Experimental Study On Ultrasonic Enhancing The Flotation Of The Scarce Difficult-to-float Fine Coals

With the rapid development of the national economy, the consumer demand for coal in the country has increased year by year. Although the coal resources is rich, but the scarce coal content for cooking such as cooking coal and fat coal is less, thus enhancing its mining recovery at the same time, the washed coal recovery should be increased. Therefore, aimed at the increasing scarcity of difficult floated coal of floatation, it has been pressing to improve the quality of the scarce coal by flotation method. In the flotation method of physical conditioning, the ultrasound can not only improve the quality of selected slime , but also improve the efficiency of coal flotation. In this paper, the ultrasonic has been carried out enhancing the flotation of the scarce difficult to float fine coals. This paper is mainly devoted to study on scarce fat coal in Tangshan, Hebei Zhaogezhuang Bureau of Mines. It selects kerosene and octanol as a flotation reagent, and introduces the orthogonal experiment on the ratio of the two factors and the total volume of four levels. Choosed 25,35,40 kHz frequency ultrasound head, this paper contrasts the three tests. The experimental results show that collector and frother ratio is 1﹕3, collector and frother for the total volume is 1.53 kg / t, the best ultrasonic time is 3 min or 4 min, process II is the best ultrasonic flotation technology.To explore the ultrasound enhanced floating scarce hard coal flotation mechanism, this paper studies the ultrasonic treatment of slurry particle size, wettability of coal and hot water, tap water, tap water + collector, tap water + collector + frother agents and after 40 kHz ultrasonic treatment 4 min after the water surface tension and collector adsorption in the coal surface impact. Analysis results show that ultrasonic fragmentation of coal particles has changed the role of the size of coal particles to coal and pyrite, gangue dissociation; a level with the ultrasound treatment before the wetting heat treatment than ultrasound after wetting hot big; ultra - sound water treatment reached at add tap water collector and frother agent to reduce gas-liquid surface tension of the same effect; ultrasound treatment for each class a hydrophobic coal particles have been improved, oil droplets in the strong hydrophobic more spread out the surface, improve the utilization of the oil droplets, thereby reducing drug consumption, improve the effectiveness of the flotation. From the cost-effectiveness analysis, ultrasound treatment to the floating per- tonne in Tangshan Zhaogezhuang slime increase 175.59 yuan than conventional flotation, the economic benefits is significantly.