KR法铁水脱硫剂利用技术研究进展

Research progress on efficiency techniques for desulfurization flux in hot metal with KR process

KR法(又称机械搅拌法)较喷吹法,在实现铁水深脱硫和脱硫稳定性方面具有明显优势。然而,在搅拌过程中由于发生脱硫剂团聚现象,存在石灰脱硫利用率不高的问题。综述了近些年在提高KR法铁水脱硫石灰利用率方面的研究成果。利用自由CaO在冷却过程中引起的粉化现象可以实现脱硫渣循环利用,但通过加料方式和动力学条件的改善,控制石灰的团聚程度更具有研究价值。尤其是借鉴化工领域研究成果,在铁水罐内壁对称设置2块挡板,抑制了在搅拌头上方中心涡流区的形成,明显减小了脱硫剂在熔池液面上的聚集,改善了脱硫剂与铁水的混合和传质,有望在提高脱硫剂的利用率方面实现突破。

KR process（also known as mechanical stirring method）has obvious advantages in the realization of deep desulphurization and stability of hot metal by compared with the injection process.However,due to the aggregation phenomenon of desulfurization flux during the stirring,there is a problem of low utilization ratio of lime desulfurization.The recent techniques for increasing the desulfurization efficiency the flux in hot metal by mechanical stirring were reviewed.Free CaO in desulfurization slag reacts with moisture or CO_2 in the air during cooling,causing CaO to expand and break into small particles.It is possible to reuse the slag by utilizing this phenomenon.But avoiding lime particle aggregation through flux addition method and the stirring dynamic improvement has more valuable than the slag recycling.In particular,according to the research results of chemical industry,the formation of the central vortex at the top of the stirring head is inhibited when two baffles are arranged symmetrically on the inner wall of a mechanicallystirred vessel,which results in the less aggregation of the particles,the better mixing and mass transfer between desulfurization flux and hot metal.It is expected that increasing the utilization ratio of the desulfurization flux achieves a breakthrough.