METHOD FOR PRODUCING FERTILIZER Russian patent published in 2006 - IPC C05B11/08 C05B17/00 C05D9/02 C05G3/04 

FIELD: fertilizers.

SUBSTANCE: invention relates to technology for preparing fertilizers from the manufacture waste. Proposed method involves mixing the spent sulfuric acid etching solution and powdered phosphorite taken in the mass ratio = 1:0.5 to the homogenous mass with addition of perlite sand for granulation and taken in the amount 20-50% of the mixture mass, and the mass is stirred for 0.5-0.75 h. For separating into layers of the reaction mass and preparing granules the drying process is carried out at temperature 110-130°C to obtain granules with diameter 4-6 mm. The trace element-containing phosphorite-base fertilizer shows the meliorating and insecticide-fungicide properties. The cost of fertilizer is reduced based on utilization of etching solutions.

EFFECT: improved preparing method.