Study On The Technology Of Titanium - Containing Slag Modification - Refining Titanium Concentrate

There are more than 50 million tons slag, which content titanium about 17%-40%, in China. Literature reported that chemical dissolution method and modified mineral separation method are the main methods of treating the titanium bearing, but both of them can’t make the slag become resource. The treatment of titanium containing slag was studied in this paper, which will be used a method of recrystallization gravity separation.The analysis of thermodynamic and crystallization process shows that the reaction of mineral dissociation and recrystallization of titanium containing slag can be occurred in the solution of FeSO4-Fe2(SO4)3-H2SO4, and the hydrothermal condition is better than the normal temperature and atmospheric conditions. The study of the solid minerals of hydrothermal reaction shows that using the method of gravity classification can get the titanium containing minerals and non titanium containing minerals from the solid minerals.The process conditions of hydrothermal modification was studied. In the study, the concentration of FeSO4 and Fe2(SO4)3, PH, the temperature of the reaction and the time of heat preservation was investigated for the influence of the content of TiO2 in the modified solid mineral separation concentrate. The result shows that the content of TiO2 in the concentrate will increase first and after that it has anapproximate constant with the increase of the FeSO4 and Fe2(SO4)3 concentration and heat preservation time. And with the increase of pH,the content of TiO2 will remain unchanged first and then fast decrease. And the content of TiO2 will increase first and then decrease with the increase of the reaction temperature. After optimization of the FeSO4 and Fe2(SO4)3 concentration and the heat preservation process conditions, we can get the best conditions of the hydrothermal modification are[FeSO4]=0.67molL-1, [Fe2(SO4)3]=0.16mol·L-1, pH=2, the reaction temperature t=150 ℃, the heat preservation time T=3.44h. Under these conditions, the content of TiO2 and the TiO2/CaO can be increased, which is from the original slag 41.92%,5.79 increased to 50.55%,14.52. The yield of concentrate was 54.55%. And the content of TiO2 can be lowed to 15.21% in the tailings, and the yield of the tailings is 28.30%.The study on recycling of hydrothermal reaction filtrate and middling product shows that the whole process can realize the closed circuit circulation with recycling the filtrate of hydrothermal reaction after supplementing the FeSO4 and Fe2(SO4)3 and making the middling product to enjoy in the hydrothermal reaction again after mixing it to the original slag. The optimum mix ratio of middling product and the original slag is 1:4.