富氧顶吹熔融还原全钛铁矿中杂质元素的行为研究

Research on the Behavior of Impurity Elements in the Oxygen-rich Topblowing Smelting Reduction Process of Ilmenite

采用富氧顶吹熔融还原炼铁技术冶炼全钛铁矿,研究了温度、碱度、配碳比对铁水磷含量、硫含量及碳含量的影响。试验结果表明:在碱度为1.3、配碳比为1.0、温度由1450℃提高到1600℃时,生铁中磷含量由0.015%提高到0.021%,硫含量由0.30%降低到0.24%,碳含量变化甚微;在温度为1550℃、配碳比为1.0、碱度由0.7提高到1.5时,磷含量由0.029%降低到0.017%,硫含量由0.32%降低到0.25%,碳含量呈现先降后升的趋势,在碱度为1.2时最低,为0.8%;在温度为1550℃、碱度为1.3,随着配碳比值由0.8升高到1.2时,磷含量由0.012%升高到0.018%,硫含量则由0.21%升高到0.31%。在富氧顶吹的强氧化性气氛下,生铁中硫含量高达0.30%左右,不满足炼钢铁水要求,所以炉外脱硫对于熔融还原铁水是必要的。

Adopting the iron-making process of oxygen-rich top-blowning smelting reduction from ilmenite, the effects of temperature, alkalinity and carbon fitting ratio on the phosphorus content, sulfur content and carbon content in molten iron were studied. The experimental results show that as temperature increases from 1450 ℃ to 1600 ℃, phosphorus content in the pig iron increases from 0. 015%to 0. 021%, sulfur content from 0.30% to 0. 24% and carbon content changes slightly under the conditions of basicity R of 1.3, carbon addition amount of 1.0. As basicity increases from 0.7 to 1.5, phosphorus content in the pig iron decreases from 0. 029% to 0. 017%, sulfur content from 0. 32% to 0. 25% and carbon content increases firstly, then decreases under the conditions of reduction temperature of 1550 ℃, carbon addition amount of 1.0. As carbon addition amount increases from 0. 8 to 1.2, phosphorus content in the pig iron increases from 0. 012% to 0. 018%, sulfur content from 0. 21% to 0.31% under the conditions of reduc- tion temperature of 1550 ℃, basicity R of 1.3. Sulfur content in pig iron is as high as about 0.30% for the powerful oxidization potential, which could not meet the quality of steelmaking. Therefore, it is necessary to carry out external desulfurization of pig iron.