Fragmentation mechanism of low-grade hematite ore in a high pressure grinding roll  

作　　者：袁致涛 李丽匣 韩跃新 刘磊 刘廷 

机构地区：[1]School of Resources and Civil Engineering,Northeastern University [2]Zhenzhou Institute of Multipurpose Utilization of Mineral Resources,Chinese Academy of Geological Sciences (CGS)

出　　处：《Journal of Central South University》2016年第11期2838-2844,共7页中南大学学报（英文版）

基　　金：Project(2012AA062301)supported by the National High Technology Research and Development Program of China

摘　　要：The fragmentation mechanism of low-grade hematite ore in a high pressure grinding roll(HPGR) was studied based on the characteristics of comminuted products at different specific pressure levels. The major properties included the reduction ratio, liberation, specific surface energy, and specific surface area. The results showed that the fracture of low-grade hematite ore in HPGR was an interactive dynamic process in which the interaction between coarse particles of gangue minerals and fine particles of valuable minerals was alternately continuous with increased compactness and compacting strength of materials. Within a range of 2.8–4.4 N/mm^2, valuable minerals were crushed after preferentially absorbing energy, whereas gangue minerals were not completely crushed and only acted as an energy transfer medium. Within a range of 4.4–5.2 N/mm^2, gangue minerals were adequately crushed after absorbing the remaining energy, whereas preferentially crushed valuable minerals acted as an energy transfer medium. Within a range of 5.2–6.0 N/mm^2 range, the low-grade hematite ore was not further comminuted because of the "size effect" on the strength of materials, and the comminution effect of materials became stable.The fragmentation mechanism of low-grade hematite ore in a high pressure grinding roll（HPGR） was studied based on the characteristics of comminuted products at different specific pressure levels. The major properties included the reduction ratio, liberation, specific surface energy, and specific surface area. The results showed that the fracture of low-grade hematite ore in HPGR was an interactive dynamic process in which the interaction between coarse particles of gangue minerals and fine particles of valuable minerals was alternately continuous with increased compactness and compacting strength of materials. Within a range of 2.8–4.4 N/mm^2, valuable minerals were crushed after preferentially absorbing energy, whereas gangue minerals were not completely crushed and only acted as an energy transfer medium. Within a range of 4.4–5.2 N/mm^2, gangue minerals were adequately crushed after absorbing the remaining energy, whereas preferentially crushed valuable minerals acted as an energy transfer medium. Within a range of 5.2–6.0 N/mm^2 range, the low-grade hematite ore was not further comminuted because of the ＂size effect＂ on the strength of materials, and the comminution effect of materials became stable.

关 键 词：high pressure grinding roll HEMATITE specific pressure fragmentation mechanism 

分 类 号：TD921.4[矿业工程—选矿] TD453