RELATIONSHIPS BETWEEN PARTICLE PROPERTIES AND BULK BEHAVIOR FOR SOME INDUSTRIAL POWDERS

A series of industrial powders, most of them organic, were characteriz ed in terms of volumetric mean size, size distribution, density, parti cle shape, water rentention characteristics (under a series of control led ambient relative humidities) and loosely packed and densely packed voidages (giving the compressibility). The behaviour of the powders i n powder handling apparatus (a precision powder filler) was also deter mined. The minimum and maximum bulk densities of the powders were rela ted to the properties of the individual particles by means of a semi-e mpirical equation. The filling capacity of the powder handling apparat us was found to be related to the maximum bulk density of the powder w hile the filling accuracy turned out to be related to the compressibil ity of the powder. Knowing these interrelations made it possible to pr edict the powder behaviour in the handling apparatus directly on basis of the particle properties.