Particle shear and impact (PSI) tester: Evaluation of device performance

The Particle Shear and Impact tester has been developed to assess particle attrition in response to typical mechanical stresses prevailing in manufacturing plants. The particles are subjected to shear stresses by two counter-rotating rollers with an adjustable gap, and to repeated impacts through collisions at bends as they are recirculated in the tester. In this study, evaluation of the device performance and settings is described for attrition of enzyme granules. The extent of attrition of three different granule samples, subjected to impact alone, shear alone and coupled shear and impact tests is assessed and the sources of variability of the tester are investigated to determine its experimental repeatability. The mass collected in various parts of the tester is assessed both gravimetrically and by enzyme assay in order to investigate the device performance. Due to high sensitivity in enzyme dust analysis, adhesion of enzyme dust to surfaces influences the attrition variability. Three cleaning approaches are examined for removing enzyme dust deposited in the tester. (c) 2024 The Society of Powder Technology Japan. Published by Elsevier B.V. and The Society of Powder Technology Japan. This is an open access article under the CC BY license (http://creativecommons.org/ licenses/by/4.0/).