(303g) A Novel Brush Feeder for the Pneumatic Delivery of Small Particles at Steady Feed Rates

A novel brush type feeding system was designed and constructed to consistently feed particles to an aerosol type reactor in the range of 1-2 mg/second. The feeder consists of a sealed hopper, a metering system based on a rotating brush, and a balance to monitor the change in mass. Accurate feed rates have been obtained by adjusting the brush rotation rate based on the real-time mass measurement to compensate for small fluctuations due to inherent variability. A carrier gas with a typical flow rate of 1 slpm is used to remove the particles from the feeder and pneumatically transport them to the reactor. The carrier gas flow rate and particle feed rate can be adjusted independently for added versatility. The specific application for this feeder was to dispense biomass particles in the <150 µm range to a laboratory scale biomass gasifier, but it has shown promise for use with a variety of particulate feeds.