Dephosphorization slag is one of the bulk solid wastes generated from steelmaking.If P is effectively removed from dephosphorization slag,a phosphate source which can substitute for phosphate rocks is obtained;meanwhi...Dephosphorization slag is one of the bulk solid wastes generated from steelmaking.If P is effectively removed from dephosphorization slag,a phosphate source which can substitute for phosphate rocks is obtained;meanwhile,the tailings can be reutilized as a feedstock in steel plant.To realize the integrated utilization of dephosphorization slag,selective leaching was applied for removing the P-bearing mineral phase from dephosphorization slag.Alkaline oxide was added as the slag modifier and HCl was selected as the acid lixiviant.The P selective leaching from dephosphorization slags modified by Na_(2)O or K_(2)O was studied at different pH values.By modification,the mass fraction of P in the_(2)CaO∙SiO_(2)–3CaO∙P_(2)O_(5)phase increased,indicating that it was in favor of P_(2)O_(5)enrichment.As the Na_(2)O or K_(2)O content increased,the P leaching ratio from slag increased at pH 4,reaching about 80%,and that of Fe was nearly zero.Na_(2)O and K_(2)O modification played a similar role in enhancing the P leaching.The effect of alkaline oxide modification became weak at pH 3,and the slag without modification also realized a good P selective leaching in the HCl solution.To facilitate the P removal,the leaching of Fe from dephosphorization slag needs to be restrained.展开更多
基金the National Natural Science Foundation of China(52104326)the Fundamental Research Funds for the Central Universities(N2225016)+1 种基金the Anhui Special Support Plan(T000609)the Distinguished Professor of the Wanjiang Scholars Project.
文摘Dephosphorization slag is one of the bulk solid wastes generated from steelmaking.If P is effectively removed from dephosphorization slag,a phosphate source which can substitute for phosphate rocks is obtained;meanwhile,the tailings can be reutilized as a feedstock in steel plant.To realize the integrated utilization of dephosphorization slag,selective leaching was applied for removing the P-bearing mineral phase from dephosphorization slag.Alkaline oxide was added as the slag modifier and HCl was selected as the acid lixiviant.The P selective leaching from dephosphorization slags modified by Na_(2)O or K_(2)O was studied at different pH values.By modification,the mass fraction of P in the_(2)CaO∙SiO_(2)–3CaO∙P_(2)O_(5)phase increased,indicating that it was in favor of P_(2)O_(5)enrichment.As the Na_(2)O or K_(2)O content increased,the P leaching ratio from slag increased at pH 4,reaching about 80%,and that of Fe was nearly zero.Na_(2)O and K_(2)O modification played a similar role in enhancing the P leaching.The effect of alkaline oxide modification became weak at pH 3,and the slag without modification also realized a good P selective leaching in the HCl solution.To facilitate the P removal,the leaching of Fe from dephosphorization slag needs to be restrained.
