注入增产法提高煤层气采收率的理论探讨

美国Amoco公司开发的注入增产法是一项很有前途的提高煤层气采收率的方法，为此笔者在研究煤对二元气体吸附特征的基础上，探讨了注入增产法的基本原理。结果表明，煤对常见气体的吸附能力由强到弱为：二氧化碳、甲烷、氮气、氢气；煤对二元混合气体总的吸附及对甲烷的吸附均符合Langmiur方程，但在ＣＨ４＋Ｈ２或ＣＨ４＋Ｎ２的吸附系统中，对Ｈ２或Ｎ２吸附时吸附量与压力之间不遵从此关系式，而在ＣＨ４＋ＣＯ２吸附系统中，煤对ＣＯ２的吸附量和压力之间的关系仍可用Langmuir方程定量描述；注入增产法提高煤层瓦斯抽放率是通过注入其它气体使煤对甲烷的吸附量减小来实现的，且注入Ｎ２优于ＣＯ２。

Exploration on the Principle of ECMB

ECMB, which is developed by Amoco company in USA, has very prospective. On the basis of the study on adsorption characteristics of mixture gas in coal, the principle of ECMB has been explored. The order of adsorption capacities of coal for several gases is: CO 2>CH 4>N 2>H 2 when coal adsorbs gas. In 2 member mixture gases, adsorption capacities of coal for mixed gases, methane and carbon dioxide tally with Langmuir equation, but not does for nitrogen and hydrogen. The substance of the increasing drawing ratio of coal seam gas by using ECBM is decreasing adsorption amount of methane in coal by emptying the other gas or gases into coal seam. N 2 is better gas than CO 2 in the process of using ECMB.