为明确TiO_2对京唐炉渣性能的影响机理,基于京唐高炉渣的实际成分,通过黏度试验研究了TiO_2对炉渣黏度及熔化性温度的影响;同时利用FactSage热力学软件,计算了不同TiO_2质量分数炉渣的活度、熔化温度,液相区以及炉渣从1500冷却到1000℃时的物相变化。试验结果表明,炉渣的黏度和熔化性温度随着渣中TiO_2质量分数的增加而降低。FactSage计算表明,炉渣中TiO_2活度增大,炉渣的黏度随之减小;TiO_2增多有利于降低炉渣的熔化温度和扩大液相区,但当w(TiO_2)由4.2%变化到5.6%时,炉渣的液相区反而在CaO区域缩小;炉渣结晶相的变化表明渣中TiO_2不宜过多,否则在高温时就容易生成钙钛矿相,从而增大炉渣的黏度,不利于高炉顺行。为满足京唐高炉冶炼对炉渣性能的要求及护炉的需要,炉渣中w(TiO_2)应控制在5.0%以内。
In order to clarify the impact mechanism of TiO_2 on the performance of Jingtang blast furnace slag,based on the actual composition of Jingtang blast furnace slag,the influences of TiO_2 on viscosity and melting temperature of slags were investigated through viscosity test. Furthermore,the activity,liquidus temperature,liquid region and phase change of slag from 1 500 to 1 000 ℃ were calculated by using Fact Sage thermodynamic software. The viscosity experimental result indicates that the viscosity and melting temperature of slag decrease with the increase of mass percent of TiO_2.The calculation results from Fact Sage show that the viscosity decreases with the increase of TiO_2 activity;the increase of mass percent of TiO_2 could reduce the liquidus temperature and expand the liquid region in MgO and Al_2O_3 region,however the slag liquid region in Ca O region isreduced when TiO_2 changes from 4.2% to 5.6%. The transformation of the crystalline phase indicatesthat the perovskite is easy to generate at high temperature when TiO_2 is too much,which can increase the viscosity of the slag and it is not conducive to the blast furnace operation. In order to ensure the fluidity of Jingtang slag and meet the requirement of furnace maintenance,the mass percent of TiO_2 in slag should be controlled within 5%.