微裂纹对硫化铜矿生物浸出的影响研究

利用紫金山低品位硫化铜矿,研究了微裂纹对铜生物浸出效果的影响。分别利用颚式破碎机、对辊破碎机和高压辊磨机对硫化铜矿进行破碎,采用体式显微镜、扫描电镜、核磁共振岩心成像系统和比表面积分析仪对矿石微裂纹及孔隙度进行观察统计与表征。结果表明,高压辊磨较颚式破碎和对辊破碎可以产生更多的微裂纹,同时高压辊磨破碎铜矿样品的孔隙度均高于颚式破碎和对辊破碎。-1.7mm粒级铜矿样品摇瓶浸出试验表明,由于高压辊磨破碎样品的比表面积和孔隙度更大,铜矿物与浸出液接触更加充分,浸出效果比颚式破碎和对辊破碎好。另外,-6.7+3.35mm粒级铜矿样品生物柱浸试验结果表明,含有更多微裂纹的高压辊磨破碎样品铜浸出率比颚式破碎提高9.10~15.43个百分点,比对辊破碎提高3.12~9.45个百分点。

Study on Influence of Microcracks on Bioleaching of Copper Sulfide

Effect of microcracks on copper bioleaching was studied with Zijinshan low-grade copper sulfide ore. Zijinshan low-grade copper sulfide ore was crushed by jaw crusher, roller crusher and high-pressure grinding roller (HPGR), respectively. Microcracks and porosity of ore were observed and tested by stereomicroscope, scanning electron microscope, nuclear magnetic resonance core imaging system and specific surface area analyzer, respectively. The results show that HPGR can produce more microcracks compared with jaw crusher and roller crusher, and porosity of copper ore samples crushed by HPGR is higher than that of other crushers. The results of shake flask bioleaching experiment of -1.7 mm copper ore sample show that copper leaching rate of samples crushed by HPGR is higher than that of other crushers due to larger specific surface area and porosity of samples crushed by HPGR, and contact between copper mineral and leaching solution is more sufficient. In addition, the results of column bioleaching experiment of -6.7+3.35 mm copper ore samples show that copper leaching rate of ores prepared by HPGR is 9.10-15.43 point percent higher than that of jaw crusher and 3.12~9.45 point percent higher than that of roller crusher.