セッコウ粉体の流動性に対する粒子形状および各種リン酸カルシウム添加の影響

摘要

In order to improve flowability of gypsum powder in powder transport process, the influence of the particle size of gypsum and adding of various calcium phosphates on the flowability was investigated. The flowability estimated by using Kawakita equation increased with the average powder size increase of gypsum; the increase was especially drastic with the average powder diameter of 80-100μm. The adding of ground octacalcium phosphate (OCP) and hydroxyapa-tite were effective for the improvement as well as the well-known additive, calcium stearate, whereas α-tricalcium phosphate, β-tricalcium phosphate and as-prepared OCP were not effective.%粉体を取り扱う各種製造プラントでは，粉粒体の単位操作の中で輸送・供給と貯蔵が粉体プロセスの重要な部分を占めている.このような粉粒体の移動操作で起こるトラブルの中に閉塞（架橋）現象がある.閉塞現象は，ホッパの排出口において粉体間で架橋（ブリッジ）を形成し，重力による自由流出を妨げる現象である.