- Author
-
VanDolah, R. W.
|
Mason, C. M.
|
Perzak, F. J. P.
|
Hay, J. E.
|
Forshey, D. R.
- Title
- Explosion Hazards of Ammonium Nitrate Under Fire Exposure.
- Coporate
- Bureau of Mines, Pittsburgh, PA
- Keywords
-
explosion hazards
|
ammonium nitrate
|
exposure
|
explosions
|
combustion
|
fire tests
|
deflagration
|
detonation
|
porous beds
- Identifiers
- detonability of ammonium nitrate and related systems; combustion of ammonium nitrate in porous beds; mathematical analysis of the possibility of a deflagration to detonation transition; materials used; modified card gap tests; projective impact test; mathematical development of the conditions for deflagration to detonation transition in ammonium nitrate
- Abstract
- An attempt has been made in this investigation to define the conditions under which ammonium nitrate (AN) might detonate as a result of involvement in fire. The initiation of detonation by shocks derived from explosives or from projectile impact was investigated as a function of temperature and charge diameter. A new technique was devised to investigate the burning of raw and contaminated AN under pressure. No transition to detonation in AN was obtained in the burning experiments. The critical diameter for detonation of fertilizer-grade AN was found to be quite small when the AN was at temperatures just below melting point; this indicates that initiation of detonation may be less difficult at elevated temperatures but such initiation by gas-phase detonation was shown to be unlikely. Transition from burning to detonation was obtained with AN intimately mixed with fuels that included polyethylene, paper, and fuel oil when these were contained in vessels with restricted vents. However, the experimental results supported by an analytical study indicate that the initiation of detonation in AN from fire exposure in normal storage and from transportation incidents is quite improbable. The detonation of AN in recent incidents more likely may have resulted from the effects of adjacent explosions.