DIFFERENCE OF IRON REMOVAL EFFICIENCIES FROM CIRCULATING FLUIDIZED BED FLY ASH AND PULVERIZED COAL FLY ASH BY MAGNETIC SEPARATION
-
摘要: 粉煤灰中氧化铁是其高值化利用过程的主要杂质,高效去除铁杂质对于粉煤灰高值利用具有重要意义。采用湿法磁选方法对循环流化床粉煤灰(CFB灰)、碳热还原循环流化床粉煤灰(R-CFB灰)及煤粉炉粉煤灰(PC灰)进行除铁研究,并对不同类型粉煤灰中铁的存在形式进行对比,最后对粉煤灰中铁的去除和铝的回收进行了考察。结果表明:CFB灰直接磁选铁的去除率仅为17.6%,PC灰直接磁选铁的去除率可达到55.8%,这与CFB中的铁主要以赤铁矿形式存在,而PC灰中的铁主要以磁铁矿形式存在有关;经碳热还原后CFB灰中的铁由赤铁矿转变为磁铁矿,在磁场强度为400 mT,磁选3次,液固比为20:1的条件下,R-CFB灰的除铁率为64.7%,,铁含量从3.4%降低到1.2%,且铝的回收率为78.6%。与PC灰磁选法除铁效果对比,经碳热还原的CFB灰可达到较高的除铁率。Abstract: Iron oxide in fly ash is the main impurity for its high value utilization process. Efficient removal of iron impurities is of great significance for the high value utilization of fly ash. In this paper, the wet magnetic separation method was used to remove iron from circulating fluidized bed fly ash (CFB ash), carbonthermal reduction circulating fluidized bed fly ash (R-CFB ash) and pulverized coal furnace fly ash (PC ash). Research and comparison of the existence forms of iron in different types of fly ash were studied and compared, and finally the removal of iron and recovery of aluminum in fly ash were examined. The results showed that the iron removal efficiency of CFB ash using direct magnetic separation method was only 17.6%, and the iron removal efficiency of PC ash using direct magnetic separation method could reach 55.8%. The iron in CFB mainly existed in the form of hematite, while iron was mainly related to the existence of magnetite in PC ash. The hematite in CFB ash was converted to magnetite after carbonthermal reduction, and the iron removal of R-CFB ash was 64.7%, with a magnetic field strength of 400 mT, magnetic separation 3 times and liquid-solid ratio of 20:1. The iron content was reduced from 3.4% to 1.2%, and the recovery of aluminum was 78.6%. Compared with the iron removal of PC ash, the carbonthermal reduction CFB ash could achieve higher iron removal efficiency.
-
Key words:
- circulating fluidized bed fly ash /
- pulverized coal fly ash /
- magnetic separation /
- hematite /
- magnetite
-
LI J, ZHUANG X G, LEIVA C, et al. Potential utilization of FGD gypsum and fly ash from a Chinese power plant for manufacturing fire-resistant panels[J]. Construction and Building Materials, 2015, 95:910-921. FARWA M, MUHAMMAD Z, IJAZ A B, et al. Possible applications of coal fly ash in wastewater treatment[J]. Journal of Environmental Management, 2019, 240:27-46. YAO Z T, XIA M S, SARKER P K, et al. A review of the alumina recovery from coal fly ash, with a focus in China[J]. Fuel, 2014, 120:74-85. DING J, MA S H, SHEN S, et al. Research and industrialization progress of recovering alumina from fly ash:a concise review[J]. Waste Management, 2016,60:375-387. 李超, 王丽萍, 郭昭华,等. 粉煤灰中锂提取技术研究进展[J]. 有色金属(冶炼部分), 2018(4):46-50. 王凯,孙菱翎,邱广明,等. 粉煤灰基沸石的制备及对橙黄G吸附性能研究[J]. 功能材料, 2019, 50(2):2133-2138. 熊林. 粉煤灰基多孔陶瓷材料的研制[D]. 长沙:中南大学, 2008. 刘自亮. 粉煤灰制备铝硅合金过程中预处理除铁工艺研究[D]. 昆明:昆明理工大学, 2016. 李素平. Fe2O3和TiO2等杂质在矾土基Sialon转型过程中的变化及作用[D]. 郑州:郑州大学, 2004. SEIDEL A, ZIMMELS Y. Mechanism and kinetics of aluminum and iron leaching from coal fly ash by sulfuric acid[J]. Chemical Engineering Science, 1998, 53(22):3835-3852. 郭强. 粉煤灰酸法提取氧化铝的工艺研究进展[J]. 洁净煤技术, 2015, 21(5):115-118,122. MOLINA A, POOLE C. A comparative study using two methods to produce zeolites from fly ash[J]. Minerals Engineering, 2004, 17(2):167-173. WANG M H, ZHAO H, LIU Y, et al. Removal of Fe from fly ash by carbon thermal reduction[J]. Microporous and Mesoporous Materials, 2017, 245:133-137. 孙少博, 张永锋, 崔景东,等. 粉煤灰高值化利用中的除铁工艺[J]. 化工新型材料, 2015,43(1):223-225. KUTCHKO B G, KIM A G. Fly ash characterization by SEM-EDS[J]. Fuel, 2006, 85(17/18):2537-2544. 王恩. 煤粉炉粉煤灰与循环流化床粉煤灰矿物学性质比较[J]. 洁净煤技术, 2016, 22(4):26-29. 刘芳, 顾国维, 韩作振. 锅炉类型与粉煤灰的物相特征[J]. 同济大学学报(自然科学版), 2003, 31(8):990-994. VASSILEV S V, MENENDEZ R, ALVAREZ D, et al. Phase-mineral and chemical composition of coal fly ashes as a basis for their multicomponent utilization. 1. Characterization of feed coals and fly ashes[J]. Fuel, 2003, 82(14):1793-1811. WANG T, YANG H R, WU Y X, et al. Experimental study on the effects of chemical and mineral components on the attrition characteristics of coal ashes for fluidized bed boilers[J]. Energy & Fuels, 2012, 26(2):990-994. 裴亚利. 循环流化床粉煤灰的特征及其综合利用研究[D]. 长春:吉林大学, 2006. 李解, 李保卫, 张邦文. Fe2O3转变为Fe3O4粉末的微波碳热还原[J]. 北京科技大学学报, 2011, 33(9):1127-1132. UWADIALE G G O O, WHEWELL R J. Effect of temperature on magnetizing reduction of agbaja iron ore[J]. Metallurgical Transactions B, 1988, 19(5):731-735. MENDRELA E, OSADNIK Z, STASZAK J, et al. High capacity magnetic separator for volatile dust[J]. IEEE Transactions on Magnetics, 1983, 19(3):1476-1479. 宫振宇, 王明华, 王凤栾,等. 磁选法去除粉煤灰中磁性铁的研究[J]. 材料与冶金学报, 2011, 10(4):257-259. 期刊类型引用(22)
1. 胡继娟,王小治,侯建华. 碳基材料负载纳米零价铁对铬废水的处理研究进展. 现代化工. 2025(02): 63-67 . 百度学术
2. 蒋君丽,张蕾. 有机修复剂在化工污染场地土壤修复中的应用研究. 皮革制作与环保科技. 2025(01): 124-126 . 百度学术
3. 赵文媛,王春勇,李英,田沙沙. 纳米零价铁对化工污染土壤修复研究现状. 辽宁化工. 2024(01): 103-105 . 百度学术
4. 李杉杉,张荣,费杨,梁家辉,杨兵,王萌,师华定,陈世宝. Fe对稻田土壤重金属迁移转化影响机制及研究进展. 地学前缘. 2024(02): 103-110 . 百度学术
5. 辛世纪,易校石,王江涛,祁宝川. 红柳生物炭负载纳米零价铁对Cr(Ⅵ)的吸附特性及机理. 伊犁师范大学学报(自然科学版). 2024(01): 45-54 . 百度学术
6. 徐玥,徐学敏,时悦,赵晨浩,王圣森. 基于茶渣的生物炭负载零价铁对水体和土壤中Cr(Ⅵ)的修复及机理研究. 环境污染与防治. 2024(05): 638-644 . 百度学术
7. 郭伟. 纳米零价铁修复污染土壤技术研究进展. 青海环境. 2024(03): 169-172 . 百度学术
8. 钟鑫莲,王梦璐,季宏兵. 铁基生物炭复合材料修复重金属污染的研究进展. 化工新型材料. 2024(10): 61-65 . 百度学术
9. 曾涛涛,农海杜,沙海超,陈胜兵,张晓玲,刘金香. 污泥基生物炭负载纳米零价铁去除Cr(Ⅵ)的性能与机制. 复合材料学报. 2023(02): 1037-1049 . 百度学术
10. 祁宝川,徐志亮,易校石,徐虎,冯丹. 生物炭负载纳米零价铁的制备及其在环境修复中的研究进展. 化学通报. 2023(07): 815-823 . 百度学术
11. 王阳,高衍浩,孔凡今. 生物炭负载纳米零价铁修复重金属污染土壤的研究进展. 山东化工. 2023(10): 98-101 . 百度学术
12. 徐曼云,韩超,江鉴廷,时红,丁园. 炭基质钝化剂对土壤Cd、Cu的阻控效果与老化机制. 南昌航空大学学报(自然科学版). 2023(03): 88-94 . 百度学术
13. 熊子璇,杨卫春,贺宇宏,李琦,廖骐,杨志辉,司梦莹. 氧化条件下铁基材料还原Cr(Ⅵ)产物稳定性研究. 有色冶金设计与研究. 2023(06): 38-45 . 百度学术
14. 李靖,钟为章,宁志芳,牛建瑞,韩永辉,马彩云. 改性生物炭强化土霉素菌渣厌氧消化研究. 环境科学与技术. 2023(12): 109-116 . 百度学术
15. 姜维,杨芳俐,吴永红,陈冠忠,陈红凤,唐次来. Fe~0/Fe_3O_4复合材料同时去除水中多种重金属的效果. 环境工程学报. 2022(04): 1186-1198 . 百度学术
16. 李也. 铁基稳定化材料在重金属污染土壤修复中的应用. 广东化工. 2022(10): 119-121+155 . 百度学术
17. 徐皓普,汤波. 改性生物炭在土壤重金属修复中的机理及应用. 化工技术与开发. 2022(09): 49-53 . 百度学术
18. 刘诗婷,刘静,刘爱荣,张伟贤. 纳米零价铁基材料用于地下水修复研究进展. 环境科学与技术. 2022(09): 181-193 . 百度学术
19. 陈龙,李启婷,钱坤鹏. 重金属铬污染土壤的修复技术研究进展. 应用化工. 2022(10): 3058-3062 . 百度学术
20. 刘菁,田一梅,刘云慧,褚献献,刘然,单金林. pH值、硫酸根和温度对钢管管垢中铬释放的影响. 中国环境科学. 2022(12): 5679-5686 . 百度学术
21. 祝世文,程涛,屈刘盼盼,倪兵. 铜污染土壤修复技术及其应用研究进展. 湖北理工学院学报. 2021(01): 22-26 . 百度学术
22. 梁佳怡,王泳森,段敏,李艺,陈喆,于方明,刘可慧. 生物质炭对土壤有效态镉及植物镉吸收影响的整合分析. 广西师范大学学报(自然科学版). 2021(06): 1-12 . 百度学术
其他类型引用(17)
-

计量
- 文章访问数: 198
- HTML全文浏览量: 30
- PDF下载量: 2
- 被引次数: 39