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 CO₂ 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 mechanically-stirred 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.