The Microstructure of Pulverized Coal-Air Flames, I. Stabilization on Small Burners and Direct Sampling Techniques

Abstract

The successful stabilization of unaugmented, laminar, premixed, flat flames of coal dust-air on 6.3-cm diameter burners is described. The method of feeding the coal and achieving a uniform dust dispersion is presented and the behavior of the flame is discussed, including its thermal interaction with the burner grid. Procedures and apparatus for the direct sampling, through sonic orifices, of both gaseous species and particulates are presented. Emphasis is placed on the use of direct, molecular beam, mass spectrometry to provide broad detection capability, rapid quenching and high spatial resolution, The initial, bright reaction zone of rich flames of pulverized Pittsburgh Seam coal in air can be probed with a spatial resolution of the order of a millimeter and time resolution of the order of milliseconds