Droplet characteristics in the multi-staged high speed disperser with single inlet

doi:10.1016/j.cjche.2018.12.017

Abstract

Abstract: Droplet characteristics in the cavity zone of a multi-staged high speed disperser with single inlet were studied in this paper. The influences of both the operating and structural parameters on the mean droplet diameter, size distribution and liquid flux distribution were quantitatively analyzed. The result showed that the mean droplet diameter decreased with the increase of rotational speed and the number of rotors; whilst there is little influence on the inlet flow rate. In the experimental range, the minimum value of mean droplet diameter is 0.57 mm, 0.48 mm, 0.41 mm in the two-staged, three-staged and four-staged rotors, respectively. The Rosin-Rammler (R-R) distribution could describe the droplet size distribution appropriately, and it became uniform with the increase of rotational speed and the number of rotor, while the inlet flow rate had little effect on the droplet size distribution. The liquid flux distribution curves were always unimodal. With the increase of rotational speed, the location of maximum liquid flux ratio moved from zone 3 to zone 4 and this value decreased from 22.1% to 18.1%. Using Coefficient of Variation (CV) to indicate the uniformity of liquid flux distribution, it was found that the CV decreases from 47.5% to 22.7% when the number of rotor increased from 2 to 4.

Key words: Droplet, High speed disperser, Size distribution, Liquid flux distribution

摘要： Droplet characteristics in the cavity zone of a multi-staged high speed disperser with single inlet were studied in this paper. The influences of both the operating and structural parameters on the mean droplet diameter, size distribution and liquid flux distribution were quantitatively analyzed. The result showed that the mean droplet diameter decreased with the increase of rotational speed and the number of rotors; whilst there is little influence on the inlet flow rate. In the experimental range, the minimum value of mean droplet diameter is 0.57 mm, 0.48 mm, 0.41 mm in the two-staged, three-staged and four-staged rotors, respectively. The Rosin-Rammler (R-R) distribution could describe the droplet size distribution appropriately, and it became uniform with the increase of rotational speed and the number of rotor, while the inlet flow rate had little effect on the droplet size distribution. The liquid flux distribution curves were always unimodal. With the increase of rotational speed, the location of maximum liquid flux ratio moved from zone 3 to zone 4 and this value decreased from 22.1% to 18.1%. Using Coefficient of Variation (CV) to indicate the uniformity of liquid flux distribution, it was found that the CV decreases from 47.5% to 22.7% when the number of rotor increased from 2 to 4.

关键词: Droplet, High speed disperser, Size distribution, Liquid flux distribution

Ao Nie, Ziqi Cai, Zhengming Gao, Zhimiao Wang, Archie Eaglesham. Droplet characteristics in the multi-staged high speed disperser with single inlet[J]. Chinese Journal of Chemical Engineering, 2019, 27(8): 1756-1764.

Ao Nie, Ziqi Cai, Zhengming Gao, Zhimiao Wang, Archie Eaglesham. Droplet characteristics in the multi-staged high speed disperser with single inlet[J]. 中国化学工程学报, 2019, 27(8): 1756-1764.

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