Industrial & Engineering Chemistry Research, Vol.46, No.4, 1277-1285, 2007
Pilot plant investigation on the kinetics of dextrose cooling crystallization
This paper deals with an experimental study aimed at determining the kinetic expressions of both crystal growth and dextrose monohydrate nucleation from industrial aqueous solutions, containing polysaccharides as the main impurities. First, investigations at the bench scale were performed to evaluate the exponents of the kinetic power law expressions of both crystal growth and nucleation rates by specifically oriented experiments, and then, a pilot scale crystallizer was operated on an industrial site to determine the overall crystallization kinetics under industrial operating conditions. A simulation model was then implemented by using the gPROMS package both to interpret the experimental results and to obtain three kinetic coefficients of crystal growth and nucleation rates, adopted as adjusting parameters. The model allowed a satisfactory prediction of both the crystal size distributions (CSDs) and the dextrose concentration profiles. A weak correlation among the adjusting parameters was ascertained.