Study on the Circulating Flow Rate of Rice Husk-Quartz Sand Mixture Particles in a Dual-Circulating Fluidized Bed

Abstract

In order to more accurately simulate the flow characteristics of biomass particles in biomass gasification process, an experimental study was conducted on the circulating flow rate of rice husk-quartz sand mixture on a self-built dual circulating fluidized bed cold experimental system. The circulation flow rate increased with the increase of the gasification chamber wind speed (Ua), but the growth trend gradually slowed down. With the increase of the mass fraction of rice husk (Xr) in the mixed material, the circulating flow rate showed a decreasing trend under various operating conditions. The Xr in the circulating material basically showed a decreasing trend, and increased with the increase of the wind speed of riser (Ur).The trend of increase in the lower wind speed interval was larger. After a certain wind speed value was reached, the increase trend of particles gradually became slower, and the circulating material mass fraction Xr showed a decreasing trend, and the decreasing trend gradually increased; with the increase of the initial material mass (mint),the flow rate of material circulation increased to a certain extent. The Xr in the mixed material gradually increased. Under the conditions of the respective mass fraction of mixed material, the particle size of quartz sand(dp) in the mixed material increased, the circulating flow rate of the particles gradually decreased, and the mass fraction of biomass in the riser decreased gradually.