The demand for dry products in granular form is increasing. This is mainly owing to the fact that granules are non-dusty and easy to handle, thus enabling ever stricter environmental requirements to be met. By combining the spray drying and fluid bed technologies, GEA has developed a continuous process for producing granular products, i.e. the SPRAY FLUIDIZER™. It is an efficient solution for the chemical industry in the production of high-strength products such as ceramic proppants, sulphate, chlorides organic salts and organic acids.
The SPRAY FLUIDIZER™ facilitates a continuous process where the desired mechanism of particle growth is layering and simultaneous drying of the liquid feed. It combines the spray drying and fluid bed technologies, as the evaporation starts when the liquid feed material is atomized and before the particles can adhere to the agglomerates or granulates of the fluidized powder layer in the Fluid Bed.
The feed is atomized by means of nozzles and sprayed into a fluidized product layer. The granules are continuously withdrawn from the Fluid Bed through a rotary valve maintaining a constant level of the fluidized layer. By subsequent screening, granules of desired particle sizes are discharged from the unit, while any oversized particles can be milled and recycled together with undersized particles and fines recovered in a Cyclone and/or Bag Filter Thus, all product material discharged from the plant will be of the desired particle size.
A plug-flow fluid bed is applied for second-stage drying and cooling.