Investigation of the validity of the similarity criteria for predicting the hydrodynamic behaviour of laterite ores in a high temperature fluidised bed

This study investigates the fluidisation behaviour of laterite ores potentially to reflect high temperature fluidisation. The investigation at high temperature is made difficult by the fact that visualisation of the ore cannot be made. Cold fluidised bed operation that mimics hot conditions has historically been conducted but based on the same superficial gas velocity. That is the cold model is operated at the same gas velocity as the hot unit. A more recent approach is to apply similarity criteria based on dimensionless numbers. This study investigates the applicability of these criteria's to the fluidisation of laterite ores. Particular attention is being drawn to the fact that the above parameters were derived neglecting inter particle forces. Thus if particles should have electrostatic and other cohesive forces, which may vary between the hot and cold system then hydrodynamic behaviour cannot be maintained in both system. This applies particularly for fine particles (Geldart C particles).