School of Materials Science and Engineering, Anhui University of Science and Technology

射流混合装置被广泛应用于各个领域，其参数对引射性能、微粒运动及作用机制会产生重要的影响。但目前应用于煤泥浮选领域的射流混合装置多变参数缺乏系统性优化。为了优化射流装置的多变参数，搭建射流混合测试系统，探究面积比Ar、喉嘴距Le、喉管长度L、引射管开启度γ和喷嘴出口速度V等关键参数对引射性能的影响规律；基于物理模型参数优化值，调节测试系统，研究射流流场对物料的作用机制，考察射流流场对煤粒表面细泥的剥离能力；运用高速摄像仪捕捉射流流束对引射气泡的卷吸破碎情况；采用激光粒度分析仪揭示气泡粒径的迁移规律。结果表明：当面积比Ar = 3.24、喉嘴距Le = 0.56 Dh（Dh为喉管直径）时，引射流体流量比q最大；综合考虑引射能力和沿程损失，当喉管长度L = 9Dz（Dz为喷嘴直径）、喷嘴出口速度V≥15 m/s时，射流装置的引射性能最为理想；引射流体的流量与引射管开启度γ成正比关系，引射速度受限于射流速度（以喷嘴出口速度V表征），当射流速度达到15 m/s，引射速度达到上限；基于最优引射性能参数，单次射流混合作用对物料解离及分散效果等同于激光粒度分析仪自带搅拌装置以500 r/min转速搅拌4～4.5 min；采用EDS能谱仪测试射流作用前后物料所含C、O、Al和Si等元素的变化，验证了射流作用对细泥罩盖的剥离能力；当射流速度达到7.2 m/s时，气泡会瞬间被粉碎成粒径更小的气泡群，90%以上气泡粒径小于45 μm。

The jet mixing device is widely used in various fields, and its parameters have an important influence on the ejection performance, particle movement and action mechanism. But the variable parameters of the jet mixing device used in the slime flotation field lack systematic optimization. In order to optimize the variable parameters of the jet mixing device, a jet mixing test system was set up to explore the influence of key parameters such as area ratio Ar, throat-nozzle distance Le, the length of throat tube L, opening degree of the ejection tube γ and nozzle outlet velocity V on the ejection performance. Based on the parameter optimization value of the physical model, the action mechanism of the jet flow field on the material was studied by adjusting the test system, and the stripping ability of fine mud on coal surface by jet flow field was investigated. A high-speed camera was used to capture the entrainment and breakage of the jet stream to the ejection bubble. The migration law of bubble size was revealed by laser particle size analyzer. The results show that: when the area ratio Ar = 3.24 and the throat-nozzle distance Le = 0.56Dh (Dh is the diameter of the throat tube), the ejection flow ratio q reached the maximum. Considering the ejection capacity and linear loss of the device, when the length of throat tube L = 9Dz (Dz is the diameter of the nozzle) and nozzle outlet velocity ≥15 m/s, the ejection performance is the ideal. The flow rate of the ejector fluid is proportional to the opening degree of the ejection tube. The ejection velocity is limited by the jet velocity (which is represented by the nozzle outlet velocity). When the jet velocity reaches 15m/s, the ejection velocity reaches the upper limit. Based on the optimal ejection performance parameters, the separation and dispersion effect of once jet mixing is equivalent to the mixing device of laser particle size analyzer at 500 r/min speed of 4~4.5 min. EDS was used to test the changes of C, O, Al and Si elements in materials before and after jet action, which verified the stripping ability of the fine mud cover by jet action. When the jet velocity reaches 7.2 m/s, the bubbles are instantly crushed into smaller bubbles, of which more than 90 % are smaller than 45 μm.

安徽省教育厅高校科学研究资助项目(KJ2021A0429)；安徽省教育厅高校优秀拔尖人才培育资助项目（gxyqZD2021109）；安徽省自然科学基金面上资助项目（2108085ME160）

周　伟，王淑杰，朱金波，等. 射流混合装置多变参数试验优化及分散机制[J]. 煤炭科学技术，2023，51（S1）：421−428.

ZHOU Wei，WANG Shujie，ZHU JinBo，et al. Variable parameter optimization and experimental study of jet mixing device[J]. Coal Science and Technology，2023，51（S1）：421−428.