延川南区块煤层气钻井防漏堵漏技术优化

Optimizing of the Technology of Lost Circulation Prevention and Control for CBM Drilling in Yanchuan South Block

鄂尔多斯盆地延川南区块由于受风化、地层运动等作用,裂隙发育、孔隙结构不稳定,储层区泥质煤岩节理发育,各个层位普遍存在漏失,井漏不仅延误了钻井周期而且容易导致钻井事故。文章分析了延川南区块漏失原因及井漏处理难点,针对不足,结合现有处理措施提出了优化方案,这有助于改进延川南区块防漏堵漏技术,降低储层污染。

Due to effect of weathering, strata movement and so on, the development of fissures, and pore structure in Yanchuan South Block of Erdos Basin is not stable, the jionts of the mud coal develops in the reservoir area, and each layer generally exists leakage, The well leakage not only delays the drilling peri- od and easily lead to drilling accident. This paper analyzes the causes of leakage occurred in Yanchuan South Block, as well as the difficulties of leakage treatment. To deal with the shortages, an optimization scheme is provided combined with the existing measures. It is of important significance to improve the technology of CBM well leakage prevention and control and reduce the reservoir pollution for Yanchuan South Block.