セラミックスの製造プロセスにおける圧縮成型操作rnでは，顆粒層を圧縮して得られる成形体の粒子構造がrn均質，かつ高密度であることが非常に大切である。こrnのためには，成形に用いる顆粒の粒子形状，表面特性rnや力学特性が重要で，高い流動性と庄密性を発現させrnるために，滑らかな球形の中実顆粒で，適度な強度とrn変形流動性を持つことが求められる。%The formation mechanism of granules in spray drying process was investigated by DEM-CIP method simulation coupled with a new binder segregation model. To confirm the validity of proposed binder segregation model, experiment on drying of aqueous slurry containing fine particles and binder was performed. The experimental concentration distribution of binder in a dried powder bed agreed well with the simulated one and this result shows that the proposed segregation model is valid to represent segregation phenomenon in the dried granule. Spherical hollow granules were formed with increasing the binder concentration, and the granules were dimpled at a higher concentration of binder. When the binder concentration in the surface region of a slurry droplet increased during drying, a shell of granule was formed because particle migration was inhibited by high fluid viscosity. For the rigid shell, granules were hollow. When the shell was formed early in drying and its thickness was thin, granule surface partially collapsed inward, whereas the granule resulted in sinking granules.
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