摘要
介绍了涡旋脉冲式反应装置的基本结构和特点,并选择Ca(OH)2-H2O-CO2这一多相反应体系,利用涡旋脉冲式反应装置制备纳米碳酸钙。实验研究了气液比h、喷口速度up、Ca(OH)2悬浮液初始浓度Ci、混合气体中CO2气体含量j、脉冲发生器的频率f等操作条件对碳化反应时间Rt的影响。实验结果表明,随h、pu、j增大,Rt明显减小;Ci增加导致Rt增大;在5Hzf<的范围内,随f增大,与液滴在涡旋室内的飞行时间相比,液滴表面更新速率增大占优势,导致Rt减小,在5Hzf>的范围内,随f增大,相撞的瞬间液滴的相对速度及在涡旋室内的飞行时间降低,导致Rt逐渐增大。
The basic structure and characteristics of a new process intensification equipment named Vortex and Pulsed Reaction Equipment (VPRE) were introduced, and the nano-CaCO3 was prepared in VPRE by adopting a multiphase reaction system of Ca(OH)2-H2O-CO2. Effects of operating parameters, such as the ratio of the gas to liquid flowrate η, liquid jet speed uP, the initial content of Ca(OH)2 Ci, the percentage of CO2 in gas mixture ψ and frequency of the pulse generator f on carbonation time tR were investigated. Experimental results indicate that tR decreases remarkably with the increase of η, up, ψ and the decrease of Ci. Compared with the decrease of movement time of the droplets in VPRE, the increase of renewing rate of droplets surface is dominant in the range of f > 5 Hz. This results in decrease of tR with an increasing f. Whereas tR increases gradually with an increasing f in the range of f > 5 Hz due to the decrease of movement time of the droplets in vortex chamber and the decreased relative velocity among colliding droplets.
出处
《高校化学工程学报》
EI
CAS
CSCD
北大核心
2004年第5期590-594,共5页
Journal of Chemical Engineering of Chinese Universities
关键词
涡旋脉冲式反应装置
过程强化
纳米碳酸钙
碳化过程
Calcium compounds
Carbon dioxide
Multiphase flow
Nanostructured materials
Pulse generators
