超细冶金废弃物硅灰的物理分级研究

The Exploration of Disperse Ultrafine SiO_2 Particles from the Fume Produced during the Manufacturing of Ferroalloy

研究发现,在没有经过压密处理硅灰的物理分散手段中,使用超声震荡的效果明显优于机械搅拌。使用六偏磷酸钠的效果略优于三聚磷酸钠,使用离心的方法可以做到粒度分级。最终,我们得到的最佳工艺为:首先在没有经过压密的硅灰中加入质量比1∶15的水,然后按照硅灰质量的4%加入六偏磷酸钠,经过机械搅拌使之均匀,然后,进行10min以上的超声震荡,最后以800转/min的速度离心20min,得到的悬浮液中200nm以下的二氧化硅颗粒占50%,400nm以下的二氧化硅颗粒占90%。

Through experiments, silica fume without compaction is more suitable for dispersing raw materials. The results of dispersants and ultrasound shaking are much better than that of rabbling. What＇s more, the results of dispersants are the best. However, there are no conflicts a- mong them. Therefore, they can be used at the same time. In terms of Trimeric sodium phos- phate and Six partial sodium, the results of Six partial sodium are little better, so people can se- lect the two ways according to economical aspect in applications. Particle size systematics can be realized by centrifugal method. According to the analysis of the experiments, we can conclude the most suitable procedure, firstly, we should pour a lot of water into silica fume; secondly, we add Six partial sodium whose mass is 4% of that of the silicon fume into the mixture; thirdly, after rabbling, ultrasound shaking should be taken for more than 10 rain; fourthly, eentrifugal method should be taken at the speed of 800 r/rain for 20 rain; finally, we can get 50% silica particles which is smaller than 200 nm and 90% particles which is smaller than 400 nm.