Formation of carbon and related materials in diffusion flames

Abstract

There is considerable interest in this subject at the present time, due not only to its intrinsic scientific appeal, but also in connection with several applied combustion processes, e.g., the smokeless combustion of bituminous coals, the use of flames with high radiant output for steelmaking and other purposes, and the preparation of carbon black. Previous approaches to the problem of carbon formation in flames may be divided into three sections: (1) Empirical studies of the smoking tendencies of fuels, the aim being to correlate struccalled inverted) flame and (2) a normal flame working at subatmospheric pressures. The former has been used for the greater part of the work and its suitability appears to arise from its relatively low temperature (see below) and also because it is self-quenching, i.e., the reaction products pass into an atmosphere of cold fuel. There appears to be surprizingly little previous recorded work with reversed flames. They were referred to in a previous communication from this laboratory 19 in relation to an apparent expansion phenomenon arising from the addition of sodium salts to flames. A preliminary publication of their use in carbon formation studies