Fire Safety Science Digital Archive

This is a laboratory report in which is described a small-scale hydrogen diffusion flame, burning in an atmosphere of argon and oxygen, the flame being used as a means of ensuring complete combustion of hydrogen cyanide and acetonitrile fuels. Qualitative and quantitative analysis of the combustion products shows that the combustion processes of both cyanides may be similar and that the nitrogen content of each cyanide is released only as oxides of nitrogen or molecular nitrogen. The relative yields of oxides of nitrogen and molecular nitrogen are dependent upon the concentration of cyanide in the flame and the ratio N2//NOx varies between about 0.4 and 3.0 over the range of cyanide injection rates used in this report. A low concentration of cyanide tends to favour the production of oxides of nitrogen. Experiments with a relatively cold flame using a vitiated diffusion flame atmosphere show that the production of oxides of nitrogen from the combustion of cyanide fuels is largely independent of flame temperature.