Influence of Pyrolysis Temperature on the Gaseous Products of Lignite

Abstract

Temperature-programmed pyrolysis of SL-lignite from Xilinhaote was investigated. The solid and gaseous pyrolysates were analyzed by means of gas chromatography(GC) and X-ray diffraction(XRD). The weight percents of surface moisture, ash, C, H and S increase with increasing the pyrolysis temperature in solid pyrolysates, while the volatile matter is contrary. The cracking reaction occurs before 600°C, the consolidation reaction happens between 600°C and 650°C, while the polycondensation or secondary reaction appears after 650°C. Calcium sulfide is formed by the process of decomposition of calcium sulphates at 900°C. The solid pyrolysates become more graphitic with increasing the pyrolysis temperature.