Pyrolysis reaction characteristics and influencing factors of deep coal

doi:10.3969/j.issn.1006-6535.2026.01.007

Abstract

Abstract: Underground coal gasification(UCG)is an efficient method to directly convert deep coal into coalbed methane(CBM),meeting energy needs while reducing environmental impact.In order to effectively utilize deep coal resources,this study used deep coal from the Liaohe Basin as an example to clarify pyrolysis reaction characteristics and influencing factors in the deep coal gasification process.Experiments were conducted to investigate the effects of heating rate and pressure on the pyrolysis behavior and product characteristics of coal samples,and to explore the patterns of gas release during pyrolysis and the variations in product composition.The results show that for Liaohe deep coal,the optimal heating rate is 10 ℃/min,at which the semi-coke yield increases significantly with increasing pressure.Pressure has a notable influence on the composition of gaseous products:at 0.1 MPa,the pyrolysis gas consists mainly of H₂ and CO,whereas at 4.0 MPa the CH₄ content is highest at 47.2%.This study provides theoretical support and technical reference for the underground coal gasification of deep coal in the Liaohe Basin.

Key words: deep coal, coalbed methane, pyrolysis, heating rate, Liaohe Oilfield

CLC Number:

TD841

WANG Xiyou, WANG Guodong, WU Fangjie, WANG Zhongyuan, ZHAO Shuang, SHI Li. Pyrolysis reaction characteristics and influencing factors of deep coal[J]. Special Oil & Gas Reservoirs, 2026, 33(1): 60-65.

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