Lump coal derived soot formation and gas analysis during pyrolysis from fixed bed. Journal of the Energy Institute, Volume 82, Number 1, pp. 19-27(9)

The objectives of this work are to study lump coal derived soot formation and related gaseous emissions during the pyrolysis process in a fixed bed. A laboratory scale movable fixed bed, a water cooled soot collection system and an electric reactor have been designed and employed in the process. Three kinds of coals sized at 3-5 mm, have been pyrolysed in the experiments. The ash content of the soot samples on the filter has been tested and analysed by using inductively coupled plasma atomic emission spectrometer. The tar and soot have been separated by dissolving the samples in dichloromethane, and the yields of soot have been determined. The compositions of gases from the exit have been determined by gas chromatograph mass spectrometer. The results show that more tar has been converted to soot at higher temperatures and some of the saturated aliphatic hydrocarbons are condensed and polymerised to aromatic hydrocarbons. More tar has been converted to soot at longer residence times and some of the unsaturated aliphatic hydrocarbons are reformed to saturated aliphatic hydrocarbons. No small molecular compound exists at longer residence time. With high volatiles coal it is easier to form soot which releases more aromatic hydrocarbons.