Coupling of Contact Nucleation Kinetics with Breakage Model for Crystallization of Sodium Chloride Crystal in Fluidized Bed Crystallizer

Abstract

There are many nucleation theory-based different mechanisms. These theories mainly focused on production parameters in the crystallization and less on physical properties of crystals. In this research, a new model of contact nucleation theory coupled with the breakage mechanism of crystals is applied to describe the collision process in sodium chloride crystallization. This coupling nucleation model is presented here which relates the number of contact-collision site in nucleation owing to collision rate and the interfacial energy. F2 in the expression of the classic contact nucleation rate is redefined as a power function with the physical properties of crystals and breakage propensity. The experiment results indicate that crystal breakage propensity has a significant influence on the nucleation rate. Finally, analysis of the contact nucleation kinetic model and comparison with experiments reveal that the new nucleation model results are in better agreement with experiments. This new nucleation model is confirmed to represent the time-dependent collision behavior. The parameters of model are strongly related to the physical properties of crystal and fluidization conditions.

Nucleation and Growth Kinetics of Sodium Chloride Crystallization from Water and Deuterium Oxide

“…The available previous measurements of the width of the metastable zone of NaCl in H 2 O are in general agreement with the largest values measured here. This is consistent with the fact that previously published measurements were gathered from a fluidized bed crystallizer at relatively low shear conditions; the width of the metastable zone is observed to decrease with increasing shear stress [43,57]. The growth rates we have measured, while consistent with the previous literature at intermediate supersaturation, are significantly higher than previous measurements at lower supersaturation.…”

“…[52] (see the note above about the methodology behind this source). Other sources also report the secondary nucleation rate but typically have used very different conditions, such as evaporative crystallization [56] or a fluidized bed [57], so for clarity, we do not compare these directly to the data here. Under overhead stirring conditions, rates from seeded samples are typically larger by at most a small factor (2 to 5), but given the variation in repeat experiments, such differences should not be overinterpreted.…”

The Reaction Extraction Combining Crystallization for Growth of Sodium Chloride in a Spray Fluidized Bed Crystallizer

“…e C.V. is a statistical measure of the dispersion of data points in a data series around the crystal mean particle size [20]. e coefficient of variation represents the ratio of the standard deviation to the mean particle size, and it is a useful statistic for comparing the degree of variation from one data series to another, which reflects the uniformity of crystals [21]. e larger the values of C.V., the wider the CSD.…”