超声波预处理对稀缺难浮煤浮选的作用

The effect of ultrasonic pretreatment on the flotation of scarce difficult-to-float coals

为提高稀缺难浮煤的浮选效果,引入超声波对稀缺难浮煤矿浆进行预处理,利用Setar-amC80Ⅱ型微量热仪、DCAT21型接触角测定仪和752型可见光光度计研究了超声波预处理后的矿浆的浮选过程.结果表明:当超声波频率为40kHz,矿浆预处理4min后浮选,精煤灰分大致相同时,精煤产率、浮选完善指标和可燃体回收率分别比未经预处理的提高了19.47%,18.80%和24.14%.预处理促进了煤粒与矸石的解离,煤泥的粒度变细;超声波预处理使煤泥的疏水性增强,不同粒级煤泥与水的润湿热以及对煤油的吸附量均有不同程度的降低,煤与水的接触角有不同程度的升高.超声波预处理能提高稀缺难浮煤的浮选效果.

For improving the flotation efficiency of scarce difficult-to-float coals,the scarce difficult-to-float coal slurry was pretreated by ultrasonic.The flotation process of coal slurry was investigated using Setaram C80Ⅱ micro calorimeter,DCAT21 type contact angle measurement and 752-type visible light photometer.The results show that the yield of clean coal,flotation perfect indicators and recovery of combustible matter are improved by 19.47%,18.80% and 24.14% respectively under the ultrasonic frequency of 40 kHz,pretreatment time of 4 min and the similar coal ash,compared with that under no ultrasound pretreatment.The ultrasonic pretreatment promotes the dissociation of the coal particles and gangue,and the size of coal slime became finer.The hydrophobic of slime pretreated by ultrasonic pretreatment was enhanced.The wetting heat of different size fractions of slime and water as well as the kerosene adsorption amount is reduced in its varying degree,and the contact angle of coal-water increase in different degrees.The ultrasonic pretreatment can improve the flotation effect of the scarce difficult-to-float coals.