LF-RH工艺生产极低硫钢硫含量控制分析

Analysis on sulfur control in ultra low sulfur steel by LF-RH process

研究了LF炉渣脱氧剂加入量、LF动力学条件及RH后期钙处理对脱硫效果的影响。结果表明:向LF精炼渣中加入300 kg以上的铝粒时可以将渣中w(FeO+MnO)控制在0.5%以下,从而将钢液中w(S)由原来的30×10-6降至6×10-6;当底吹搅拌氩气流量为500 L/min,搅拌10 min后,钢液中w(S)可以降至6×10-6,过高或过低的吹氩流量都会影响脱硫效率;RH后期钙处理没有脱硫能力,但是钙线的加入有利于抑制回硫,并将硫含量保持在较低水平。

The present paper mainly studies how the LF slag deoxidizer, LF dynamics condition and the Ca-treatment affect the desulphurization after RH. The results show that the w（FeO＋MnO） can be controlled in below 0.5 % after adding more than 300 kg aluminum particles in the refining slag and w（S） in the steel is reduced from original 30×10-6to 630×10-6; and when the bottom gas flow rate is 500 L/min w（S） in the steel can be reduced to 6×10-6 after 10 min and too high or too low blow argon flow rate will affect the desulfurization efficiency. In this research later Ca-treatment in RH has no desulfurization ability, but addition of the calcium cladded wire can inhibit the sulfur pickup and keep the sulfur content in a low level.