Double superphosphate (Ca(H2PO4)2-H2O) in contrast to simple superphosphate has a high content of assimilable phosphorus in terms of P2O5-42-49% and doesn’t contain gypsum. Phosphorus i presented in this fertilizer in the form of water-soluble monocalcium phosphate Ca(H2PO4)2-H2O and a small amount of free phosphoric acid (2.5-5.0%).
In the manufacturing process of double superphosphate apatite (or phosphorite) is treated with sulfuric acid. It’s taken more than in the production of simple superphosphate, in order to obtain not a monocalcium phosphate, but phosphoric acid, which is used for new portion of the raw material treatment. And as a result double superphosphate is obtained.
The product is produced in granular form.