地质聚合反应制团对低品位铜矿石高压辊破碎——生物浸出的影响

为使团聚体在酸性条件下保持稳定并提高浸出效率,对高压辊磨机破碎后的低品位铜矿石进行了地质聚合反应制团后的生物浸出研究。考察了地质聚合物凝胶对浸矿微生物氧化活性的影响,以及原料、团聚体和粗颗粒矿石在柱浸中的表现,并借助核磁共振波谱(NMR)和扫描电子显微镜(SEM)分析技术研究了团聚体的性质。结果表明:经高压辊磨机破碎的矿石制团后浸出,66 d浸出率为61%,而粗颗粒矿石在相同时间内浸出率仅为28%;地质聚合物凝胶不会减弱微生物的氧化活性;原料经制团后渗透性显著提高且团聚体在柱浸时能长时间保持稳定;地质聚合物凝胶的形成是团聚体在酸性条件下稳定的原因,且矿石颗粒以地质聚合反应团聚后,颗粒间仍存在有大量的孔隙和裂纹而利于浸出。高压辊磨机破碎后的低品位铜矿石经地质聚合反应制团后生物浸出可使得低品位铜矿石的提取更加高效,并被期望在堆浸中得到应用。

Effect of Agglomeration through Geopolymerization on the Bioleaching of Low-Grade Copper Ore from High Pressure Grinding Roll

In order to keep agglomerates stable under acidic conditions and improve leaching efficiency， the bioleaching of low-grade copper ore from high pressure grinding roll after agglomeration through geopolymerization was studied. The effects of geopolymer gel on the oxidation activity of microorganisms and the performances of raw materials， agglomerates and coarse-grained ores in column leaching were investigated. The properties of agglomerates were studied by means of Nuclear Magnetic Resonance （NMR） and Scanning Electron Microscope （SEM）. The results showed that the ore from the high pressure grinding roll were leached after agglomeration， and the leaching rate was 61% after 66 days， while the leaching rate of coarse-grained ores in the same time was only 28%. The geopolymer gel did not weaken the oxidation activity of the microorganisms. The permeability of raw materials was significantly improved after agglomeration， and the agglomerates could remain stable for a long time during column leaching. The formation of geopolymer gel was the reason for the stability of agglomerates under acidic conditions. After the ore particles were agglomerated through geopolymerization， there were still a large number of pores and cracks between the particles， which was beneficial for leaching. The bioleaching of low-grade copper ore from high pressure grinding roll after agglomeration through geopolymerization can make the extraction of low-grade copper ore more efficient， which is expected to be applied in the heap leaching.