Micromixing of a Two Phase System in a Stirred Tank with Multiple Impellers

Lei Yang, Jingcai Cheng, Ping Fan, Chao Yang

Key Laboratory of Green Process and Engineering, Institute of Process Engineering Chinese Academy of Sciences, Beijing 100190, China.

DOI: 10.4236/ampc.2012.24B039                

Abstract

The competitive iodide/iodate reaction scheme was used to ascertain the micromixing in the stirred solid-liquid systems. Two different glass beads from 450 to 1250 μm were tested. The effect of solid particles on reaction selectivity with multiple impellers at different feed points has been investigated. It was confirmed that glass beads as a second phase were suitable for the study. The segregation index has changed significantly only for the medium-sized particles at relatively high solid holdups. The cloud formation was clearly observed for the medium-sized particles at a concentration of 12.12 wt. %. When feeding into the clear liquid above the cloud, the value of the segregation index increased significantly. However, in the presence of particles of 1-1.25 mm, the influence on the selectivity was negligible when the agitation speed was increased.

 

 

 

Keywords

Micromixing; Parallel Reactions; Two Phases; Multiple Impellers

Conflicts of Interest

The authors declare no conflicts of interest.

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