高煤级煤储层含水性特征及其对吸附能力的影响

为了研究高煤级煤储层含水性对吸附能力的影响，对阳泉-寿阳区块8件代表性煤样开展了镜质体反射率、显微组分、孔隙度、压汞、核磁共振和甲烷等温吸附等实验，分析了煤储层孔径分布、核磁共振T2谱响应特征、核磁孔隙度以及煤岩吸附能力，同时对煤储层含水性和煤储层吸附能力的相互关系进行了分析。研究结果表明：高煤级煤储层孔隙以微孔发育为主，孔隙含水性以微小孔中的束缚水赋存状态为主，且其含水量随最大镜质体反射率(Ro,m)的增大而增加。在影响高煤级煤储层吸附能力的多种因素中，煤储层含水性对煤岩吸附能力起着决定性的作用，尤其体现在微小孔中的束缚水对吸附能力的影响，束缚水含量越高，煤岩吸附能力越差。

Moisture content characteristics of high rank coal reservoir and its influence on adsorption capacity.

In order to study the effects of moisture content on adsorption capability of high rank coal reservoir, we conducted experimental investigations on eight representative coal samples collected from the YangquanShouyang block. Vitrinite reflectance, maceral composition and porosity measurements, combined with mercury injection, nuclear magnetic resonance (NMR) and methane isothermal adsorption experiments, were carried out to investigate pore size distribution, NMR T2 spectrum response, NMR porosity and adsorption capability of coal reservoir. Moisture contents in the water saturated coal samples were quantitatively characterized, and their impacts on methane adsorption capability were studied. The results showed that micropores dominate the pore structure in high rank coal; the bound water is the main source of moisture in micropores; and the bound water content shows a positive correlation with Ro,m. Moreover, among the factors affecting methane adsorption capacity, moisture content, especially bound water in micropores, plays a key role as higher bound water content corresponds to poorer methane adsorption capability.