wayne, IN (USA)); Sterner, R.; Norris, D. (Kerr-McGee Corp., Oklahoma City, OK (USA))

    1991-01-01

    The objective of this project is to compare the flotation effectiveness of the column flotation and the sub-aeration technology to clean very fine ({minus}100 mesh) coal in the waste streams of coal washing plants. The recent developments in the flotation of fine coal from the waste streams of coal washing plants has been favorable. Good concentrate grades along with a high recovery of energy content have been achieved while rejecting a large percentage of the ash forming minerals and pyrite. However, comparative data of columns vs. sub-aeration cells is not available from a single plant. This project was developed to install a small commercial size Deister Column beside the existing sub-aeration flotation cells at Kerr-McGee's Galatia Plant so that a comparison of the flotation results can be made. A representative split of the fines which normally goes to sub-aeration cells can be diverted without reagent, to the column for continuous side by side flotation testing over an extended period. This quarter additional tests were conducted with reagent variations including xanthate and sodium silicate. The xanthate is a sulfide collector to float the pyritic sulfur with the coal. This information is a guide as to the degree of liberation of pyrite in the coal. The sulfur content in the concentrate increased during these tests indicating the pyrite is partially liberated in the flotation feed. Sodium silicate was added in two tests. While preliminary in the nature, these tests showed lower ash content for the same Btu recovery. 6 tabs.

  17. Numerical Simulations of Two-Phase Flow in a Self-Aerated Flotation Machine and Kinetics Modeling

    KAUST Repository

    Fayed, Hassan E.

    2015-03-30

    A new boundary condition treatment has been devised for two-phase flow numerical simulations in a self-aerated minerals flotation machine and applied to a Wemco 0.8 m3 pilot cell. Airflow rate is not specified a priori but is predicted by the simulations as well as power consumption. Time-dependent simulations of two-phase flow in flotation machines are essential to understanding flow behavior and physics in self-aerated machines such as the Wemco machines. In this paper, simulations have been conducted for three different uniform bubble sizes (db = 0.5, 0.7 and 1.0 mm) to study the effects of bubble size on air holdup and hydrodynamics in Wemco pilot cells. Moreover, a computational fluid dynamics (CFD)-based flotation model has been developed to predict the pulp recovery rate of minerals from a flotation cell for different bubble sizes, different particle sizes and particle size distribution. The model uses a first-order rate equation, where models for probabilities of collision, adhesion and stabilization and collisions frequency estimated by Zaitchik-2010 model are used for the calculation of rate constant. Spatial distributions of dissipation rate and air volume fraction (also called void fraction) determined by the two-phase simulations are the input for the flotation kinetics model. The average pulp recovery rate has been calculated locally for different uniform bubble and particle diameters. The CFD-based flotation kinetics model is also used to predict pulp recovery rate in the presence of particle size distribution. Particle number density pdf and the data generated for single particle size are used to compute the recovery rate for a specific mean particle diameter. Our computational model gives a figure of merit for the recovery rate of a flotation machine, and as such can be used to assess incremental design improvements as well as design of new machines.

  18. The Geometry of Conventionality

    CERN Document Server

    Weatherall, James Owen

    2013-01-01

    Hans Reichenbach famously argued that the geometry of spacetime is conventional in relativity theory, in the sense that one can freely choose the spacetime metric so long as one is willing to postulate a "universal force field". Here we make precise a sense in which the field Reichenbach defines fails to be a "force". We then argue that there is an interesting and perhaps tenable sense in which geometry is conventional in classical spacetimes. We conclude with a no-go result showing that the variety of conventionalism available in classical spacetimes does not extend to relativistic spacetimes.

  19. Conventional Spinal Anaesthesia

    African Journals Online (AJOL)

    patients scheduled for clcctive unilateral lower limb surgery. ... the conventional group were turned supine immediately after injection. Blood pressure, heart rate, respiratory rate and oxygen .... Characteristic Type of spinal anaesthcsia P-value.

  20. Solution chemistry behavior of sodium silicate in flotation of fluorite and scheelite%萤石-白钨矿浮选分离体系中硅酸钠的溶液化学行为

    Institute of Scientific and Technical Information of China (English)

    孙伟; 唐鸿鹄; 陈臣

    2013-01-01

    Complex solution system can be difficult to deal with by conventional solution chemistry calculation. In order to avoid this problem and investigate the influence of sodium silicate on the flotation of scheelite from fluorite, Newton-Raphson method was applied to solution chemistry calculation. And a new kind of species distribution diagram was drawn in terms of changing the total concentration of sodium silicate rather than the activity of silicate or hydrogen ion. According to the study of single-mineral flotation tests, electrokinetic measurements and species distribution diagrams, the selective surface precipitation of calcium silicate on the fluorite was identified to be the major depression mechanism of fluorite in the flotation of separating scheelite from fluorite using sodium silicate as the modifier and sodium oleate as the collector. X-ray photoelectron spectroscopic (XPS) analyses also provided strong evidence for this conclusion. The results show that the selective depression of scheelite flotation from fluorite can be achieved under conditions of moderate depression. The evaluated surface precipitation concentrations are in good agreement with the results of flotation experiments and XPS analysis results. This study also confirms that solution chemistry calculation with Newton-Raphson method has practical value in the interpretation and prediction of mineral flotation.%针对传统溶液化学计算法难以处理复杂溶液体系的问题,采用 Newton-Raphson 数值计算法对复杂溶液体系进行溶液化学计算,利用硅酸钠添加总浓度代替活度绘制新型组分浓度图,研究硅酸钠在萤石白钨矿浮选分离中的作用机理。通过进行纯矿物浮选实验、Zeta电位测试,结合组分浓度图,初步确定硅酸钠在油酸钠浮选分离萤石白钨矿中的主要抑制机理是在萤石表面选择性地生成了硅酸钙沉淀,相关的XPS分析结果进一步证实了这一结论。结

  1. Removal of Gangue Minerals Containing Major Elements from Karlıova-Derinçay (Bingöl) Lignite Using a Reverse Flotation Method

    Science.gov (United States)

    Temel, Halime Abakay

    2015-12-01

    The removal of gangue minerals containing major elements was investigated using a reverse flotation method. Experiments were conducted on lignite samples, with high-ash and low-sulphur contents taken from a lignite field in Karlıova-Derinçay (Bingöl), Turkey. Predominant gangue minerals in the samples were found to be quartz, gypsum, feldspar minerals, mica minerals, and clays (smectite group). Preliminary flotation studies showed that gangue materials are more buoyant than the lignite sample. Some parameters that markedly influence the effectiveness of reverse flotation, such as grinding time, pH, collector type and volume, frother type and volume, and salt, were investigated. Quartz was found to cause a major problem in terms of reverse flotation. Flotation measurements showed that anionic collectors in an acidic medium result in the following element reduction order: sulphur trioxide > ferric oxide > magnesium oxide > calcium oxide > silicon dioxide > aluminium oxide.

  2. Synthesis of N-decyl-1,3-diaminopropanes and its flotation properties on aluminium silicate minerals

    Institute of Scientific and Technical Information of China (English)

    胡岳华; 曹学锋; 李海普; 蒋玉仁; 杜平

    2003-01-01

    N-decyl-1, 3-diaminopropanes (DNs) were synthesized from alkyl-amine acrylonitrile at ambient pressure. With the synthesized DNs as collectors, the flotation of kaolinite, pyrophyllite and illite was conducted and the results were interpreted in terms of the structure-activity relationship. The DNs are found to be more effective collectors than dodecyl amine, exhibiting the highest recovery over a pH range of 4-6. Among the DNs examined, DN12 shows the highest flotation efficiency. The flotation mechanisms were explained in view of the structures of reagents and aluminium silicate minerals. It is demonstrated that DNs can become new selective collectors for reverse floatation to remove aluminium silicate minerals from bauxite.

  3. Effect and mechanism of dolomite with different size fractions on hematite flotation using sodium oleate as collector

    Institute of Scientific and Technical Information of China (English)

    LUO Xi-mei; YIN Wan-zhong; WANG Yun-fan; SUN Chuan-yao; MA Ying-qiang; LIU Jian

    2016-01-01

    The effect of dolomite with different particle size fractions on hematite flotation was studied using sodium oleate as collector at pH of about 9. The effect mechanism of dolomite on hematite flotation was investigated by means of solution chemistry, ultraviolet spectrophotometry (UV), inductively coupled plasma atomic emission spectrometry (ICP-AES) and X-ray photoelectron spectroscopy (XPS). It is observed that dolomite with different size fractions has depressing effect on hematite flotation using sodium oleate as collector, and dolomite could be the "mineral depressant" of hematite using sodium oleate as collector. The reasons for that are concerned with sodium oleate consumption and the adsorption onto hematite of dissolved species of dolomite.

  4. Culture-independent quantification of Salmonella enterica in carcass gauze swabs by flotation prior to real-time PCR

    DEFF Research Database (Denmark)

    Löfström, Charlotta; Schelin, Jenny; Norling, Börje

    2011-01-01

    To facilitate quantitative risk assessment in the meat production chain, there is a need for culture-independent quantification methods. The aim of this study was to evaluate the use of flotation, a non-destructive sample preparation method based on traditional buoyant density centrifugation......, for culture-independent quantification of intact Salmonella in pig carcass gauze swabs (100 cm2) prior to quantitative PCR (qPCR). A novel approach was investigated, excluding the homogenization step prior to flotation, to improve the detection limit and speed up the quantification procedure. The buoyant...... concentrations of ≥ 6.1 × 108 CFU/swab sample, but not by concentrations ≤ 6.1 × 106 CFU/swab sample. By using the gauze swabs directly in the flotation procedure, the homogenization step normally used for preparation of food-related samples could be excluded, which simplified the culture independent...

  5. Culture-independent qunatification of Salmonella enterica in carcass gauze swabs by flotation prior to real-time PCR

    DEFF Research Database (Denmark)

    Löfström, Charlotta; Schelin, Jenny; Norling, Börje

    2010-01-01

    To facilitate quantitative risk assessment in the meat production chain, there is a need for culture-independent quantification methods. The aim of this study was to evaluate the use of flotation, a non-destructive sample preparation method based on traditional buoyant density centrifugation......, for culture-independent quantification of intact Salmonella in pig carcass gauze swabs (100 cm2) prior to quantitative PCR (qPCR). A novel approach was investigated, excluding the homogenization step prior to flotation, to improve the detection limit and speed up the quantification procedure. The buoyant...... concentrations of ≥ 6.1×108 CFU/swab sample, but not by concentrations ≤ 6.1×106 CFU/swab sample. By using the gauze swabs directly in the flotation procedure, the homogenization step normally used for preparation of food-related samples could be excluded, which simplified the culture independent quantification...

  6. ETAAS determination of thallium and silver from water matrix after colloidal precipitate flotation using lead(II hexamethylenedithiocarbamate

    Directory of Open Access Journals (Sweden)

    TRAJCE STAFILOV

    2001-10-01

    Full Text Available Afast method for the preconcentration of thallium and silver in nanogram quantities in fresh drinking waters (source, well, tap and waters for irrigation using colloidal precipitate flotation is described. Lead(II hexamethylenedithiocarbamate, Pb(HMDTC2 played the role of flotation collector. The experimental conditions for the successful separation of thallium and silver (mass of Pb, amount ofHMDTC-, pHof the system, induction time, type of surfactant etc. were optimized. After flotation separation from the mother liquor, the solid sublate containing traces of thallium and silver was dissolved and the analytes were determined by electrothermal atomic absorption spectrometry (ETAAS. The results of the ETAAS analysis are compared with those obtained by inductively coupled plasma-atomic emission spectrometry. The detection limit for thallium by this method is 0.027 mg/l, and for silver 0.005 microg/l.

  7. Culture-independent quantification of Salmonella enterica in carcass gauze swabs by flotation prior to real-time PCR

    DEFF Research Database (Denmark)

    Löfström, Charlotta; Schelin, Jenny; Norling, Börje

    2011-01-01

    To facilitate quantitative risk assessment in the meat production chain, there is a need for culture-independent quantification methods. The aim of this study was to evaluate the use of flotation, a non-destructive sample preparation method based on traditional buoyant density centrifugation......, for culture-independent quantification of intact Salmonella in pig carcass gauze swabs (100 cm2) prior to quantitative PCR (qPCR). A novel approach was investigated, excluding the homogenization step prior to flotation, to improve the detection limit and speed up the quantification procedure. The buoyant...... concentrations of ≥ 6.1 × 108 CFU/swab sample, but not by concentrations ≤ 6.1 × 106 CFU/swab sample. By using the gauze swabs directly in the flotation procedure, the homogenization step normally used for preparation of food-related samples could be excluded, which simplified the culture independent...

  8. Study on performance optimization of coal flotation machine%煤炭浮选机性能优化研究

    Institute of Scientific and Technical Information of China (English)

    訾涛; 韩恒旺

    2016-01-01

    Aiming at the shortage of low capability,large power consumption,high failure rate of stirring motor,and difficult maintenance of XJX⁃T12 flotation machine in Liangbei Coal Mine,presence processing,issues such as electrical,the plant focuses on the XJX⁃T12⁃type flotation machine feed form,stirring mechanism and installation stirring motor and other key areas,combined with the characteris⁃tics XJM⁃S12 flotation machine,the existing XJX⁃T12 flotation machine has been transformed. After transformation to improve the han⁃dling capacity of the flotation machine,reducing the power consumption and the stirring motor repair strength,so that greatly enhance the performance of the flotation machine,and achieved good economic and social benefits.%针对梁北选煤厂XJX⁃T12型浮选机存在的处理能力不足、电能消耗大、搅拌电机故障率高、电机维修困难等问题,重点分析了XJX⁃T12型浮选机的入料形式、搅拌机构以及搅拌电机的安装方式等关键环节,并结合XJM⁃S12浮选机的特点,对现有的XJX⁃T12浮选机进行了改造。改造后提高了浮选机的处理量、降低了电能消耗及搅拌电机的维修强度,使浮选机的性能大幅度提升,取得了良好的经济和社会效益。

  9. Evaluation of rhamnolipid (RL) as a biosurfactant for the removal of chromium from aqueous solutions by precipitate flotation.

    Science.gov (United States)

    Salmani Abyaneh, Ali; Fazaelipoor, Mohammad Hassan

    2016-01-01

    Rhamnolipid (RL) is a biosurfactant which is produced by the bacterial species Pseudomonas aeruginosa. Although applications of this material have been examined in various fields, its applications in the flotation of heavy metals remain to be explored. In this research, rhamnolipid was applied as a collector in the flotation of Cr(III) from aqueous solutions. FeSO4 was used for the precipitation of Cr(VI) to Cr(III) which was subsequently removed by flotation. A two level full factorial design (with center points) was used to evaluate the effects of pH, air flow rate, RL/Cr and Fe/Cr molar ratios on the performance of the flotation system. The results showed that the biosurfactant was highly effective in the removal of chromium, and all of the factors had significant effects on the flotation performance. The chromium removal efficiencies of greater than 95% were obtained with the initial chromium concentration of 40 ppm within 5 min. Kinetic studies showed that a first order kinetic model was appropriate to describe the precipitate flotation of Cr(III) using rhamnolipid as a collector. The interference of NaCl, CaCl2, CaSO4, and CaCO3 on the Cr removal was also investigated, and it was demonstrated that CaSO4 and CaCO3 as sparingly water soluble salts, and CaCl2 as a contributor to water hardness had significant negative impacts on Cr removal efficiency of rhamnolipid.

  10. Sensitivity and efficiency of selected coproscopical methods-sedimentation, combined zinc sulfate sedimentation-flotation, and McMaster method.

    Science.gov (United States)

    Becker, Ann-Christin; Kraemer, Amelie; Epe, Christian; Strube, Christina

    2016-07-01

    Coproscopical methods used in veterinary-parasitological diagnostics were validated according to their sensitivity (Se) and egg recovery rate [efficiency (Ef)]. Validation of the combined sedimentation-flotation method and the modified McMaster method was performed by using feces spiked with eggs of Ancylostoma caninum, Uncinaria stenocephala, Cooperia oncophora, cyathostomins, Ascaris suum, Toxascaris leonina, Toxocara canis, Trichuris vulpis, Moniezia expansa, and Anoplocephala perfoliata. For validation of the sedimentation method, Fasciola hepatica eggs were used. With the combined sedimentation-flotation method using ZnSO4 as flotation medium [specific gravity (SG) 1.30], 5 g fecal samples of all tested parasite species (concentration levels 1, 5, 10, 20, 40, 60, and 80 epg) were reproducibly detected "positive" (100 % Se) as of 80 epg. The Ef of the combined sedimentation-flotation method, defined as percentage of rediscovered eggs, revealed clear differences between parasites and showed the highest value for cyathostomins and the lowest for U. stenocephala and T. leonina eggs. The average Ef for all parasite species at 80 epg was 1.50 %. With the McMaster method (concentration levels 1, 30, 50, 80, 100, 500, and 1000 epg), all tested parasite species were detected reliably positive as of 500 epg with a mean Ef of 46.4 %. When evaluating the sedimentation method (concentration levels 1, 5, 10, 15, 20, 25, and 30 epg), F. hepatica eggs were reproducibly found in 5 g fecal samples as of 20 epg with 20.0 % Ef. The result that the combined zinc sulfate sedimentation-flotation method (SG 1.30) as flotation medium provides diagnostic certainty only as of 80 epg has to be considered at preventing zoonoses. If pet owners wish to prevent any zoonotic infection ("zero tolerance"), a monthly anthelminthic treatment should be advised instead of monthly fecal examinations.

  11. Utilization of flotation wastes of copper slag as raw material in cement production.

    Science.gov (United States)

    Alp, I; Deveci, H; Süngün, H

    2008-11-30

    Copper slag wastes, even if treated via processes such as flotation for metal recovery, still contain heavy metals with hazardous properties posing environmental risks for disposal. This study reports the potential use of flotation waste of a copper slag (FWCS) as iron source in the production of Portland cement clinker. The FWCS appears a suitable raw material as iron source containing >59% Fe(2)O(3) mainly in the form of fayalite (Fe(2)SiO(4)) and magnetite (Fe(3)O(4)). The clinker products obtained using the FWCS from the industrial scale trial operations over a 4-month period were characterised for the conformity of its chemical composition and the physico-mechanical performance of the resultant cement products was evaluated. The data collected for the clinker products produced using an iron ore, which is currently used as the cement raw material were also included for comparison. The results have shown that the chemical compositions of all the clinker products including those of FWCS are typical of a Portland cement clinker. The mechanical performance of the standard mortars prepared from the FWCS clinkers were found to be similar to those from the iron ore clinkers with the desired specifications for the industrial cements e.g. CEM I type cements. Furthermore, the leachability tests (TCLP and SPLP) have revealed that the mortar samples obtained from the FWCS clinkers present no environmental problems while the FWCS could act as the potential source of heavy metal contamination. These findings suggest that flotation wastes of copper slag (FWCS) can be readily utilised as cement raw material due to its availability in large quantities at low cost with the further significant benefits for waste management/environmental practices of the FWCS and the reduced production and processing costs for cement raw materials.

  12. Particle-bubble aggregate stability on static bubble generated by single nozzle on flotation process

    Science.gov (United States)

    Warjito, Harinaldi, Setyantono, Manus; Siregar, Sahala D.

    2016-06-01

    There are three sub-processes on flotation. These processes are intervening liquid film into critical thickness, rupture of liquid film forming three phase contact line, and expansion three phase contact line forming aggregate stability. Aggregate stability factor contribute to determine flotation efficiency. Aggregate stability has some important factors such as reagent and particle geometry. This research focussed on to understand effect of particle geometry to aggregate stability. Experimental setup consists of 9 x 9 x26 cm flotation column made of glass, bubble generator, particle feeding system, and high speed video camera. Bubble generator made from single nozzle with 0.3 mm diameter attached to programmable syringe pump. Particle feeding system made of pipette. Particle used in this research is taken from open pit Grasberg in Timika, Papua. Particle has sub-angular geometry and its size varies from 38 to 300 µm. Bubble-particle interaction are recorded using high speed video camera. Recordings from high speed video camera analyzed using image processing software. Experiment result shows that aggregate particle-bubble and induction time depends on particle size. Small particle (38-106 µm) has long induction time and able to rupture liquid film and also forming three phase contact line. Big particle (150-300 µm) has short induction time, so it unable to attach with bubble easily. This phenomenon is caused by apparent gravity work on particle-bubble interaction. Apparent gravity worked during particle sliding on bubble surface experience increase and reached its maximum magnitude at bubble equator. After particle passed bubble equator, apparent gravity force experience decrease. In conclusion particle size from 38-300 µm can form stable aggregate if particle attached with bubble in certain condition.

  13. Particulate COD balance of particulate cod in eletrocuagulation/flotation reactor treating tannery effluent

    Directory of Open Access Journals (Sweden)

    Rodrigo Babora Borri

    2012-04-01

    Full Text Available Mass balance or particulate organic matter was studied in terms of COD, by means of electrocoagulation/flotation (ECF reactor treating tannery effluent. Reactor was operated in fill and draw (batch mode. Operating in hydraulic residence time of 65 minutes, ECF reactor reached 55 % COD removal. Although volatile solids were also removed from liquid phase (removal of 40%, fixed solids concentration, and hence total solids concentration, showed to be higher in withdrawn effluent than in ECF’s influent. This was assigned to NaCl added in order to enhance conductivity in wastewater.

  14. COMPUTATIONAL FLUID DYNAMICS APPLIED TO THE STUDY OF INCLUSIONS FLOTATION IN STEELS FOR AUTOMOTIVE INDUSTRY

    Directory of Open Access Journals (Sweden)

    Ângelo Máximo Fernandes Marins

    2013-03-01

    Full Text Available The practice of inert gas bubbling in steel refining ladle aims the removal of non-metallic inclusions, in addition to thermal and compositional homogenization. Through physical and mathematical models of a secondary ladle refining, the effects of bubbling flow of inert gas and the number of porous plugs located at the bottom of the ladle are investigated. The velocity fields and flotation of non-metallic inclusions are analyzed by physical and mathematical modeling. The results are validated by analysis of images (PIV and the macroscopic model is compared by industrial results for inclusions analysis for steels used in the automotive sector

  15. Acid leaching of oxide-sulphide copper ore prior the flotation: A way for an increased metal recovery

    Directory of Open Access Journals (Sweden)

    Sokić Miroslav D.

    2015-01-01

    Full Text Available Copper mine "Cerovo"- East Serbia as well as the other ore bodies in its vicinity contain a significant amount of oxide copper minerals in their uper layers (>40%. Processing of such mixed ores by the existing concentration technologies leads to a substantial copper losses (<60%. Reduction of "oxide copper", by acid leaching prior the flotation concentration, can increase the overall copper efficiency up to more than 70% in the single-stage leaching, achieving an efficiency in the flotation concentration stage higher than 75%. Based on the performed experimental results the flow sheet for processing of the mixed oxide-sulphide copper ore is proposed.

  16. Development of a technology for obtaining flotation reagent oxane-3 for carbon mineral raw materials of Kazakhstan

    Directory of Open Access Journals (Sweden)

    Sergey Kalugin

    2014-12-01

    Full Text Available The paper represents the results of development of a technology for obtaining oxane-3 and its application for enrichment of carbon mineral raw materials. Studies on enrichment of a shungite rock showed that the increase of a pulp temperature to 30°C significantly improves the characteristics and rate of the flotation process. Measured indicators of a shungite rock enrichment using Flotol B were lower in comparison with an enrichment by oxane-3. For schungite mineral, it was established that the obtained heterocyclic compound can replace existing industrial flotation reagents in enrichment processes.

  17. Recovering lithium mica from the waste after mining Sn-W ores through the use of flotation

    OpenAIRE

    Samková, Radmila

    2009-01-01

    Flotation is one of the possibilities of recovering useful components both at preparation and processing of raw materials, and at recycling and exploitation of a variety of wastes. In the area of Krušné hory occur a number of dumping sites where wastes from treatment of Sn-W ores are deposited, characterized by enhanced content of lithium, rubidium and cesium. These elements are bound to lithium mica – zinwaldite; its recovering is possible through the use of flotation. This paper is devoted ...

  18. Study on application of flotation column to reverse flotation of ultrafine hematite%浮选柱在微细粒赤铁矿反浮选中的应用研究

    Institute of Scientific and Technical Information of China (English)

    王伟之; 韩苗苗; 刘天一

    2013-01-01

    为了降低浮选尾矿品位,对冀东地区某赤铁矿选厂的磁选精矿进行了旋流-静态微泡浮选柱的反浮选试验研究.试验中分别进行了浮选柱操作参数、药剂制度条件试验及浮选流程试验.结果表明,采用浮选柱经一粗一精一扫流程可获得精矿品位68.22%、回收率79.51%的良好指标,扫选尾矿品位降至8.55%.%In order to reduce the grade of flotation tailings,the reverse flotation tests of the magnetic concentrate in a hematite processing plant of Jidong area were conducted by using the cyclone-static microbubble floatation column.The conditional tests of flotation column operating parameters and the reagent system as well as the test for flotation process flow were carried out.The results indicated that by using the cyclone-static microbubble floatation column,iron concentrate with TFe grade of 68.22%,yield of 79.51% and tailings with grade of 8.55% were obtained by one roughing,one cleaning and one scavenging.

  19. Survey of dissolved air flotation system efficiency for reduce of pollution of vegetable oil industry wastewater.

    Science.gov (United States)

    Keramati, H; Alidadi, H; Parvaresh, A R; Movahedian, H; Mahvi, A H

    2008-10-01

    The aim of this research was to sudy the reduction of pollution of vegetable oil manufacturing wastewater with DAF system. At first phase of this examination, the optimum dosage of the coagulants was determined. The coagulants that used in this study were Alum and Ferric Chloride. The second phase was flotation in this series of examinations, oil, COD, total solid, volatile solid, fixed solid and suspended solid measured in raw wastewater and the effluent of the DAF pilot. Optimum value of pH for alum and ferric chloride obtained 7.5 and 5.5, respectively. Optimum dosage for these obtained 30 and 32 mg L(-1) in this research. Mean removal for the parameters ofoil, COD, total solid, volatile solid, fixed solid and suspended solid obtained 75.85, 78.27, 77.32, 82.47, 73.52 and 85.53%, respectively. With pressure rising from 3 to 4 and 5 atm removing rate of COD, total solid, volatile solid, fixed solid parameters reduced, but oil and suspended solid have increase. In addition, following increase of flotation time up to 120 sec all of the measured parameters have increase in removing rate. Optimum A/S for removal of COD, total solid, volatile solid, fixed solid parameters obtained 0.001 and for oil and suspended solid obtained 0.0015.

  20. Design and Research of Similarity and its Serialization of the Flotation Machine’s Key Structure

    Institute of Scientific and Technical Information of China (English)

    DONG Yu-de; DING Zhan-you; YANG Shan-lai; BAI Su-cheng; PAN Kai

    2014-01-01

    Aiming at the problems such as more repeatedly design and longer design cycle, in this paper, the similarity theory was introduced to the design process of the key structures of flotation machine. The impeller and U-shaped tank of flotation machine system were analyzed as similarity unit. Meanwhile, the level of similarity of the units and the similarity of the system were calculated. Based on the analysis of the impeller and the size of U-shaped tank, the similarity criteria were derived. The derived conclusions are: (1) The relationship between the diameter of the impeller and the volume of the tank was power function and calculated as the similarity criteria of the impeller (2) The relationship between the ratio between the U-shaped tank’s cross-sectional area and impeller’s diameter and the volume of the tank was power function and calculated as the similarity criterions of the U-shaped tank. Using the similarity criterion combined with computer technology and database technology to realize part and system serialization design. The results show that the research can avoid repeatedly design, shorten design cycle, and raise the design efficiency.

  1. Floc flotation of jamesonite fines in aqueous suspensions induced by ammonium dibutyl dithiophosphate

    Institute of Scientific and Technical Information of China (English)

    张婷; 覃文庆

    2015-01-01

    The hydrophobic flocculation of jamesonite fines in aqueous suspensions induced by ammonium dibutyl dithiophosphate was investigated using laser particle size analysis, microscope analysis, electrophoretic light scattering and infrared spectroscopy. Single minerals of 4.607 µm for the 50% volumetric diameters were researched by varying several parameters, including pH, ammonium dibutyl dithiophosphate concentration, stirring strength and kerosene addition. It is found that the maximal floatability of jamesonite fines is induced by ammonium dibutyl dithiophosphate at pH 6, and the floc flotation increases with increasing ammonium dibutyl dithiophosphate concentration despite a simultaneous increase in the negativeζpotential of jamesonite, meaning that hydrophobic interaction between the particles increases much more strongly than electric double layer repulsion from the adsorption of ammonium dibutyl dithiophosphate. It is also found that the floc flotation is closely correlated with the size of flocs, which is strongly influenced by the stirring strength and enhanced by the addition of a small amount of kerosene. The results of FTIR spectra indicate that adsorption of ammonium dibutyl dithiophosphate onto jamesonite is chemical adsorption and the adsorption product is lead dibutyl dithiophosphate.

  2. Effects of Metallic Ions on the Flotation of Spodumene and Beryl

    Institute of Scientific and Technical Information of China (English)

    WANG Yu-hua; YU Fu-shun

    2007-01-01

    Effects of multivalent metallic cations, such as Ca2+ and Fe3+, on the flotation of spodumene and beryl were studied. The results show that Fe3+ and Ca2+ exhibit efficient activation on the flotation of spodumene and beryl. The activation of Fe3+ happens quite well within a pH range of 6-9 while the concentration of Fe3+ is 35 mg/L. Efficient activation of Ca2+ takes place over at a pH over 11.6 at a concentration of 140 mg/L. The zeta potential of beryl and spodumene shifts slightly to positive values when activated by Ca2+, but markedly by Fe3+. New stretching frequencies of 1594.24 cm-1 and 1587.13 cm-1 have been found in the FTIR spectra of the two minerals after their interaction with Fe3+ and the collector. These new stretching frequencies are the asymmetric stretching frequencies of COO- (carboxyl anion), so thecollector may be chemically absorbed on the surface of Fe3+-activated beryl and spodumene.

  3. Application of dissolved air flotation process for industrial sludge thickening: A laboratory-scale study

    Directory of Open Access Journals (Sweden)

    Ali Atamaleki

    2017-01-01

    Full Text Available Aims: Increasing population density in cities has led to an increase in industrial and municipal wastewater sludge generation volume. Dissolved air flotation (DAF can widely be used for water and wastewater treatment. The aim of our study is to evaluate some DAF design parameters on biological sludge thickening which generated from an industrial wastewater treatment plant. Materials and Methods: This experimental research had been carried out as a laboratory-scale study on DAF process to thickening of the biological sludge. The required amount of sludge was taken once from the Amikabir industrial town wastewater treatment plant in Kashan, Iran. After determination of optimal recycling rate, pH, and coagulant dose, effects of pressure (3, 5, and 7 atm, flotation time (5 and 10 min, and coagulant addition were evaluated on DAF process efficiency. Results: According to this investigation results, the optimal pH and dose of coagulant were obtained 7.5 and 200 mg/L, respectively. Maximum process efficiency for the reduction of total dissolved solids (TDSs, total solids (TSs, and turbidity parameters was 61.01%, 84.02%, and 97%, respectively. Furthermore, the results showed that in contrast to time, coagulant addition and pressure have significant effect on DAF process. Conclusion: DAF process had suitable thickening efficiency to removal of TDS, TS, and turbidity on biological activated sludge.

  4. Additive-free harvesting of oleaginous phagotrophic microalga by oil and air flotation.

    Science.gov (United States)

    Hosseini, Majid; Starvaggi, Haley A; Ju, Lu-Kwang

    2016-07-01

    A unique oleaginous phagotrophic microalga Ochromonas danica is poised for effective lipid production from waste. Cell harvesting and dewatering are major costs in making algae-based products. In this work an effective additive-free harvesting method was developed, taking advantage of O. danica's comparatively more hydrophobic surface and larger size. The algal cells' partitioning to oil/water interface was evaluated. Recovery by flotation with waste cooking oil was optimized using an L-9 Taguchi orthogonal-array design. Further, additive-free cell collection and concentrating by air flotation was studied for the effects of both physical factors (column dimension, air-stone pore size, sample-to-column volume ratio) and culture properties (pH, culture growth stage, cell concentration, and pure versus impure cultures). The optimized process consistently achieved >90 % recovery in a single stage. 98+ % recovery could be achieved when starting concentrations were >10(8) cells/ml, or potentially using a two- or multi-stage process for diluter cultures.

  5. 锂辉石浮选尾矿中长石和石英浮选分离%Flotation Separation Process of Feldspar and Quartz of a Spodumene Flotation Tailings

    Institute of Scientific and Technical Information of China (English)

    张杰; 王维清; 董发勤; 黄阳; 傅开彬; 冯启明

    2013-01-01

      对某地锂辉石浮选尾矿进行长石和石英浮选分离试验,探索了无氟有酸法和有氟有酸法2种浮选工艺。氢氟酸法进行了搅拌擦洗时间、氢氟酸用量、十二胺用量和浮选时间等条件试验,在条件试验的基础上,依次进行了长石浮选开路试验和闭路试验。结果表明,通过“1粗2扫1精”闭路流程试验,可获得K2O、Na2O品位分别为4.13%、7.46%,回收率分别为98.03%、98.42%的长石精矿。对产品进行质量检查,长石精矿、石英精矿(长石浮选尾矿)均达到工业要求,实现了锂辉石浮选尾矿综合利用的目的。%Research on the flotation separation of feldspar and quartz of a spodumene flotation tailings, explored the two flotation process of non-fluoride with acid and hydrofluoric acid. The hydrofluoric acid carried out the stirring time, hydrofluoric acid amount, dodecylamine amount and flotation time condition test, on the basis of condition test, the open-flow test and closed circuit test of feldspar flotation were determined. The results show that through the closed circuit test of"one roughing, two scavenging and one cleanings", the feldspar concentrate with the grade of 4.13%and recovery of 98.03%of K2O and the grade of 7.46%and recovery of 98.42%of Na2O was obtained. Production quality inspection show that the feldspar concentrate and quartz concentrate (feldspar flotation tailings) achieved industrial requirements, realised the purpose of comprehensive utilization of spodumene flotation tailings.

  6. Study on the influence of the structural parameters of the flotation column on the rate of strontium%浮选柱结构参数对锶的浮选率影响的研究

    Institute of Scientific and Technical Information of China (English)

    周昳; 郭丽; 吕述姣; 商少明

    2011-01-01

    The flotation of strontium was studied by flotation column flotation. Under the optimal flotation condition of strontium, the influence of the height and diameter of the flotation column, air chamber, the model of microporous foaming generator and the shape of the flotation column was researched. Through experiments, it was found that the diameter of flotation column, the model of mircoporous foaming generator, air chamber and the spherical flotation column all had great impact on flotation; the effect of the height of flotation column was trivial, on the other hand, the proper height of flotation column can shorten flotation time; when the appropriate size and spherical flotation column are chosen, the highest rate of strontium flotation can be up to 97%.%研究了浮选柱浮选法对锶的浮选.考察了在锶最优浮选条件下浮选柱的高度、直径、布气室、微孔发泡器型号及柱形变化对浮选柱浮选法的影响.通过实验可知,浮选柱直径、发泡器、布气室、球型浮选柱都对锶的浮选率都有很大的影响;而浮选柱高度对浮选率的影响不大,但是在相同条件下,合适浮选柱高度可以缩短浮选时间;当选择合适的尺寸和球形柱,锶的浮选率最高可以达到97%.

  7. Conventional cerebrospinal fluid scanning

    Energy Technology Data Exchange (ETDEWEB)

    Schicha, H.

    1985-06-01

    Conventional cerebrospinal fluid scanning (CSF scanning) today is mainly carried out in addition to computerized tomography to obtain information about liquor flow kinetics. Especially in patients with communicating obstructive hydrocephalus, CSF scanning is clinically useful for the decision for shunt surgery. In patients with intracranial cysts, CSF scanning can provide information about liquor circulation. Further indications for CSF scanning include the assessment of shunt patency especially in children, as well as the detection and localization of cerebrospinal fluid leaks.

  8. Use of life jackets and other types of flotation for in-water recreation in designated swim areas in Washington State.

    Science.gov (United States)

    Quan, Linda; Mangione, Thomas; Bennett, Elizabeth; Chow, Wendy

    2017-04-19

    Most fatal drownings worldwide occur in open water. Flotation devices may protect swimmers. Their use by those recreating in water has not been described. Observational survey of swimmers and waders at designated swim sites at lakes and rivers evaluated them by age group, sex, type of flotation used (life jacket vs substandard flotation, eg, water wings, noodles, inflatables) and, for children life jackets, decreased with increasing age. Children life jackets (50.5%). Children life jackets than teens (RR 6.78, 3.62 to 12.71); boys were more likely than girls to wear life jackets (RR 1.47, 1.18 to 1.83). While teenagers and adults used flotation (29.5% and 23.5%), they rarely used life jackets (2-3%). Boys life jackets than girls. Substandard flotation use did not differ among age groups (15.5-26.5%) but their use was greater among females in most age groups. Flotation devices were frequently used for recreational wading and swimming in open water by all age groups. Life jacket use was limited to children. Promoting use of flotation devices with safety standards that provide protection as well as fun could potentially decrease open water drowning rates. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  9. A comparison study of column flotation technologies for cleaning Illinois coal. Technical report, September 1--November 30, 1993

    Energy Technology Data Exchange (ETDEWEB)

    Honaker, R.Q.; Paul, B.C. [Southern Illinois Univ., Carbondale, IL (United States). Dept. of Mining Engineering

    1993-12-31

    The objectives of this research project are to optimize the performance of six commercially available column technologies for the treatment of Illinois Basin coal fines and to compare their performance on the basis of the recovery-grade curve and column throughput capacity. A statistically-designed experimental program will be conducted to optimize the critical operating performance values of each flotation column. The operating values suggested by the vendor will be used as the center point of the design. The ultimate recovery-grade curve and-the maximum throughput capacity for each column will be determined by conducting further tests using the optimum operating parameter values. During this reporting period, the flotation columns that were not already present were purchased and received. Installation of all the flotation columns was completed with the exception of the Packed-Column which is presently being mounted. A total of 25 fifty-five gallon drums of Illinois No. 5 flotation feed coal ({minus}100 mesh) was collected at a local preparation plant to be used as the feed for the comparison tests. A complete characterization of this coal sample will be conducted during the next reporting period.

  10. Culture-independent qunatification of Salmonella enterica in carcass gauze swabs by flotation prior to real-time PCR

    DEFF Research Database (Denmark)

    Löfström, Charlotta; Schelin, Jenny; Norling, Börje

    2010-01-01

    To facilitate quantitative risk assessment in the meat production chain, there is a need for culture-independent quantification methods. The aim of this study was to evaluate the use of flotation, a non-destructive sample preparation method based on traditional buoyant density centrifugation, for...

  11. Treating Stress-Related Pain with the Flotation Restricted Environmental Stimulation Technique: Are There Differences between Women and Men?

    Directory of Open Access Journals (Sweden)

    Sven Å Bood

    2009-01-01

    Full Text Available The aim of the present study was to explore, for the first time, sex differences among patients diagnosed with stress-related pain before and after flotation restricted environmental stimulation technique (REST treatment, delivered 12 times during seven weeks. The present study included 88 patients (69 women, 19 men from three different studies (post hoc analysis. They had been diagnosed by a physician as having chronic stress-related muscle tension pain. The analyses indicated that the flotation-REST treatment had beneficial effects on stress, anxiety, depression, sleep quality and pain and that there were few sex differences. Women were more depressed than men before treatment, but after treatment there was no difference between sexes. However, there was a sex difference in the ability to endure experimentally induced pain, suggesting that men exhibited greater endurance both before and after the flotation-REST treatment. The results also showed, for the first time, that both sexes improved their ability to endure experimentally induced pain (higher scores for upper pain threshold following the successful flotation-REST pain treatment.

  12. Fine coal flotation of plant waste: An in-plant comparison - columns vs. sub-A cell

    Energy Technology Data Exchange (ETDEWEB)

    Ehrlinger, H.P. III; Lytle, J.M.; Kohlenberger, L.; Rapp, D.M. (Illinois State Geological Survey, Champaign, IL (United States)); Stephenson, J.; Zipperian, D. (Deister Machine Co., Inc., Fort Wayne, IN (United States)); Sterner, R.M.; Norris, D. (Kerr-McGee Corp., Oklahoma City, OK (United States))

    1991-01-01

    The objective of this project is to compare the flotation effectiveness of the column flotation and the sub-aeration technology to clean very fine ({minus}100 mesh) coal in the waste streams of coal washing plants. Good concentrate grades along with a high recovery of energy content have been achieved while rejecting a large percentage of the ash forming minerals and pyrite. However, comparative data of columns vs. sub-aeration cells is not available from a single plant. This project was developed to install a small commercial size Deister Column beside the existing sub-aeration flotation cells at Kerr-McGee's Galatia Plant so that a comparison of the flotation results can be made. A representative split of the fines which normally goes to sub-aeration cells can be diverted without reagent, to the column for continuous side by side flotation testing over an extended period. The Deister Column was installed during the quarter along with the sampling system and tailings volume measuring apparatus. Parts of several weeks were spent in assuring that realistic goals could be obtained. During the de-bugging period it was found that water pressure and air pressure within the plant was not constant due to cleanup hoses which were on the same fresh water line to assure constant water and air pressure to the column during testing periods. Most of the shakedown testing was completed in April and May. Preliminary tests have been run in which high grade concentrates have been made but with low Btu recoveries. Additional tests with increased reagent rates are planned to increase Btu recoveries and will be reported at the Contractors Conference and in the final report. 24 figs., 1 tab.

  13. Conventional and unconventional superconductivity

    Science.gov (United States)

    Fernandes, R. M.

    2012-02-01

    Superconductivity has been one of the most fruitful areas of research in condensed matter physics, bringing together researchers with distinct interests in a collaborative effort to understand from its microscopic basis to its potential for unprecedented technological applications. The concepts, techniques, and methods developed along its centennial history have gone beyond the realm of condensed matter physics and influenced the development of other fascinating areas, such as particle physics and atomic physics. These notes, based on a set of lectures given at the 2011 Advanced Summer School of Cinvestav, aim to motivate the young undergraduate student in getting involved in the exciting world of conventional and unconventional superconductors.

  14. Strategic interaction and conventions

    Directory of Open Access Journals (Sweden)

    Espinosa, María Paz

    2012-03-01

    Full Text Available The scope of the paper is to review the literature that employs coordination games to study social norms and conventions from the viewpoint of game theory and cognitive psychology. We claim that those two alternative approaches are in fact complementary, as they provide different insights to explain how people converge to a unique system of self-fulfilling expectations in presence of multiple, equally viable, conventions. While game theory explains the emergence of conventions relying on efficiency and risk considerations, the psychological view is more concerned with frame and labeling effects. The interaction between these alternative (and, sometimes, competing effects leads to the result that coordination failures may well occur and, even when coordination takes place, there is no guarantee that the convention eventually established will be the most efficient.

    El objetivo de este artículo es presentar la literatura que emplea los juegos de coordinación para el estudio de normas y convenciones sociales, que se han analizado tanto desde el punto de vista de la teoría de juegos como de la psicología cognitiva. Argumentamos en este trabajo que estos dos enfoques alternativos son en realidad complementarios, dado que ambos contribuyen al entendimiento de los procesos mediante los cuales las personas llegan a coordinarse en un único sistema de expectativas autorrealizadas, en presencia de múltiples convenciones todas ellas igualmente viables. Mientras que la teoría de juegos explica la aparición de convenciones basándose en argumentos de eficiencia y comportamientos frente al riesgo, el enfoque de la psicología cognitiva utiliza en mayor medida consideraciones referidas al entorno y naturaleza de las decisiones. La interacción entre estos efectos diferentes (y en ocasiones, rivales desemboca con frecuencia en fallos de coordinación y, aun cuando la coordinación se produce, no hay garantía de que la convención en vigor sea la m

  15. Biodiesel from conventional feedstocks.

    Science.gov (United States)

    Du, Wei; Liu, De-Hua

    2012-01-01

    At present, traditional fossil fuels are used predominantly in China, presenting the country with challenges that include sustainable energy supply, energy efficiency improvement, and reduction of greenhouse gas emissions. In 2007, China issued The Strategic Plan of the Mid-and-Long Term Development of Renewable Energy, which aims to increase the share of clean energy in the country's energy consumption to 15% by 2020 from only 7.5% in 2005. Biodiesel, an important renewable fuel with significant advantages over fossil diesel, has attracted great attention in the USA and European countries. However, biodiesel is still in its infancy in China, although its future is promising. This chapter reviews biodiesel production from conventional feedstocks in the country, including feedstock supply and state of the art technologies for the transesterification reaction through which biodiesel is made, particularly the enzymatic catalytic process developed by Chinese scientists. Finally, the constraints and perspectives for China's biodiesel development are highlighted.

  16. STATUS AND RESEARCH PROGRESS OF ZINC OXIDE ORE FLOTATION%氧化锌矿的浮选现状与研究进展

    Institute of Scientific and Technical Information of China (English)

    宋龑; 刘全军; 常富强

    2012-01-01

    Based on related literatures at home and abroad in recent years, novel flotation reagents and process of zinc oxide ore dressing are summarized in this article, which points out that the correct new development direction of oxidized zinc ore flotation research should focus on the study of new high efficiency flotation agents and new flotation process%根据国内外近年来的相关文献,对氧化锌矿新型浮选药剂和选矿新工艺进行了综合评述,认为更有效的新型浮选药剂和浮选流程新工艺的研究是氧化锌矿浮选研究的正确发展方向.

  17. Using statistical experimental design techniques to determine the most effective variables for the control of the flotation deinking of mixed recycled paper grades

    CSIR Research Space (South Africa)

    Pauck, WJ

    2012-01-01

    Full Text Available properties. Samples of newsprint, magazines, and two grades of mixed office waste were pulped and deinked by flotation and washing in the laboratory. Handsheets were formed and measured for brightness, residual ink concentration and yield. A Plackett...

  18. The effect of primary copper slag cooling rate on the copper valorization in the flotation process

    Directory of Open Access Journals (Sweden)

    Aleksandar Mihajlović

    2015-06-01

    Full Text Available Technological procedure of slow cooling slag from primary copper production is applied in the purpose of copper recovery in the level of 98.5% to blister. This technological procedure is divided into two phases, first slow cooling of slag on the air for 24 hours, and then accelerated cooling with water for 48 hours. Within the research following methods were used: calculation of nonstationary slag cooling, verification of the calculation using computer simulation of slag cooling in the software package COMSOL Multiphysics and experimental verification of simulation results. After testing of the experimentally gained samples of slowly cooled slag it was found that this technological procedure gives the best results in promoting growth or coagulation of dispersed particles of copper sulfide and copper in the slag, thereby increasing the utilization of the flotation process with a decrease of copper losses through very fine particles.

  19. Leaching of a copper flotation concentrate with ammonium persulfate in an autoclave system

    Science.gov (United States)

    Deniz Turan, M.; Soner Altundoğan, H.

    2014-09-01

    The leaching behavior of a copper flotation concentrate was investigated using ammonium persulfate (APS) in an autoclave system. The decomposition products of APS, active oxygen, and acidic medium were used to extract metals from the concentrate. Leaching experiments were performed to compare the availability of APS as an oxidizing agent for leaching of the concentrate under atmospheric conditions and in an autoclave system. Leaching temperature and APS concentration were found to be important parameters in both leaching systems. Atmospheric leaching studies showed that the metal extractions increased with the increase in APS concentration and temperature (up to 333 K). A similar tendency was determined in the autoclave studies up to 423 K. It was also determined that the metal extractions decreased at temperatures above 423 K due to the passivation of the particle surface by molten elemental sulfur. The results showed that higher copper extractions could be achieved using an autoclave system.

  20. Effects of Dry Flotation Restricted Environmental Stimulation on Hypnotizability and Pain Control.

    Science.gov (United States)

    Darakjy, Jennifer; Barabasz, Marianne; Barabasz, Arreed

    2015-10-01

    The effects of dry flotation restricted environmental stimulation (REST) on hypnotizability and pain control were tested in lighted and unlighted conditions. Participants (N = 30, ages 18-30) were exposed to hypnosis maximizing (plateauing) experiences prior to the experiment. Participants were exposed to 6 hours of lighted REST (N = 10), 6 hours of unlighted REST (N = 10), or 6 hours of normal stimulation (N = 10). The Stanford Hypnotic Susceptibility Scale: Form C (SHSS: C) (Weitzenhoffer & Hilgard, 1962) and standardized ischemic pain tests were administered before and after the conditions and at a 2-week follow-up. Both REST groups shared significantly higher SHSS: C scores and significantly lower pain scores from pre-test to post-test and follow-up. The lighted REST group showed significantly higher SHSS: C scores and significantly lower pain scores than the unlighted REST group at post-test and follow-up. The findings supported Barabasz's (1982) theory of REST responding.

  1. Leaching of a copper flotation concentrate with ammonium persulfate in an autoclave system

    Institute of Scientific and Technical Information of China (English)

    M Deniz Turan; H Soner Altundoan

    2014-01-01

    The leaching behavior of a copper flotation concentrate was investigated using ammonium persulfate (APS) in an autoclave sys-tem. The decomposition products of APS, active oxygen, and acidic medium were used to extract metals from the concentrate. Leaching ex-periments were performed to compare the availability of APS as an oxidizing agent for leaching of the concentrate under atmospheric condi-tions and in an autoclave system. Leaching temperature and APS concentration were found to be important parameters in both leaching sys-tems. Atmospheric leaching studies showed that the metal extractions increased with the increase in APS concentration and temperature (up to 333 K). A similar tendency was determined in the autoclave studies up to 423 K. It was also determined that the metal extractions de-creased at temperatures above 423 K due to the passivation of the particle surface by molten elemental sulfur. The results showed that higher copper extractions could be achieved using an autoclave system.

  2. Selective factors involved in oil flotation isolation of black yeasts from the environment.

    Science.gov (United States)

    Satow, M M; Attili-Angelis, D; de Hoog, G S; Angelis, D F; Vicente, V A

    2008-01-01

    The oil flotation isolation technique has been successfully applied to recover chaetothyrialean black yeasts and relatives from the environment. The selective mechanisms playing a role in isolation are unknown. The fungi concerned are supposed to occupy specialized microniches in nature, taking advantage of (1) oligotrophism. Mineral oil as a main selective agent may be based on (2) hydrophobicity or on (3) assimilation. All three hypotheses are tested in this paper. Results show that cell wall hydrophobicity is unlikely to be a selective factor. Incubation under poor nutrient conditions provides competitive advantage for black yeasts, especially for Exophiala strains, which are subsequently enriched by mineral oil which enhances growth in this group of fungi. Incubation under mineral media and mineral oil can be used as selective factor.

  3. Bioleaching of marmatite flotation concentrate by Acidithiobacillus ferrooxidans and Leptospirillum ferrooxidans

    Institute of Scientific and Technical Information of China (English)

    石绍渊; 方兆珩

    2004-01-01

    Bioleaching of marmatite flotation concentrate by Acidithiobacillus ferrooxidans and Leptospirillum ferrooxidans was investigated at 35 ℃, the initial pH value of 2.0 on an orbital shaker with 160 min-1 over a period of 10 days. Experimental results indicate that the adapted strains increase markedly the dissolution rate and the leaching ratio of marmatite. Pulp density also affects the bioleaching of marmatite. Massive elemental sulfur and jarosite form during the leaching process in the systems inoculating the adapted strains in pure and mixed cultures; and acid product is enhanced, which decreases the pH below to 2.0 in latter leaching period. Marmatite preferentially dissolves during the bacterial leaching of complex sulfides. Compared with the pure cultures of original and adapted strains, the adapted strains of Acidithiobacillus ferrooxidans and Leptospirillum ferrooxidans in mixed cultures are more efficient in the oxidation of marmatite.

  4. Mechanisms of flotation separation of diaspore and kaolinite by quaternary ammonium salt DTAL

    Institute of Scientific and Technical Information of China (English)

    陈湘清; 胡岳华; 王毓华

    2004-01-01

    The FTIR spectroscopy indicates that the adsorption of quaternary ammonium salt DTAL on the diaspore and kaolinite is physical adsorption. The adsorption of cationic surfactants measured by two-phase titration shows that the adsorption on the kaolinite is notably more than that on diaspore. The adsorption isotherm on kaolinte is linear while that of DTAL on diaspore is two-step flat form. The analysis on the cationic ions of kaolinite supernatants shows that kaolinite releases plenty of crystalloid structure ions which countervail the crystalloid charge because of the adsorption of the cationic surfactant. The mechanisms of the quaternary ammonium salt DTAL on flotation separation of diaspore and kaolinite include ion exchange interaction as well as electrostatic force.

  5. Reverse flotation separation on diaspore and kaolinite in the presence of cationic polyacrylamide polymers

    Institute of Scientific and Technical Information of China (English)

    刘广义; 钟宏; 卢毅屏; 冯其明

    2003-01-01

    Based on the analyses of crystal structures and surface properties of diaspore and kaolinite, an effective diaspore depressant, CPAM(cationic polyacrylamide) polymers was discovered by single minerals tests, separation experiments of artificial mixed minerals, zetapotential and adsorption measurement. The reverse flotation separation on diaspore and kaolinite can be carried out using collector dodecylamine acetate and depressant CPAM under pH 5.5-8.5. On the surfaces of diaspore, there are a large amount of active aluminum atoms. They can bond with-C(O)NH2 groups in CPAM and make the-CH2N+(CH3)3 groups in CPAM orient toward the outer surfaces of diaspore, which prevents a majority of the dodecylamine cations from adsorbing on diaspore, enhances hydrophilicity of diaspore, and depresses the floatability of diaspore. But for kaolinite, CPAM polymers have little effect on its floatability.

  6. A broth-froth recovery seperator application in avermectins production by Streptomyces avermitilis%阻沬回收分离器在阿维菌素发酵中的应用

    Institute of Scientific and Technical Information of China (English)

    武威; 杨励; 郭美锦

    2011-01-01

    Objective To apply a novel broth-froth recovery separator (BFRS) in agro-antibiotic avermectins production by Streptomyces avermitilis on an industrial scale. Method A novel broth-froth recovery seperator,which was made based on the principle of foam cyclone separation coupling with exhauset gas recycling, was introduced in avermectins fermentation. Results The working capacity was significantly increased by 22.47%from 65% (control) up to 80%, resulting in a higher utilization efficiency for the productive fermenter. Also, the total avermectin yield per batch of the fermenter coupling with BFRS was enhanced by 20.54% than the mean monthly avermectin yield per batch obtained without BFRS application. Regarding the exhaust gas recycling performance of the BFRS, 9%~10% of the outlet gas could be reused during avermectin fermentation process, resulting in a significant reduction of total outlet gas emission and of pollutants produced by S. avermitilis cultured in a 120M3 fermenter.Conclusion The BFRS can remarkably enhance the fermenter's working capacity, and it can be applied in other bioproduct production with a similar broth's characterization.%目的:研究一种新型阻沫回收分离器在农用抗生素阿维菌素工业发酵生产中的应用.方法:阿维菌素发酵过程中,应用一种基于泡沫旋风分离与发酵尾气再回收相结合原理的新型阻沫回收分离器.结果:放罐系数由原来月平均的65%提高至80%左右,体积增加率为22.47%,显著提高了发酵罐的利用率;单位罐产量(总亿)比月平均单罐产量提高了20.54%;在发酵过程尾气回收方面,每罐批比对照罐能回收利用9%-10%的排放尾气,减少了发酵污染物的排放.结论:这种新型阻沫回收分离器可显著提高阿维菌素发酵过程中的放罐系数,还可能应用到其它发酵液性能相似的生物发酵产品.

  7. Evaluation of Flotation Collectors in Developing Zero Waste Technology for Processing Iron Ore Tailings

    Directory of Open Access Journals (Sweden)

    R. Suhasini1

    2015-11-01

    Full Text Available Reverse cationic column flotation technology is gaining traction in iron ore processing industry for recovering iron values from iron ore slimes/tailings. Development and selection of appropriate collector suitable to the material to be processed plays vital role in the development of the process/technology. Three cationic collectors which are vegetable oil based, biodegradable and environmental friendly were tested for their efficacy in reducing alumina and silica and improve iron content in the tailings of an operating iron ore washing plant. Selectivity index as defined by Douglas was used as response parameter to measure the efficiency of separation while comparing the performance of these collectors during flotation tests. Sokem 522C proved to be better in comparison to Sokem 701 and Sokem 702 with the highest selectivity index of 20.87. The concentrate generated analyzed 63.30% Fe, 2.20% SiO2 and 2.52% Al2O3 with 69.00% weight recovery and 79.21% Fe recovery from the tailings containing 55.14% Fe, 17.34% SiO2 and 4.04% Al2O3. The concentrate generated is suitable for pellet making due to its attractive granulometry and acceptable levels of alumina content (≤ 2.50% in it. The tailings generated in this process could be utilised for cement manufacturing and tiles or pavement blocks making.The process developed is ‘zero waste’ while mitigating the environmental issues related to managing tailings in iron ore processing plants.

  8. Treatment of oily water by flotation; Tratamiento de aguas oleosas por flotacion

    Energy Technology Data Exchange (ETDEWEB)

    Ortiz O, H.B

    2002-07-01

    The operation of the nuclear power plants such as Laguna Verde (CLV) with nuclear reactors of the boiling water type (BWR) produce radioactive waste solids, liquids and gaseous which require of a special treatment in their operation and arrangement. Such is the case of the liquid wastes from CLV which are a mixture of water and synthetic oils coming from leaks and spilling by pressure of maintenance of electro-mechanical equipment associated to the performance of the nuclear power plant. This mixture of water and spent oils is pretreated by means of sedimentation, centrifugation and evaporation. However the realized efforts by the CLV, the spent oil obtained from the pretreatment contains concentrations of radioactive material higher than the tolerance limits established in the normative in force in radiological safety (0.37 Bq m L{sup -1} for {sup 60} Co and {sup 54} Mn). In this context it was necessary to design an efficient treatment system and economically profitable which separates the oil, the heavy metals and the leftovers of radioactive material that could be present in water, with the purpose of fulfil with the Mexican Official Standards corresponding for its unload or even it can reuse it in the wash process of treated oil. The treatment system of oily water waste consists of: a) Coagulation-flocculation, b) Flotation system with modified air dissolved (DAFm). The proposed flotation process allows to reach a higher separation efficiencies of: Concentration of greases and oils: 94.11 %; Turbidity: 98.6 %; {sup 60} Co: 82.3 % ; Co: 94.8 % and Cr: 99.9 % (Author)

  9. Removal of natural organic matter and arsenic from water by electrocoagulation/flotation continuous flow reactor

    Energy Technology Data Exchange (ETDEWEB)

    Mohora, Emilijan, E-mail: emohora@ifc.org [University of Novi Sad Faculty of Sciences, Department of Chemistry, Biochemistry and Environmental Protection, Trg D. Obradovica 3, 21000 Novi Sad (Serbia); Roncevic, Srdjan; Dalmacija, Bozo; Agbaba, Jasmina; Watson, Malcolm; Karlovic, Elvira; Dalmacija, Milena [University of Novi Sad Faculty of Sciences, Department of Chemistry, Biochemistry and Environmental Protection, Trg D. Obradovica 3, 21000 Novi Sad (Serbia)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer A continuous electrocoagulation/flotation reactor was designed built and operated. Black-Right-Pointing-Pointer Highest NOM removal according to UV{sub 254} was 77% relative to raw groundwater. Black-Right-Pointing-Pointer Highest NOM removal accordance to DOC was 71%, relative to raw groundwater. Black-Right-Pointing-Pointer Highest As removal archived was 85% (6.2 {mu}g/l), relative to raw groundwater. Black-Right-Pointing-Pointer Specific reactor energy and electrode consumption was 1.7 kWh/m{sup 3} and 66 g Al/m{sup 3}. - Abstract: The performance of the laboratory scale electrocoagulation/flotation (ECF) reactor in removing high concentrations of natural organic matter (NOM) and arsenic from groundwater was analyzed in this study. An ECF reactor with bipolar plate aluminum electrodes was operated in the horizontal continuous flow mode. Electrochemical and flow variables were optimized to examine ECF reactor contaminants removal efficiency. The optimum conditions for the process were identified as groundwater initial pH 5, flow rate = 4.3 l/h, inter electrode distance = 2.8 cm, current density = 5.78 mA/cm{sup 2}, A/V ratio = 0.248 cm{sup -1}. The NOM removal according to UV{sub 254} absorbance and dissolved organic matter (DOC) reached highest values of 77% and 71% respectively, relative to the raw groundwater. Arsenic removal was 85% (6.2 {mu}g As/l) relative to raw groundwater, satisfying the drinking water standards. The specific reactor electrical energy consumption was 17.5 kWh/kg Al. The specific aluminum electrode consumption was 66 g Al/m{sup 3}. According to the obtained results, ECF in horizontal continuous flow mode is an energy efficient process to remove NOM and arsenic from groundwater.

  10. What constitutes a convention? : implications for the coexistence of conventions

    OpenAIRE

    Kolstad, Ivar

    2002-01-01

    A model of repeated play of a coordination game, where stage games have a location in social space, and players receive noisy signals of the true location of their games, is reviewed. Sugden (1995) suggests that in such a model, there can be a stationary state of convention coexistence only if interaction is non-uniform across social space. This paper shows that an alternative definition of conventions, which links conventions to actions rather than expectations, permits convention coexistenc...

  11. The Working Principle of Deinked Pulp CPT Flotation Column And Industrialization%脱墨浆渣CPT浮选柱的工作原理及工业化

    Institute of Scientific and Technical Information of China (English)

    孙丽英; 李琼砚; 陈倩

    2011-01-01

    分析了加拿大CPT浮选柱的工作原理、自动控制系统,并分析了脱墨浆渣浮选柱工业化的难点。%Abstract. The thesis discusses the working principle of deinked pulp CPT flotation column, automatic control system, Meanwhile discussing the difficulties in developing industry in deinked pulp CPT flotation column.

  12. Separation of four flavonol glycosides from Solanum rostratum Dunal using aqueous two-phase flotation followed by preparative high-performance liquid chromatography.

    Science.gov (United States)

    Chang, Lin; Shao, Qian; Xi, Xingjun; Chu, Qiao; Wei, Yun

    2017-02-01

    Aqueous two-phase flotation followed by preparative high-performance liquid chromatography was used to separate four flavonol glycosides from Solanum rostratum Dunal. In the aqueous two-phase flotation section, the effects of sublation solvent, solution pH, (NH4 )2 SO4 concentration in aqueous solution, cosolvent, N2 flow rate, flotation time, and volumes of the polyethylene glycol phase on the recovery were investigated in detail, and the optimal conditions were selected: 50 wt% polyethylene glycol 1000 ethanol solvent as the flotation solvent, pH 4, 350 g/L of (NH4 )2 SO4 concentration in aqueous phase, 40 mL/min of N2 flow rate, 30 min of flotation time, 10.0 mL of flotation solvent volume, and two times. After aqueous two-phase flotation concentration, the flotation products were purified by preparative high-performance liquid chromatography. The purities of the final products A and B were 98.1 and 99.0%. Product B was the mixture of three compounds based on the analysis of high-performance liquid chromatography at the temperature of 10°C, while product A was hyperoside after the identification by nuclear magnetic resonance. Astragalin, 3'-O-methylquercetin 3-O-β-d-galactopyranoside, and 3'-O-methylquercetin 3-O-β-d-glucopyranoside were obtained with the purity of 93.8, 97.1, and 99.2%, respectively, after the further separation of product B using preparative high-performance liquid chromatography.

  13. Separation of flue-gas scrubber sludge into marketable products. Third quarterly technical progress report, March 1, 1994--May 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Kawatra, S.K.; Eisele, T.C.; Shoop, K.

    1994-06-01

    Column flotation represents a significant improvement over conventional flotation for many applications. This improvement consists of increased selectivity between hydrophobic and hydrophilic particles, which allows the column to produce higher-purity products. A schematic of the column used is given in Figure 1. The basic procedure for the flotation column experiments was as follows: 500 grams of the sludge from Plant A (prepared as described in the Second Quarterly Report) was suspended at 40% solids in distilled water, to produce 1600 ml of slurry. Reagents were added, and the slurry was agitated vigorously for 1 minute. Frother was added to all of the water to be added to the column, at a rate of 0.03 grams/liter (approximately 0.4 kilograms per metric ton, Kg/mt). The frother used was Dowfroth 200 (a mixture of polypropylene glycol methyl ethers, with a mean molecular weight of 200). The column was started, all of the water flowrates were set as desired, and the drain valve was closed. As soon as the water level had reached the base of the feed inlet tube (approximately 1 minute after closing the drain valve), the 1600 ml feed slurry was added over a 15 second interval. This allowed the feed to be added to the column with a minimum of disturbance to the froth layer, and without causing either surging of the pulp level or large losses to the sinks product. Flotation was carried out for 9 minutes after closing the drain valve. Froth and sinks products were collected, filtered, dried at 45{degrees}C, weighed, and analyzed by thermogravimetic analysis. It is readily seen that, when no collector is added, the column produces a product that is markedly higher purity than that produced by conventional flotation. The addition of oleic acid collector to the column feed is not able to produce any further improvement in product quality, and only results in a loss of product recovery.

  14. Conventional mechanical ventilation

    Directory of Open Access Journals (Sweden)

    Tobias Joseph

    2010-01-01

    Full Text Available The provision of mechanical ventilation for the support of infants and children with respiratory failure or insufficiency is one of the most common techniques that are performed in the Pediatric Intensive Care Unit (PICU. Despite its widespread application in the PICUs of the 21st century, before the 1930s, respiratory failure was uniformly fatal due to the lack of equipment and techniques for airway management and ventilatory support. The operating rooms of the 1950s and 1960s provided the arena for the development of the manual skills and the refinement of the equipment needed for airway management, which subsequently led to the more widespread use of endotracheal intubation thereby ushering in the era of positive pressure ventilation. Although there seems to be an ever increasing complexity in the techniques of mechanical ventilation, its successful use in the PICU should be guided by the basic principles of gas exchange and the physiology of respiratory function. With an understanding of these key concepts and the use of basic concepts of mechanical ventilation, this technique can be successfully applied in both the PICU and the operating room. This article reviews the basic physiology of gas exchange, principles of pulmonary physiology, and the concepts of mechanical ventilation to provide an overview of the knowledge required for the provision of conventional mechanical ventilation in various clinical arenas.

  15. 某硫铁矿矿泥柱浮选半工业试验%Pilot Test of a Pyrite Slime Flotation by Cyclone-Static Micro-bubble Flotation Column

    Institute of Scientific and Technical Information of China (English)

    黄根; 岳双凌; 文涵睿

    2012-01-01

    order to effectively utilize the slime produced in the course of producing - 3 mm production in a pyrite concentrator from Guangdong province,carried out the pilot test of once roughing once cleaning column flotation by two Φ400 mm ×4 000 mm cyclone static micro-bubble flotation columns. Suitable handling capacity,reagent system and circu-lating pump pressure of flotation column were determined by conditions test After 72 h continous production,the S concentrate with 48. 46% grade,93. 71% recovery was achineved,comparing to the spot flotation machine,the S recovery increased by 13 percentage ponits.%为使广东某硫铁矿生产-3 mm产品过程中产生的矿泥得到高效利用,采用2台Φ400 mm×4 000 mm旋流-静态微泡浮选柱在现场对该矿泥进行了1粗1精柱式浮选半工业试验.首先通过条件试验确定了合适的处理量、药剂制度以及浮选柱中矿循环泵压力,然后进行72 h连续运转,获得了硫精矿硫品位为48.46%、硫回收率为93.71%的良好指标.与现场采用浮选机的选别指标相比,硫回收率提高了约13个百分点.

  16. ESD and the Rio Conventions

    Science.gov (United States)

    Sarabhai, Kartikeya V.; Ravindranath, Shailaja; Schwarz, Rixa; Vyas, Purvi

    2012-01-01

    Chapter 36 of Agenda 21, a key document of the 1992 Earth Summit, emphasised reorienting education towards sustainable development. While two of the Rio conventions, the Convention on Biological Diversity (CBD) and the United Nations Framework Convention on Climate Change (UNFCCC), developed communication, education and public awareness (CEPA)…

  17. Study on pilot experiment of selective copper flotation by cyclone static micro- bubble flotation column%旋流-静态微泡浮选柱部分优先选铜半工业试验研究

    Institute of Scientific and Technical Information of China (English)

    邓小伟; 李延峰; 王永田; 程敢

    2011-01-01

    The cyclone static micro-bubble flotation column is a kind of new facility for mineral separation. In order to improve the productivity of a high silver-content metallic ore and reduce the pressure of posterior operation, the pilot experiment of selective copper flotation is carried out by using the cyclone static micro- bubble flotation column. Through the process of single-stage roughing and two-stage cleaning, the grade of copper, gold, sliver reach 18%, 60 g/t, 6 000 g/t, and the recovery rate reaches above 50%. It provides foundations for the production and the technical improvement in enterprises.%旋流-静态微泡浮选柱是一种新型选矿设备,为了提高某银多金属矿生产效率,减小后续作业压力,采用该浮选柱进行了部分优先选铜半工业试验。通过一粗两精闭路流程试验研究,可得到铜、金、银品位分别为18%、60g/t、6000g/t,回收率50%以上的结果,为企业生产和技术改造提供了依据。

  18. Culture-independent qunatification of Salmonella enterica in carcass gauze swabs by flotation prior to real-time PCR

    DEFF Research Database (Denmark)

    Löfström, Charlotta; Schelin, Jenny; Norling, Börje;

    2010-01-01

    , for culture-independent quantification of intact Salmonella in pig carcass gauze swabs (100 cm2) prior to quantitative PCR (qPCR). A novel approach was investigated, excluding the homogenization step prior to flotation, to improve the detection limit and speed up the quantification procedure. The buoyant....... The method allowed accurate quantification from 4.4×102 to at least 2.2×107 CFU Salmonella per swab sample using qPCR (without preceding DNA extraction) or selective plating on xylose lysine deoxycholate agar. Samples with 50 CFU could be detected occasionally but fell outside the linear range...... of the standard curve. The swab samples showed a broad biological diversity; for seven samples not inoculated with Salmonella, the microbial background flora (BGF) was determined to 5.0 ± 2.2 log CFU/ml sample withdrawn after flotation. It was determined that the proceeding PCR step was inhibited by BGF...

  19. Reliability of gas holdup measurements using the differential pressure method in a cyclone-static micro-bubble flotation column

    Institute of Scientific and Technical Information of China (English)

    Xia Wencheng; Yang Jianguo; Wang Yuling

    2011-01-01

    Gas holdup iS one of the Key parameters in flotation process.Gas holclup as measured by a differential pressure method was investigated and the relative errors compared to the average gas holdup from the volume expansion method.The errors were used to establish optimum measurement positions.The results show that the measurement position should be in the middle of the column and in the region half way from the center to the wall (the half-radius).The gas holdup along the axial direction is lower at the bottom and higher at the top of the floatation column.The gas holdup along the radial direction is lower near the wall and higher near the center of the flotation column.The average gas holdup measurement can be replaced bv regional gas holdup values.

  20. Effectiveness of hand sorting, flotation/washing, dehulling and combinations thereof on the decontamination of mycotoxin-contaminated white maize.

    Science.gov (United States)

    Matumba, Limbikani; Van Poucke, Christof; Njumbe Ediage, Emmanuel; Jacobs, Bart; De Saeger, Sarah

    2015-01-01

    Maize is one of the major staple foods of Sub-Saharan Africa and is consumed as whole or dehulled grain. In this region, where the environmental conditions favour fungal growth and mycotoxin production, the majority of the population are subsistence consumers who, unfortunately, have little or no access to mycotoxin testing of their food. In an attempt to develop feasible reduction strategies in dietary mycotoxin exposure of the population, a three-factorial design experiment was conducted to examine and compare the efficacy of hand sorting, flotation, dehulling and combinations thereof in removing naturally occurring aflatoxins, fumonisins, nivalenol, deoxynivalenol and alternariol in shelled white maize. Regression analysis was used to determine the significant (p mycotoxins from the maize. Results from this experiment indicated that hand sorting had the greatest effect on mycotoxin removal, while flotation yielded the least effect. In particular hand sorting left mycotoxin exposure among subsistence consumers.