FLUIDISATION OF FINE AND ULTRAFINE POWDERS ASSISTED BY OSCILLATING ELECTRIC FIELDS

摘要

A method is described for improving gas fluidisation of fine and ultrafine powders. A procedure of fluidisation of powders comprising passing a gas flow (4) through a porous plate (5) through a powder bed (6) disposed on said porous plate in a fluidisation chamber (10), the powder bed comprising at least one powder selected from among fine powders comprising primary particles having a typical size between 1 and 20 microns, ultrafine powders comprising primary particles having a typical size between 1 and 1000 nm, and mixtures thereof; and simultaneously subjecting the powder bed to agitation treatment to reduce the effect of cohesion between said particles, comprising applying to said bed at least one oscillating electrical field (9). The movement induced by the external oscillating field results in more uniform fluidisation and greater expansion of the fluid bed.