Auto-Ignition Temperature of Butane and LPG at Elevated Pressures
The results of an experimental study of the dependence of the auto-ignition temperature (AIT) of various combustible gas-air mixtures on the mixture pressure and composition is reported upon. The gases investigated are n-butane and iso-butane. Also two LPG mixtures were studied. The one contained a 50/50 mole ％ mixture of propane and n-butane. The other contained 40％ of propane and 30％ each of n-butane and iso-butane. By comparing the auto-ignition limits of the LPG mixtures with the auto-ignition limits of the pure components, the influence of the different components to the auto-ignition behaviour can be estimated. The mixture pressures were varied in the range of 0.1 to 2 MPa. For the butanes the concentrations vary between 4％ and 70％. The LPG concentrations in air vary between 30％ and 70％. It is found that the auto-ignition temperatures measured are all situated in the range 500 to 580 K. In general the pressure has only a limited influence on the AIT. The pressure at which, for a given temperature, auto-ignition occurs typically reaches a minimum value for mixture concentrations between 40％ and 60％ in case of the butanes. For equal concentrations and pressures the AIT of n-butane is lower than the AIT of iso-butane. The AIT of the latter is very similar to the AIT of propane in air. The AIT of the LPG mixtures depends very much on the amount of n-butane of the gas-air mixture. In general increasing the n-butane to propane + iso-butane ratio leads to a decrease of the AIT of the mixture. Finally the auto-ignition limits of n-butane are compared with the upper flammability limits at elevated temperature and pressure previously obtained. A first conclusion is that a mixture which is too rich to sustain flame propagation, still can auto-ignite. A second conclusion from these experiments is that the linear temperature dependence of the upper flammability limit is not valid for temperatures close to the auto-ignition area of the gas mixture.
auto-ignition butane-air mixtures LPG high pressure explosion characteristics upper flammability limit
Frederik NORMAN Filip VERPLAETSEN Jan BERGHMANS
NV Adinex, Herentals, Belgium Catholic University Leuven, Department of Mechanical Engineering, Leuven, Belgium
国际会议
The 2010 International Symposium on Safety Science and Technology(2010 安全科学与技术国际会议)
杭州
英文
987-993
2010-10-26（万方平台首次上网日期，不代表论文的发表时间）