The impact of microwave drying technology on the drying kinetics of phosphate ore

To address the technical bottlenecks of traditional phosphate drying methods, including high energy consumption and unstable product quality, this paper proposes an energy-saving dehydration method based on microwave radiation. The effects of initial moisture content, initial mass, and microwave power on the drying kinetics of phosphate ore were investigated. The results show that microwave power, moisture content, and initial mass are positively correlated with drying rate. Four kinetic models were constructed to analyze the drying process of phosphate ore under microwave action, including Quadratic, Page, Modified Page, and Wang-Singh models. The results indicate that the Modified Page model has a higher fitting accuracy. Fourier Transform Infrared (FT-IR) spectroscopy analysis shows that after microwave treatment, the intensity of the infrared absorption peak corresponding to water in the sample significantly decreased, proving effective removal of moisture. Additionally, no shift was observed in other characteristic absorption peaks in the spectra, confirming that the treatment process did not alter the primary chemical composition of the sample. This breakthrough overcomes the limitations of traditional thermal drying, which often leads to the destruction of the mineral lattice. The activation energy (13.1872 g/W) determined from the Arrhenius equation reveals the mechanism of moisture desorption during microwave drying. This study provides both theoretical and empirical support for the application of microwave drying technology in the field of phosphate mineral processing.