Explosions ignition energy

Safety requirements (dust explosions, ignition energy). 

Ostmark, H. (1987) Laser ignition of explosives ignition energy dependence of particle size. 3e Congres International de Pyrotechnie du Groupe de Travail de Pyrotechnie Spatiale et 12e International Pyrotechnics Seminar, Juan-Les-Pins France, June 8-12, p. 241. 

If it is assumed that explosible dust will be present above the MEC, and equipment design data are not required, explosibility testing forP g, and Kg usually has no direct application. However, minimum ignition energy (MIE) testing should be considered to help determine the likelihood of ignition. Since MIE is extremely sensitive to particle size it is especially important to test a sample that is sufficiently fine to represent the worst credible case. 

Minimum ignition energy (mj) Maximum explosion pressure (psi) " Maximum rate of pressure rise. (psi/s) Maximum oxygen concentration to preyent ignition (% by volume)... 

The chance of accidental initiation is related to the energy imparted to the substance and the sensitivity of the compound. Hence the sensitivity of compounds should be established (e.g. Table 7.15) before devising appropriate control measures. (Many sensitive explosives have ignition energies of 1-45 m, while some very sensitive materials have ignition energies <1 m. )... 

The violence of an explosion is influenced by the initial pressure or pressure of the system in which the explosion takes place. Figure 7-57 illustrates this point for propane and a constant ignition energy source. For low pressure below aunospheric, the explosion reactions are reduced until they will not propagate through the fuel-air mixture [54]. 

Dust Minimum ignition temperature (°C) Minimum explosible concentration (g/l) Minimum ignition energy (ml)... 

Table 5. Representative ignition temperatures, minimum explosion concentration, and minimum ignition energy for selected dusts, from NFPA Fire Protection Handbook (National Fire Protection Association, 1986) and other sources.

Types of dust Ignition temp, of dust cloud, °C Ignition temp, of dust layer, °C Min. ignition energy (MIE), J Min. explosion cone., g/nC... 

Dust Median particle size (Mm) Minimum explosive dust concentration (9/m3) Pmax (bar g) st (bar-m/s) Minimum ignition energy (mJ)... 

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