All phosphate fertilizers are obtained by extraction from minerals containing the anion PO43-. In few cases, fields are treated with the crushed mineral, but more frequently further soluble salts are produced by the chemical treatment of phosphate minerals. Phosphate-containing minerals are often referred to collectively as phosphate rock. Phosphate rock naturally weather to release phosphate ions over long periods of time. This plays a key role in regulating the natural phosphorous cycle. The natural phosphorous cycle The phosphorus cycle begins in the Earth’s crust where phosphorus-containing rock, phosphorite, is weathered by processes of wind, rain, freezing and thawing until it eventually becomes soil. This can take many millennia to occur. Once in the soil, part of the phosphorus is absorbed by plants. Phosphorus is then transferred from plants to other living organisms via the food chain. The phosphorous is returned to the soil …show more content…
Phosphate rock is used to manufacture most commercial fertilizers. Phosphates mined were once sediments at the bottom of ancient seas. The world’s largest reserves of high-quality phosphate and their estimated reserves for 2012 are Morocco 50 000 MMt, China 3700 MMt and US 1100 MMt. After being mined, phosphate rock is separated from particles of sand and clay and sent to a processing plant. These processes are usually wet to enable material transport and to reduce dust. Phosphate rock is THEN mixed with sulphuric acid to produce weak phosphoric acid. This phosphoric acid is mixed with various other minerals to produce liquid or solid fertilizers. Theses process vary with respect to the fertilizer being produced. Frequently manufactured fertilizers are triple superphosphates (SSP, TSP) and ammonium phosphates (MAP, DAP). By 2015, phosphate fertilizer production is expected to be 57.6 million tons. In 2014 the world consumed an estimated 42.2 Mt of phosphorus