文献类型：期刊文献

英文题名：Power consumption, local and average volumetric mass transfer coefficient in multiple-impeller stirred bioreactors for xanthan gum solutions

作者：Xie, Ming-hui[1];Xia, Jian-ye[1];Zhou, Zhen[1];Zhou, Guo-zhong[2];Chu, Ju[1];Zhuang, Ying-ping[1];Zhang, Si-liang[1];Noorman, Henk[3]

机构：[1]E China Univ Sci & Technol, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China;[2]Wenzhou Great Wall Mixer Design Inst, Wenzhou 325019, Peoples R China;[3]DSM Biotechnol Ctr, NL-2600 MA Delft, Netherlands

年份：2014

卷号：106

起止页码：144

外文期刊名：CHEMICAL ENGINEERING SCIENCE

收录：;EI(收录号：20135117104978);WOS:【SCI-EXPANDED(收录号:WOS:000329458200015)】；

基金：This work was supported by the Major State Basic Research Development Program of China (973 Project) (Grant no. 2013CB733605), and Open Funding Project of the State Key Laboratory of Bioreactor Engineering is gratefully acknowledged.

语种：英文

外文关键词：Power; Mass transfer; Xanthan gum; Non-Newtonian fluid; Impeller combination

摘要：Mass transfer and mixing performances are very critical for xanthan gum fermentation process. Power consumption, local and average volumetric mass transfer coefficient (k(L)a) were compared for six impeller combinations in a 50 L perspex tank with xanthan gum solutions. Impellers used in various combinations can be distinguished as two categories: "small-diameter" impeller, which include Rushton turbine, hollow blade turbine and wide-blade hydrofoil impeller and "large-diameter" including ellipse gate impeller. Intermig and double helical ribbon. The results show that in order to gain the same power input, the rotating speed of "small-diameter" impeller combinations increases as the concentration of xanthan gum increases, while it decreases for "large-diameter" impeller combinations. The two categories also show distinguished mass transfer rates. For the "small-diameter" impeller combinations, the k(L)a values near the wall region drop faster than that in other areas as the concentration of xanthan gum increases. While for the "large-diameter" impeller combinations, the distribution of k(L)a is homogenous except in the bottom area but with poor gas dispersion capabilities as concentration of xanthan gum increases. The averaged k(L)a for each impller combination was correlated well with the specific gassed power input, superficial gas velocity and effective viscosity. The obtained correlation shows that the k(L)a strongly depends on specific power input and viscosity, but is less influenced by the gas flow rate. (C) 2013 Elsevier Ltd. All rights reserved.