發(fā)布時(shí)間：2019-04-08 08:15

【摘要】：隨著近年來鋼鐵行業(yè)的急劇發(fā)展,粗鋼產(chǎn)量的不斷增長,2016年我國鐵礦石進(jìn)口量已達(dá)10.24億噸,但我國儲(chǔ)量巨大的高磷鐵礦資源依舊沒有得到大規(guī)模經(jīng)濟(jì)高效的開發(fā)利用。本文對內(nèi)配廢塑料高磷鐵礦含碳團(tuán)塊進(jìn)行直接還原-磁選研究,并研究了高磷鐵礦含碳團(tuán)塊的直接還原機(jī)理,為我國高磷鐵礦開發(fā)利用提供理論支撐。實(shí)驗(yàn)研究結(jié)果表明:在團(tuán)塊堿度0.8,添加4%硫酸鈉,焦粉用量16%的實(shí)驗(yàn)條件下,添加廢塑料替代25%焦粉(總含C量為13.19%)的團(tuán)塊在1150 ℃還原40 min,可得到金屬化率為88.77%的焙燒團(tuán)塊,還原后的團(tuán)塊在磨礦細(xì)度-0.074 mm占90%,磁選強(qiáng)度0.08 T的實(shí)驗(yàn)條件下,磁選可得到鐵品位為91.99%,金屬化率為92.26%的金屬鐵粉,鐵回收率可達(dá)86.74%�；鶞�(zhǔn)條件,添加4%硫酸鈉和添加4%硫酸鈉同時(shí)廢塑料替代25%焦粉三種條件下焙燒團(tuán)塊的微觀結(jié)構(gòu)研究結(jié)果表明:硫酸鈉可強(qiáng)化高磷鐵礦在直接還原過程中鐵晶粒的遷移,聚集長大,可以有效的使鐵得以富集;添加廢塑料替代25%焦粉后,直接還原過程中鐵晶粒遷移聚集效果良好。能譜分析結(jié)果表明,與基準(zhǔn)條件相比,添加硫酸鈉后金屬鐵晶粒中為純凈金屬Fe元素,添加4%硫酸鈉同時(shí)添加廢塑料替代25%焦粉后金屬鐵晶粒中出現(xiàn)少量P元素。在還原溫度1000 ℃-1150 ℃,還原時(shí)間40 min,N2/CO2為14/1的氣體條件下,基準(zhǔn)條件、添加4%硫酸鈉和添加4%硫酸鈉同時(shí)廢塑料替代25%焦粉三種條件下含碳團(tuán)塊還原動(dòng)力學(xué)表明,其還原的限制性環(huán)節(jié)均為氣體擴(kuò)散,還原反應(yīng)表觀活化能分別為240.92 kJ/mol、158.81kJ/mol和172.89 kJ/mol。加入硫酸鈉后,降低了表觀活化能,促進(jìn)了還原反應(yīng)的進(jìn)行,添加廢塑料替代25%焦粉后,表觀活化能有所升高,不利于還原反應(yīng)的進(jìn)行。
[Abstract]:With the rapid development of iron and steel industry in recent years and the continuous growth of crude steel output, China's iron ore import volume in 2016 has reached one billion twenty four million tons, but the huge reserves of high phosphorus iron ore resources in our country still have not been developed and utilized on a large scale economically and efficiently. In this paper, the direct reduction-magnetic separation of carbon-bearing pellets of waste plastic high-phosphorus iron ore is studied, and the direct reduction mechanism of carbon-bearing pellets of high-phosphorus iron ore is studied, which provides theoretical support for the development and utilization of high-phosphorus iron ore in China. The experimental results show that under the conditions of the basicity 0.8, the addition of 4% sodium sulfate and the amount of coke powder 16%, adding waste plastic instead of 25% coke powder (the total content of C is 13.19%) can be reduced to 40 min, at 1150 鈩，

本文編號：2454425