煤层气“零点”理论及福建煤层低瓦斯原因研究

Study on“Zero-Point”Theory of Coaled Methane and the Causes of Low Coalbed Methane Content in Fujian

通过综合考虑煤层气的生成过程和逸散过程,确定煤层气的“零点”,即生成速度与逃逸速度相等的交叉点,“零点”之前是煤层气净增期,之后则是净减期。由此推断,距离地质历史上的“零点”时刻的长短决定了煤层气的损益比,也决定了煤层中气体含量的高低。运用该原理,对于福建煤层低瓦斯特点的原因进行了深度解剖。

By comprehensively considering the generation process and escape process ofcoalbed methane,the"Zero-Point"of coalbed methane is determined,which is the intersection point where the generation speed and escape rate are equal.The"Zero-Point"is preceded by the net increase period of coalbed methane,followed by the net reduction period.Therefore,the length of the“Zero-Point”time in geological history determines the profit-to-loss ratio of coalbed methane,also determines the level of gas content in the coalbed.The cause of the low gas content of the coal seam was deeply dissected in Fujian with this principle.