Propane ignition energy

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]. 

Ko, Y., Anderson, R. W. and Arpaci, V. S. Spark ignition of propane-air mixtures near the minimum ignition energy, Part I An experimental study, Combustion and Flame 83,1991, 75-87... 

Hydrogen is also one of the easiest explosives to ignite when suitably mixed with air or oxygen. For example, the ignition energy of hydrogen (H2), methane (CH4), and propane (CsHg) are 0.02,... 

Low-energy ignition of unobstructed propane-air and natural gas-air clouds does not produce damaging overpressures. 

Propane gas, C3H8, is sometimes used as a fuel. In order to measure its energy output as a fuel a 1.860 g sample was combined with an excess of 02 and ignited in a bomb calorimeter. After the reaction, it was found that the temperature of the calorimeter had increased from 25.000°C to 26.061°C. The calorimeter contained 1.000 kg of water. The heat capacity of the calorimeter was 4.643 kJ/°C. Determine the heat of reaction, in kJ/mol propane. The reaction was ... 

Effect of Pressure. An increase in pressure decreases the amount of energy required to cause ignition. In a mixture of propane, oxygen, and nitrogen, doubling the pressure decreases the minimum energy required to cause ignition by a factor of about 5. 

The measured ignition times and activation energies of propane and other n-alkanes are in good agreement with earlier work, but now show substantially smaller scatter. The activation energies of propane and the n-alkanes (n-butane, n-heptane, n-decane) and JP-10 W ere found to be similar and substantially different from that for ethylene [9]. 

An accumulation of combustible substances in terms of a precipitation of a pure hydrocarbon phase should be avoided (e.g. liquid propane or soHd acetylene in liquid oxygen (LOX)). An ignition close to a hydrocarbon phase with a subsequent combustion can transfer a lot of energy to the adjoining metal which might catch fire. 

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