The main objective of this work was the study of the fluidization behaviour of a glass powderin order to allow its application by electrostatic pulverisation. The high density and the smalldiameter of the original product lead to bed channelling and slugging. To avoid theseinconsistency problems, different fluidization-aide techniques were experimented which wereincorporation of easy-to-fluidise large spherical glass particles to the glass powder, theaddition of four different types of flow conditioner (or glidants) and the use of mechanicalagitation. The quality of fluidization was determined by monitoring the pressure drop throughthe bed during fluidization experiments at decreasing air velocities.Two sizes of spherical glass particles were used as easy-to-fluidize particles. Nevertheless,the fluidization was not obtained by this technique. Using the stirring system, a better but stillpoor fluidization was achieved although its quality was improved by adding flowconditioners. An insignificant influence of the stirring speed on fluidization was observed.Four batches containing 1 w/w% of different fluidization additives (two containinghydrophilic additives and two hydrophobic additives) were tested. Fluidization additives wereAerosils? which are nanosize products based on silica. Moreover, the influence of theproportion of additive was tested in six batches containing 0.1, 0.2, 0.3, 0.4, 0.5, and 1 w/w%of the agent which led to the most satisfactory improvement in fluidization behaviour of theglass powder.
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