排采曲线在煤层气井评价中的应用

Production Curve to Evaluate Coalbed Gas

郝艳丽¹,姚慧智²,瞿定祥³

Hao Yanli , Yao Huizhi and Qu Dingxiang

1.中原油田分公司井下特种作业处,2.中原油田分公司采油工程技术研究院,3.中原油田分公司采油工程事业部

Downhole Special Service Division, Zhongyuan Oilfield Company, SINOPEC, Henan 457061, P. R. China

煤层气井的排采曲线是煤层生产能力的一个具体体现, 常规分析方法主要是把气、水产量随时间的变化曲线作为主要排采曲线进行排采分析。除此之外, 井底流压与气、水产量的变化关系曲线也是分析煤层排采动态的一个重要依据。对这2 种曲线进行分析和总结, 尤其是从井底流压与气、水产量的关系曲线中, 发现了3 个关键点和2 个关键阶段, 而且从中可以得出煤层的实际解吸压力这一关键参数。

The production curve of coalbed gas well is a specific reflect of its productivity. In general, we consider the curve which results from the production of the gas and water altering with the production time to be a essential curve to analyze coalbed. Besides this, the curve which shows that the production of the gas and water alters with the corresponding bottom flow pressure is also a critical basis in analyzing coalbed methane’s production activity. This paper conducts some analysis and summary to this two kinds of curves, especially it presents three critical points and two key phrases from the second curve, including the actual desorption pressure which is necesary and main in the production evaluation.