摘要
工业生产中,为生产出合格的钛渣必须加入适量的碳作为还原剂,将高价氧化物还原为低价氧化物。云南某公司30 MVA大型密闭直流电弧炉(DC炉)生产运行过程中,通过控制无烟煤用量与钛精矿用量之比——配碳比(ratio of anthracite to ilmenite,简称AIR),使生产在输入能量一定、钛精矿成分稳定的条件下力求获得良好的产品品质。生产通过中空石墨电极将钛精矿和无烟煤加入DC炉内,熔炼温度控制为1973～2023 K;熔炼输入功率为15 MVA;入炉钛精矿粒度为0.1～0.33 mm;入炉无烟煤粒径为5～25 mm的比例大于85%。理论上熔炼还原1 t钛精矿,将会产出526 kg渣和368 kg金属铁,O/I比率约为89.4%,理论配碳比约为7.895%。通过生产物料衡算得出,一定熔炼周期内的AIR平均值为12.228%,O/I比率平均值为81.317%。在配碳量不足的情况下,钛精矿中的FeO易于离解出氧并与碳结合,使FeO还原反应优先于TiO2等氧化物,碳最大可能的消耗在FeO的还原上;配碳量越高,则碳将用于还原难还原的氧化物(如MgO,CaO,MnO等)上,使FeO的还原受到抑制。配碳比还会影响DC电炉熔渣流动性和挂渣层。试生产熔炼周期内,通过调整AIR,实现了钛渣中TiO2品质的提高,其含量可从82%提高到89%以上。
The adequate carbon should be fed as reductant in order to achieve qualified titanium slag,and deoxidized the highoxide to lowoxide.The domestic first 30 MVA DC arc furnace of a company in Yunnan province obtained the favorable slag by controlling the ratio of anthracite to ilmenite（AIR）,in the case of certain energy input and stable component of ilmenite.The ilmenite and anthracite were put into DC furnace through hollow graphite electrode,meanwhile it was needed to control temperature between 1973 K and 2023 K,15 MVA of input power,0.1~0.33 mm of partical size of ilmenite,the ratio of anthracite partical size range of 5~25 mm were more than 85%.Theoretically,deoxidizing 1t ilmenite would produce 526 kg titanium slag and 368 kg iron,and Output/Input rate was about 89.4%,the theory AIR was about 7.895%.Calculated on mass balance,the mean AIR during the smelting period was 12.228%,and output/input rate was 81.317%.With the short of anthracite,the oxygen of FeO in ilmenite would be easy to dissociate and combine with carbon;in this case,the reduction reaction of FeO would be prior to TiO2.On the other hand,with more carbon,the carbon will be used for deoxidizing the oxide that are difficult to reducte,for example,MgO,CaO,MnO and so on,and the reduction of FeO would be restrained.AIR also effects on the fluidity of molten slag and freeze lining.The content of TiO2 in the titanium slag increased to more than 89% from 82% in the trial by modulating the AIR.
出处
《稀有金属》
EI
CAS
CSCD
北大核心
2012年第2期297-303,共7页
Chinese Journal of Rare Metals
基金
国家科技部国际合作资助项目(2007DFA71490)
关键词
直流电弧炉
钛铁矿
钛渣
碳还原
配碳比
direct current electric arc furnace
ilmenite
titanium slag
carbon reduction
ratio of anthracite to ilmenite
