微波场中锂辉石的升温及吸波特性研究  

Heating and Microwave Absorption Characteristics of Spodumenein Microwave Field

作　　者：崔立雪 余裕森 王云帆 张利波[1,2] CUI Lixue;YU Yusen;WANG Yunfan;ZHANG Libo(Faculty of Metallurgical and Energy Engineering,Kunming University of Science and Technology,Kunming 650093,China;State Key Laboratory of Complex Nonferrous Metal Resources Clean Utilization,Kunming University of Science and Technology,Kunming 650093,China)

机构地区：[1]昆明理工大学冶金与能源工程学院,云南昆明650093 [2]昆明理工大学省部共建复杂有色金属资源清洁利用国家重点实验室,云南昆明650093

出　　处：《昆明理工大学学报（自然科学版）》2023年第3期12-24,40,共14页Journal of Kunming University of Science and Technology(Natural Science)

基　　金：国家自然科学基金项目(52264030);中央引导地方科技发展资金项目(202107AA110002);昆明理工大学“双一流”创建联合专项(202201BE070001-048)。

摘　　要：硫酸焙烧法回收锂辉石中的碳酸锂是一种具有回收率高、矿石适应性好、工艺流程简单等优于其他矿石提锂的方法.为了能够在微波条件下进行硫酸化焙烧,且能够有效地提高锂辉石中锂浸出率,进行了锂辉石在微波作用下介电特性测试.利用介电谱和透射电镜等手段分析了锂辉石在硫酸介质中的介电性变化情况.试验研究以经过1 050℃和30 min焙烧后的β-锂辉石为原料,利用谐振腔测量技术讨论了β-锂辉石在微波频率为2 450 MHz条件下,表观密度、温度以及湿度对β-锂辉石介电特性的影响.研究结果表明:在不同粒度区间下,温度为250℃时,锂辉石材料对微波吸收能力效果最弱,表观密度较大的物料微波吸收能力越强;在不同湿度下,硫酸剂量是理论剂量的120%时,锂辉石与硫酸混合料对微波吸收能力最强.微波介电性能的趋势和微波升温特性的趋势相吻合.此外,对常规硫酸焙烧和微波硫酸焙烧的升温特性进行了比较,实验结果表明:微波焙烧比常规焙烧表现出更好的升温特性,这主要是因为硫酸提高了锂辉石矿料的吸波性能.本文主要通过对分析混合矿物的介电特性和加热特性进行分析,从实验效果来看,这两项工作都强调了锂辉石与硫酸混合矿物在微波硫酸焙烧过程中的的可行性和正确性,对微波硫酸焙烧实验研究提供了有利的支撑.The sulfuric acid roasting method for spodumene has a higher recovery rate of lithium carbonate,is suitable for ores,and its process flow is superior to other methods for extracting lithium from ores.In order to effectively improve the lithium leaching rate of spodumene under microwave sulfation roasting,the dielectric properties of spodumene under microwave conditions were investigated.The dielectric properties of spodumene in a sulfuric acid medium were analyzed using dielectric spectroscopy and transmission electron microscopy.The experimental study was conducted using β-spodumene as the raw material,and the resonant cavity measurement technology was employed to investigate the influence of apparent density,temperature,and humidity on the dielectric properties of β-spodumene under a microwave frequency of 2450 MHz.The research indicates that spodumene material exhibits the lowest microwave absorption ability at 250℃within different particle size ranges,while materials with higher apparent density have a strong microwave absorption ability.Under different humidity conditions,the spodumene-sulfuric acid mixture demonstrates the highest microwave absorption ability when the sulfuric acid dosage is 120%of the theoretical dosage.The trend of microwave dielectric properties aligns with the trend of microwave heating characteristics.A comparison between the heating characteristics of conventional sulfuric acid roasting and microwave sulfuric acid roasting reveals that the latter exhibits superior heating characteristics.Through the analysis of the dielectric properties and heating characteristics of mixed minerals,both studies emphasize the feasibility and correctness of using a spodumene-sulfuric acid mixture in the microwave sulfuric acid roasting process.

关 键 词：锂辉石 微波焙烧 介电特性 升温速率 

分 类 号：TF826.3[冶金工程—有色金属冶金]