METHOD OF PRODUCING COMPOUND FERTILIZER Russian patent published in 2017 - IPC C05B11/10 

FIELD: agriculture.

SUBSTANCE: invention relates to agriculture. Method of producing a compound fertilizer involves decomposition of raw materials - ground chalk or limestone with non-concentrated phosphoric acid containing 22–32 % of total P₂O₅, drying the obtained mixture together with recycled dry product and sizing, herewith the obtained mixture is added with washed with cold water from sodium chloride polyhalite ore with the particle size smaller than 2 mm, the mixture is homogenized, the solution obtained by washing from polyhalite ore is evaporated with extraction of sodium chloride, and obtained during cooling the solution sulphate-kalium-magnesium salts are fed for the mixture homogenization prior to drying.

EFFECT: invention simplifies the method of producing the compound fertilizer by adding a mixture with a slowly soluble mineral – polyhalite containing sulphates of potassium, magnesium and calcium, washed from sodium chloride and having prolonged agro-chemical properties, to obtain in the product the specified ratio of P₂O₅:K₂O.

1 cl, 3 tbl, 2 ex