METHOD OF PRODUCTION OF COMPLEX FERTILIZER Russian patent published in 2006 - IPC C05B11/08 C05B17/00 C05D9/02 C05G3/04 

FIELD: farming; technology of production of complex fertilizers.

SUBSTANCE: proposed method includes mixing phosphate meal with waste sulfuric acid solution of ferrous metal pickling process at mass ratio of 1:2; then zeolite with grain fraction of 1.5-3.5 mm is added in the amount of 25-45% of mass of mixture, after which mixture is fed to screw drier where granules are formed and dried at temperature of 130-150°C. Fertilizer thus produced possesses ameliorating and insect fungicide properties.

EFFECT: low cost of process; possibility of utilization of picking solutions.