(287d) Granular Attrition Effect on the Electrostatic Behavior in a Pneumatic Conveying System

Electrostatic charge generation and attrition of granular flow are commonly encountered in particle-processing industries and usually cause many problems. However, little attention has been given to address these issues. The present work aims to investigate granular attrition effects on the electrostatic charging behavior in a pneumatic conveying system and further look into the influence of single-particle shape and size on the charging characteristics. Three instruments, namely the electrometer, Modular Parametric Current Transformer (MPCT) and Faraday Cage were used to study the electrostatic behavior in the pneumatic conveying system and a separate facility coupled with the Faraday Cage was designed to study the charge variation of single attrited granules from the conveying system. As attrition progressed in the pneumatic conveying system, electrostatic charges generated were observed to increase, as characterized by the induced current measured with the MPCT. Particle charge densities were higher for smaller particles and also affected by the shape of the granules. The electrostatic charge generation of the overall pneumatic conveying system was found to be well correlated with that occurring at the single-particle level, taking into account the shapes and sizes of the granules. It was also correlated with the attrition processes taking place in the system.