Alkaline decomposition process for producing calcined phosphate fertilizer
AssigneeKali-Chemie Aktiengesellschaft
InventorsUlrich Hauschild, Heinrich Roetger
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Abstract
A process for the production of highly citrate-soluble calcined phosphate fertilizers is disclosed. The process comprises calcinating a mixture which comprises appropriate amounts of calcium phosphates, silicic acid and an alkaline decomposing agent whereby the naturally occurring mineral trona is used as an alkaline decomposing agent. The process is effected in a rotary kiln; the maximum temperature is about 1300.degree. C.
Claims11
In an alkaline high temperature decomposition process for producing a calcined citrate-soluble alkali-containing phosphate fertilizer, which comprises the step of calcining in a rotary kiln at a temperature of between about 900.degree. and 1300.degree. C, a mixture comprising a raw calcium phosphate, an alkali-metal-oxide supplying compound and silicic acid in such amounts that the molar ratio between the phosphate and the alkali metal oxidesupplying compound is equivalent to a per weight ratio P.sub.2 O.sub.5 :Na.sub.2 O of between about 1:0.45 and about 1:0.7 and the amount of silicic acid is sufficient to bind an excess of calcium, the improvement, which comprises said alkali metal oxide-supplying compound, consisting essentially of the naturally occuring mineral trona.
Dependencies are inferred from the claim text.