摘要
为了研究煤泥浮选过程中颗粒-气泡分离及稳定性机制,采用自主设计的浮选颗粒气泡粘附/脱附行为测试系统,考察了3种不同形状(长条形、三角锥形、球形)的长焰煤颗粒在气泡表面的脱附行为,通过临界脱附振幅评价颗粒-气泡的稳定性,并从力平衡的角度对试验现象进行解释。结果表明:球形颗粒比形状不规则的长条形和三角锥形颗粒更易从气泡上脱附,脱附行为与粘附模式密切相关。当颗粒长边与气泡接触时,三相润湿周边长,所受的毛细力大,颗粒-气泡稳定,因此需要更大的临界脱附振幅。当颗粒短边与气泡接触时,三相润湿周边短,所受的毛细力小,颗粒-气泡不稳定,临界脱附振幅小。该结论为煤泥浮选过程中减少颗粒-气泡脱附概率提供了理论依据。
In order to study the mechanism of particle-bubble separation and stability in coal slime flotation,a self-designed flotation particle bubble adhesion and detachment behavior test system was used to investigate the detachment behavior between long flame coal with three different shapes(long strip,triangular cone,sphere)and the surface of bubble.The stability of the particle-bubble was evaluated by the critical detachment amplitude,and the experimental phenomena were explained from the perspective of force balance.The results show that the spherical particles are more easily detached from the bubbles than the irregularly shaped elongated and triangular pyramidal particles.The detachment behavior is closely related to adhesion patterns.When the long side of the particle is in contact with the bubble,the three-phase contact line is long,the capillary force is large,and bubble-particle is stable,so a larger critical detachment amplitude is required.When the short side of the particle is in contact with the bubble,the three-phase contact line is short,the capillary force is small,bubble-particle is unstable,and the critical detachment amplitude is small.This conclusion provides theoretical basis for reducing particle-bubble detachment probability in coal slime flotation.
作者
郭芳余
张友飞
罗佳倩
邢耀文
桂夏辉
GUO Fangyu;ZHANG Youfei;LUO Jiaqian;XING Yaowen;GUI Xiahui(National Engineering Research Center of Coal Preparation and Purification,China University of Mining and Technology,Xuzhou 221116,China;School of Chemical Engineering and Technology,China University of Mining and Technology,Xuzhou 221116,China)
出处
《煤炭科学技术》
CAS
CSCD
北大核心
2020年第11期217-222,共6页
Coal Science and Technology
基金
国家重点研发计划资助项目(2018YFC0604702)
国家自然科学基金资助项目(51774286,51574236)。
关键词
颗粒形状
长焰煤
颗粒-气泡稳定性
煤泥浮选
particle shape
long flame coal
bubble-particle stability
coal slime flotation
