淮北煤田祁东煤矿煤层气含量与组分特征及影响因素分析

Analysis of Content, Component Characteristics and Influence Factors of Coalbed Methane of Qidong Coalmine in the Huaibei Coalfield

摘要: 为探究地质因素对煤层气含量和地球化学特征的影响，以淮北煤田祁东煤矿为研究对象，采用现场解吸法和色谱–质谱法分别对研究区3-2、8-2和9号煤储层含气量和煤层气组分进行了分析。结果表明：3-2煤层含气量为2.41~9.42 m³/t，CH₄含量为72.07%~94.69%，CO₂为1.93%~6.42%，N₂为0.4%~21.73%；8-2煤层含气量为1.39~12.19 m³/t，CH₄含量为74.19%~96.67%，CO₂为2.6%~8.16%，N₂为0.15%~ 30.48%；9煤层含气量为6.56~13.84 m³/t，CH4含量为75.88%~96.42%，CO₂为0.6%~7.2%，N₂为0.46%~17.41%。9煤层含气量与水分和灰分呈弱相关关系，但CH₄浓度几乎不受煤质特征影响。另外，8-2煤层含气量和CH₄含量与埋深呈正相关关系，N₂和CO₂含量与埋深呈负相关关系。

Abstract: In order to explore the influence of geological factors on content and component of coalbed methane (CBM), the Qidong coalmine of the Huaibei Coalfield was used as the research object, and the desorption method and chromatography-mass spectrometry method were used to analyze the gas content and CBM components of No. 3-2, No. 8-2 and No. 9 CBM reservoirs, respectively. The results show that the gas content of the No. 3-2 CBM reservoir is 2.41~9.42 m³/t, the CH₄ concentration is 72.07%~ 94.69%, the CO₂ concentration is 1.93%~6.42%, and the N₂ concentration is 0.4%~21.73%; The gas content of the No. 8-2 CBM reservoir is 1.39~12.19 m³/t, the CH₄ concentration is in the range of 74.19% to 96.67%, CO₂ concentration is 2.6%~8.16%, and N₂ content ranges from 0.15% to 30.48%; The gas content of No. 9 CBM reservoir is 6.56~13.84 m³/t, with CH₄ concentration ranging from 75.88% to 96.42%, CO₂ concentration ranging from 0.6% to 7.2%, and N₂ concentration ranging from 0.46% to 17.41%. The gas content of No. 9 CBM reservoir is weakly correlated with moisture and ash contents, whereas the CH₄ concentration is almost unaffected by coal quality characteristics. In addition, gas content and CH₄ concentration of the No. 8-2 CBM reservoir are positively correlated with buried depth, while N₂ and CO₂ concentrations are negatively correlated with buried depth.