JCPT  Vol.2 No.3 , July 2012
Continuous Reaction Crystallization of Struvite in a DTM Type Crystallizer With Jet Pump of Ascending Suspension Flow in a Mixing Chamber–Kinetic Approach of the Process
Abstract: Reaction crystallization of struvite in water solutions containing 0.20 mass % of phosphate(V) ions by magnesium and ammonium ions addition was investigated experimentally. Process was carried out in DTM type crystallizer with liquid jet pump device in 298 K assuming stoichiometric conditions. Struvite crystals of mean size Lm 5.2-23.0 μm were produced depending on pH (9-11) and mean residence time of suspension in a crystallizer τ (900-3600 s). Under these conditions linear growth rate of struvite crystals (SIG MSMPR kinetic model) decreased 2-time with the increase in pH and 3-time with the elongation of mean residence time of crystal suspension from 7.11×10-9 m/s (pH 9, τ900 s) to 1.65×10-9 m/s (pH 11, τ3600 s). Nucleation rate varied within the 7.9×108-1.8×1010 1/(sm3) limits. Struvite product of maximal linear size exceeded 100 μm with 10 vol. % of < 3 μm fraction corresponded to pH 9 and τ3600 s.
Cite this paper: A. Mazienczuk, A. Matynia, K. Piotrowski and B. Wierzbowska, "Continuous Reaction Crystallization of Struvite in a DTM Type Crystallizer With Jet Pump of Ascending Suspension Flow in a Mixing Chamber–Kinetic Approach of the Process," Journal of Crystallization Process and Technology, Vol. 2 No. 3, 2012, pp. 96-104. doi: 10.4236/jcpt.2012.23012.

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