The Xichang Modified Blast Furnace Titanium Slag Titanium Pilot Study

In Panzhihua —Xichang area, the titanium dioxide which associated with themagnetite containing vanadium and titanium accounts for about 97. 54% of all thetitanium resources in our country , about 37.02% of those of the world, onlyabout half of the titanium dioxide enters into the magnetic separation tailingand has been recovered partly, while the other half of the titanium dioxide lostas perovskite form in the smelting iron slag. As the particle size ofdissemination of perovskite in this part of smelting iron slag is fine anddispersible, the average crystal grain is only about 10 microns, and themonomeric dissociation is difficult. Therefore, there is still no very goodmeans to recycle the titanium in the smelting iron slag. To solve the titaniumrecycling problem in the smelting iron slag will have extremely significancefor both enterprise's economic benefit and the titanium resources recycling.According to the specific request of Xichang company about the smelting ironslag containing the titanium, Kunming University of science and technology hasaccepted this experimental task, which have drawn support the metallurgy methodfrom Northeastern University by modifying the perovskite crystal characteristicof the smelting iron slag before mineral processing, and made its crystal grainsize grow to about 80 microns. The appearance of crystal becomes columnarly,massive from the original dissemination asterism shape and the fog shape, whichhas created the condition for concentrating titanium mineral from the slag.First, the conventional flotation method was used in the test, and pilot studies about the smelting iron slag included selective test of collectors, selective test of regulators , condition test of roughing , tests of concentrating , scavenging, open circuit and closed circuit. In the situation of TiO₂ grade 16. 61% in the smelting iron slag, if only one roughing, the rough concentrate containing about 26% TiO₂ with a recovery of 60⁶6% can be obtained . When adopting single-stage open circuit as one roughing and two scavengings after grinding and second-stage closed circuit as five concentrates and twoscavengings, titanium concentrate containing 34.08% TiO2 with a recovery of 32.93% and tailings containing 10.10% titanium with a loss of 28.85% can be obtained. Therefore, the indication is not satisfying when adopting conventional flotation to recycle perovskitePretreating was applied to modify the surface of rough concentrate in the single-stage by the mixed reagent YZ which can selectively resolve the ore surface' s Ca2+. After pretreatment, the inhibitory action which perovskite suffered was greatly weakened because Ca2+ of the perovskite particles surface were very few. However, after gangue was pretreated, There were still many Ca2+ on its surface, in addition, there were massive Mg2+ and other irons were prevented from acting with collectors attribute to the massive adsorption by the inhibitor. When adopted the closed circuit as "two concentratings and one scavenging " after pretreatment, the titanium concentrate containing 38. 36% TiO2 with a recovery of 45.04% can be obtained. After the pretreatment, when utilized the closed circuit as "three concentratings and one scavenging" , titanium concentrate grade maintained between 34% and 37%. On the base of "three concentratings and one scavenging" , all middling returned to mix with rough concentrate and pretreated again, the titanium concentrate containing 40. 04% TiO2 with a recovery of 38.54% and tailings containing 9.84% TiO2 with a loss of 34.84% have been obtained.In the last part, the theory of flotation of perovskite and the reasons why to recover perovskite from modified smelting iron slag was still difficult about Xichang company were analyzed. It was pointed the main reason is that perovskite and gangue have the similar active characteristic. The reason why pre-treating bettered the perovskite flotation is that YZ reagent can selectively resolve the mineral surface' s Ca2+, which greatly weakened the depression of perovskite, however, the depression of the gangue was still fairly great, so the floatability difference between the perovskite and the gangue was expanded.