Acoustic agglomeration to control inhalable particulate emission from coal-fired power plants

High intensity acoustic field was applied to aerosol to remove fine particles (PM_2.5) from coal fired power plants and control air pollution of inhalable particles (PM₁₀), which changed particle size distributions and made fine particles beome larger ones which are easier to be precipitated with a traditional separator. Acoustic agglomeration experiments were carried out in a 1-5 kHz and 110-140 dB traveling wave field with redispersed fly ash collected from the baghouse filter of a coal-fired power plant. Dust loading mass concentration was 1-5 g/m³. Particle size distributions in the experiments were measured on line using the impactor and the laser particle sizer MS-2000, and effects of acoustic intensities and frequencies on agglomeration were obtained. Results from the impactor showed that PM_2.5 and PM₁₀ was reduced by 52%-63.6% and 35.6%-53.3% respectively in the 1.72 kHz and 140 dB traveling wave agglomeration experiments.