煤岩储层保护技术研究进展

The Research Progress of Coal Reservoir Protection Techniques

中国煤岩储层具有低孔、低渗、裂缝发育但分布不均等特征,所以煤岩储层比常规储层更容易发生损害。煤岩储层的损害不仅导致煤层气采收率下降,且增加开发成本,延缓工程进程,严重制约煤层气的开发效果。主要从煤层气钻井完井及压裂、排采三个方面,介绍了损害发生的影响因素、过程机理、预防措施等研究进展,指出了煤层气的开发过程中外来流体不配伍、煤粉运移和压力变化等是诱发储层损害的主要因素,如何保护煤岩储层是煤层气经济、高效开发的重要条件。最后提出了煤岩储层保护技术存在的问题以及未来发展趋势,为保护煤岩储层发提供新的思路。

Coalbed formation has the characteristic of low-porosity, low-permeability, and developed-fracture but heterogeneous distribution in China. Therefore, compared to conventional formation, the formation of CBM has more possibility to be damaged. The formation damage of CBM can not only make the EOR of CBM declines, but also increase cost, delay engineering progress and seriously restrict development effect of CBM. Based on three progresses of drilling and completion, fracturing and drainage gas recovery, this paper introduces the influencing factors, progress mechanism and prevention action of the cause of formation damage. The paper points out factors such as incompatibility of foreign fluid, migration of pulverized coal and the change of pressure are the main causes of CBM formation damage. It also indicates that formation protection is a key point of economically and efficiently developing CBM resource. In the end, the paper put forward the existing problem and development tendency of the of CBM formation protection technology. It provides a new idea for the CBM formation protection technology.