A fluid dynamics study of a circulating fluidized bed with secondary air injection

This paper presents an experimental study on the fluid dynamics of a circulating fluidized bed with secondary air injection. The experiments were run in a 4 m high, 100 mm internal diameter riser system. The solid material was 200--920 {micro}m diameter sand. The gas temperature at the beginning of the riser was around 200 C and the superficial gas velocity varied in the 2.5--9.5 m/s range. The data obtained made it possible to suggest correlations for the pressure drop in a cyclone and in a recirculating L-valve, which are necessary to study the system pressure balance. The pressure profiles in the loop of the circulating fluidized system show the secondary air injection influence.