Power demand and mixing performance of coaxial mixers in a stirred tank with CMC solution

doi:10.1016/j.cjche.2015.01.002

Abstract

Abstract: Experimental investigationwas carried out in an elliptical based stirred tank with a diameter of 0.48m to explore the power demand and mixing performance of coaxial mixers. Syrup and CMC solution (sodium carboxy methyl cellulose) were used as the Newtonian and non-Newtonian fluids, respectively. Four different coaxial mixers were combined with either CBY or Pfaudler impeller as the inner one, and anchor or helical ribbon (HR) as the outer one. Results show that Pfaudler-HR is the optimized combination among four coaxial mixers in this work, which provides the shortest mixing time given the same power consumption. Compared with the syrup solution, the increase of power input can make the mixing time decreasing more obviously in the CMC solution. The quantitative correlations for both syrup and CMC solutions were established to calculate the power draw and the mixing time of four coaxial mixers.

Key words: Non-Newtonian, fluids Coaxial mixer, Power demand, Mixing performance

摘要： Experimental investigationwas carried out in an elliptical based stirred tank with a diameter of 0.48m to explore the power demand and mixing performance of coaxial mixers. Syrup and CMC solution (sodium carboxy methyl cellulose) were used as the Newtonian and non-Newtonian fluids, respectively. Four different coaxial mixers were combined with either CBY or Pfaudler impeller as the inner one, and anchor or helical ribbon (HR) as the outer one. Results show that Pfaudler-HR is the optimized combination among four coaxial mixers in this work, which provides the shortest mixing time given the same power consumption. Compared with the syrup solution, the increase of power input can make the mixing time decreasing more obviously in the CMC solution. The quantitative correlations for both syrup and CMC solutions were established to calculate the power draw and the mixing time of four coaxial mixers.

关键词: Non-Newtonian, fluids Coaxial mixer, Power demand, Mixing performance

Yuyun Bao, Yu Lu, Qianqin Liang, Li Li, Zhengming Gao, Xiongbin Huang, Song Qin. Power demand and mixing performance of coaxial mixers in a stirred tank with CMC solution[J]. Chin.J.Chem.Eng., 2015, 23(4): 623-632.

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