碱度对全钒钛球团矿性能的影响  

Effect of basicity on properties of all-vanadium titanomagnetite pellets

作　　者：胡鹏 吕学伟[2] 林文康 游志雄 令新科 HU Peng;LÜXuewei;LIN Wenkang;YOU Zhixiong;LING Xinke(Research Institute Co.,Ltd.,Pangang Group,Panzhihua 617000,Sichuan,China;College of Materials Science and Engineering,Chongqing University,Chongqing 400044,China;Xichang Steel Vanadium Co.,Ltd.,Pangang Group,Xichang 615000,Sichuan,China)

机构地区：[1]攀钢集团攀枝花钢铁研究院有限公司,四川攀枝花617000 [2]重庆大学材料科学与工程学院,重庆400044 [3]攀钢集团西昌钢钒有限公司,四川西昌615000

出　　处：《钢铁》2024年第11期45-53,共9页Iron and Steel

基　　金：国家重点研发计划资助项目(2018YFC1900501)。

摘　　要：通过配加石灰石进行了全钒钛球团矿造球和焙烧试验,并对生球强度、爆裂温度,预热和焙烧制度对球团强度和不同碱度条件下成品球团抗压强度、冶金性能和微观形貌进行了分析,研究碱度对全钒钛球团性能的影响规律。结果表明,碱度由0.11逐渐增大至1.10,生球落下强度先升高后降低、抗压强度先显著升高后逐渐稳定、爆裂温度逐渐降低,预热球团抗压强度逐渐降低,成品球团抗压强度先升高后逐渐降低,预热和焙烧温度对不同碱度条件下的全钒钛球团矿抗压强度影响较大,结合试验结果和现场生产实践,全钒钛球团矿适宜的碱度为0.5~0.7,预热温度为950℃,焙烧温度为1 250℃;随着球团矿碱度逐渐升高,中温还原度和还原膨胀指数逐渐升高,软化开始温度基本不变,软化结束温度逐渐降低,软化区间逐渐减小,滴落开始温度略微降低,软熔区间逐渐变窄,高温冶金性能逐渐改善;同时随着碱度增加,球团矿中硅酸盐、铁酸盐和钙钛矿等液相生成逐渐增多,在碱度小于0.7时液相起到了强化固结效果,且石灰石分解排出CO_(2)气体的同时增加了预热球的孔隙率,抑制了同心裂纹的形成,提高了抗压强度,但随着碱度进一步提高,液相增多后,阻碍了赤铁矿的固相固结并增加了细密孔洞形成,劣化了球团强度,导致球团矿抗压强度逐渐降低。The experiments of pelletizing and roasting of all-vanadium-titanium pellets was carried out by adding limestone,and the effect of green pellet strength,burst temperature,preheating and roasting system on pellet strength,compressive strength,metallurgical properties and micromorphology of finished pellets under different alkalinity conditions were analyzed.The results show that the basicity increases gradually from 0.11 to 1.1,the falling strength of vanadium titanium pellets increases first and then decreases,the compressive strength increases significantly first and then becomes stable,and the bursting temperature decreases gradually.The compressive strength of preheated pellets decreases gradually,and the compressive strength of finished pellets increases first and then decreases gradually.The preheating and roasting temperatures have a great influence on the compressive strength of vanadium titanium pellets with different alkalinity.Based on the experimental results and on-site production practice,the suitable alkalinity range of all-vanadium titanium pellets is 0.5-0.7 times,preheating temperature is 950℃,roasting temperature is 1250℃.As the alkalinity of pellets gradually increased,the reduction degree and reduction expansion index gradually increased,the softening beginning temperature remained basically unchanged,the softening end temperature gradually decreased,the softening interval gradually decreased,the dripping beginning temperature slightly decreased,the soft melting interval gradually narrowed,and the pyrometallurgical performance gradually improved.At the same time,with the increase of alkalinity,the liquid phase formation of silicate,ferrite and perovskite in the pellets gradually increases.When the alkalinity is less than 0.7,the liquid phase can strengthen the solid phase consolidation effect,and the decomposition of limestone and the discharge of CO_(2) gas can increase the porosity of the preheated pellets,inhibit the formation of concentric cracks,and improve the compressive strength.Th

关 键 词：碱度 全钒钛球团 抗压强度 预热制度 焙烧制度 冶金性能 物相 

分 类 号：TF046.6[冶金工程—冶金物理化学]