Design and Characterization of an Improved Screw-Assisted Rotary Feeding System for Aerosolization of Ultra-Small Quantities of Particulate Solids

Abstract

Many previous studies have examined solid-state particle discharge systems. However, several drawbacks have been encountered in terms of laboratory-scale particle feeding systems (e.g., high feeding rates, discontinuous feeding characteristics, the absence of long-term stability, and the use of high carrier gas volume rates). In this study, a state-of-the-art screw-assisted rotary feeding system was developed and evaluated in terms of aerosolization characteristics such as particle number concentration, geometric mean diameter, and geometric standard deviation. The various experimental conditions included changes in the rotational speed of the rotor, changes in the number of rotor grooves, and the existence or nonexistence of screw operation. Calcium carbonate (CaCO 3 ) powder was selected as the discharged sorbent particle. To verify the performance of the designed feeding system, we measured number concentrations with and without operation of the screw. Uniformity (i.e., the steadiness of feeding charac...