碱性耐火材料的脱硫作用

Desulfurization of basic refractories

在不同CaO含量的碱性耐火材料坩埚中加入不同硫含量的铁粉 ,于 16 0 0℃保温不同时间 ,然后分析金属中残余硫含量。结果表明 :碱性耐火材料 ,特别是CaO有脱硫作用 ,2 0 %的CaO即可取得明显的脱硫效果 ;保温时间超过 30min后 ,出现“回硫”现象 ;

Iron powders with sulfur content of 0.08%,0.16% and 0.2% were put into crucibles made of basic refractories with CaO content of 20%,45%,55% and 60%, and then heated at 1600?℃ for 30?min, 45?min,75?min and 90 min respectively.After heating,the residual sulfur contents in the iron powders were analyzed.It was found that basic refractories,especially CaO can reduce the sulfur content in metals.The refractory with 20% CaO has considerable desulfurization effect for molten metals.When the soaking time at 1600?℃ was more than 30?min,“resulfurizing”was found in this study.The reason might be the transfer of FeO from slag and molten metal to the liquid in the refractory.The original S content of the metals gave a certain effects on desulfurization.