TH269A - Phosphate fertilizers and their production methods - Google Patents

Abstract

Phosphatic fertilizers consist of a mixture of water-soluble phosphorus compounds, phosphorus compounds insoluble in water but soluble in weak organic acids, and phosphorus compounds that are insoluble in both water and weak organic acids. Phosphatic fertilizers are produced by reacting sulfur trioxide (which may be in a mixture with other gases) with a phosphoric raw material. The sulfur trioxide, as a mixture with other gases, enters the reaction area at a temperature below 100°C. The reaction between the phosphorus-containing raw material and the sulfur trioxide occurs while the temperature automatically adjusts to 180-250°C within 10-30 minutes.

Claims (4)

1. Phosphate fertilizers are characterized by their composition of a mixture of water-soluble phosphorus compounds, phosphorus compounds soluble in weak organic acids but insoluble in water, and phosphorus compounds insoluble in both weak organic acids and water. 2. Phosphate fertilizers as defined in Patent 1 are characterized by containing 5-20% water-soluble phosphorus compounds of the total phosphorus content, 30-60% water-insoluble but weakly soluble phosphorus compounds of the total phosphorus content, and 15-35% water-insoluble and weakly soluble phosphorus compounds of the total phosphorus content. 3. The method for producing phosphate fertilizer involves reacting sulfur trioxide, which may be in a mixture with other gases, with a phosphorus-containing raw material. This sulfur trioxide is added to the reaction area at a temperature below 100 degrees Celsius, and the reaction between the sulfur trioxide and the phosphorus-containing raw material occurs at a temperature of 180-250 degrees Celsius for 10-30 minutes. 4. The method is defined in claim 3, which is characterized by the ability to adjust the reaction temperature by changing the temperature of the gas introduced into the reaction area (4 claims, 1 page, 0 figures).