Secondary Nucleation Rate by Growing Crystals and Oscillation Phenomena in Sodium Borate Decahydrate Crystal Suspension

Crystal growth experiments were performed in a suspension system of sodium borate decahydrate crystals, to observe the surface status of crystals in the process of their growth, and to obtain the correlative equation of the factors (degree of supercooling, linear velocity in the crystallizer and revolution rate of the agitator) affecting secondary nucleation rate. It is also made clear that the average secondary nucleation rate based on the operation time is affected by the surface status of the growing crystals, and its rate osccillates against the operation time. This oscillation phenomena are discussed, based on the qualitative model of two series processes consisted of a diffuison stage and a surface reaction stage.