Contamination particles make an oxygen system more vulnerable to fire hazard as they provide a large surface area with reduced minimum energy of ignition. Adiabatic compression, resonance, solid friction, flow friction, and promoted ignition have acted as the source of ignition in oxygen systems. In this paper, static electricity generated in solid particles is proposed to be another possible source of ignition. It is known that the movement of particles in a system results in the buildup of static charges in them. This static electricity, if supported by suitable geometric configuration and grounding of metal projections, may lead to propagating brush discharge (PBD) and provide the energy needed for initiation of fire. Particles with low auto-ignition temperature, particularly in dispersed state, may help in initiating the fire, while metal particles may aid the propagation because of their high combustion energy. In this paper, we have determined the velocity profile utilizing the FLUENT code and calculated the charge generated in particles, exploring the ignition probability of equipment in oxygen environment through electrostatic discharge. We have also attempted to perform preliminary calculation to determine charge density and the electric field strength required for brush discharge. Computational fluid dynamics analyses on globe valves reveal the presence of probable areas of particulate accumulation in the valve. The decrease in minimum ignition energy (MIE) in the environment of high pressure, high temperature, high purity of oxygen, low humidity, small particles, high dielectric constant, low thickness of insulating layer, and high resistance of the deposited dust layer facilitates occurrence of PBD, which may cause ignition. Adiabatic heating may aid combustion by lowering the MIE of particles. Experiments have been proposed for verification of the hypothesis and analytical calculations presented by the authors. The paper may give a new insight into the possible causes of oxygen fire.
Author Information
Oza, Aditi
Indian Institute of Technology, Kharagpur, West Bengal, India
Ghosh, Sudipto
Indian Institute of Technology, Kharagpur, West Bengal, India
Chowdhury, Kanchan
Indian Institute of Technology, Kharagpur, West Bengal, India
Domestic orders are delivered via United Parcel Service (UPS) or United States Postal Service (USPS). Transit
times average 3 to 5 business days. Please be aware that UPS will not deliver packages to Post Office Boxes.
International orders are delivered via courier post services which can be either a postal service, courier
service, or a combination of both. Standard Service is untraceable. Please allow 4-7 weeks for delivery.
Please be aware that carriers will not deliver packages to Post Office Boxes. Because of the variability of
customs processes and procedures in different countries, ASTM International cannot guarantee transit times to
international destinations. Customs duty and taxes are the responsibility of the consignee.
Shipping & Handling charges follow the rate schedule, below:
Order Total
Shipping & Handling Fee (US Domestic)
Up to $50.00
$18.72
$50.01 to $100.00
$20.80
$100.01 to $150.00
$29.52
$150.01 to $250.00
$39.09
$250.01 to $500.00
$56.25
$500.01 to $750.00
$76.42
$750.01 to $1000.00
$93.15
$1000.01 to $1500.00
$121.27
$1500.01 to $2500.00
$158.38
$2500.01 to $4999.00
$209.04
$5000.00 to higher
FREE
Order Total
Shipping & Handling Fee (International)
Up to $50.00
$68.72
$50.01 to $100.00
$70.80
$100.01 to $150.00
$79.52
$150.01 to $250.00
$89.09
$250.01 to $500.00
$106.25
$500.01 to $750.00
$126.42
$750.01 to $1000.00
$143.15
$1000.01 to $1500.00
$171.27
$1500.01 to $2500.00
$208.38
$2500.01 to $4999.00
$259.04
$5000.00 to higher
FREE
Shipping and Handling charges are approximate. Additional charges may be incurred if your order requires multiple shipments. This does not apply to complete sets and sections.