A Novel Design of Heat Exchanger for Epsom Salt Cooling Crystallization

Abstract:

We introduced a design of a novel cooling heat exchanger for crystallization process of MgSO₄.7H₂O, and described the concepts of primary nucleation and secondary nucleation. To avoid the primary nucleation during crystallization process, the super-cooling degree limit of the salt lake brine was measured to define the supersaturation limit to MgSO₄.7H₂O, and the result is 1.32°C at-1°C. In this design, a primary circulation of solution is employed with a large enough flow rate to control the super-cooling degree of solution not to exceed 0.7 °C. A secondary circulation of cooling media is designed to add to this system, instead of the coldest cooling media being fed to shell directly, it is fed to the circulation pipe of the shell. It will help to prevent the supersaturation of solution exceeding the metastable zone width, thus to gurantee no primary nucleation during the Epsom salt crysatllization process.

• Periodical: Advanced Materials Research (Volumes 881-883)
• Pages: 1505-1508
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.881-883.1505
• Online since: January 2014
• Authors: Ai Qun Zhang*, Yan Fei Wang
• Keywords: Crystallization, Epsom Salt, Heat Exchanger

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