Nickel slag, a byproduct come from the nickel flash smelting process, contains a high content of iron and different quantities of valuable metals, such as nickel, copper, cobalt, etc. It is a potential metal resource for the iron and steel industry. The reasonable development and utilization of nickel slag meets the requirements of comprehensive utilization of secondary resources, with environmental, economic, and social benefits. However, nickel slag is difficult to reduce because of its complex mineral composition and containing a lot of fayalite, so catalyzing the reduction of nickel slag to extract valuable metal has become an urgent issue. This work took the nickel slag with total iron content of 39.40wt% and SiO2 content of 32.50wt% as raw materials, the thermodynamic calculation and experimental were carried out with different proportions of sodium carbonate added. The results showed that with the increase of the proportion of sodium carbonate from 0 to 6wt%, the degree of metallization and iron recovery rate of the reduced products increased. The content of sodium carbonate increased to 8wt%, the degree of metallization and recovery rate of iron in the reduced products remained the same or even slightly decreased. The results of SEM showed that the particle size of iron in the reduction product without sodium carbonate added was only 6 μm, and EDS analysis showed that fayalite was abundant. However, the particle size of iron in the reduction product for nickel slag added with 6wt% sodium carbonate was 17 μm, and the content of fayalite was significantly decreased. The diffraction intensity of metallic iron was significantly increased in the XRD pattern. These results indicated that sodium carbonate can promote the reduction of nickel slag and the obtained large size of iron was helpful for subsequent magnetic separation.
Xiaoming LI Zhenyu WEN Yi LI Weian WANG Xiangdong XING
. Catalytic effect of sodium carbonate on the carbothermic reduction of nickel slag[J]. The Chinese Journal of Process Engineering, 2020
, 20(2)
: 182
-188
.
DOI: 10.12034/j.issn.1009-606X.219187
[1]张振强，崔雅茹，赵俊学，等.镍火法熔炼高钙低硅渣提取铁的研究[J].钢铁研究学报, 2013, 25(07):23-26 [2]矿产资源工业要求手册编委会.矿产资源工业要求手册 (2012年修订版) [M]. 地质出版社, 2012: 17. [3]Piatak N M, Parsons M B, Ii R R S.Characteristics and environmental aspects of slag: A review [J].Applied Geochemistry, 2014, 57(1):236-266 [4]Oh C J, Lee S O, Yang H S, et al.Selective leaching of valuable metals from waste printed circuit boards[J].Air Repair, 2003, 53(7):897-902 [5]Zhu D Q, Zhou X L, Luo Y H, et al.Reduction smelting low ferronickel from pre-concentrated nickel-iron ore of nickel laterite[J].High Temperature Materials & Processes, 2016, 35(10):1031-1036 [6]You Z X, Li G H, Wen P D, et al.Reduction of Sn-bearing iron concentrate with mixed H2CO gas for preparation of Sn-enriched direct reduced iron[J].Metallurgical and Materials Transactions B, 2017, 48(3):1486-1493 [7]陈伟鹏, 李光卫, 赵增武, 等.高铁煤泥作还原剂直接还原褐铁矿研究[J].矿冶工程, 2017, 37(01):68-72 [8]庞建明，郭培民，赵沛.铜渣低温还原与晶粒长大新技术 [J].有色金属(冶炼部分), 2013, 1(3):51-53-57 [9]赵志龙，唐惠庆，郭占成.气氛下、对金属铁析出微观形貌的影响[J].矿冶工程, 2012, 32(05):105-109 [10]Jiang T, Liu M D, Li G H, et al.Effects of sodium-salt on Al-Fe separation by reduction roasting for high-aluminum content limonite[J].Chinese Journal of Nonferrous Metals, 2010, 20(6):1226-1233 [11]鲁逢霖，郭玉华，张颖异, 等.镍渣直接还原磁选提铁试验[J].钢铁, 2014, 49(02):19-23 [12]Bai S J, Wen S M, Liu D W, et al.Beneficiation of high phosphorus limonite ore by sodium-carbonate-added carbothermic reduction[J].Isij International, 2012, 52(10):1757-1763 [13]Bai S J, Wen S M, Liu D W, et al.Catalyzing carbothermic reduction of siderite ore with high content of phosphorus by adding sodium carbonate[J].Isij International, 2011, 51(10):1601-1607 [14]丁闪，薛庆国，佘雪峰，等.碳酸钙对钒钛磁铁精矿直接还原-熔分的影响[J].钢铁, 2014, 49(8):15-20 [15]Basumallick A.Influence of CaO and Na2CO3 as additive on the reduction of hematite-lignite mixed pellets[J].Transactions of the Iron & Steel Institute of Japan, 2007, 35(9):1050-1053 [16]曹羽鑫，王恒辉，马江华，等.添加剂对铁精矿制备还原铁粉的影响[J].过程工程学报, 2018, 18(01):133-139 [17]Wang X D, Qu R T, Wu S J, et al.Notch fatigue behavior: metallic glass versus ultra-high strength steel[J].Scientific Reports, 2016, 6(1):355-357 [18]An X W, Wang J S, She X F, Ding Y G, et al.New technologies of energy saving and low CO2 emission for iron making [J]. Advanced Materials Research, 2012, 463-464: 957-961.[J].Advanced Materials Research, 2012, 463-464(1):957-961
