In situ monitoring of the acoustic agglomeration of fly ash particles

Acoustically-induced agglomeration of fly ash particles has the potential to reduce the particulate loading in the exhaust gases from coal burning combustors by improving the performance of fly ash removal devices. The objective of this investigation was to directly measure differences in size distributions and number densities of ash particles in the presence and absence of acoustic fields. A single particle counter laser analyzer (PCSV-P) was used to measure particle size distributions and number densities of fly ash particles in an Entrained-Flow-Reactor. After evaluation of the reproducibility of the measurements made by the PCSV-P under a fixed set of experimental conditions in the absence of an acoustic field, the measurements were repeated in the presence of an acoustic field over a range of frequencies (440-1,000 Hz) and Sound Pressure Levels (140-150 dB). The measured differences in the particle size distributions and number densities were attributed to acoustic agglomeration of the fly ash particles.