A novel particle separation technique using 20-kHz-order ultrasound irradiation in water

9th International Symposium on Cavitation

Muramatsu, Hiroya^1 ; Yanai, Sayuri^2 ; Mizushima, Yuki^1 ; Saito, Takayuki^3

Graduate School of Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu, Shizuoka

432-8561, Japan^1

Graduate School of Engineering, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu, Shizuoka

432-8561, Japan^2

Research Institute of Green Science and Technology, Shizuoka University, 3-5-1 Johoku, Naka-ku, Hamamatsu, Shizuoka

432-8561, Japan^3

关键词: Flocculation mechanisms;    Manipulation techniques;    Particle diameters;    Particle separation;    Separation process;    Stationary positions;    Ultrasound irradiation;    Ultrasound techniques;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/656/1/012117/pdf
DOI  :  10.1088/1742-6596/656/1/012117

来源: IOP

【 摘 要 】

Ultrasound techniques such as washing, fine-particle manipulation and mixing have been investigated. MHz-band ultrasound was usually used in the previous work, and studies of kHz-order ultrasound are very rare. In the usual manipulation technique, μm- order particles are targeted due to wavelength limitations. We discovered an interesting phenomenon that holds promise for a novel particle separation technique using kHz-order ultrasound. Here, particles with sub-mm- or mm-order diameters were flocculated into a swarm in water irradiated by 20-kHz ultrasound. To develop a practical separation process, we investigated the stationary position and dia. of the particle swarms and the sound- pressure profiles in a vessel, as well as the flocculation mechanism, by varying the irradiation frequency, water level, particle diameter and particle amount. The primary stationary position corresponded to the wavelength calculated from the resonant frequency regardless of the particle diameter. Subtle changes in the frequency and water level resulted in a significant change in the stationary position. Based on these results, we propose a new separation process based on the particle diameter for sub-mm- or mm-order particles.