环保型高磷铁水预脱磷渣的脱磷性能研究

实验室条件下采用间接测量法,测定了CaF2系和B2O3系脱磷渣的磷分配.即首先测量磷在液态渣和固态铁间的分配比,再通过计算得到磷在液态渣和铁水之间分配比,同时根据渣系成分和光学碱度计算了磷容量.同时采用了扫描电镜、能谱分析与X射线衍射分析技术对脱磷渣进行了研究.实验结果表明,B2O3系预脱磷渣的磷容量远大于CaF2系预脱磷渣的磷容量,因此可以用B2O3全部替代CaF2作为助熔剂进行高磷铁水的预脱磷处理,2种渣系的磷分配均随渣中有效CaO含量的升高而升高.用B2O3作为助熔剂时,B2O3能与渣中高熔点物质2CaO·SiO2和3CaO·P2O5反应生成低熔点物质,从而起到助熔的作用.且w(B2O3)/w(CaO)比值为0.16时,磷分配比为最高值,即该渣脱磷能力最强.

Study on dephosphorization performance of environment-friendly dephosphorization slag for high phosphorus hot metal pretreatment

Phosphorus distribution ratio of CaF2 system and B2O3 system dephosphorization slag for high phosphorus hot metal pretreatment were measured by an indirect measurement method under laboratory conditions. Firstly, phosphorus distribution ratio between slag in liquid state and solid iron was measured, then, phosphorus distribution ratio between liquid slag and hot metal was calculated. And phosphorus capacity was calculated according to composition and optical basicity of slag system. Dephosphorization slag was also studied by scanning electron microscopy, energy dispersive analysis and X- ray diffraction analysis. The experimental results show that phosphorus capacity of B2O3 system is much larger than CaF2 system??s. It is proved that B2O3 can replace completely CaF2 as fluxing agent for high phosphorus hot metal pretreatment. Phosphorus distribution ratios increase with increasing the effective content of CaO in two kinds of slag system. When B2O3 acts as fluxing agent, it can react with substances with high melting point such as 2CaO??SiO2 and 3CaO??P2O5 in slag to form new substances with low melting point. When the ratio of w(B2O3)/w(CaO) is 0. 16, phosphorus distribution ratio reaches maximum.Dephosphorization ability of this slag is the strongest.