高级检索

构造煤煤层气解吸阶段分析及最大瞬时解吸量计算

Analysis on coalbed methane desorption stage and calculation on max instant desorption value of tectonic coal

  • 摘要: 为了探求构造煤煤层气解吸阶段瞬时特征,选取平顶山五矿的构造煤和原生结构煤,分别在20、30、40℃下进行了甲烷等温吸附/解吸试验,以试验结果为基础构建了基于兰氏方程曲率的煤层气解吸阶段模型,并依据此模型分析了构造煤煤层气解吸阶段,探讨了构造煤煤层气最大瞬时解吸量。结果表明:随温度的逐渐升高和煤体破坏程度的增大,原生结构煤和构造煤的低效解吸阶段、缓慢解吸阶段、高效解吸阶段及敏感解吸阶段总体向低压方向偏移,启动压力、转折压力和敏感压力表现出减小趋势,相比原生结构煤,构造煤的大部分启动压力和转折压力更低,整个解吸阶段具有更明显的向低压偏移的特征;较大的兰氏体积使得高效解吸和敏感解吸阶段前移;同时,随着温度的升高,原生结构煤和构造煤的煤层气最大瞬时解吸量呈减小趋势。

     

    Abstract: In order to research the coalbed methane desorption stage and desorption instant features of the tectonic coal,the tectonic coal and in- situ structure coal fr om Pingdingshan No. 5 Mine were selected,a methane isothermal adsorption 1 desorption test was conducted under temperature of 20、30、 40。C individually. Based on th e test,a coalbed methane desorption stage model was established based on Langmuir equation curvature and was applied to analyze the coalbed methane desorption stag e of the tectonic coal and discuss the max instant desorption value of the coalbed methane from the tectonic coal. The results showed that with the temperature steadily inc reased and the coal failure degree increased,a low efficient desorption stage,slow desorption stage,high efficient desorption stage and sensitive desorption stage of the in- situ structure coal and tectonic coal would move to the low pressure direction generally,and the start pressure,turning pressure and sensitive pressure would be in a reducti on tendency. In comparison with the in- situ structure coal,the major start pressure and turning pressure of the tectonic coal would be more lower and the total desorption s tage would have more obvious to low pressure moving features. On the other hand,the large Langmuir volume would be favorable to the high efficient desorption and sensit ive desorption early coming. Meanwhile,with the temperature increased,the max desorption value of the coalbed methane from the in- situ structure coal and tectonic coal would be in a small reduction tendency.

     

/

返回文章
返回