Effects of microwave pretreatment on the grinding characteristic of coal

The influence of microwave pretreatment on the heating response, moisture content, surface morphology, grindability, and liberation of coal were investigated. The results show that microwave irradiation has a weak effect on the chemical composition, but can reduce moisture content significantly. Intuitionistic evidence was discovered that microwave energy can induce micron cracks on the interface among different minerals. The results of grinding tests show that microwave pretreatment can remarkably promote the fine grinding of coal. Density analysis shows that the liberation degree of grinding products increases with the microwave pretreatment time due to the auxiliary grinding and selective heating effect of microwave radiation.