鞍山式赤铁矿石球磨磨矿动力学研究

Grinding Kinetics of Anshan Type Hematite Ores in a Ball Mill

应用MATLAB软件对鞍山式赤铁矿磨矿瞬时速度进行研究.矿料在球磨过程中经历＂粗粒级快速碎磨-中粒级动态碎磨-中粒级单一碎磨＂三个固有阶段.0.043-0.031 mm粒级比0.105-0.043 mm粒级更早进入动态碎磨状态,容易出现细粒级过粉碎.与圆锥破碎机产品相比,高压辊磨机产品在磨矿中各阶段的转折时间显著缩短,但会更早出现细粒级过粉碎.生产中通过提高高压辊磨机产品的入磨量来缩短球磨时间,在提高选厂的处理能力的同时减弱排矿产品细粒级过粉碎.

Grinding specific rate of Anshan type hematite ores was analyzed using MATLAB software. Test results showed that breakage of ore particles in the grinding process went through three inherent stages： rapid grinding of coarse size fraction,dynamic grinding of middle size fraction and single grinding of middle size fraction. Particles in 0. 043 - 0. 031 mm size fraction went into dynamitic grinding stage earlier than particles in 0. 105 - 0. 043 mm size fraction,and then overgrinding of fines occurred easily in ball mill. Compared with cone crusher products,HPGR（ high pressure grinding rolls） products had significantly shorter turning time points in three breakage stages,which means that HPGR products were ground faster with earlier occurrence of overgrinding. Given this, the increase of HPGR product tonnages into mills shortened the residence time of materials in ball mill,not only improving the capacity of mineral processing plants but also weakening overgrinding of fines.