Experimental research on acoustic agglomeration of particles with bimodal distribution

In this paper, the effects of particle agglomeration and fragmentation are explored from the microscopic stress. The bigger the sound pressure level, the smaller the critical particle size of aggregate will be. The acoustic agglomeration of inhalable particles in 0~200 μm bimodal particles is studied by experiments. The influence of sound intensity and acoustic frequency on the acoustic agglomeration are studied under the condition of 500~3 500 Hz and 70~140 dB. Under 120 dB, the best frequencies of 1 800~2 300 Hz exist for bimodal particles, and the agglomeration efficiency can reach 25%~30%. In the experimental range of 70~120 dB, the agglomeration efficiency increases first and then decreases. Large particles are broken and small particles increase in the particle size distribution under 140 dB. For the treatment of inhalable particles in flue gas of coal-fired power plant by using acoustic agglomeration technique, it is necessary to consider the crushing effect of the sound field, and recommended to arrange the acoustic chamber behind the electrostatic precipitator.