摘要
针对单乙醇胺水溶液吸收二氧化碳过程,采用粒子成像测速仪(PIV)对气泡周围的流场进行了测定,流场围绕气泡的对称轴呈对称分布。对速度场实验数据进行拟合,得到了泡顶对称轴上径向速度的分布方程。另外,采用实时激光全息干涉系统对不同液体流速下单乙醇胺吸收二氧化碳的传质过程进行了研究,通过CCD摄像机采集并记录下不同时刻的全息干涉条纹图。由干涉条纹图和浓度-折射率标准曲线,计算出传质达到稳态时气泡周围液相侧近界面浓度分布,近界面浓度及浓度边界层厚度。浓度分布呈指数衰减趋势,且浓度边界层厚度远远小于速度边界层厚度;随着液体流速的增加,气泡周围液相侧浓度边界层厚度和近界面浓度均减小。结合速度分布方程和对流扩散方程,推导出单乙醇胺水溶液吸收二氧化碳过程液相侧浓度分布模型。
The process of absorption of CO2 by monoethanolamine aqueous solution was studied under various liquid velocities. The flow field around bubble was measured by using particle image velocimetry （PIV）, it shows that the velocity field distributes symmetrically around the symmetrical axis of the bubble. Then the experimental data of the measured velocity field were fitted, and the equation of radial velocity distribution on the symmetrical axis of the frontal part of the bubble was obtained. In addition, the mass transfer process was studied by holographic interferometry, and the interferential fringes were photographed by a CCD and retained in the computer. According to the interferential fringes and standard curve of concentration-refractive index, the concentration field, the concentration near the interface and the concentration boundary layer thickness on liquid side were determined when mass transfer reaches stable. The experimental results show that the concentration distribution presents exponential decay, the boundary layer thickness of concentration is thinner than that of velocity; the concentration boundary layer thickness and the concentration near the interface decrease with the increase of liquid velocity. Based on the velocity distribution equation and the convection-diffusion equation, a model of concentration distribution on liquid side was developed for the process of CO2 absorption by monoethanolamine aqueous solution.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2009年第3期532-536,共5页
Journal of Chemical Engineering of Chinese Universities
基金
国家自然科学基金资助项目(20476073)
关键词
速度场
PIV
浓度场
激光全息干涉
气泡
velocity field
PIV
concentration field
holographic interferometry
bubble
