多级鼓泡塔中液相返混系数与交换速度的研究  

Liquid-phase backmixing coefficient and interchange velocity in multi-stage bubble column

作　　者：练以诚[1] 秦岭[1] 杨索和[1] 靳海波[1] 

机构地区：[1]北京石油化工学院化学工程系,北京102617

出　　处：《化学工程》2011年第7期43-46,共4页Chemical Engineering(China)

基　　金：国家自然科学基金资助项目(20776018);北京市自然科学基金资助项目(2093034);北京市属高等学校人才强教深度计划资助项目(PHR200906139)

摘　　要：采用示踪方法对高2 000 mm,内径282 mm多级筛板鼓泡塔内液相返混系数进行测量研究,并通过扩散-返混模型以及RTD曲线给出鼓泡塔内筛板上下二侧液体交换速度,同时考查了表观气速、开孔率等因素对轴向扩散系数与液体交换速度的影响。根据实验得出鼓泡塔内轴向返混系数以及液体交换速度与表观气速、开孔率有很大关系,均随表观气速以及开孔率的增大而增大。对于空塔中轴向扩散系数,实验计算值与文献中所提出的关系式相吻合。筛板的开孔大小也影响到液体交换速度,开孔孔径越大,气泡越容易通过,对液体的阻碍力也降低,使气液更容易交换,从而使筛板二侧的液体交换速率增加。另外,鼓泡塔内液体交换速度规律与文献中结论基本一致。The liquid-phase backmixing coefficient of the multi-stage bubble column（2 000 mm in height,282 mm in inside diameter） was measured with the tracer method,and the liquid interchange velocity between the two sides of sieve plate was obtained by using the dispersion-backmixing model and the residence time distribution（RTD） curve.The effect of superficial gas velocity and aperture ratio on the axial dispersion coefficient and the liquid interchange velocity was investigated.The results show that the superficial gas velocity and the aperture ratio have great influences on the axial dispersion coefficient and the liquid interchange velocity,both of which increase with the increase of the superficial gas velocity or aperture ratio.And in the bubble column without sieve plates,the measured value of axial dispersion coefficient is consistent with the literature relation.The opening size of the sieve plate also influences the liquid interchange velocity,that is,the bigger opening size can result in an easy passthrough of bubbles and reduce the resistance to liquid,thus making the gas-liquid interchange easily and increasing the liquid interchange rate at both sides of sieve plate.Besides,the law of liquid interchange velocity is in harmony with the literature conclusion.

关 键 词：多级鼓泡塔 扩散系数 液体交换速度 

分 类 号：TQ021[化学工程]