摘要
对某低品位硅镁型红土镍矿(镍和铁质量分数分别为0.82%和9.67%)在甲烷气氛下进行还原焙烧-磁选试验。利用气相色谱仪,验证了甲烷在实际还原过程中被裂解成了氢气和炭黑。热力学计算表明:试验温度为873~1 173 K时,氧化镍分别与H_2、C、CO反应,均被还原为金属镍。氧化铁与C、CO发生反应,均被还原为金属铁,而氧化铁与H_2发生反应,产物为氧化亚铁。MgSiO_3与Mg_2SiO_4相比,更容易与硫酸钠(Na_2SO_4)发生反应。研究了还原温度、还原时间和添加剂用量对红土镍矿还原焙烧的影响,综合考虑镍、铁品位和回收率,确定了最优试验条件:还原温度为800℃,还原时间为90 min,添加剂Na_2SO_4质量分数为20%。
A low-grade garnierite laterite ore composed of 0. 82% Ni and 9. 67% Fe was studied through roasting-magnetic process under the condition of methane atmosphere. The methane was proved to be decomposed to carbon and hydrogen by gas chromatograph. Thermodynamic calculations show that nickel oxides is reduced to metallic nickel by H_2,C,CO at 873 K to 1 173 K. Iron oxides is reduced to metallic iron by C and CO,but iron oxide is reduced to ferrous oxide by H_2. MgSiO_3 is more likely to react with sodium sulfat than Mg_2SiO_4. The effects of reduction temperature,reduction time and additive dosage on the laterite ore in the reduction roasting process were studied. In comprehensive consideration of the grade and recoveries of nickel and iron,the optimum conditions for reduction process are that reduction temperature is 800 ℃,reduction time is 90 min,the mass fraction of additive sodium sulfate is 20%.
出处
《河南科技大学学报(自然科学版)》
CAS
北大核心
2018年第3期99-104,共6页
Journal of Henan University of Science And Technology:Natural Science
基金
国家自然科学基金项目(U1302274
51304091)
关键词
热力学
红土镍矿
甲烷
硫酸钠
thermodynamics
lateritic nickel ore
methane
sal mirabile