磷在脱磷渣中2CaO·SiO2固相颗粒内的扩散速率

中国铁矿磷含量偏高,提高脱磷效率、降低渣料的消耗量对钢铁企业至关重要.1 400℃下,将2CaO·SiO2颗粒插入到含P2 O5为14％(质量分数)的渣中,并保温20、30、60和100 s,研究磷在2CaO· SiO2颗粒中的扩散速率.用SEM-EDS对磷在渣和2CaO·SiO颗粒中的分布进行了测量,并用菲克第二定律计算了磷在2CaO·SiO颗粒中的扩散系数.结果显示:磷在2CaO·SiO中的扩散可视为一维半无限扩散.1 400℃时,磷在2CaO· SiO2颗粒中的扩散系数为6.417×10-12 m2/s,如果脱磷时间为15～20 min,则2CaO· SiO2颗粒不宜大于653 μm.

Phosphorus diffusion rate in 2CaO · SiO2 solid particle in dephosphorization slag

Due to high phosphorus content of Chinese iron ore, improving the efficiency of dephosphorization and reducing consumption of slag are important for steelmakers. The 2CaO??SiO2 particles were inserted into the slag with 14 mass% P2O5 and held for 10??30??60 and 100s to study phosphorus diffusion rate in 2CaO??SiO2 solid particle at 1400??. The distribution of phosphorus in the slag and 2CaO??SiO2 solid particle was measured by SEM-EDS. The phosphorus diffusion coefficient in 2CaO??SiO2 solid particle was calculated with Fick??s second law. The experimental results show that phosphorus diffusion in 2CaO??SiO2 particles can be regarded as one-dimensional infinite diffusion. The phosphorus diffusion coefficient is 6??417??10-12 m2/s at 1400??. If the dephosphorization time is less than 20min, the 2CaO??SiO2 particle size should be smaller than 653??m.