关键词: 流化;微硅粉;除碳;性能

Abstract: Fluidied bed method was used to removing carbon from silica fume .The optimal process condition was the reaction temperature of 800 ℃ and reaction time of 3 h through single factor experiments.In this condition, the content of silicon dioxide in silica fume increased from 75.64％ to 83.16％, the content of free carbon in silica fume drops from 4.14％ to 0.15％, removal rate can reach 96.38％.The silica fume before and after fluidization were analyzed by X -ray powder diffraction, scanning electronic microscopy, brunauer-emmett-teller and other tests.The results show that the silica fume after fluidization is still non-crystalline structure and the particles are smooth and have a regular spherical shape.After being fluidized,the particle size of silica fume is increased , the specific surface area is slightly reduced because of fine particles are taken out in the process of fluidization .The fluidity of silica fume after fluidization is better than that before fluidization , it is more conducive to industrial production.

Key words: fluidization;silicon fume;carbon removal;property