An Apparatus and Methodology for Predicting the Dustiness of Materials

A bench-scale, impact-type chamber was developed to measure the “dustiness” of a variety of finely divided solid materials. The design of the chamber incorporates a 0.27-L container with a rotation rate of 0.8 rpm from which solids are poured onto a solid surface 25 cm below. Suspended particulate matter is collected on a 47-mm glass fiber filter sampler in the chamber lid which draws air through side vents at an 8.3-L/min sampling rate. The measure of dustiness is the mass of suspended particulate material collected during a 10-min period beginning just before the pouring, divided by the total mass dropped in the chamber. A total of 36 tests of 14 solids were performed in the dustiness chamber. These test materials consisted of inorganics, carbonaceous substances, and dyes. All of the test materials were characterized for the physical properties which might affect dustiness potential. These included bulk density, particle-size distribution, moisture content, and angle of repose. Both dried and humidified...