The enrichment behavior of phosphorus in CaO-SiO2-FeOx-P2O5 slag was studied by making an investigation on the distribution of phosphorous content in the CaO-SiO2-FeOx-P2O5 molten slag.The research results showed that...The enrichment behavior of phosphorus in CaO-SiO2-FeOx-P2O5 slag was studied by making an investigation on the distribution of phosphorous content in the CaO-SiO2-FeOx-P2O5 molten slag.The research results showed that the 2CaO·SiO2 solid particles existing in molten slag were the condensation sites for the phosphorus enrichment.The enrichment process of phosphorus in the molten slag can be recognized as three substeps：mass transfer of phosphorus from bulk slag to the surface of 2CaO·SiO2 particle,superficial solid solution reaction of phosphorus around the 2CaO·SiO2 particle,and diffusion of phosphorus through the product layer of 2CaO·SiO2-3CaO·P2O5 solid solution to the inner of 2CaO·SiO2 particle.Moreover,higher temperature is favorable to the phosphorous enrichment from molten bulk slag to the 2CaO·SiO2 particles.展开更多
A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly conce...A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly concentrated in the 2CaO SiO2-3CaO P2O5 solid solution,the recovery of P from dephosphorization slag primarily depends on the separation of the solid solution from other phases.The distribution ratios of P2O5 between solid solution and liquid phase in the CaOSiO2-FeO-P2O5-Nslag system were investigated.The results indicated that the addition of Na2O facilitated the enrichment of P2O5 in the solid solution because it increased not only the distribution ratio of P2O5 but also the mass fraction of the solid solution.The distribution ratio of P2O5 was independent of the P2O5 content in slag.A higher P2O5 content in slag resulted in higher P2O5 and Na2O contents in the solid solution.The distribution ratio of P2O5 increased with the total Fe content in the liquid phase,regardless of the valence of Fe.An increase in the FeO content in slag brought a higher P2O5 content in the solid solution.As slag basicity increased,the distribution ratio of P2O5 increased,but the P2O5 content in the solid solution decreased.展开更多
Based on the thermodynamic calculation, the mole ratio of CaO to SiO 2, temperature and A/S of bauxite have a profound influence on the mole ratio of 2CaO·SiO 2 to CaO·SiO 2 in sinter. CaO·SiO 2 and β ...Based on the thermodynamic calculation, the mole ratio of CaO to SiO 2, temperature and A/S of bauxite have a profound influence on the mole ratio of 2CaO·SiO 2 to CaO·SiO 2 in sinter. CaO·SiO 2 and β -2CaO·SiO 2 appear stable in caustic solution but unstable in soda solution, and CaO·SiO 2 is more stable than β -2CaO·SiO 2 under the same leaching condition. Compared with the conventional sinter, the rate of alumina extraction of the new sinter is large and the secondary reaction is restricted in the leaching, which might be mainly due to the more content of CaO·SiO 2 in sinter and better stability of CaO·SiO 2 in leaching.展开更多
基金Item Sponsored by National Natural Science Foundation of China/Joint Fund for Iron and Steel Research(50874130)National Natural Science Foundation of China(50974034)
文摘The enrichment behavior of phosphorus in CaO-SiO2-FeOx-P2O5 slag was studied by making an investigation on the distribution of phosphorous content in the CaO-SiO2-FeOx-P2O5 molten slag.The research results showed that the 2CaO·SiO2 solid particles existing in molten slag were the condensation sites for the phosphorus enrichment.The enrichment process of phosphorus in the molten slag can be recognized as three substeps：mass transfer of phosphorus from bulk slag to the surface of 2CaO·SiO2 particle,superficial solid solution reaction of phosphorus around the 2CaO·SiO2 particle,and diffusion of phosphorus through the product layer of 2CaO·SiO2-3CaO·P2O5 solid solution to the inner of 2CaO·SiO2 particle.Moreover,higher temperature is favorable to the phosphorous enrichment from molten bulk slag to the 2CaO·SiO2 particles.
基金This work was financially supported by the National Natural Science Foundation of China(Nos.51704010,51604003,U1760117)Key Laboratory Open Project Fund of Metallurgical Emission Reduction and Resources Recycling(Anhui University of Technology)Ministry of Education(JKF18-02).
文摘A multi-phase slag containing Na2O is potential to efficiently dephosphorize high-P hot metal.After dephosphorization,the generated slag with high P2O5 content is regarded as a P resource.Because P2O5 was mainly concentrated in the 2CaO SiO2-3CaO P2O5 solid solution,the recovery of P from dephosphorization slag primarily depends on the separation of the solid solution from other phases.The distribution ratios of P2O5 between solid solution and liquid phase in the CaOSiO2-FeO-P2O5-Nslag system were investigated.The results indicated that the addition of Na2O facilitated the enrichment of P2O5 in the solid solution because it increased not only the distribution ratio of P2O5 but also the mass fraction of the solid solution.The distribution ratio of P2O5 was independent of the P2O5 content in slag.A higher P2O5 content in slag resulted in higher P2O5 and Na2O contents in the solid solution.The distribution ratio of P2O5 increased with the total Fe content in the liquid phase,regardless of the valence of Fe.An increase in the FeO content in slag brought a higher P2O5 content in the solid solution.As slag basicity increased,the distribution ratio of P2O5 increased,but the P2O5 content in the solid solution decreased.
文摘Based on the thermodynamic calculation, the mole ratio of CaO to SiO 2, temperature and A/S of bauxite have a profound influence on the mole ratio of 2CaO·SiO 2 to CaO·SiO 2 in sinter. CaO·SiO 2 and β -2CaO·SiO 2 appear stable in caustic solution but unstable in soda solution, and CaO·SiO 2 is more stable than β -2CaO·SiO 2 under the same leaching condition. Compared with the conventional sinter, the rate of alumina extraction of the new sinter is large and the secondary reaction is restricted in the leaching, which might be mainly due to the more content of CaO·SiO 2 in sinter and better stability of CaO·SiO 2 in leaching.
