Effect of Particle Size on Dielectric Properties and Microwave Heating Characteristics of Ludwigite

doi:10.12068/j.issn.1005-3026.2018.10.010

Abstract

Abstract: The cavity perturbation method was used to measure the dielectric properties of ludwigite of different particle sizes at the frequency of 2.45GHz with the temperature ranging from 20 to 800℃， and heating characteristics under a microwave field were also measured.The results showed that with the decrease of particle size， the filling layer porosity of the ore sample decreases， while the dielectric properties and the heating rate increase.When the temperature is higher than 200℃， the thermal decomposition can generate a large number of micro-voids which increases the porosity， and the dielectric properties tend to be decreased， resulting in a reduce of heating rate during microwave heating.The effect of particle size on the dielectric properties and temperature rising characteristics of ludwigite provides a theoretical basis for the application of microwave in the fields of metallurgy and saving energy consumption.

Key words: ludwigite, dielectric properties, microwave heating characteristic, particle size, heating rate

CLC Number:

TF04

LIU Ya-jing， JIANG Tao， WANG Jun-peng， LIU Chen-hui. Effect of Particle Size on Dielectric Properties and Microwave Heating Characteristics of Ludwigite[J]. Journal of Northeastern University Natural Science, 2018, 39(10): 1418-1422.

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