侧吹熔炼处置锌冶炼渣炉渣组成对导热性及析出物相的影响

Influence of Slag Composition on Thermal Conductivity and Precipitated Phase Structure of Zinc Smelting Slag Treated by Side-Blown Smelting

侧吹熔炼炉采用水冷挂渣炉壁时,高导热系数炉渣可在炉衬表面形成稳定渣皮,保护并延长炉衬的使用寿命。针对铁矾渣和铅银渣处理用FeO-CaO-SiO_(2)-PbO-ZnO五元渣系,采用稳态平板法对炉渣渣皮的导热系数进行了测定,并通过扫描电镜对固态渣皮进行微观结构分析,以探究炉渣组分改变对渣皮导热系数及结晶矿相的影响。结果表明,增加CaO和SiO_(2)都会使渣皮导热系数增大,其中添加CaO对渣型影响最显著。优化渣型的导热系数从原渣的7.62 W/(m·K)增大到了17.94 W/(m·K),提高了135%。在冷凝过程中,高温析出的物相为黄长石,其熔点、黏度相较于原渣也有显著降低。调整后的渣型更容易形成稳定的渣皮,有利于水冷挂渣护炉。

When the side-blown smelting furnace adopts water-cooled slag-hanging furnace wall,the slag with high thermal conductivity can form a stable slag shell on the surface of the furnace lining to protect and prolong the service life of the furnace lining.Aiming at FeO-CaO-SiO_2-PbO-ZnO five-element slag system used for treating jarosite residue and lead-silver slag,the thermal conductivity of furnace slag crust was measured by steady-state plate method,and the microstructure of solid slag crust was analyzed by SEM to explore the influence of slag composition change on thermal conductivity and crystalline mineral phase of slag crust.The results show that adding CaO and SiO_(2) will increase the thermal conductivity of slag crust,especially the addition of CaO has the most significant effect on slag type.The thermal conductivity of the optimized slag type rises to 17.94 W/(m·K),which is 135% higher than that of the original slag.The phase precipitated at high temperature during the condensation process is melilite,and its melting point and viscosity are significantly lower than that of the original slag.The adjusted slag type is easier to form a stable slag crust,which is beneficial to water cooling and slag hanging to protect the furnace.