Recycling of Local Phosphate Waste - mineralized Mass into Activated Phosphorus Fertilizers

Abstract

The manuscript provides the results of the process of obtaining activated phosphorus fertilizer (APF) by nitric acid processing of mineralized mass (MM) of phosphate waste, which formed during the sorting stage of thermal beneficiation of Central Kyzylkum (CK) phosphorites. For experiments was used MM with content 14.60% P2O5total(t.).; 3.07% P2O5acceptable by citric acid (ac.c.a.); 43.99% CaOt.; 1.01% MgO; 14.11% CO2; 1.04% Al2O3; 0.89% Fe2O3; 1.58% SO3; 1.30% F; 1.02% H2O; CaO:P2O5 – 3.01 and 10.82% insoluble residual. The optimal concentrations and norms of nitric acid have been determined. Phosphorus fertilizer suspensions were neutralized with Ca(OH)2 suspension in order to prevent P2O5 from passing into the solution. APF obtained in optimal parameters has the following composition (weight, %): 20.42-20.58 P2O5total(t.); 11.02-11.72 P2O5ac.c.a.; 38.87-39.01CaOt.; 23,39-24,48 CaO ac.c.a.. The degree of transition of P2O5 to liquid phase is 2.02-2.06%.