Continuous Melt Suspension Crystallization of Phosphoric Acid

Aimei Chen, Jiawen Zhu, Bin Wu, Kui Chen, Lijun Ji

Chemical Engineering Research Center, East China University of Science and Technology, Shanghai, PR China.

DOI: 10.4236/jcpt.2012.23014                

Abstract

A continuous melt suspension crystallization process has been presented for the purification of the phosphoric acid in this study, which is performed in the cascade of a mixed suspension mixed product removal (MSMPR) crystallizer and a gravity wash column for the subsequent solid-liquid separation. Dynamic behavior in the crystallizer and role of reflux ration on the purification efficiency of column are studied in detail. A reasonable steady state with respect to the liquid phase is achieved after 2 to 3 hrs, which is followed by a solid-phase steady state in terms of the slurry density after 4 hrs. Reflux ratio is the effective parameter for separation and purification by the crystallization equipment from the influences of reflux ratio on the purity of product, the number of theoretical plates and the stability of the operations.

Keywords

Phosphoric Acid; Suspension Crystallization; Msmpr Crystallizer; Reflux Ratio

Conflicts of Interest

The authors declare no conflicts of interest.

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