新疆地区低煤阶煤层孔隙特征实验评价研究

Experimental Evaluation of Pore Characteristics of Low Rank Coal Seams in Xinjiang

近年来,随着新疆低煤阶煤层气勘探开发的突破,低煤阶煤层气储层评价受到重视。本研究以新疆低煤阶煤样为研究对象,通过低温N_2吸附实验、低温CO_2吸附实验以及高压压汞实验相结合的方法,分析全孔径分布特征。成果如下:高压压汞实验显示原生结构孔隙中的大孔和微孔较发育;低温N_2吸附实验显示孔隙以微孔为主,为开放型"墨水瓶"孔隙;低温CO_2等温吸附实验显示在相对压力较低时,CO_2吸附量以单层吸附方式能快速上升;通过上述实验的综合研究,发现低煤阶煤样全孔径分布曲线均呈双峰模式,微孔、大孔较为发育,其中微孔最发育。

In recent years,with the breakthrough of exploration and development of low coal rank coalbed methane in Xinjiang,the evaluation of low coal rank coalbed methane reservoir has been paid more attention.In this study,the distribution characteristics of full pore size of low rank coal samples in Xinjiang were evaluated.The results showed that the macropores and micropores in the primary structural pores were more developed in the high-pressure mercury injection test.The low temperature N2 adsorption experiment shows that the pores are mainly micropores,which are open"ink bottle"pores.The distribution curves of full pore size of low rank coal samples all show a bimodal pattern,and the micropores and macropores are more developed,among which the micropores are the most developed.