微波照射对鞍山式铁矿石磨矿效果的影响  

Effect of Microwave Irradiation on Grinding of Anshan-type Iron Ore

作　　者：徐宏达 孙体昌[1] 马艺闻 XU Hongda;SUN Tichang;MA Yiwen(School of Civil and Resource Engineering,University of Science and Technology Beijing,Beijing 100083,China;School of Mining Engineering,University of Science and Technology Liaoning,Anshan 114051,China)

机构地区：[1]北京科技大学土木与资源工程学院,北京100083 [2]辽宁科技大学矿业工程学院,辽宁鞍山114051

出　　处：《金属矿山》2021年第5期86-90,共5页Metal Mine

摘　　要：破碎磨矿能耗在选厂总能耗中占比较大,但其中仅有1%的能量用于新表面的生成,造成了资源的极大浪费。微波照射作为一种有效的预处理手段,能显著提升矿石的磨矿效果。为研究微波照射对鞍山式铁矿石磨矿效果的影响,以鞍山式赤铁矿为主要研究对象,开展了微波照射功率、微波照射时间、矿石块度以及冷却方式等条件试验,同时对比了鞍山式磁铁矿石的磨矿效果。结果表明:(1)微波照射能显著提升鞍山式赤铁矿石的磨矿效果,最佳的微波照射条件为:矿石块度20~25 mm、微波照射功率3 kW、照射时间45 s、水淬冷却。在此条件下,磨矿产品中-0.074 mm粒级含量为65.80%,相比未经微波处理的矿样,提高了5.57个百分点。(2)在相同的微波照射条件下,赤铁矿石的磨矿效果要明显优于磁铁矿。微波照射能显著降低鞍山式赤铁矿石和磁铁矿石的最大抗压强度,且赤铁矿石的降低程度要大于磁铁矿石。(3)SEM微观结构分析结果表明,微波照射后赤铁矿和石英之间出现明显裂痕,有助于提高选择性磨矿效果。赤铁矿石和石英的升温特性曲线表明,微波照射功率3 kW、微波照射时间60 s的赤铁矿石,其中心顶部温度可以达到600℃以上,而石英的温度几乎不随微波加热时间而变化,该特性有助于实现有用矿石和脉石矿物的有效分离。The energy consumption of crushing and grinding accounts for a large proportion of the total energy consumption in the concentrator,but only 1%of the energy is used for the generation of new surfaces,resulting in a great waste of resources.As an effective pretreatment method,microwave irradiation can significantly improve the grinding effect of ore.In order to research the influence of microwave irradiation on the grinding effect of Anshan-type hematite ore,the conditions tests of microwave irradiation power,microwave irradiation time,ore block size and cooling method were carried out,and the grinding effect of Anshan-type magnetite ore was compared.The results showed that:(1)Microwave irradiation can significantly improve the grinding effect of Anshan-type hematite,and the best microwave irradiation conditions are as follows:ore fragmentation from 20 to 25 mm,microwave irradiation power of 3 kW,irradiation time of 45 s,water quenching and cooling.Under these conditions,the contents of-0.074 mm particle size in the grinding products is 65.80%,which is 5.57 percentage points higher than that of the ore samples without microwave treatment.(2)Under the same microwave irradiation conditions,the grinding effect of hematite is significantly better than that of magnetite.Microwave irradiation can significantly reduce the maximum compressive strength of Anshan hematite and magnetite,and the reduction of hematite is greater than that of magnetite.(3)The SEM microstructure analysis results show that obvious cracks appear between hematite and quartz after microwave irradiation,which is helpful to improve the selective grinding effect.The temperature rise curves of hematite and quartz showed that the temperature at the top of the center of hematite can reach more than 600℃when the microwave irradiation power is 3 kW and the microwave irradiation time is 60 s,while the temperature of quartz almost does not change with the microwave heating time,which is helpful to realize the effective separation of useful ores and gangue m

关 键 词：微波照射 赤铁矿石 磁铁矿石 磨矿效果 

分 类 号：TD921.4[矿业工程—选矿]