Separation of Phosphorus from Phosphorus-concentrated Steelmaking Slag

Since 10 million tons of steelmaking slag, which contains a few percent phosphorus, are annually produced, the phosphorus amount in slag is equivalent to annual import volume rock Japan. Therefore, attracting attention as potential resources. Phosphorus-concentrated obtained by dephosphorization reaction between high hot metal and oxidizing at temperature phosphorous comparable that rock. However, because FeO concentration, it difficult use for resources directly. In this work, effects pH, acid type leaching method on dissolution behavior from P-concentrated were investigated. As result, progressed lower was promoted addition citric acid, known chelate former. When nylon mill pot stirring with alumina nitric compared impeller stirring, respectively. By combining citrate leachate, accelerated, pulverized during formation insoluble metal-phosphate inhibited complex ion leached cation citrate. while controlling pH ratio lowered since aluminum ion, supplied crushing ball leaching, constructed secondary products low solubility along other dissolved ions.