A regime map for stages in high shear mixer agglomeration using ultra-high viscosity binders

摘要

The porosities and saturation levels of high shear mixer agglomerates,containing zeolite powder bound with a highly viscous surfactant paste [linear alkylbenzene sulphonate (LAS)],were determined as a function of mixing time by performing a series of simple liquid immersion experiments.The results validated,to a certain extent,the use of the secondary break point (P2) obtained from a logarithmic tapping analysis of the bulk material as a measure of the individual granule plastic yield during tapping.The bulk material tapping parameter P2 was also used to represent the dynamic yield stress (Yg) of the granules.This enabled the determination of the Stokes deformation number (Stdef = psU2/2Yg) for the granules,which was employed on an agglomeration regime map as described by Iveson et al.Powder Technol.117,83-97 (2001).It was found that the variation in granule morphology with time was reflected accurately by the parameter trajectory on the regime map.The results were in accord with the previously reported agglomeration mechanism for this system.