Ozone Flammability and Its Affect On the Lower Flammable Limit of Simple Hydrocarbons

As a result of ozone’s strong oxidizing capabilities and ease of generation on an as-needed basis, ozone applications in process operations are gaining momentum.  Previous work has demonstrated that ozone is flammable at high concentrations with a lower flammable limit of 8.4 vol.% in oxygen.   However, there is limited data regarding the effect of ozone on the lower flammable limit of other gases known to be flammable in air.  This work investigated the lower flammable limit of methane, ethane, and propane in various concentrations of ozone at atmospheric pressure and temperature.  The tests were conducted in a 2-L vessel using a fuse wire ignition source at 1 percent ozone intervals spanning from no ozone to the LFL of ozone in the vessel.   It is anticipated that the addition of ozone will decrease the LFL of each flammable gas as the concentration of ozone increases.