| 摘要 |
<p>The invention relates to a process for producing phosphoric acid, including etching, in an aqueous medium, phosphate rock using sulfuric acid, resulting in the formation of a first dihydrate slurry, in suspension in an aqueous phase, having a free P2O5 content of between 38 and 50% and a free SO3 content lower than 0.5%, converting said first slurry by means of heating, resulting in the recrystallization of the solubilized calcium sulfate so as to obtain a second hemihydrate slurry, and separating the second slurry into industrial phosphoric acid and a hemihydrate cake, characterized in that said process includes, during the etching, adding a fluorine source into the first slurry with a content of 1 to 5 wt % of F relative to the P2O5 contained in the phosphate rock.</p> |
