Tuyển tập các báo cáo nghiên cứu khoa học trên tạp chí khoa học vật lý quốc tế đề tài: Mixing Behavior of Binary Polymer Particles in Bubbling Fluidized Bed | Journal of Physical Science Vol. 19 1 13-29 2008 13 Mixing Behavior of Binary Polymer Particles in Bubbling Fluidized Bed . Tasirin . Kamarudin and . Hweage Department of Chemical and Process Engineering Universiti Kebangsaan Malaysia 43600 UKM Bangi Selangor Malaysia Corresponding author ctie@ Abstract Fluidized bed mixer offers the most efficient and economical process compared to other mixers. However less effort has been devoted to understand the local behavior of the solids in fluidized bed partly due to the lack of reliable experimental methods. Thus the objective of this paper was to view the local mixing behavior and property of a free flow polymer binary mixture in bubbling fluidized bed. In this work an experimental study of mixing process of free flowing polymers binary mixtures at different densities and colors in bubbling fluidized were investigated. The mixing properties were studied by analyzing the variation of the proportions of the marked particles with time and position in the bed. The variation of mixture composition based on the samples incorporated into Lacey mixing index that describes the degree of mixing of the particle at particular time. This method enables the assessment of the overall mixing behavior in terms of the rate of mixing through estimation of the time required for the mixing index to increase from zero to a certain value and with the degree of mixing at the mixing equilibrium stage. Finally the parameters were optimized. Results showed that gas velocity and bed depth were important parameters influencing the solids mixing in the bubbling fluidized bed. From the results complete mixing of binary polymer particles was attained at a bed depth of 17 cm and gas velocity of Umf in the fluidized bed. Keywords polymer particles mixing fluidized bed 1. INTRODUCTION Fluidized bed mixer offers the natural mobility afforded particles in the fluidized bed. The mixing is largely convective with the circulation
