煤层气U型井钻井采气技术及应用

Coalbed methane U well drilling technology and its application

煤层气作为清洁能源的一种,也是我国能源接替战略中重要的一部分。我国煤层气储量约三十万亿立方米,其中高陡构造的煤层气占17.5%,且分布范围广。根据高陡构造煤层气开发存在地层倾角比较大、渗透率低、煤层非均质性强等难点,本文提出一种U型井钻井采气的技术,并基于某区块的地质条件,优化了配套的工艺技术。实践证明,U型井钻井采气技术可以有效的发挥直井开采稳定、成本较低和水平井控制面积大、生产速度快的优势,扩大高陡构造煤层气的排采区,有助于解决渗透率低、投资回报周期长等问题,对整个煤层开展降压、排水和采气。使用充气欠平衡钻井技术,通过优化注气压力、液排量等关键参数,能够降低储层的污染。借助组合U型井钻井采气技术,还可以使多口U型井共同使用一口直井排采,节约资源,提高效率。

Coal bed methane is a kind of clean energy,and an important part of energy to replace strategy in China. Coalbed methane reserves in our country about thirty trillion cubic meters, of the high and steep structure of coal-bed methane accounts for 17.5%,and the distribution range is wide. According to the high and steep structure of coalbed methane development low dip Angle is bigger, permeability, the coal seam, such as the strong heterogeneity, this paper proposes a u-shaped drilling gas extraction technology,and based on the geological conditions of a certain block,optimized the matching technology. Practice has proved that U well drilling extraction technology can effectively play a vertical well drilling stability, lower cost and the advantage of horizontal well control area is large,fast production,expanding the high and steep structure of coal-bed methane mining area, help solve problems such as low permeability, long investment return cycle, antihypertensive, drainage and gas extraction of the coal seam. Using aerated underbalance drilling technology,through the optimization of gas injection pressure,fluid rate,such as key parameters, can reduce the pollution of reservoir. Combination with U well drilling extraction technology, but also can make the multi-port U well together using a vertical line,save resources,improve efficiency.