用钛渣电炉铁液生产Q10生铁的工艺研究

Process Investigation of Using Ti-slag Electric Furnace Iron Melt to Produce Q10 Pig Iron

针对钛渣电炉的铁液特点,采用25.5 MVA钛渣电炉和LF-ZTG 46铸铁机生产线试制了球墨铸铁用Q10生铁,其化学成分满足GB/T 1412—2005《球墨铸铁用生铁》标准的技术要求,气体含量较低,符合优质原铁液的气体含量要求。从渣系选择、底吹氩气、增碳、脱硫、脱钛五个主要方面进行了分析讨论,得出以下结论:(1)LF选用CaO-SiO2-CaF2渣系,碱度R控制在1.8~2.2,炉渣具有良好的流动性、脱硫和控铝能力;(2)底吹氩气搅拌,使铁液的温度和化学成分均匀,降低了铁液中的气体和夹杂物含量;(3)冶炼初期,向铁液加入2~4 kg/t的氧化铁皮脱钛,能使生铁的反球化作用指数K1≤0.91。

According to the iron melt characteristics of Ti slag electric furnace,the 25.5 MVA Ti-slag electric furnace and LF-ZTG-46 pig iron casting machine were used to conduct trial production of Q10 pig iron used for nodular iron production.Its chemical compositions met technical requirements of GB/T 1412—2005 pig iron for nodular iron,its gas content was relatively low and met the gas content requirement of high quality raw iron melt.The main aspects of slag system selection,bottom blowing Ar,C pick up,S removal,Ti removal were analyzed and discussed,following conclusions were obtained:(1)By selecting CaO-SiO2-CaF2 slag system,and controlling the alkalinity R at 1.8~2.2,the slag had good fluidity,S removal and Al control ability.(2)By bottom blowing Ar stirring,the temperature and chemical composition of the iron melt was uniform,and the content of gas and inclusions in the iron melt was reduced.(3)Adding 2~4 kg/t of iron oxide to the iron melt in the early stage of melting could make the anti-spheroidization index of pig iron K1≤0.91.