Experimental investigation of the mixing efficiency via intensity of segregation along axial direction of a rotating bar reactor

doi:10.1016/j.cjche.2023.01.003

Chinese Journal of Chemical Engineering ›› 2023, Vol. 59 ›› Issue (7): 153-159.DOI: 10.1016/j.cjche.2023.01.003

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Experimental investigation of the mixing efficiency via intensity of segregation along axial direction of a rotating bar reactor

Abdelgadir Bashir Banaga^1,2, Yan-Bin Li^1,2,3, Zhi-Hao Li^1,2, Bao-Chang Sun^1,2, Guang-Wen Chu^1,2

1. State Key Laboratory of Organic-Inorganic Composite, Beijing University of Chemical Technology, Beijing 100029, China;
2. Research Center of the Ministry of Education for High Gravity Engineering and Technology, Beijing University of Chemical Technology, Beijing 100029, China;
3. Department of Chemical Engineering, Tiangong University, Tianjin 300387, China

Received:2022-10-03 Revised:2023-01-07 Online:2023-10-14 Published:2023-07-28
Contact: Bao-Chang Sun,E-mail:sunbc@mail.buct.edu.cn;Guang-Wen Chu,E-mail:chugw@mail.buct.edu.cn
Supported by:
This work was supported by the National Natural Science Foundation of China (21725601).

Experimental investigation of the mixing efficiency via intensity of segregation along axial direction of a rotating bar reactor

Abdelgadir Bashir Banaga^1,2, Yan-Bin Li^1,2,3, Zhi-Hao Li^1,2, Bao-Chang Sun^1,2, Guang-Wen Chu^1,2

1. State Key Laboratory of Organic-Inorganic Composite, Beijing University of Chemical Technology, Beijing 100029, China;
2. Research Center of the Ministry of Education for High Gravity Engineering and Technology, Beijing University of Chemical Technology, Beijing 100029, China;
3. Department of Chemical Engineering, Tiangong University, Tianjin 300387, China

通讯作者: Bao-Chang Sun,E-mail:sunbc@mail.buct.edu.cn;Guang-Wen Chu,E-mail:chugw@mail.buct.edu.cn
基金资助:
This work was supported by the National Natural Science Foundation of China (21725601).

Abstract

Abstract: As a significant index to evaluate the mixing efficiency, studying the concentration distribution is directly related to the intensity of segregation (I_s). In this work, the I_s of the mixture composed of NaCl solution-water was investigated experimentally in a rotating bar reactor (RBR) by the conductivity method. The results showed that the mixing efficiency was improved along the axial direction from the bottom to the top in the RBR. The concentration distribution at the bottom section was more uneven, and I_s was higher compared with the top section, which decreased from 6.53×10^-5 to 1.57×10^-7. With the increase of rotational speed from 0 to 700 r·min^-1, I_s at the bottom and top sections decreased from 4.27×10^-3 to 7.10×10^-5 and from 1.93×10^-3 to 7.29×10^-7, respectively. The increases flow rate of solution A, and the decreases of concentration of NaCl and flow rate of solution B gave rise to the reduction of I_s, signifying an improved mixing efficiency. The results revealed that the conductivity method used in this paper has high efficiency and low cost to measure the, which indicates a promising prospect for estimating reactors’ mixing performance.

Key words: Intensity of segregation, Mixing efficiency, Rotating bar reactor, Conductivity method, Concentration distribution

摘要： As a significant index to evaluate the mixing efficiency, studying the concentration distribution is directly related to the intensity of segregation (I_s). In this work, the I_s of the mixture composed of NaCl solution-water was investigated experimentally in a rotating bar reactor (RBR) by the conductivity method. The results showed that the mixing efficiency was improved along the axial direction from the bottom to the top in the RBR. The concentration distribution at the bottom section was more uneven, and I_s was higher compared with the top section, which decreased from 6.53×10^-5 to 1.57×10^-7. With the increase of rotational speed from 0 to 700 r·min^-1, I_s at the bottom and top sections decreased from 4.27×10^-3 to 7.10×10^-5 and from 1.93×10^-3 to 7.29×10^-7, respectively. The increases flow rate of solution A, and the decreases of concentration of NaCl and flow rate of solution B gave rise to the reduction of I_s, signifying an improved mixing efficiency. The results revealed that the conductivity method used in this paper has high efficiency and low cost to measure the, which indicates a promising prospect for estimating reactors’ mixing performance.

关键词: Intensity of segregation, Mixing efficiency, Rotating bar reactor, Conductivity method, Concentration distribution

Abdelgadir Bashir Banaga, Yan-Bin Li, Zhi-Hao Li, Bao-Chang Sun, Guang-Wen Chu. Experimental investigation of the mixing efficiency via intensity of segregation along axial direction of a rotating bar reactor[J]. Chinese Journal of Chemical Engineering, 2023, 59(7): 153-159.

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Experimental investigation of the mixing efficiency via intensity of segregation along axial direction of a rotating bar reactor

Experimental investigation of the mixing efficiency via intensity of segregation along axial direction of a rotating bar reactor

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