双层桨搅拌槽内局部气液分散特性研究  

Study on local gas-liquid dispersion in dual-impeller aerated stirred vessel

作　　者：李良超[1] 王嘉骏[1] 顾雪萍[1] 冯连芳[1] 李伯耿[1] 

机构地区：[1]浙江大学化学工程与生物工程学系,化学工程国家重点实验室,浙江杭州310027

出　　处：《浙江大学学报（工学版）》2009年第3期463-467,共5页Journal of Zhejiang University：Engineering Science

基　　金：国家重点基础研究专向经费资助项目(2006CB623804)

摘　　要：采用电导电极探针法对双层组合桨搅拌槽内局部气含率分布规律进行了研究.结果表明,在槽底区和叶轮区,局部气含率沿径向分别增加和减小;而在其他区域,局部气含率沿径向先增加后减小.随着通气量的增加,槽内大部分区域的局部气含率增加,槽底区的局部气含率减小;随着搅拌转速的增加,上循环区局部气含率基本不变,其他区域的局部气含率增加.采用标准方差法对局部气含率分布的均匀性进行了分析.随着通气量的增加,搅拌槽内局部气含率分布均匀性减小,但减小的趋势变缓,并最终趋于不变.随着搅拌转速的增加,局部气含率分布均匀性增加,达到一定搅拌转速后趋于不变.实验回归了大通气量下平均气含率随通气量和单位体积液体功率消耗的关联式.The local gas holdup in a dual-impeller agitated gas-liquid vessel was measured with a conductivity probe. The experiment results showed that the local gas holdup increased with the increase of the radial distance in the bottom region, and decreased in the impeller region, while it increased firstly and then decreased in other regions. With the increase of the superficial gas velocity, the local gas holdup decreased in the bottom region while it increased in other regions in the vessel. The local gas holdup in the upper circulation region was almost not affected by the agitated speed while it increased in other regions with the increase of the stirring speed. The standard deviation of the local gas holdup was used to analyze the uniformity of the local gas holdup distribution in the vessel. The smaller the standard deviation was, the better the gas dispersion was. The standard deviation of the local gas holdup increased with the increase of the superficial gas velocity while it decreased with the increase of the stirring speed. The standard deviation of the local gas holdup kept almost unchanged under the high superficial velocity or at the high stirring speed. The global gas holdup correlation between the power consumption and superficial gas velocity was proposed.

关 键 词：气液搅拌槽 气含率 双层组合桨 

分 类 号：TQ027.3[化学工程]