二氧化钛改质对含磷转炉渣中磷富集行为的影响

为了有效富集含磷转炉渣中磷，通过TiO₂熔融改质研究了磷富集行为，对TiO₂改质过程进行了热力学探讨，同时对实验炉渣进行磁选分离提取了富磷相.在1623 K条件下，随着渣中TiO₂含量的增加，渣中先期析出的n2CaO·SiO₂-3CaO·P₂O₅（以下简记nC₂S-C₃P）固溶体与TiO₂不断反应析出CaSiTiO₅、CaTiO₃和高磷固溶体（n'C₂S-C₃P，n'2S-C₃P固溶体会随着TiO₂含量的增加而逐渐减少甚至消失，如渣中TiO₂含量进一步增加或过量，前述反应生成的高磷固溶体（n'C₂S-C₃P）继续与TiO₂反应，从而使富磷相中磷含量进一步提高.经350mT磁场强度下磁选后，改性后的渣中收集到的非磁性物较原渣提高了23.84%，P₂O₅分配比由0.96增加到2.92，分离的非磁性物占炉渣总量的65.43%，渣中74.46%的磷进入收集的非磁性物中，实现了绝大部分磷元素的回收利用. 

Influence of titania modification on phosphorus enrichment in P-bearing steelmaking slag

In order to effectively enrich phosphorus in converter slag,phosphorus enrichment was studied by TiO₂ modification,the TiO₂ modification process was discussed according to thermodynamic analysis,and the phosphorus-rich phase was separated from experimental slag by magnetic separation. It is found that CaSiTiO₅,CaTiO₃ and high phosphorus solid solution(n'C₂S-C₃P) form by a continuous reaction of n2CaO·SiO₂-3CaO·P₂O₅(nC₂S-C₃P for short,n>n') solid solution precipitated in the slag and TiO₂at 1623 K. The early precipitated solid solution(nC₂S-C₃P) decreases with the increasing TiO₂ content,even disappears. If the addition of TiO₂ increases or is excess in the slag,the high phosphorus solid solution(n'C₂S-C₃P) that forms by the above mentioned reaction will continue to react with TiO₂ to produce CaSiTiO₅ and CaTiO₃,and then phosphorus content in the phosphorus-rich phase increases.Through magnetic separation under a magnetic flied intensity of 350 mT,the amount of collected non-magnetic substance in the slag modified by TiO₂ increases by 23.84% compared with the original slag,the distribution ratio of P₂O₅ enlarges from 0.96 to 2.92,the amount of separated non-magnetic substance is 65.43% of the total of the modified slag,74.46% of phosphorus in the modified slag is entered into collected non-magnetic substance,and thereby most phosphorus is recycled.