Gas dispersion measurements in coal flotation cells. January 2006

oil on flotation response of low rank coal was investigated at different conditioning times. Additionally, Fourier transform infrared spectrometer, specific surface area analyzer, scanning electron microscopy, and contact angle measurements were used to determine the properties of coal and flotation of coal slime

Experimental measurements (polarized optical microscopy, zeta potential, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, contact-angle analysis) were used to explore the influence of OPS in low-rank-coal flotation.

The original LRC sample was used as the feed of the flotation while the clean coal sample was used for FTIR measurements and contact angle tests. The feeding rate of dodecane was 0.015 mL/min. The dodecane dosages were 1 kg/t, 2 kg/t, 4 kg/t, and 6 kg/t.

predicting coal flotation collectors. In order to obtain this, it is necessary to perform contact angle measurements on coal samples and to test the results against batch scale flotation performance. 2. EXPERIMENTAL 2.1. Sample preparation Representative coal samples were obtained from the Waterberg coal field (South Africa) and seam 2 and

Measurementsofwholecoals both in water and withsurfactants showedthezero point of charge (zpc)to be in the range of 4 to4.5fortheIllinoisNo. 5 (Springfield-SE) sample,

Jul 11, 2018· The hydration film on particle surface plays an important role in bubble-particle adhesion in mineral flotation process. The thicknesses of the hydration films on natural hydrophobic coal and hydrophilic mica surfaces were measured directly by atomic force microscopy (AFM) based on the bending mode of the nominal constant compliance regime in …

unexpectedly these tests indicated that aluminum nitrate may be an activator for coal because it served to increase the recovery of coal. Several potential flotation depressants for pyrite have been screened by measurement at the zeta potential and floatability of pyrite or coal in aqueous suspensions containing the potential depressants.

Coal flotation circuits for tlIch separations are becoming more important in the processing 411=:-690/AID : (-28 mesh) coal (Miller, Podgursky, and Aikman, Aplan. 1979; and Burger. 1980). For example in the US in,81 flotation plants processed 24 kt/d (26.500 tpd); whereas ~980, there were 80 flotation plants which processed 71 kt/d

World coal production is likely to increase at least 2.5-3.0 times in the corning two decades (Konar, 1982). Although coal reserves are large in comparison with other fossil fuels and coal is expected to play an important role as a future energy source, the present world recession and

Experimental measurements (polarized optical microscopy, zeta potential, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, contact-angle analysis) were used to explore the influence of OPS in low-rank-coal flotation. Poor flotation performances of coal samples were received using OPS or DO as collectors at an economical ...

May 21, 2007· Abstract. Results obtained from batch flotation experiments on seven coal samples, having widely varying size and size-wise ash distributions have been used to develop a simple empirical model for predicting the performance through first order kinetic behaviour.

Contact angle measurements and electron probe microanalyzer micrographs indicate that the deposition of hydrophobic nanoparticle on coal surface increased the hydrophobicity and microscale roughness of coal particles, which was beneficial to flotation process. Although the current nanoparticles used were effective for coal flotation, the dosage ...

Feb 01, 1994· Several nonionic surfactants and one anionic surfactant were tested to enhance the flotation response of a low-rank coal. The nonionic surfactants included an ethoxylated octyl phenol and several polypropylene-polyethylene block copolymers, and the anionic surfactant was a dioctyl sulfosuccinate. All of the surfactants improved the yield significantly, but the influence …

For measurement difficulties the solids concentration was kept at 1.0% in this test. If the concentration of coal in the flotation pulp were around 5% as is the case in coal flotation practice, the aggregation should be expected to be much more severe.

flotation collector for low-rank coal and found that the flotation recovery of low-rank coals using the mixture of candle soot and dodecane were higher than that using solo dodecane as collector [17]. Atesok and Celik found that the flotation behavior of low-rank coal was obviously improved using dry grinding method with colloctor [18].

The role of Al-PAM in fine coal flotation was fundamentally explored by examining the surface properties of raw coal and froth after polymer-assisted flotation. Zeta potential measurements were conducted for clean coal (4% ash), raw coal and concentrates from froth flotation experiments in the absence or presence of Al-PAM.

Coal flotation across the world has undergone major changes over the past thirty years. In a number of new coal flotation plants, the traditional mechanical flota-tion cells have been replaced by pneumatic flotation cells, such as the Jameson Cell and Microcel column cells. Significant steps have also been taken in the under-standing of what happens "beneath the …

S. Castro, J.S. Laskowski, in Minerals Engineering, 2015 3 Effect of flocculants on coal flotation. This important aspect of coal flotation has been extensively discussed in the book by Pikkat-Ordynsky and Ostry (1972).In their tests they used slightly anionic polyacrylamide (PAM) with molecular weight of 3 × 10 6 and non-ionic polyethylene oxide (PEO) with molecular weight of …

A quantitative approach was adapted to correlate the flotation response and the quantity of hydrophobic and hydrophilic groups in coal as determined by infrared measurements. It is shown that the amount of hydrophobic and hydrophilic groups in coal dictates whether a particular coal is conductive to thermal treatment prior to flotation.

Keywords: flotation, hydrophobicity, low rank coal, Tween 60, pretreatment Introduction Flotation is widely used in beneficiation of fine coal slimes (<0.5 mm) and is based on the difference in hydrophobicity between coal matter and minerals. It is well known that coal particles are usually much more hydrophobic than gangue ones (Drzymala, 2007).

Abstract. The primary goal of this project is to develop advanced flotation methods for coal cleaning in order to achieve 90% pyritic sulfur removal at 90% Btu yield, 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. Investigation of mechanisms for the control ...

Zeta PoteDtJal Measan8e8t. Coal slurries uaed in the.ta potential measurements were prepared using a procedure 8imi]ar to that used in flotation experiments except that a 0.1 wt % coe.l slurry W88 uIed here. After conditioning, approximately 25 em' of the slurry was transferred into the sample cell of a Lazer Zee

Froth flotation is used for the finer-sized fractions of coal. Up to 40% of the coal may be concentrated by flotation [ 1 ], a figure that may be as low as 10% in Australia [ 2 ]. It is believed that the proportion of coal concentrated by flotation is increasing with the increasing mechanisation of mining.

Reagent flow for flotation control In hard coal flotation, reagents are required to improve the recovery rate of coal from the other mineral substances, such as sulphur, and to improve the froth structure. Accurate flow measurement is important because the chemicals are costly. In addition, valuable end product

Jan 15, 2018· Before the flotation tests, the low rank coal sample was agitated in a 100 mL beaker for 5 min with 80 mL of the corresponding surfactant solution. The amount of low rank coal was 3.0 g in each flotation measurement while the air flow rate was set to 1.0 mL/min. 3. Results and discussion3.1. XPS analysis

By combining experimental results from Hallimond-tube and bench-scale flotation experiments, bubble attachment-time measurements, wetting phenomena, and FTIR spectroscopy, it is clear that thermal treatment under the above conditions, which involves dehydration and oxidation reactions, changes the coal sample to a more hydrophobic state.

Slime coating is known to be one of the detrimental effects of clay in coal flotation. In this study, the viscosity measurements of coal-clay mixture suspensions and corresponding batch flotations ...

further proceeded, is about 15% of the total coal washing amount, while the flotation amount of coal slime is about 0.33 billion tons (Pg). Therefore, the diesel demand for coal flotation is about 0.3 Tg which leads to a huge petroleum consumption, and also increase the production costs of coal preparation (Yi et al., 2015).

The froth flotation of coal is conducted in the presence of a conditioner of an oxygen containing compound of the formula: R.sub.1 --O--R.sub.2).sub.n (I) wherein R 1 and each R 2 are independently saturated hydrocarbyls and n is from 1 to about 3.

A detailed research effort on the fundamentals of coal flotation by carbon dioxide was initiated. Research has been carried out on different aspects of the problem including hydrophobic characterization, bench-scale flotation, carbon dioxide adsorption, electrokinetic behavior, and FTIR spectroscopy for coals of different rank.

POLYACRYLAMIDES IN FINE COAL FLOTATION By ONTLAMETSE KENNETH MOLATLHEGI A THESIS Presented to the faculty of Graduate school of the ... Zeta potential measurements for raw coal at natural pH ..... 61 Figure 4.8. Zeta potential measurements for froth of Al-PAM with Dispersant ..... 61 Figure 4.9. ...