Abstract Bubble-particle detachment is the main factor to limit the recovery of coarse particle in flotation. A dynamic interaction force apparatus (DIFA) was designed to investigate the bubble-particle detachment process. The DIFA could directly measure the detachment force and visually observe the interfacial behavior during a particle detaching from an air bubble. The detachment process was composed of three sub-processes: bubble stretching process, bubble sliding process, and bubble necking process. Calculated detachment force showed good agreement with measurement force. The critical detachment force, defined as the maximum detachment force during detachment process, was proposed to determine whether a particle completely detached from a bubble. The Bond number was modified using the critical detachment force. The modified Bond number, which considers the bubble-particle detachment process, was more appropriate to evaluate the bubble-particle aggregate stability. It was found that the bubble-particle aggregate stability was enhanced by increasing surface hydrophobicity, whereas the stability was weakened by increasing particle size. The weak stability of bubble-particle aggregate results in a low recovery in coarse particle flotation.

中文翻译：

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使用动态相互作用力装置直接测量粒子和气泡之间的临界分离力

摘要 气泡-颗粒脱离是限制浮选粗颗粒回收的主要因素。设计了动态相互作用力装置 (DIFA) 来研究气泡-颗粒脱离过程。DIFA 可以直接测量脱离力，并在粒子从气泡中脱离过程中直观地观察界面行为。分离过程由三个子过程组成：气泡拉伸过程、气泡滑动过程和气泡颈缩过程。计算的脱离力与测量力显示出良好的一致性。临界分离力定义为分离过程中的最大分离力，用于确定颗粒是否完全与气泡分离。使用临界分离力修改邦德数。修改后的债券号，考虑了气泡-颗粒分离过程，更适合评估气泡-颗粒聚集体的稳定性。结果表明，气泡-颗粒聚集体的稳定性通过增加表面疏水性而增强，而稳定性通过增加粒径而减弱。气泡-颗粒集料的弱稳定性导致粗颗粒浮选回收率低。