转炉铁水预处理脱磷的基础理论分析

Theoretical Analysis of Hot Metal Dephosphorization Pretreatment in Converter

通过对转炉铁水预处理脱磷过程中选择性氧化的热力学和动力学分析,并结合首钢京唐公司300 t脱磷转炉的生产数据,研究熔池中铁、硅、锰、碳、磷的氧化过程,讨论影响磷在渣铁间分配比以及脱磷速率的主要因素.研究表明,将转炉铁水预处理温度控制在较低范围内(1300～1350℃),选择具有合适碱度(1.7～2.5)和成渣快的造渣工艺,并结合高的底吹搅拌强度(≥0.2 Nm^3/(t·min)),这是实现脱磷保碳、提高脱磷速率、加快生产节奏的有效途径.

Based on thermodynamic and dynamic calculation of hot metal dephosphorization in a converter, and the analysis of production data of a 300 t dephosphorization converter of Shougang Jingtang Steel Corporation, this paper studies the selective oxidation characteristics of Fe, Si, Mn, C, and P in a hot metal, and the main factors affecting dephosphorization. The phosphorus distribution between hot metal and slag are also discussed. The results show that Si and Mn are oxidized first during oxygen blowing when the oxygen potential increased, and oxidation of P and C occurs. To decrease the hot metal pretreatment temperature to about 1 300 - 1 350 °C and control the slag basicity to about 1.7 ~ 2.5 are the key to solving the problem of removing P at high carbon content. Improving the slagging dephosphorization converter combined with high bottom gas stirring intensity can dephosphorization rate. process in a improve the