摘要 |
Anti-caking agent is thoroughly distributed upon particulate hygroscopic materials, e.g., particulate inorganic salts such as potassium chloride and sodium chloride, by contacting an agitated stream of the particulate material with an aqueous dispersion of anticaking agent and then passing the treated material through a fluid bed of the treated particulate material. The pretreated particulate hygroscopic material is typically warm, i.e., has a temperature above 25 DEG C., and is cooled in the fluid bed which is fluidized with dehumidified, fluidizing gas having a temperature lower than the treated particulate hygroscopic material entering the bed. Cooled particulate hygroscopic material having a coating of anticaking agent distributed substantially uniformly over the surface of the particles and having a water content substantially the same as the pretreated warm particulate material is removed from the fluid bed.
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