How are phosphate fertilizers and other products produced?
Phosphate is found in underground ore deposits which contain phosphate rock. This is reacted with a mixture of phosphoric and sulfuric acid to produce phosphoric acid, the feedstock for other products. Phosphoric acid may be reacted with ammonia and granulated to produce the solid fertilizer DAP, concentrated by evaporation to produce merchant grade phosphoric acid or further evaporated to produce superphosphoric acid. It may also be reacted with limestone or phosphate rock to produce animal feed products, or purified by solvent extraction to produce industrial grade phosphoric acids.
