沁水盆地南部煤层气田防膨综合分析研究

Comprehensive Analysis of Anti-swelling for Coalbed Methane Fields in South of Qinshui Basin

目前,煤储层改造的主体工艺仍然是活性水压裂技术。但是对于煤层防膨问题,基本都是基于砂岩理论的防膨技术研究,未针对煤层进行全面研究讨论。针对这一问题,通过对煤层粘土含量分析确定储层好与差;分析了排采过程中煤岩与砂岩渗透性变化特征;并进行了煤层气井防膨现场对比试验,同时,结合环境保护及开发成本进行了全面分析,认为一般区块煤层不需要进行防膨措施,而对于差的储层区域所占比例高于20%的开发区块,建议进行现场试验,进一步确定是否采取防膨措施。

At present,the main process of coal reservoir reconstruction is still hydraulic fracturing technology.However,for the anti-swelling problem of coal seams,although there are many studies on antiswelling technology based on sandstone theory,there is no comprehensive research and discussion on coal seams.In this paper,the reservoirs are determined to be good or poor based on the analysis of coalbed clay content and the characteristics of permeability change of coal and sandstone during drainage process are analyzed.The anti-swelling comparative test is carried out.The environmental protection and development cost have been analyzed,and it is considered that ordinary coal seams do not require anti-swelling measures.For the other block where the proportion of the poor reservoir area is higher than 20%,it is recommended to conduct field tests for further determine whether to take anti-swelling measures.