Experimental Studies Of Separating Feature And Reagent Optimization Of Coal Slime

As the place of origin and flotability of coal slime were changing, lots of practical problems were existing in coal flotation collectors, for example, it was difficult to disperse in coal pulp, it need a large consumption, its selectivity was poor,and separating efficiency was low. In this paper, experimental studies of the flotation reagent optimization were conducted based on the characteristics of coal slime, the basic flotation characteristics of the coal slime were analysised by flotation tests, impact of various surfactants to collector performance were studied, the surfactants with a great effect were elect out for compound, and then the compound surfactants were used for optimizing folotation collector, and so a better somposite collector was got. The flotation characteristics of the coal under different flotation conditions were studied too, and the surface properties of coal slime were tested. And suitability of the composite collector were tested by a different coal slime, such following results were got from the experimental study:(1) The coal slime was low-middle ash, middle-high fixed carbon, low sulfur coal, according to the proximate analysis, sulfur grading test, the relative contact angle of the coal slime was 74.06°, hydrophobicity of the Coal Slime surface was strong; and Zeta potential of the Coal Slime was -29.8142mv.(2) When meeting the requirements of 10.00% ash content of clean coal, the amount of kerosene was 900g/t, and the amount of octanol-2 was 450g/t, yield of clean coal was 88.67%, combustible recoveries was 94.69%.(3) Effects of different surfactants to collector flotation results were different, Tween-20 non-ionic surfactant and 1231 cationic surfactant had no promote effect to flotation collector, non-ionic surfactant Tween-60, Tween-80, Span-80, AEO-9; anionic surfactant AESS and amphoteric surfactants BS-12 had a good role in promoting the flotation collector effect.(4) When the HLB value of compound surfactant was 7.0, and dosage was 1.0%; The ST-1 composite collector was iconfigurated by compound surfactant, and while the unit dosage of it was 500g/1, the unit dosage of Octanol-1 was 450g/t, clean coal ash of flotation was 9.97%, yield of clean coal was 88.72%, combustible recoveries was 94.82%; in the same request of clean coal ash,the ST-1 composite collector can save 44.44% of the amount of flotation collector.(5) The ST-1 composite collector can adapt to changes of the coal slurry concentration better than general collector, time of collector impacted the ST-1 composite collector littly; and the ST-1 composite collector had a better selectivity for the coal clime which was samller than 0.075 mm.(6) The clotation effect were different with different collector ftotation, while the ST-1 Composite Collector compared to general collector, relative contact angle of slime surface increased much significantly, absolute value of coal slime Zeta potential were decreased, the ST-1 composite collector can improve hydrophobicity of coal slime particles better, and strengthen flotability of coal slime particles.