| Vanadium-Titanium-Magnetite resources are abundant in Pan-Xi area in China.For more than half-a-century,our country has made remarkable achievements in the smelting technology of V-Ti-magnetite from scratch.While,because of the unique compositio na l characteristics of V-Ti-magnetite: TiO2 wt.% >10wt.% in raw ore,it is needed to add an amount of normal ore to achieve normal smelting when smelting the ore in blast furnace,which will restrict its comprehensive utilization.So improving the ratio of V-Ti-magnet ite in blast furnace is the only way to achieve the comprehensive utilization of the ore,which will lead to a series of problems such as the slag viscous,slag-metal mixture,irregular furnace operation and serious slag foaming phenomenon.When smelting high ratio or full V-Ti-magnetite,serious slag foaming phenomeno n will happen in blast furnace especially in the hearth area.In the field of the research on the foaming phenomenon of high titanium blast furnace slag,previous studies mainly focused on the causes of foam formation and influencing factors of slag,while didn't pay much attention to the foaming process.Based on extensive literature reading and former experiences,we achieve to realtime monitor the foaming phenomenon of high titanium blast furnace slag by using the experimental device which can monitor the foaming phenomenon by the real-time current change.And we explore the mechanism of slag foaming originated from reaction through calculating the physical parameters of the slag.At last,we explored the model to describe slag foaming originated from reaction.The main conclusions are as follows:? In the research,we firstly verify the feasibility of the experimental device.The measured current value is proportional to the height of the slag,so the recorded current value can be used to reflect the degree of foaming.In the repeated experiments at room temperature and high temperature,it can be found that the current value obtained by using Mo sheet as electrode has a linear relationship with the foaming height or depth,and the correlation coefficients reach to much more than 0.9.At the same time,its repeatabilit y can also meet the needs of the experiment.Therefore,it's concluded that the experimental device is feasible.? In the experiments of slag foaming originated from reaction at high temperature,the foaming processes include 3 stages: foam generation stage,foam duration stage,foam elimination stage.? In the study,we found TiO2 content and basicity(CaO/SiO2)has different effects on foaming process.In which,the content of TiO2 has a great influence on the foaming degree: the foaming degree increases greatly with TiO 2 increasing.While basicity mainly influences the foaming time especially the foam duration time: foam duration time increases with basicity increasing.? According to the calculation of the slag physical parameters,for Ti-bearing blast furnace slag,due to the existent of solid particles,with TiO2 increasing and basicity decreasing,viscosity increases,surface tension decreases.While relative to viscosity,the surface tension little changes.? Comparing the experimental results and the calculation results,viscosity has great influence on foaming process: along with viscosity increasing,the foaming degree and foaming time increase obviously.? The electrical conductivity of the slag is also a main factor of the experimental results: the electrical conductivity of the slag increases leads to the initial current increases slightly.? We investigate the slag foaming equation based on the mechanism of bubble accumulating in the slag.In the follow-up study,it is need to do more detail experiments to get more data,and then build a mathematics model for foaming phenomenon caused by chemical reaction of Ti-bearing blast furnace slag. |
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