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Showing 1 to 20 of 30 for “"column flotation"”.
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Scale-up of column flotation
The parameters controlling column flotation have been investigated using laboratory and pilot-scale flotation cells. It was determined that column recovery is a function of flotation rate constant, axial dispersion, retention time and fractional air hold-up within the cell. Mathematical expressions …
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Simulation of computer control strategies for column flotation
… to obtain mathematical expressions relating column flotation operating parameters. The empirical data were derived by making individual step changes in tailings rate, wash water rate, feed rate, frother addition and air rates, while measuring the pulp level and air holdup responses. The …
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Continuous column flotation of ultrafine coal using microbubbles
A flotation column has been developed Incorporating the use of fine air bubbles (less than 100 microns) to remove ash-forming minerals from micronized coal. The microbubble generator used In this work has been characterized and found to yield a very narrow size distribution. Microbubble column …
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Parametric study and simulation of microbubble column flotation
… 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 …
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An investigation into column flotation of South African coals
… the -150 μm fraction) particles achievable with column flotation technology is well established. The principal aim of this thesis is to investigate whether column flotation can be used to recover saleable, particularly low-ash quality, coal from South African coal fines which are presently …
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Processing of high-sulfur coals using microbubble column flotation
… problem. In this investigation, the microbubble column flotation process (MCF), developed at VPI&SU, was tested as a means of reducing the pyritic sulfur content of several high-sulfur coals targeted by the u.S. Department of Energy. A wide variety of pyrite rejection schemes were tested …
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Evaluation of column flotation circuits for fine coal cleaning
… arrangements that may be used to improve the column flotation of micronized coal. Laboratory flotation tests were performed with two different samples of Pittsburgh No. 8 seam coal. The first coal, Coal A, was ground to two different particle sizes and subjected to both column and conventional …
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Optimization of Air-injection Spargers for Column Flotation Applications
Column flotation cells have become the most popular machine designed for industrial applications that require the separation and concentration of wanted or unwanted minerals from the rest material associated in a pulp. To achieve this process separation an air sparging device, which is required to …
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Characterization and scale-up of microbubble generation in column flotation
… can be used to improve the performance of column flotation. Tests carried out at Virginia Tech during the past several years have shown that various types of inline motionless (or static) mixers can successfully produce microbubbles for column flotation. Unfortunately, few guidelines exist …
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A Comprehensive Dynamic Model of the Column Flotation Unit Operation
The core of this project was the development of a column flotation dynamic model that can reasonably predict the changes in the concentrations of all solid and bubble species, along the full column height. A dynamic model of a process is normally composed of a set of partial or ordinary …
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Redesign of Industrial Column Flotation Circuits Based on a Simple Residence Time Distribution Model
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. …
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The determination of the effects of physical and chemical parameters on the column flotation cell, performance in the flotation of pyrite
This masters dissertation an column flotation is to determine the effects of physical and chemical parameters on the column flotation cell performance in the flotation of pyrite. Hypotheses are also proposed to explain observed changes. Chapter one gives a brief description of flotation columns, …
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Optimum Processing of 1 mm by Zero Coal
… plant efficiencies by processing coarser coal in column flotation than is now commonly treated by that method. Column flotation for coarse coal is supported by actual lab and plant test data that result in a full-scale column plant installation. The fundamentals of coarse particle detachment from …
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Bubble Size Effects in Coal Flotation and Phosphate Reverse Flotation using a Pico-nano Bubble Generator
Froth flotation is widely used in minerals industry. However, it is effective in a narrow size range, nominally 45--250 mum for coal and 10--150 mum for minerals. And the flotation performance of coal and minerals beyond this size range is not quite satisfactory. It is now recognized that the …
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Precombustion desulfurization of coal by photochemical methods and pyrite depression in froth flotation
… of a novel pyrite depressant in froth flotation. Semiconductor photoelectrochemical catalysis was extensively examined. As much as 41% of the organic sulfur was removed and 72% overall desulfurization of micronized Illinois No. 2 coal was obtained. Zinc oxide, in colloidal suspension, …
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Fine particle flotation for Florida dolomitic phosphate pebbles
… was processed using a 1.2 liter stirrer-tank flotation cell and 2-in ID packed flotation column aiming at achieving a phosphate concentrate containing more than 30% P2O 5 and less than 1.0% MgO contents at high P2O5 recovery.;The characteristics of fatty acid collector, FA-12 and a newly …
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An In-Plant Evaluation of Froth Washing on Conventional Flotation Cells for Coal
Column flotation cells have become increasingly popular in the coal industry due to their ability to improve flotation selectivity. The improvement can be largely attributed to the use of froth washing, which minimizes the nonselective entrainment of ultrafine minerals matter into the froth …
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Evaluation of an advanced fine coal cleaning circuit
… a surface-based separator known as Microcel™ column flotation with an enhanced gravity separator known as the Multi-Gravity Separator (MGS). The synergistic effect of combining both processes in a single circuit resulted in improved ash and pyritic sulfur rejection with minimal losses in …
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Development of a Novel Air Sparging Device
Column flotation is commonly employed in the processing and recovery of fine mineral particles due to an increase in flotation selectivity unattainable using conventional flotation methods. Such an increase in selectivity is due to the employment of wash water, minimizing hydraulic entrainment of …
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