The potential of sufficient static electricity for ignition during tanker washing
Article first published online: 17 JUN 2004
Copyright © 1997 American Institute of Chemical Engineers
Process Safety Progress
Volume 16, Issue 1, pages 25–31, Spring 1997
How to Cite
Chopp, R. and Pape, R. (1997), The potential of sufficient static electricity for ignition during tanker washing. Proc. Safety Prog., 16: 25–31. doi: 10.1002/prs.680160110
- Issue published online: 17 JUN 2004
- Article first published online: 17 JUN 2004
Waste-derived fuel is an environmentally friendly method for destroying waste and recovering the energy value it contains. The fuel is characterized as a mixture of various solvents with a flashpoint in the flammable range. In addition to these solvents, the waste fuel contains solid material. During the transfer of this material to storage tanks, some of the solid material is is left behind in the tankers and rail cars. The ideal solution to remove this solid material is to wash the tank vehicle with the same waste fuel. With the waste fuel being in the flammable range, there is a concern about the washing operation causing ignition due to static electricity.
Scaled experiments were conducted to assess the potential for static electricity to cause ignition. Although several ignition mechanisms were assessed, this paper is concerned with the charged mist caused by the high velocity solvent jet impinging on the tank wall. Isopropyl alcohol, mixed xylenes, and mineral spirits were evaluated. An aerosol electrometer was used to measure charge per unit volume of mist sampled. Discharge generation was assessed using an analytical model which estimates electric field corresponding to measured charge density for various configurations.