Process for producing a granular slow-acting nitrogenous fertilizer

摘要

A process for producing a granular slow-acting nitrogenous fertilizer, which comprises blending an aqueous methylol urea solution to a urea-isobutyraldehyde condensate powder or a mixture thereof with a urea-formaldehyde condensate powder, and granulating the resulting blend while subjecting the methylol urea to dehydration condensation under an acidic condition to form a urea-formaldehyde condensate.