METHOD OF SEPARATING AND RECOVERING PHOSPHORUS FROM DEPHOSPHORIZATION SLAG CONTAINING PHOSPHORUS AT HIGH CONCENTRATION

摘要

To provide a method for separating and recovering phosphorus from dephosphorization slag containing phosphorus at high concentration in which phosphorus is separating efficiently from the dephosphorization slag containing phosphorus at high concentration by a leaching method and phosphorus is recovered from the leachate.SOLUTION: A dephosphorization slag containing 5 to 12 mass% of phosphoric anhydride (PO) and containing 2 mass% or more of at least one of NaO and KO is immersed in an aqueous solution having a pH of 5.0 to 6.5, to leach phosphorus into the aqueous solution, and then phosphorus is recovered from the aqueous solution by adjusting the pH of the aqueous solution to 9.5 or more after separating and removing residue.SELECTED DRAWING: Figure 1