Efficiency and stability of lump coal particles swirling flow pneumatic conveying system

To clear the swirling flow pneumatic conveying performance for blocky fuel particles, particularly for lump coal particles, a side inlet guide vane swirling generator was developed and employed to study the efficiency and stability of lump coal particles in swirling flow pneumatic conveying. In total, 32 pilot scale tests for different conditions, including different airflow rates, solid mass flow rates, and swirling intensities, were conducted in this paper. The efficiency and stability of lump coal particles in swirling flow pneumatic conveying are thoroughly discussed by considering the static pressure loss and pressure fluctuation standard deviation. The pressure characteristics for different conveying stages and frequency spectrum constituents of the static pressure are also discussed. The results show that the swirling flow has better energy preservation characteristics and conveying performance in proper conditions. Four main factors contribute to the static pressure fluctuation in three different frequency bands. The results also show that a low mean gas velocity with a medium swirling intensity and a high mean gas velocity with a weak swirling intensity can improve the conveying stability. The swirling flow is more stable at the front of the pipeline; meanwhile, the axial flow is better in the second half. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.