我国贫铁矿石磁选预选现状及发展趋势

介绍了磁选预选技术在贫铁矿石选矿中的应用情况。以高效圆锥破碎机、自磨/半自磨机和高压辊磨机为代表的新型碎磨设备使贫铁矿石的预选粒度有效降低，为预选抛尾提供了有利条件。磁选技术既可以实现贫磁铁矿石粗碎产品（约350~400 mm）的预选抛尾，也可以实现超细碎产品（小于3 mm）的预选抛尾，并可根据矿石性质及现场生产实际采用干式或湿式预选工艺。永磁辊式强磁选机可对中碎或细碎后的弱磁性贫赤铁矿石进行预选，电磁立环脉动高梯度磁选机对细粒级（小于3 mm）贫赤铁矿石的预选效果较好。指出了未来贫铁矿石磁选预选的主要发展趋势为高效碎磨设备和工艺的基础性研究，磁选设备对贫铁矿石性质和生产工艺适应性的研究，弱磁性贫赤铁矿石永磁强磁预选技术的深入研究与推广应用。

Application and Development Tendency of Magnetic Separation for Pre-concentration of Lean Iron Ore in China

The application of pre-concentration technology on beneficiation of lean iron ore was described. Sufficient con-ditions of pre-concentration for lean iron ore were provided by the effective reduction of the feeding size as the result of the ap-plication of new types crushing and grinding machines of which high efficiency cone crusher,AG/SAG and high-pressure grind-ing roller were the chief representative. Pre-concentration for products of 350~400 mm from coarse crushing and -3 mm from ultra-finely crushing of lean magnetite could be realized by magnetic separation. And dry or wet process of pre-concentration could be determined according to the different processes. High-intensity permanent magnetic separator provides a new way for pre-concentration of lean hematite after middle crushing. Vertical ring pulsating high gradient magnetic separator has a better effect on the pre-concentration for -3 mm lean hematite. The development tendencies in pre-concentration of lean iron ore are investigation of efficient crushing equipment and process,research on adaptability of magnetic separator to the characteristics of lean iron ore and production environment,further research and application of permanent high-intensity magnetic pre-concentra-tion for lean hematite.