随着低阶煤开采量和采煤机械化程度的增加，低阶煤泥产量和灰分也不断增加，导致大量的低阶煤煤泥无法回收利用，造成资源浪费和环境污染问题。超声浮选结合了多种调控方法处理低阶煤，能够有效提高选择性及浮选效果。通过高速摄像系统，揭示了驻波声场中的气泡聚集过程及该过程的带煤情况，探究了驻波声场中的微泡产生及其作用,结合驻波声场中微泡附着的选择性探究和柱选试验结果，研究了100 kHz驻波超声对柱选的影响，分析了驻波声场在整个柱选过程中的作用。结果表明:将驻波超声加入柱选后，可以强化低阶煤煤泥柱选效果。精煤产率、可燃体回收率和浮选完善指标分别达到了21.93%，30.52%和23.77%，均高于常规柱选，精煤灰分为11.13%，比常规柱选低1.07%。驻波声场中的气泡有规律地聚集，在趋于稳定后，气泡聚集体以条纹状聚集态分布在整个驻波声场中,气泡聚集是驻波声场与扩散声场最明显的区别。声场驱动力提供了能量，促进了煤颗粒与气泡之间的碰撞。微泡可作为煤颗粒与其他气泡之间的“介质”，在很短的时间内促进气泡聚并，形成煤-泡聚集体，且该过程具有一定选择性。煤-气泡聚集体的形成提高了精煤产率、可燃体回收率和浮选完善指标。

With the increase in coal mining volume and mining mechanization,the yield of low rank coal slime and its ash content increase,which result in some environmental problems and that large amount of low rank coal slime is difficult to be recycled.Ultrasonic flotation is a method that combines various adjustments,which can improve the flotation selectivity and recovery of coal washed.In this study,the processes of bubble aggregation and coal-bubble aggregation were revealed by a high-speed camera system.The processes of generation,effect and selection of microbubble were explored.Combined with the column flotation results and selective exploration of micro bubble in standing wave field,the effects of the 100 kHz standing wave ultrasound on flotation column was investigated and the influence of the standing wave in the column flotation process was analyzed.The results showed that the clean coal yield (21.93%),combustible recovery (30.52%) and flotation improvement index (23.77%) of ultrasonic column flotation were higher than conventional column flotation.The ash content of clean coal was lower than that of conventional column flotation.The bubbles in the standing wave field gathered regularly.After a few times,the bubble aggregates distributed in the whole standing wave field as stripes.This process was the biggest difference between standing wave ultrasound and diffusion ultrasound.The energy generated by ultrasonic standing waves improved the attachment efficiency between fine particles and microbubbles.The microbubbles acted as a “medium” between fine particles and other bubbles to promote their coalescence and form aggregates at a very short time.These coal-bubble aggregates had a favorable effect on flotation.

1 试验部分

   1.1 试验煤样

   1.2 试验装置

   1.3 试验方法

2 结果与讨论

   2.1 驻波超声柱选试验结果

   2.2 驻波声场中的气泡行为

   2.3 驻波声场中微泡的产生及其作用

   2.4 驻波声场中微泡附着的选择性

3 结论