New instrument for tribocharge measurement due to single particle impacts.
During particulate solid processing, particle-particle and particle-wall collisions can generate electrostatic charges. This may lead to a variety of problems ranging from fire and explosion hazards to segregation, caking, and blocking. A fundamental understanding of the particle charging in such situations is therefore essential. For this purpose we have developed a new device that can measure charge transfer due to impact between a single particle and a metal plate. The device consists of an impact test system and two sets of Faraday cage and preamplifier for charge measurement. With current amplifiers, high-resolution measurements of particle charges of approximately 1 and 10 fC have been achieved before and after the impact, respectively. The device allows charge measurements of single particles with a size as small as approximately 100 microm impacting on the target at different incident angles with a velocity up to about 80 m/s. Further analyses of the charge transfer as a function of particle initial charge define an equilibrium charge, i.e., an initial charge level prior to impact for which no net charge transfer would occur as a result of impact.
Watanabe
Hideo
H
Institute of Particle Science and Engineering, University of Leeds, Woodhouse Lane, Leeds, West Yorkshire LS2 9JT United Kingdom.
Ghadiri
Mojtaba
M
Matsuyama
Tatsushi
T
Ding
Yu Long
YL
Pitt
Kendal G
KG