OBJECTIVETo study the correlation of dry granulation with Chinese extract powder physical properties and dry granulating process parameters to find out the main factors affecting the granulation progress.

METHODThe correlation with the physical properties including angle of repose, compression degree, cohesion, water content, feeding speed, wheel speed and wheel pressure with the yield of grain was investigated by multiple regression analysis.

RESULTThe results showed that compression degree, water content, feeding speed and wheel pressure was positively correlated with the yield of grain in measured range. The angle of repose, cohesion, wheel speed was negative correlated with the yield of grain in measured range.

CONCLUSIONDry granulating was highly influenced by the physical properties of herbal extracts and the parameters of dry granulating process. The greater impact on grain dry method are compression, cohesion and wheel speed.