Electrostatic discharge mechanisms and dynamic characteristics of different polarity powders in the Silo

• Published in: Powder technology Vol. 441; p. 119819
• Main Authors: Zhang, Gaoqiang, Wang, Qiao, Liang, Cai, Chen, Xiaoping, Ma, Jiliang
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.05.2024
• Subjects: Charge polarity; Charged powder; Discharge mechanism; Electrostatic discharge; Silo; Charged powder; Silo; Charge polarity; Electrostatic discharge; Discharge mechanism
• ISSN: 0032-5910; 1873-328X
• DOI: 10.1016/j.powtec.2024.119819

Electrostatic discharge in powder silos poses a significant safety hazard due to the risk of fire or explosion. However, the underlying discharge mechanisms are not fully understood. This study aims to improve the comprehension of electrostatic discharge dynamics and mechanisms by introducing a fluid discharge model for charged powder silos. The model validation is carried out by examining discharge patterns and electric field variations. The investigation of the electrostatic field and potential distribution prior to discharge helps to comprehend the discharge conditions. The discharge modes and evolution laws of different polarity powders are explored to reveal disparities in discharge phenomena. These disparities are further scrutinized in relation to electron density, space charge, electric field, and potential. To elucidate the discharge mechanism, the electric field distortion caused by space charge, electron existence time, and migration law are analyzed. The electrostatic and diffusion effects are the main reasons for the discharge differences. [Display omitted] •A fluid discharge model is established to investigate the electrostatic discharge in the silo.•The electrostatic field and potential of an industrial silo before discharge are explored.•The dynamic process of electrostatic discharge in silos is analyzed.•The electric field and potential of different polarity powder discharge are compared.