METHOD FOR PRODUCING CONTROLLED-RELEASE FERTILIZER COATED WITH POLYURETHANE

摘要

A method for producing controlled-release fertilizer coated with polyurethane is provided, wherein granular fertilizer is preheated under fluidized state in a fluidized bed; the surface of the granular fertilizer is pretreated after liquid paraffin being atomized; polyol and isocyanate are mixed in a nozzle, then atomized and sprayed onto the surface of the granular fertilizer; after the reaction materials are added, liquid paraffin is added for surface release treatment.