摘要
从微观受力角度探索颗粒(Particulate Matter,PM)团聚和破碎效果,声压级越大,团聚体临界粒径越小。通过实验研究了0~200μm的双峰分布颗粒物中可吸入颗粒在声场中的团聚效果。在500~3 500 Hz、70~140 d B声场条件下,研究了声波频率和声场强度对声波团聚的影响。在120 d B的声场条件下,双峰分布颗粒团聚存在的最佳频率范围为1 800~2 300 Hz,团聚效率达到25%~30%。在70~120 d B实验范围,团聚效率随声压级的增加先增后减。在140 d B时,大颗粒明显破碎,小颗粒增多。将声波团聚技术应用到燃煤电站烟气中的可吸入颗粒物处理中,需要同时考虑声场的破碎作用,建议将声波团聚室布置在电除尘器之后。
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 d B. Under 120 d B, 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 d B, the agglomeration efficiency increases first and then decreases. Large particles are broken and small particles increase in the particle size distribution under 140 d B. 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.
出处
《声学技术》
CSCD
北大核心
2017年第6期516-521,共6页
Technical Acoustics
基金
国家自然科学基金项目(11674093)
关键词
双峰分布颗粒
声波团聚
受力分析
声压级
频率
bimodal distribution particles
acoustic agglomeration
force analysis
sound pressure level
frequency
