微波预处理条件对鄂西鲕状赤铁矿磨矿效率的影响  

Effect of microwave pretreatment condition on the grinding efficiency of oolitic hematite from western Hubei Province

作　　者：钱功明[1] 张博[1] 李漫漫[1] 杨蓉[1] 张慧丽[1] 

机构地区：[1]武汉科技大学资源与环境工程学院,湖北武汉430081

出　　处：《武汉科技大学学报》2016年第1期1-6,共6页Journal of Wuhan University of Science and Technology

基　　金："十一五"国家科技支撑计划项目(2007BAB15B01)

摘　　要：以鄂西鲕状赤铁矿为研究对象,采用不同功率与加热时间对其进行微波预处理,研究矿样在微波场中的升温特性,考察预处理前后矿样形貌、比表面积及孔隙率变化,分析所得矿样的磨矿效率、邦德磨矿功指数及过程功耗。结果表明,当微波功率为1~3kW时,矿石可在90s内被迅速加热至400℃以上,且升温速率随功率的增大而增加;经不同条件微波预处理后,赤铁矿与脉石颗粒间出现明显裂缝,矿石比表面积与孔隙率分别提升43.8%~51.9%和20.9%~40.0%;相同磨矿条件下,经功率为2kW、时间为45s处理后的矿样,-0.038mm和-0.074 mm粒级产品产率最高可提升37.2%和43.4%,邦德磨矿功指数最多可下降13.6%;微波预处理有助于降低磨矿过程功耗,当磨矿产品中-0.038 mm粒级产率为49.2%时,最大能耗降幅为21.4%。With oolitic hematite from western Hubei Province as the research object, microwave irradiation with different powers and heating times was employed to pretreat the ore samples. The temperature-rising characteristics of oolitic hematite in microwave field were studied. The vatiations of morphology, specific surface area and porosity of ore samples after microwave pretreatment were investigated. The grinding efficiency, Bond grinding work index and total power consumption of treated samples were analyzed. The results show that when the microwave power is in the range of 1-3 kW, oolitic hematite samples can be heated up to above 400 ℃ rapidly within 90 s and the heating rate increases with the elevation of microvave power. After pretreatment under different microwave condi- tions, obvious intergranular cracks appear on the boundaries between hematite and gangue particles, and the specific surface area and porosity of ore samples are improved by 43.8% -51.9% and 20.9% -40.0%, respectively. Under the same grinding conditions, the percentages of grinding product with size fractions of -0. 038 mm and -0. 078 mm are increased by 37.2% and 43.4% respectively, while the Bond grinding work index is reduced up to 13.6% when the microwave power is 2 kW and the heating time is 45 s. Microwave pretreatment can promote the reduction of total grinding power consumption. When the percentage of grinding product with size fraction of --0. 038 mm is 49.2%, the maximum decreasing amplitude of grinding power consumption can reach 21.4%.

关 键 词：鲕状赤铁矿 微波处理 晶界裂缝 磨矿效率 功耗 

分 类 号：TF521[冶金工程—钢铁冶金]