How to prevent granule cracking during the drying stage of a bio-organic fertilizer production line.
Granule cracking in bio-organic fertilizer production lines is primarily caused by excessive moisture gradients between the granule's interior and exterior, rapid temperature rises, improper hot air velocity, and insufficient granule strength. Optimization can be achieved simultaneously across four areas: granulation pre-treatment, drying temperature control, equipment adjustment, and staged processing. I. Strictly control moisture content at the granulation outlet and minimize moisture gradients. The moisture content of wet granules should be maintained between 26% and 30%. If moisture is too high, the surface loses water and shrinks rapidly during drying, while internal moisture vaporizes and expands, causing the granules to crack; if moisture is too low, the granules lack structural integrity and are prone to breaking during transport and drying. During granulation, appropriate binders—such as bentonite, humic acid, or starch—should be added to enhance granule density and tou...