用后铁水脱硫搅拌器的再生处理

Regeneration Process of Used Molten Iron Desulfurization Stirring Equipment

对用后KR法铁水预处理脱硫搅拌器浇注料,采用破碎、碾压、筛分及酸溶液浸泡的方式,进行再生利用研究。利用SEM分析了用后料及再生料微观结构。研究了碾压时间、酸溶液浸泡时间对再生料性能的影响。得出以下结论:用后料经破碎后颗粒料的体积密度介于2.45~2.62 g/cm^3之间,假颗粒含量大于50%,破碎后的物料质量差,不宜直接再利用;破碎后的物料分粒级碾压,碾压25~40 min较适宜,颗粒体积密度可达到2.70~2.80 g/cm^3,假颗粒含量降到10%~15%;再生颗粒料的SEM图显示,由于碾压过程受到压应力的作用,部分晶粒及间隙产生裂纹,会降低再生制品结构强度,不利于再生利用,因此,对用后料的碾压时间不宜过长;盐酸溶液浓度越高,消除假颗粒的速度越快;浸泡时间越长,假颗粒处理得越彻底;盐酸溶液浓度一定时,反应速率前期较迅速,后期缓慢;浸泡60 h时,假颗粒的含量可以降到2%~2.5%左右。

Useing the used castable of KR pretreatment of hot metal desulfurization stirrer as material and adopts the methods include crushing, grinding, screening and immersing in the acid, which proceed the regeneration research. Studying SEM method can be used to analyze mineral composition, microstructures of material and regeneration material. Respectively this paper researches on the influence of grinded time, the immersed time in acid on the quality of regeneration material. The conclusion includes, after crushed, the B. D of used material particle is between 2.45 and 2.62 g/cm3 and the content of false particle is above 50%. The quality of material is worse after crushing, it is not suitable for direct reuse. Materials are rolled with different particle size after crushed, the best time is between 25 rain and 40 min, at this point the B. D up to 2.70-2.80 g/cm3 , the content of false particle down to 10%-15%. SEM image of regeneration granular material shows, due to the pressure of rolling process, part of the grain and the gap produced cracks, which will reduce the structure strength of regeneration products, and it is unfavorable for regeneration. The higher hydrochloric acid concentrate, the faster false particles are eliminated. The longer immersion time takes, the more thoroughly false particles are treated. Hydrochloric acid concentration is constant, the early stage of the reaction rate is quick, and later it becomes much slow. The content of false particle can drop 2.0%-2.5% after immersed 60 h.