柱式反应器中粒径对低品位镍矿生物浸出的影响

Effect of particle size on bioleaching of low-grade nickel ore in a column reactor

本文研究了生物柱浸出低品位镍矿中镍的浸出,并考察了不同粒度对浸出镍的影响。将镍矿石(平均镍含量为0.23%)破碎成>10 mm,5~10 mm,2~5 mm和<2 mm四种不同粒径的颗粒度。属水平上菌株的主要成分为硫杆菌属53.11%、钩端螺旋菌属43.52%和嗜酸菌属3.37%。浸出试验条件控制在pH 2.0和23℃。经过180 d的生物浸出实验,>10 mm(生物浸出),5~10 mm(酸浸出),5~10 mm(生物浸出),2~5 mm(生物浸出)的镍浸出率分别为23.76%,22.15%,32.42%和54.17%。分析粒度为2~5 mm的矿石,浸出前后矿石粒度发生很大变化,其中2~5 mm粒度的矿石比例降到44.64%。实验结果表明,柱式生物浸出最适合2~5 mm粒径的矿石,适当控制矿石粒度可以实现镍的高效浸出,可以为企业提供参考数据。

Biological column leaching of Ni from low-grade Ni ore was studied,and the effects of ore particle size on leaching rate were investigated.The Ni ore with an average Ni content of 0.23%was crushed into four different particle size fractions:>10 mm,5−10 mm,2−5 mm and<2 mm.The main strain components at the genus level were acidithiobacillus(53.11%),leptospirillum(43.52%),and acidiphilium(3.37%).The leaching tests were carried out at pH 2.0 and~23℃.The Ni leaching rates from ores with particle sizes>10 mm(bioleaching),5–10 mm(acid leaching),5–10 mm(bioleaching),and 2–5 mm(bioleaching)were 23.76%,22.15%,32.42%and 54.17%,respectively,after 180 d of bioleaching.The ore particle size changed after leaching,compared with the original ore size,the proportion of the same size of 2−5 mm ore decreased to 44.64%.Ore with particle size of 2–5 mm was most suitable for column bioleaching,and effective Ni extraction was achieved with appropriate control of ore granularity.