Manufacture of fertiliser

A method of manufacturing phosphate fertilizer that comprises dicalcium phosphate, the method comprising:

• providing milled phosphorus-containing rock having a total phosphorus content of at least about 14.2% P by weight;
• mixing the milled phosphate-containing rock with a mineral acid in a reaction vessel to produce a superphosphate product;
• and
• mixing the superphosphate product with a calcium-source reverting agent and a magnesium-source reverting agent to produce a reverted product, the calcium-source reverting agent comprising at least about 20 to about 50% by weight of the total amount of reverting agent of calcium oxide with a calcium carbonate equivalence of at least about 134%, and the magnesium-source reverting agent providing a magnesium source and comprising at least about 50 to about 80% by weight of the total amount of reverting agent of magnesium source with a calcium carbonate equivalence of at least about 80%, to produce a granulated cured reverted product having a product yield of at least about 1.77 and a moisture content of less than 3%.

A method of manufacturing phosphate fertilizer comprising dicalcium phosphate, the method comprising:

• providing milled phosphate-containing rock;
• mixing the milled phosphate-containing rock with a mineral add in a reaction vessel to produce a superphosphate product;
• and
• mixing the superphosphate product with a calcium-source reverting agent and a magnesium-source reverting agent to produce a reverted product, the calcium-source reverting agent comprising at least about 20 to about 50% by weight of the total amount of reverting agent of calcium oxide with a calcium carbonate equivalence of at least about 134%, and the magnesium-source reverting agent providing a magnesium source and comprising at least about 50 to about 80% by weight of the total amount of reverting agent of magnesium source with a calcium carbonate equivalence of at least about 80%, to produce a granulated cured reverted product having a total phosphorus content of at least about 7.5% P by weight.