Improved method for producing granular compound fertilizer by drum granulation

The invention relates to an improved method for producing a granular compound fertilizer by drum granulation. The method comprises the following steps: producing granule nucleuses with the fineness of0.5-3mm by using compound fertilizer raw materials; grinding one part of the compound fertilizer raw materials to powdered raw materials having the granularity of 100 meshes or less; adding the granule nucleuses into a feeding end of a drum granulator at a stable speed; performing uniform blanking or multi-point blanking on the ground raw materials in the drum granulator along an axis direction by virtue of distribution machinery, enabling water, vapor, slurry or other granular additives to enter a material bed in the granulator by virtue of nozzles arranged at multiple points along the axisdirection of the drum granulator, and uniformly distributing the materials on the surfaces of the granules in the material bed; and screening qualified granules from materials at the outlet of the granulator, and drying the gr