PARTICLE BREAKAGE IN THE CYCLONES OF FLUIDIZED BED SYSTEMS

A breakage model is developed to predict the change in particle size distribution of brittle materials that undergo mechanical stress in gas cyclones. The breakage probability depends on the cyclone inlet gas velocity, solids load, particle size, and a material-specific constant. The model is validated with data from experiments on a laboratory gas cyclone with aluminum oxide and iron oxide. The results are applied to calculate the particle size distribution of a chemical looping combustion process with iron ore as oxygen carrier

PREDICTION OF CATALYST ATTRITION IN AN INDUSTRIAL FLUIDIZED BED PLANT BASED ON LAB SCALE ATTRITION TESTS

The concept that catalyst attrition in a fluidized bed process can be simulated based on the attrition characteristics of the catalyst determined on labscale is applied to DuPont’s large scale process of maleic anhydride production from n-butane using a vanadium phosphorus oxide (VPO) catalyst. In the present cooperation effort the performance data and design parameters of the large scale plant are supplied by the École Polytechnique de Montréal and DuPont. At Hamburg University of Technology the catalyst’s attrition characteristics were determined in labscale attrition tests. Furthermore the fate of the solids in the process was simulated. The results of the simulation are compared with the performance data of the industrial process