Study on improving the performance of vanadium-titanium magnetite oxidized pellets with limonite
-
摘要: 为了提高钒钛矿氧化球团抗压强度，通过相关球团试验，研究了配加褐铁矿对钒钛矿球团生球质量、成品球团强度、冶金性能和膨润土配比的影响，并通过对球团焙烧过程体积变化、物相组成等分析，阐述了褐铁矿提高钒钛矿氧化球团抗压强度的作用机理。研究结果表明，褐铁矿对强化钒钛矿生球和成品球团质量有显著的作用，随着褐铁矿配比的增加，生球抗压强度、落下次数和成品球抗压强度呈增加趋势，当褐铁矿配比为9%时，成品球团抗压强度为
3514 N/个。随着褐铁矿配比增加，T10（软化开始温度）、T40（软化终了温度）和软化区间减小，熔化区间增加，RSI变化不明显。随着褐铁矿替代膨润土比例增加，生球质量呈降低趋势，成品球团抗压强度先增大后减小，但均高于基准。配加适量的褐铁矿可以增加球团的低熔点相和孔隙率，磁铁矿氧化速率更快、氧化程度更均匀，球团孔隙分布更均匀且裂纹减少，成品球团抗压强度更高。Abstract: To improve the compressive strength of vanadium-titanium magnetite oxidized pellets, this study systematically investigated the effects of limonite addition on the quality of green pellets, compressive strength of fired pellets, metallurgical properties, and bentonite dosage ratio through comprehensive pelletizing experiments. The underlying mechanism of limonite in strengthening the compressive strength of vanadium-titanium magnetite oxidized pellets was elucidated through analysis of volume changes and phase composition during the roasting process. Experimental results demonstrate that limonite significantly enhances both green pellet and fired pellet quality. With increasing limonite content, the compressive strength of green pellets, drop resistance frequency, and compressive strength of fired pellets exhibited a progressive improvement. Notably, when the limonite addition reached 9%, the fired pellets achieved a compressive strength of3514 N/pellet. The study further revealed that increasing limonite content reduced T10, T40, and softening temperature range while expanding the melting temperature range, with the Reduction Swelling Index (RSI) remaining relatively stable. When substituting bentonite with limonite, green pellet quality showed a gradual decline, and the compressive strength of fired pellets initially increased before decreasing, though remaining consistently higher than baseline values. Appropriate limonite addition was found to enhance low-melting-point phases and porosity in pellets, promote faster and more uniform magnetite oxidation rate, optimize pore distribution with reduced cracks, and ultimately improve fired pellet strength. These findings provide critical insights for optimizing vanadium-titanium magnetite pellet production through strategic limonite utilization.-
Key words:
- vanadium-titanium magnetite /
- oxidized pellet /
- limonite /
- compressive strength /
- porosity
-
图 4 褐铁矿配比对钒钛磁铁矿生球质量的影响
Figure 4. Effect of limonite proportion on quality of green pellets of vanadium-titanium magnetite
图 5 褐铁矿配比对钒钛磁铁矿成品球团抗压强度的影响
Figure 5. Effect of limonite proportion on compressive strength of sintered pellets of vanadium-titanium magnetite
图 6 不同褐铁矿配比钒钛磁铁矿球团内部形貌
Figure 6. Internal morphology of vanadium-titanium magnetite pellets with different limonite proportions
（a）0；（b）9%；（c）98%
图 7 不同褐铁矿配比对钒钛磁铁矿球团熔滴性能的影响
Figure 7. Effect of different limonite proportions on melting and dripping properties of vanadium-titanium magnetite pellets
图 8 褐铁矿替代膨润土对球团生球质量的影响
Figure 8. Effect of limonite substitution for bentonite on green pellet quality
图 9 褐铁矿降低膨润土配比对成品球团抗压强度的影响
Figure 9. Effect of reducing bentonite proportion with limonite on compressive strength of sintered pellets
图 10 球团焙烧过程体积变化
（a）球团体积随温度的变化；（b）球团体积变化率随焙烧时间的变化
Figure 10. Volume change during pellet induration process
图 11 球团矿物相组成及孔隙度分析
Figure 11. Phase compositions and porosity analysis of pellets
物相组成：（a）JZ-BM,（b）LM-5,（c）JZ-LM；孔隙形貌：（d）JZ-BM,（e）LM-5,（f）JZ-LM
表 1 含铁原料主要化学成分和烧损
Table 1. Main chemical compositions and losses on ignition of iron-bearing materials
% Iron ore
concentrateTFe FeO SiO2 CaO MgO Al2O3 TiO2 V2O5 Ig VTM 57.03 33.45 2.76 0.45 3.03 3.31 10.05 0.71 -1.88 LM 30.75 <0.5 37.99 1.02 0.59 4.24 0.24 <0.1 7.24 
下载: 导出CSV
表 2 含铁原料粒度组成
Table 2. Size distribution of iron-bearing materials
% Iron ore
concentrate>0.074 mm 0.074~
0.047 mm0.047~
0.038 mm<0.038 mm <0.074 mm VTM 9.09 16.26 8.61 66.04 90.91 LM 12.14 20.62 6.68 60.56 87.86
下载: 导出CSV
表 3 含铁原料物理性能
Table 3. Physical properties of iron-bearing materials
Iron ore
concentrateSpecific surface
area /（cm2·g−1）True density /（g·cm−3） Maximum capillary
water capacity/%Maximum molecular
water capacity/%K VTM 1876 4.06 33.73 7.23 0.273 LM 2362 2.98 37.95 8.57 0.292
下载: 导出CSV
表 4 不同褐铁矿配比对钒钛磁铁矿球团熔滴性能和还原膨胀率的影响
Table 4. Effects of different limonite ratios on melting-dripping behavior and reduction swelling rate of vanadium-titanium magnetite pellets
Scheme T10/℃ T40/℃ T40-T10/℃ Ts/℃ Td/℃ Td-Ts /℃ ΔPmax/kPa H/mm RSI/% JZ 1161 1265 104 1299 1503 204 17.58 36.05 6.26 LM-3 1158 1248 90 1280 1488 208 22.33 36.54 6.77 LM-5 1145 1225 80 1259 1505 246 32.07 40.25 6.71
下载: 导出CSV
表 5 褐铁矿降低球团膨润土配比试验方案
Table 5. Experimental scheme for reducing bentonite proportion in pellets by adding limonite
% Scheme LM-3 LM-3-1 LM-3-2 LM-5 LM-5-1 LM-5-2 VTM 95 95 95 93 93 93 LM 3 4 5 5 6 7 BT 2 1 0 2 1 0
下载: 导出CSV
表 6 褐铁矿降低膨润土配比钒钛磁铁矿球团化学成分
Table 6. Chemical compositions of vanadium-titanium magnetite pellets with reduced bentonite proportion by adding limonite
% Scheme TFe FeO SiO2 CaO MgO Al2O3 TiO2 V2O5 JZ 55.37 0.515 3.57 0.37 2.90 3.36 10.02 0.708 LM-3 54.38 <0.5 4.85 0.33 3.06 3.58 9.61 0.682 LM-3-1 54.88 0.724 4.62 0.29 2.99 3.45 9.58 0.687 LM-3-2 55.00 <0.5 4.49 0.24 2.92 3.55 9.48 0.504 LM-5 54.25 0.643 5.52 0.37 3.01 3.56 9.40 0.668 LM-5-1 54.12 <0.5 5.40 0.32 2.94 3.49 9.69 0.678 LM-5-2 54.75 0.643 5.08 0.28 2.87 3.36 9.37 0.539
下载: 导出CSV
-
[1] GOU S Y. Discussing on increasing the utilization rate of titanium in Panzhihua mineral resources[J]. Iron Steel Vanadium Titanium, 2009, 30(3): 89-92. (苟淑云. 对提高攀枝花钛资源利用率的思考[J]. 钢铁钒钛, 2009, 30(3): 89-92.GOU S Y. Discussing on increasing the utilization rate of titanium in Panzhihua mineral resources[J]. Iron Steel Vanadium Titanium, 2009, 30（3）: 89-92. [2] WANG X D, JIN Y L. Strategy analysis and testing study of high ratio of pellet utilized in blast furnace[J]. Iron and Steel, 2021, 56(5) : 7-10. (王新东, 金永龙. 高炉使用高比例球团的战略思考与球团生产的试验研究[J]. 钢铁, 2021, 56 (5) : 7 - 16.WANG X D, JIN Y L. Strategy analysis and testing study of high ratio of pellet utilized in blast furnace[J]. Iron and Steel, 2021, 56(5) : 7-10. [3] FU W G, WEN Y C, XIE H E. Technologies and practices of BF intensified smelting of vanadium-bearing titanomagnetite at Pangang[J]. Iron Steel Vanadium Titanium, 2013, 34(3): 50-53. (付卫国, 文永才, 谢洪恩. 攀钢钒钛磁铁矿高炉强化冶炼技术与生产实践[J]. 钢铁钒钛, 2013, 34(3): 50-53.FU W G, WEN Y C, XIE H E. Technologies and practices of BF intensified smelting of vanadium-bearing titanomagnetite at Pangang[J]. Iron Steel Vanadium Titanium, 2013, 34（3）: 50-53. [4] HU P, JIANG S, TAN Y J, et al. Research and application of improving the compressive strength of full V-Ti pellets[J]. Iron Steel Vanadium Titanium, 2022, 43(4): 107-113. (胡鹏, 蒋胜, 谭阳杰, 等. 提高全钒钛球团矿抗压强度技术研究与应用[J]. 钢铁钒钛, 2022, 43(4): 107-113. doi: 10.7513/j.issn.1004-7638.2022.04.017HU P, JIANG S, TAN Y J, et al. Research and application of improving the compressive strength of full V-Ti pellets[J]. Iron Steel Vanadium Titanium, 2022, 43（4）: 107-113. doi: 10.7513/j.issn.1004-7638.2022.04.017 [5] MENG F Y, HUANG B F. Enhanced consolidation performance of vanadium-titanium magnetite oxide pellets[J]. Sintering and Pelletizing, 2020, 45(5): 49-53. (蒙飞宇, 黄帮福. 钒钛磁铁矿氧化球团固结性能强化研究[J]. 烧结球团, 2020, 45(5): 49-53. doi: 10.13403/j.sjqt.2020.05.069MENG F Y, HUANG B F. Enhanced consolidation performance of vanadium-titanium magnetite oxide pellets[J]. Sintering and Pelletizing, 2020, 45（5）: 49-53. doi: 10.13403/j.sjqt.2020.05.069 [6] GU B S, MA X X, ZHU Z K, et al. Oxidation kinetics of pellets prepared from iron concentrate with different specific surface areas[J]. The Chinese Journal of Process Engineering, 2023, 23(5): 755-762. (顾宝澍, 马叙叙, 朱子康, 等. 不同比表面积铁精矿球团氧化动力学[J]. 过程工程学报, 2023, 23(5): 755-762. doi: 10.12034/j.issn.1009-606X.222148GU B S, MA X X, ZHU Z K, et al. Oxidation kinetics of pellets prepared from iron concentrate with different specific surface areas[J]. The Chinese Journal of Process Engineering, 2023, 23（5）: 755-762. doi: 10.12034/j.issn.1009-606X.222148 [7] TANG W D, XUE X X, YANG S T, et al. Mineralogical characteristics and isothermal oxidation kinetics of Hongge chromium containing vanadium and titanium magnetite pellets[J]. Chinese Journal of Engineering, 2018, 40(5): 548-556. (汤卫东, 薛向欣, 杨松陶, 等. 红格含铬钒钛磁铁矿球团矿物学和等温氧化动力学[J]. 工程科学学报, 2018, 40(5): 548-556.TANG W D, XUE X X, YANG S T, et al. Mineralogical characteristics and isothermal oxidation kinetics of Hongge chromium containing vanadium and titanium magnetite pellets[J]. Chinese Journal of Engineering, 2018, 40（5）: 548-556. [8] CHEN S Y, CHU M S, TANG J, et al. Effects of pre oxidation on phase composition and microstructure of vanadium titano magnetite[J]. Journal of Northeastern University, 2013, 34 (4) : 536 - 540. (陈双印, 储满生, 唐珏, 等. 预氧化对钒钛磁铁矿球团矿相及内部结构的影响[J]. 东北大学学报 (自然科学版) , 2013, 34 (4) : 536 - 541.CHEN S Y, CHU M S, TANG J, et al. Effects of pre oxidation on phase composition and microstructure of vanadium titano magnetite[J]. Journal of Northeastern University, 2013, 34 (4) : 536 - 540. [9] LUO J, ZHENG K, HUANG Y, et al. Effect of oxygen volume fraction on the oxidation process of vanadium-titanium magnetite pellets[J]. Sintering and Pelletizing, 2024, 49(4): 49-56. (罗杰, 郑魁, 黄云, 等. 氧气体积分数对钒钛磁铁矿球团氧化过程的影响[J]. 烧结球团, 2024, 49(4): 49-56.LUO J, ZHENG K, HUANG Y, et al. Effect of oxygen volume fraction on the oxidation process of vanadium-titanium magnetite pellets[J]. Sintering and Pelletizing, 2024, 49（4）: 49-56. [10] ZUO W L. The influence of the oxidation process on the sintering and consolidation of titanium magnetite concentrate balls[J]. Iron and Steel, 1980(4): 72-73. (左文亮. 氧化过程对钛磁铁精矿球团焙烧固结的影响[J]. 钢铁, 1980(4): 72-73.ZUO W L. The influence of the oxidation process on the sintering and consolidation of titanium magnetite concentrate balls[J]. Iron and Steel, 1980（4）: 72-73. [11] CHEN X L, HUANG Y S, FAN X H, et al. Oxidation roasting behavior and concretion properties of vanadium-titanium magnetite pellet[J]. Journal of Central South University (Science and Technology), 2016, 47(2): 359-366. (陈许玲, 黄云松, 范晓慧, 等. 钒钛磁铁矿球团氧化焙烧行为和固结特性[J]. 中南大学学报 (自然科学版), 2016, 47(2): 359-366.CHEN X L, HUANG Y S, FAN X H, et al. Oxidation roasting behavior and concretion properties of vanadium-titanium magnetite pellet[J]. Journal of Central South University (Science and Technology), 2016, 47（2）: 359-366. [12] YU H B, PAN J, ZHU D Q, et al. Strengthening in processing and mechanism of magnetite with high MgO content pellet by high pressure grinding roller[J]. Journal of Central South University (Science and Technology), 2016, 47(5): 1465-1472. (于鸿宾, 潘建, 朱德庆, 等. 高压辊磨强化高镁磁铁矿球团工艺及机理[J]. 中南大学学报 (自然科学版), 2016, 47(5): 1465-1472.YU H B, PAN J, ZHU D Q, et al. Strengthening in processing and mechanism of magnetite with high MgO content pellet by high pressure grinding roller[J]. Journal of Central South University (Science and Technology), 2016, 47（5）: 1465-1472. [13] TANG M, CHO H J, PISTORIUS P C. Early gaseous oxygen enrichment to enhance magnetite pellet oxidation[J]. Metall Mater Trans B, 2014, 45: 1304-1314. doi: 10.1007/s11663-014-0064-5 [14] ERIKSSON A, ANDERSSON C, AHMED H, et al. Effect of varied oxygen levels on the oxidation of a magnetite pellet bed during pot furnace induration[J]. ISIJ International, 2021, 61(5): 1439-1449. doi: 10.2355/isijinternational.ISIJINT-2020-469 [15] GAO G F, ZHOU X L, SHI Z, et al. Study on roasting process of pure limonite pellet and its influencing factors[J]. Bulletin of the Chinese Ceramic Society, 2020, 39(2): 485-492. (高国锋, 周晓雷, 施哲, 等. 纯褐铁矿球团焙烧工艺及其影响因素研究[J]. 硅酸盐通报, 2020, 39(2): 485-492. doi: 10.16552/j.cnki.issn1001-1625.2020.02.018GAO G F, ZHOU X L, SHI Z, et al. Study on roasting process of pure limonite pellet and its influencing factors[J]. Bulletin of the Chinese Ceramic Society, 2020, 39（2）: 485-492. doi: 10.16552/j.cnki.issn1001-1625.2020.02.018 [16] LI Q, YANG Y B, JIANG T. Technology study of producing siderite and limonite pellets[J]. Mining and Metallurgical Engineering, 2009, 29(2): 59-62. (李骞, 杨永斌, 姜涛. 菱铁矿和褐铁矿球团制备技术研究[J]. 矿冶工程, 2009, 29(2): 59-62.LI Q, YANG Y B, JIANG T. Technology study of producing siderite and limonite pellets[J]. Mining and Metallurgical Engineering, 2009, 29（2）: 59-62. [17] CHEN H Y, WANG J C, GAO J D, et al. Effects of convert sludge on the shock temperature of green pellet[J]. Multipurpose Utilization of Mineral Resources, 2011, 32(3): 44-46. (陈慧艳, 王介超, 高景栋, 等. 转炉污泥对球团爆裂温度的影响[J]. 矿产综合利用, 2011, 32(3): 44-46.CHEN H Y, WANG J C, GAO J D, et al. Effects of convert sludge on the shock temperature of green pellet[J]. Multipurpose Utilization of Mineral Resources, 2011, 32（3）: 44-46. [18] QIU Y H, LUO G P, REN J, et al. Effect of iron-containing binder on oxidation kinetics of magnetite pellets[J]. China Metallurgy, 2024, 34(4): 39-48. (邱勇虎, 罗果萍, 任杰, 等. 含铁黏结剂对磁铁矿球团氧化动力学的影响[J]. 中国冶金, 2024, 34(4): 39-48. doi: 10.13228/j.boyuan.issn1006-9356.20230684QIU Y H, LUO G P, REN J, et al. Effect of iron-containing binder on oxidation kinetics of magnetite pellets[J]. China Metallurgy, 2024, 34（4）: 39-48. doi: 10.13228/j.boyuan.issn1006-9356.20230684 [19] ZHANG F M, XU W X, CHENG X F, et al. Analysis on key process and technology of blast furnace ironmaking on high charging proportion of pellet ore[J]. Iron and Steel, 2024, 59(3): 32-45. (张福明, 徐文轩, 程相锋, 等. 高炉高比例球团矿冶炼关键工艺技术分析[J]. 钢铁, 2024, 59(3): 32-45. doi: 10.13228/j.boyuan.issn0449-749x.20230381ZHANG F M, XU W X, CHENG X F, et al. Analysis on key process and technology of blast furnace ironmaking on high charging proportion of pellet ore[J]. Iron and Steel, 2024, 59（3）: 32-45. doi: 10.13228/j.boyuan.issn0449-749x.20230381 [20] LI W, FU G Q, CHU M S, et al. Phase transformation and non-isothermal oxidation kinetics of Hongge vanadium-bearing titanomagnetite[J]. Journal of Northeastern University Nature Science, 2017, 38(4): 517-521. (李尉, 付贵勤, 储满生, 等. 红格钒钛磁铁矿氧化物相转变及非等温氧化动力学[J]. 东北大学学报 (自然科学版), 2017, 38(4): 517-521. doi: 10.3969/j.issn.1005-3026.2017.04.013LI W, FU G Q, CHU M S, et al. Phase transformation and non-isothermal oxidation kinetics of Hongge vanadium-bearing titanomagnetite[J]. Journal of Northeastern University Nature Science, 2017, 38（4）: 517-521. doi: 10.3969/j.issn.1005-3026.2017.04.013 [21] GAN M, SUN Y F, FAN X H, et al. Preparing high-quality vanadium titano-magnetite pellets for large-scale blast furnaces as ironmaking burden[J]. Ironmaking & Steelmaking, 2020, 47(2): 130-137. doi: 10.1080/03019233.2018.1492500 [22] HAN T, XIAO S X, CHENG G J, et al. Preparation of vanadium titano-magnetite oxide pellets from western Liaoning province[J]. Multipurpose Utilization of Mineral Resources, 2023(3): 7-13. (韩通, 肖顺鑫, 程功金, 等. 辽西钒钛磁铁矿氧化球团制备实验[J]. 矿产综合利用, 2023(3): 7-13. doi: 10.3969/j.issn.1000-6532.2023.03.002HAN T, XIAO S X, CHENG G J, et al. Preparation of vanadium titano-magnetite oxide pellets from western Liaoning province[J]. Multipurpose Utilization of Mineral Resources, 2023（3）: 7-13. doi: 10.3969/j.issn.1000-6532.2023.03.002 -
计量
- 文章访问数: 1
- HTML全文浏览量: 0
- PDF下载量: 0
- 被引次数: 0
