Effect of Gas Jet on Agglomeration of Inhalable Particles

The turbulent-induced agglomeration behaviors of inhalable particles were investigated in this paper. A turbulent gas jet was introduced into the particle agglomeration chamber to generate the local turbulent field. Inhalable particles were driven by turbulence to collided and yield agglomeration. The agglomeration efficiency of inhalable particles was determined by the measurement of the particles mass concentration from a cascade impactor and number concentration using a laser particle counter. Experimental findings indicated the mass and number removal efficiency increased with increasing Reynolds number at jet exit and velocity ratio of jet to cross flow. The gas jet at the angle of 90 degrees achieves high removal efficiency. Increasing relative humidity in chamber may improve the aggregate efficiency of particles up to the maximum removal. Increasing initial concentration of fly ash causes decreasing removal efficiency of inhalable particles. The single-stage removal efficiency revealed that particle diameter had an influence on the agglomeration process. For inhalable particles, the small particles (< 1 >mu m) were easy to be removed in turbulent-induced agglomeration, but mid-size particles (1-5 mu m) were difficult to remove.