Experimental Study On New Process Of Gas-based Direct Reduction-Electric Furnace Smelting Separation For Vanadium-Titanium Magnetite

Vanadium and titanium are national strategic resources in our country, and utilizing vanadium-titanium magnetite efficiently is laid in the medium-term and long-term improvement plans. Because of the prosperities including poor, fine, scattered and mixed, the activity of titanium slag gained from the present mineral processing and the traditional "BF-BOF" technique shows low. Besides the grade of vanadium slag is relatively poor. Consequently, it is difficult to recycle useful elements such as vanadium and titanium efficiently, which limits the comprehensive utilization of vanadium-titanium magnetite, restricts the development of economic and leads to plenty of source wasting and serious environment pollution.Aiming at the current key problem of low efficiency and high environment burden, the new technology of gas-based shaft direct reduction-electric furnace smelting applying on vanadium-titanium magnetite is proposed in this study. Firstly, basing on the reasonable process of pellet’s production, the oxidized pellet is prepared with vanadium-titanium magnetite, and the metallurgical properties are also detected. Secondly, through simulating the reductive condition of gas-based shaft, the direct reduction researches have been carried out considering the reduction behavior and reduction swelling of pellet under various temperatures and atmosphere. Finally, the pellet after reduction is sent to carbon tube furnace to smelt, comparing with blast furnace, the feasibility of the new technique is considered.Through this study, the conclusions can be obtained as follows:(1) Oxidized pellet prepared with vanadium-titanium magnetite and1%additional bentonite and roasted20min at1250℃shows good in metallurgical properties including high strength after reduction and good reduction swelling, which can meet the requirements of gas-based direct reduction process.(2) With the increasing of temperature and the content of H2in reduction atmosphere, the reduction rate of oxidized pellet increases gradually. In addition, the reduction temperature and the content of CO in reduction atmosphere are higher, the reduction swelling becomes serious.(3) The pellet after reduction put in graphite crucible is smelt in carbon tube furnace, which can realize the efficient separation of titanium slag and pig iron containing vanadium.(4) The content of TiO2in titanium slag after smelting is39.52%, and the activity shows good. The content of vanadium in pig iron containing vanadium is0.482%, especially the yield reaches above84.256%, which is better than blast. Consequently, the new technology of gas-based direct reduction-electric furnace smelting is an efficient way to achieve the utilization of vanadium-titanium magnetite.