TY - JOUR
T1 - Particle formation from solution and slurry sprays
AU - Messing, Gary Lynn
AU - Gu, H. C.
AU - Mandanas, M.
PY - 1997/1/1
Y1 - 1997/1/1
N2 - The initial morphology of particles formed by spray drying or spray pyrolsis of solutions, sols or slurries, is determined by the relative velocity between the atomized droplet and the ambient gas in the furnace. A1 high relative velocities, the droplet can be disintegrated or flattened, whereas at low relative velocities the droplet remains spherical throughout the drying process. The time for respheroidization depends on the liquid properties and the solid content of the drying droplet. When the droplet reaches the percolation limit, the higher viscosity inhibits respheroidization, and the morphology of the deformed droplet is fixed. A new model based on the Weber number, percolation criteria, and the drying kinetics, is presented to predict particle morphology for various drying conditions. In addition, the effects of segregation during drying will be discussed in regard to its effect on particle formation during spray formulation. We will show how physical and chemical segregation processes occur in drying droplets, and how these segregation processes can be controlled to yield particles of designed morphology and internal phase distribution.
AB - The initial morphology of particles formed by spray drying or spray pyrolsis of solutions, sols or slurries, is determined by the relative velocity between the atomized droplet and the ambient gas in the furnace. A1 high relative velocities, the droplet can be disintegrated or flattened, whereas at low relative velocities the droplet remains spherical throughout the drying process. The time for respheroidization depends on the liquid properties and the solid content of the drying droplet. When the droplet reaches the percolation limit, the higher viscosity inhibits respheroidization, and the morphology of the deformed droplet is fixed. A new model based on the Weber number, percolation criteria, and the drying kinetics, is presented to predict particle morphology for various drying conditions. In addition, the effects of segregation during drying will be discussed in regard to its effect on particle formation during spray formulation. We will show how physical and chemical segregation processes occur in drying droplets, and how these segregation processes can be controlled to yield particles of designed morphology and internal phase distribution.
UR - http://www.scopus.com/inward/record.url?scp=17144434314&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=17144434314&partnerID=8YFLogxK
U2 - 10.1080/02726359708906764
DO - 10.1080/02726359708906764
M3 - Article
AN - SCOPUS:17144434314
SN - 0272-6351
VL - 15
JO - Particulate Science and Technology
JF - Particulate Science and Technology
IS - 2
ER -