Brush and propagating brush discharges associated with insulating coats and the evaluation of their incedivity

2016 Fiscal Year Final Research Report

• Project/Area Number: 26350470
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Social systems engineering/Safety system
• Research Institution: National Institute of Occupational Safety and Health,Japan
• Principal Investigator: Ohsawa Atsushi 独立行政法人労働者健康安全機構労働安全衛生総合研究所, 電気安全研究グループ, 統括研究員 (20358435)
• Research Collaborator: OHUCHI Mikio 東京電機大学, 教授 ; IZUMI Fusao 産業安全技術協会 ; OTA Kiyoshi 住友化学 ; Morrow R. University of Sydney, Honorary ; Lowke J. J. CSIRO, Honorary ; Murphy A. B. CSIRO, Senior Principal Scientist ; Glor M. Swiss Process Safety Consulting GmbH, CEO ; Holdstocks P. Holdstock Technical Services ; Smallwood J. Electrostatics Solutions ; Pidoll U. von PTB
• Project Period (FY): 2014-04-01 – 2017-03-31
• Keywords: ブラシ放電 / 沿面放電 / 絶縁性コート・ライナー / 帯電 / 放電電荷 / 可燃性ガス・蒸気・粉じん / 放電着火 / 静電気障災害防止

Outline of Final Research Achievements

Insulating inner coats and liner bags often used in metal tanks, pipes, drums, etc., have sometimes caused electrostatic ignitions in chemical processes. Two types of discharge, brush discharge (BD) and propagating brush discharge (PBD), can occur on a charged insulating coat or liner in contact with a grounded conductor when a grounded object approaches it. This study is a an experimental investigation of these discharges on charged insulating surfaces with different materials and thicknesses in contact with a grounded backing plate to gain a guide for the risk assessment of ignition by the discharges on insulating coats and liners often used in chemical processes. Based on the result, we provide unified expressions of the charge transferred by BD and of a criterion for the onset of PBD with the estimation of their discharge energies for the quantitative analysis of ignition hazards associated with the coats and liners in the consideration with their permittivity and thickness.

Free Research Field

静電気安全