Coal flotation

Pressure filters can treat feeds with concentrations up to and in excess of 10% sohds by weight and having large proportions of difficult-to-handle fine particles. Typically, slurries in which the sohd particles contain 10% greater than 10 ]lni may require pressure filtration, but increasing the proportion greater than 10 ]lni may make vacuum filtration possible. The range of typical filtration velocities in pressure filters is from 0.025 to 5 m/h and dry sohds rates from 25 to 250 kg nY/h. The use of pressure filters may also in some cases, such as in filtration of coal flotation concentrates, eliminate the need for flocculation. 

The KDF Filter. The KDP filter (Pig. 23) (Amafilter, Holland) is based on the same principle as disk filters. It was developed for the treatment of mineral raw materials, like coal flotation concentrates or cement slurries, and can produce a filter cake of low moisture content at very high capacities, up... 

Fig. 14. Coal flotation flow sheet suggested for increased sulfur removal (29). Pyritic sulfur removal from coal makes it imperative to closely control pulp...

Sulfide collectors ia geaeral show Htfle affinity for nonsulfide minerals, thus separation of one sulfide from another becomes the main issue. The nonsulfide collectors are in general less selective and this is accentuated by the large similarities in surface properties between the various nonsulfide minerals (42). Some examples of sulfide flotation are copper sulfides flotation from siUceous gangue sequential flotation of sulfides of copper, lead, and zinc from complex and massive sulfide ores and flotation recovery of extremely small (a few ppm) amounts of precious metals. Examples of nonsulfide flotation include separation of sylvite, KCl, from haUte, NaCl, which are two soluble minerals having similar properties selective flocculation—flotation separation of iron oxides from siUca separation of feldspar from siUca, siUcates, and oxides phosphate rock separation from siUca and carbonates and coal flotation. 

Hart G, Morgan S, Bramall N, Nicol S (2002) Enhanced coal flotation using picobubbles. CSIRO Report-C9048, Australia... 

In on effort to establish the mechanism of coal flotation and thus establish the basis for an anthracite lithotype separation, some physical and chemical parameters for anthracite lithotype differentiation were determined. The electrokinetic properties were determined by streaming potential methods. Results indicated a difference in the characteristics of the lithotypes. Other physical and chemical analyses of the lithotypes were mode to establish parameters for further differentiation. Electron-microprobe x-ray, x-ray diffraction, x-ray fluorescent, infrared, and density analyses were made. Chemical analyses included proximate, ultimate, and sulfur measurements. The classification system used was a modification of the Stopes system for classifying lithotypes for humic coals. 

P. K. Naik, P. S. R. Reddy, and V. N. Misra, Interpretation of interaction effects and optimization of reagent dosages for fine coal flotation. Internal. J. Mineral Processing 75(1-2) (2005). 

Hussain, S.A., Demirci, S. and Ozbayoglu, G., Zeta potential measurements on three clays from Turkey and effects of clays on coal flotation, J. Colloid Interf. Sci., 184, 535, 1996. 

TREATABILITY/REMOVABILITY Process, Removable Range (%), Avg. Achievable Cone. (pg/L)) Coal flotation with chemical addition (calcium chloride polymer), 76, 260 Filtration, 50->94, 3.8 Sedimentation with chemical addition (alum, lime), >99, <0.05 Sedimentation with chemical addition (alum), 25->50, <12 Aerated lagoons, >96, <10 Granular activated carbon adsorption, >99, <0.05 in a continuous flow activated sludge system, about 100% removal (78% biodegradation, 22% stripping) was reported... 

Coal Preparation TABLE V Coal Flotation Reagents 95... 

Adapted from Klassen, V. I. (1963). Coal Flotation, Gogortiekhizdat, Moscow. (In Russian.)... 

Insolubility of the collector in coal flotation requires prior emulsification or long conditioning time. On the other hand, the time of contact with the frother should be as short as possible to avoid unnecessary adsorption of frother by highly porous solids, such as coal. 

As in coal flotation, oil agglomeration takes advantage of the difference between the surface properties of low-ash... 

Coal flotation is a physiochemical process which exploits the differences in the wettability of hydrophobic clean coal and that of hydrophilic foreign particles (Arnold and Apian, 1989 Fecko et al., 2005). It is, therefore, subject to the surface properties of coal pyrite and other types of commercially worthless material present in coal which plays a major role in determining separation of such material from coal (Luttrell and Yoon, 1994 Luttrell et al., 1994). 

Apian, F.F. 1993. Coal properties dictate coal flotation strategies. Mining Engineering, 45 83-96. 

Fonseca, A.G., Meenan, G.R, and Oblad, H.B. 1993. Automatic control coal flotation and dewatering processes. Coal Preparation, 17 73-83. 

Banford, A.W., 1996, The Use of Off-line Image Analysis in Assessing The Effect of Various Reagent Addition Strategies on the Performance of Coal Flotation in a Batch Cell, PhD Thesis, The University of Manchester, U.K. 

Positive displacement slurry pumps are used in a number of industries (Table 9-1). Solid piston pumps are reserved for the pumping of slurries of a low to medium abrasiveness (Miller Number <50) such as chalk slurry, fine coal, flotation material, and driUlng mud sludge. 

Yi, Q., et al., 2015. S3Tithesis of S04 /Zr-SBA-15 catalyst for the transesterification of waste cooking oil as a bio-flotation agent in coal flotation. Fuel 143,390—398. Available at http // www.sciencedirect.eom/science/article/pii/S0016236114011697 (accessed 11.05.15.). 

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