Solidification and Stabilization of Fluorine and Phosphorus in Phosphate Mine Tailings and the Mechanism of F and P Fixation During Soilization

Abstract

Researching methods for harmless and resourceful utilization of phosphate mine tailings presents a new approach to addressing phosphate mine tailings pollution. This study selected a formulation of agents for solidifying fluorine and phosphorus in phosphate mine tailings, investigating the solidification effects of phosphorus and fluorine under different temperatures and time, as well as the changes in the physicochemical properties of phosphate mine tailings. Solidified phosphate mine tailings soilization results showed that phosphate mine tailings: polymerized aluminum sulfate: ferrous sulfate=96.5 : 1.75 : 1.75 worked well, with a leaching toxicity of fluorine of 0.9569 mg/L, a fixation rate of 74.92 %, and a retention of water‐soluble phosphorus of up to 82.75 %. At 25 °C and 28 days of cultivation, the leaching toxicity of phosphate mine tailings treated with the solidifying agent was less. Solidified phosphate mine tailings were again added with solidifying agent to solidify phosphorus and fluorine, and the stabilization rate of fluorine reached 90.08 %. The “soil” cultivated for 28 days had an optimal structure of nutrients, and the germination rate of cabbage seeds was 83.33 %. This study demonstrates the possibility of using phosphate mine tailings as planting soil, and provides a useful theoretical basis for the fluoride fixation mechanism in phosphate mine tailings.