微气泡形成机理及影响因素

Formation mechanism and influencing factors of micro-bubbles

尺寸不大于1 mm的微气泡具有在液体中上升速度较慢、比表面积较大和传质效率较高等特点,在精细化工和环保行业已有较好的应用业绩。石油化工加氢领域因其高温高压、有杂质、易结焦等特点,相比于其他类型微气泡的产生方法,锐孔分散型微气泡产气具有较高的适应性。文中通过分析气体在均匀锐孔处连续向液体中溢出气泡的过程,应用力学平衡关系综合考虑气泡受力的情况,得到影响气泡直径关键因素及其权重,并开发出适合加氢行业应用的微气泡发生器。研究发现在各种结构参数和工况参数中,锐孔直径和膜面湿润性对于微气泡的形成影响较大,锐孔均匀性影响气泡流中气泡均匀性。

Microbubbles with a size of no more than 1 mm have the characteristics of slow rising speed in liquid,large specific surface area and high mass transfer efficiency,and have been well applied in fine chemicals and environmental protection industries.In the field of petrochemical hydrogenation,due to its characteristics of high temperature,high pressure,impurities,easy coking and so on,compared with other types of microbubble generation methods,sharp hole dispersed microbubble gas production has higher adaptability.In this paper,by analyzing the process of gas continuously overflowing bubbles into the liquid at the uniform sharp hole,applying the mechanical equilibrium relationship to comprehensively consider the force on the bubbles,the key factors affecting the bubble diameter and their weights were obtained,and a microbubble generator suitable for the hydrogenation industry was developed.It is found that among various structural parameters and working conditions,the diameter of sharp hole and the wettability of film surface have a great influence on the formation of microbubbles,and the uniformity of sharp hole affects the uniformity of bubbles in bubble flow.