(1. 昆明理工大学冶金与能源工程学院，昆明 650093；
2. 复杂有色金属资源清洁利用国家重点实验室，昆明 650093；
3. 微波能工程应用和装备技术国家地方联合工程实验室，昆明 650093)
摘 要: 本文以低品位磁铁矿为原料，通过高温微波箱式炉加热预处理，对比研究微波连续加热和脉冲加热两种方式对矿石可磨性的影响。以粒度-20+10 mm的矿样作为研究对象，通过调整微波功率、加热时间、脉宽、周期等参数，获得两种微波加热方式的最佳条件。结果表明：连续加热的最佳参数为微波功率1000 W、加热120 s，可获得粒度-0.075 mm的物料质量分数达87.32%，比直接磨矿提高了14.32%；脉冲间歇加热的最佳参数为微波输出功率1000 W、微波加热10 s+间歇30 s、总预处理时间200 s，可获得粒度-0.075 mm物料质量分数达89.75%，比直接磨矿高出16.75%。SEM分析表明，磁铁矿经微波辐射处理，有用矿物和脉石间产生裂纹，促进脉石和矿物的分离，脉冲间歇加热方式的助磨效果比连续处理加热方式更好且能耗更低。
关键字: 微波助磨；磁铁矿；脉冲间歇式加热；连续加热；磨矿效果
（1. Faculty of Metallurgical and Energy Engineering, Kunming
University of Science and Technology, Kunming 650093, China;
2. State Key Laboratory of Clean Utilization of
Complex Non-ferrous Metal Resources, Kunming 650093, China;
3. National and Local Joint Engineering Laboratory
for Microwave Energy Engineering Application and Equipment Technology, Kunming
650093, China）
Abstract:In this paper, the raw material, low-grade magnetite, was pre-treated by microwave continuous heating and pulsed heating, respectively, in high-temperature microwave box furnace to compare the different effects of each methods on the improvement of grindability. The sample with a particle size of -20+10 mm was mainly selected as the research object. The results show that, by adjusting the parameters of microwave power, heating time, pulse width and pulse period, the best conditions for continuous microwave heating are microwave power of 1000 W and heating for 120 s, the mass fraction of materials with particle size of -0.075 mm can reach 87.32%, which is 14.32% higher than that of direct grinding. The optimum parameters for pulsed heating are microwave power of 1000 W, microwave heating for 10 s+intermittent for 30 s, and total pretreatment time for 200 s, the mass fraction of materials with particle size of -0.075 mm can reach 89.75%, which is 16.75% higher than that of direct grinding. The SEM analysis shows that the microwave radiation treatment of magnetite concentrate produces cracks between valuable minerals and gangue, which promotes the separation of gangue and minerals. In summary, the microwave pulsed heating treatment of ore has a better grinding aid effect and lower energy consumption than the microwave continuous heating treatment.
Key words:
