(280f) Experimental Research on the Compression Behavior of Ultrafine Alumina Powders Under Gas Pressurization

The compression behavior of powder bed under gas pressurization plays a crucial role in the performance of pressurized powder pneumatic conveying systems. The compression behavior of ultrafine powder, especially nanoscale powder, is more complicated. In this study, a visualization method was employed to compare the compression behaviors of alumina powders with different particle sizes ranging from the microscale to the nanoscale. The experimental results revealed that the strong agglomeration led to a higher compressibility percentage of about 58 % for the nanoscale powders compared to the microscale powders with the percentage of about 44 % under gas pressurization. However, the compression degree of powders shows a non-monotonic relationship with particle size. In particular, the most compressible nanoscale powder exhibited the ability to significantly reduce the compressibility at a lower gas pressurization rate. This finding provides a new optimization method for the pressurized pneumatic conveying and feeding systems of ultrafine powder.