Effects of Pyrolysis Conditions on Coal Devolatilization (original) (raw)

ACS Division of Fuel Chemistry, Preprints, 1983

Abstract

The formation and evolution of PAH species in coal devolatilization is observed to be a sensitive function of the mix of molecular species present in the parent coal. Through high volatile bituminous coals and within moderate heating conditions, PAH yields increase with apparent aromaticity of the coal. Those coals having the greater aromaticity, as indicated by infrared absorption characteristics, give consistently greater tar yields than less aromatic samples. Such coals also show less variation in tar yields with changes in heating rate. For moderate heating rates to final temperatures less than 1000/sup 0/ C, the coal nitrogen evolution mirrors the parent coal evolution as char, tar or light gas species on a mass fraction basis. Heating rates of 1/sup 0/ C/sec or less are observed to lower tar yields of bituminous coals while increasing char and light gas yields. On the other hand, programmed heating rates of 10/sup 5/-10/sup 6/ /sup 0/C/sec also result in a decrease in tar yields with an increase in solid species products. A fraction of these solids appear to be soot particles. Gaseous yields of coals subjected to such high thermal fluxes show C/sub 2/H/sub 2/, CO, CH/sub 4/, HCN, C/sub 2/H/sub 4/ and polyacetylenesmore » as the predominant gas phase species.« less

James D Freihaut hasn't uploaded this paper.

Let James know you want this paper to be uploaded.

Ask for this paper to be uploaded.