沁水盆地南部15号煤储层物性特征分析

Physical Characteristics Analysis of No. 15 Coal Reservoir in Southern Qinshui Basin

为了探讨沁水盆地南部研究程度尚低的15号煤储层在煤岩煤质、孔-裂隙、渗透性、吸附性等方面的特征,运用矿物测试、宏观微观观察、压汞、低温液氮等温吸附测试等方法并结合煤层气井数据分析,对15号煤与3号煤进行对比研究。结果表明:15号煤显微组分特征有利于孔-裂隙发育和产气率,吸附性较好、含气量较高,裂隙较为发育;矿物种类多、含量高,矿物充填了孔-裂隙,严重降低了孔隙结构优度和渗透率。因此矿物充填,低渗透率和孔隙结构差是制约15号煤煤层气开发的主要因素。

In order to study the characteristics of coal and rock,hole- fissures,permeability,absorption and other aspects for No. 15 coal reservoir in southern Qinshui Basin,its research degree is still low. Combined with the data analysis of coalbed methane well,some methods are used to carry out comparative study for No. 15 coal and No. 3 coal,such as mineral test,macro and micro observation,mercury,isotherm adsorption test of low temperature liquid nitrogen and so on. The results show that the maceral features of No.15 coal are beneficial to the development of pore- fracture and gas production rate. It has a good adsorption ability and high gas content,the pore- fracture develops well. Some aspects,for example much mineral variety,high content,mineral fills with hole- fissures,can severely reduce the pore structure and permeability. Therefore,the mineral filling,low permeability and poor pore structure are the major factors restricting the coalbed methane development of No. 15 coal.