Pyrolysis of Hailar Lignite: Experiments with a Tubular Reactor and a Continuous Screw Kiln Reactor

Abstract:

Pyrolysis of Hailar lignite (moisture content ~ 34.81 wt%) was investigated at temperatures ranging from 700 °C to 900 °C in two different reactors: A tubular reactor (TR) and a continuous screw kiln reactor (CSKR). Under temperature programmed-heating conditions in the TR reactor, the auto-generated steam from the lignite moisture was vaporized and swept out of the reactor by the N₂ flow during the long heating process, leading to a weakened effect on the subsequent reactions. However, in the CSKR tests all the volatiles was generated continuously while avoid the carrier gas dilution , significant interactions between the in situ steam and the intermediate products occurred. Upon comparing the two pyrolysis processes, it was found the CSKR process exhibits higher H₂ yield of 23.23 mol/kg, H₂ proportion of 49.82 vol % than those (16.97 mol/kg, 41.51 vol %) from the TR process. The results demonstrated that inherent moisture in Hailar lignite had a significant influence on the product yield, depending on the pyrolysis conditions. It was also shown that increase in temperature led to rising dry gas yield and H₂ yield.

• Periodical: Applied Mechanics and Materials (Volumes 672-674)
• Pages: 665-671
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.672-674.665
• Online since: October 2014
• Authors: Hao Jie Gao, Yue Zhao Zhu*, Hai Jun Chen, Chuan Hua Liao, Yang Du, Hao Wu
• Keywords: Fuel Gas, Inherent Moisture, Lignite, Pyrolysis, Temperature

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