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The flotation-flocculation mineral experiment was conducted to float clean coal from Huo shi zui fine coal in Bin chang mining area with high ash and high sulfur content. This paper studied the factors that influenced the clean coal ash and sulfur content. These factors above were as follows: raw coal quality, coal slurry concentration, reagent system, technological process, and flocculant agents. Take the step by step release deashing process for flotation clean coal. The effects of coal particle size (A), concentration of coal slurry (B), collecting agent (C), frothing agent (D) and agitating speed (E) on the yield of fine coal, ash and sulfur content were investigated. According to the orthogonal experiment with the previous factors, the primary sequence affecting the yield of fine coal is : D>E>C>A>B, and the optimum operation conditions are determined to be A2B4C1D3E3, which are 0.125-0.074mm, 60g/L, 1.73g/kg(kg represents the weight of coal sample on the air dried basis, the same as below), 0.18g/kg, 2000r/min, respectively, with the yield of clean coal 38.26%, ash 3.52% and sulfur content 0.34%.On the base of determine the optimum combined conditions of flotation process, further to investigate the emulsified collector and flotation - flocculation combined process in mineral-processing. The results showed that using sodium dodecyl sulfate as the emulsified collector had the best effect on emulsify. When oil-water ratio is 1/1, the yield of clean coal 61.59%, the ash 4.21%, sulfur content 0.43%, and fuel saving rate 50%.In the flotation- flocculant experiment, selecting four different flocculant agents respectively and the cationic polyaluminium chloride had significant effect. The flotation- flocculant experiment and flotation experiment indicated that when the cationic polyaluminium chloride dosage was 0.1g/kg, the yield of clean coal was 42.15% which increased 0.89%; the ash was 2.96% which reduced 0.56%; the sulfur content was 0.31% which decreased 0.03%. The perfection index is 46.98%, the combustible material rrecovery is 52.58%, the fuel saving rate is 50%.The optimum operation conditions are finally determined by process optimization, the coal particle size is 0.125-0.074mm, coal slurry concentration is 60g/L, emulsified collector (the collector is emulsified by sodium dodecyl sulfate ) is 0.865kg/t, frothing agent is 0.18g/kg, flocculant dosage is 0.1g/kg, the agitating rate is 2000r/min, obtained the low ash and sulfur content clean coal with the yield 42.15%, the ashcontent decreased from 22.21% to 2.96% ,the sulfur content decreased fom 2.07% to 0.31%.This paper studied the deashing and desulfurization process of Bin chang fine coal with flotation process, collector emulsification and adding flocculant, which provide reliable theoretical and practical basis for washing processing of Bin chang fine coal.
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