The pore evolution history varies with different types of macerals. The pore characteristics of the Huolinhe lignite of the Erlian Basin were examined under laboratory thermal maturation conditions to study the correlation of coal rank and macerals on pore evolution. Mercury intrusion porosimetry, low-pressure CO₂ adsorption, light microscopy, and scanning electron microscopy (SEM) were used to characterize the pores of macerals developed during different stages of pyrolysis. The results suggest that evolution of pores can be divided into three stages: maximum reflectivity of vitrinite (R_{o, max}) < 0.55% (first stage), 0.55% < R_{o, max} < 1.70% (second stage) and R_{o, max} > 1.70% (third stage). The proportion of pore area of macerals in vitrinite decreased at R_{o, max} < 0.55%, and then increased with the R_{o, max} in the range of 0.55–3.35%, while the collodetrinite had the maximum proportion of pore area (4–38%). The volume and specific surface area of different pore sizes first decreased and then increased with increase in coal rank. Moreover, most of the gas pores were mesopores, whereas the plant tissue pores and mold pores were macropores. The SEM analysis indicated that the generation of gas pores was dominant in collodetrinite. Therefore, the content of collodetrinite had a significant influence on the content of coalbed methane and pore structure of the coal reservoir.

孔的演变历史随不同类型的微晶石而变化。在实验室热成熟条件下，对二连盆地霍林河褐煤的孔隙特征进行了研究，以研究煤级和宏观特征与孔隙演化的相关性。汞入侵孔隙率法，低压CO ₂吸附，光学显微镜和扫描电子显微镜（SEM）用来表征在热解不同阶段所形成的微孔的孔隙。结果表明，孔隙的演化可分为三个阶段：镜质体的最大反射率（R _o，max）<0.55％（第一阶段），0.55％<  R _o，max  <1.70％（第二阶段）和R _{o，最大限度} > 1.70％（第三阶段）。在R _o处，黄水晶中的孔道面积比例下降_，最大值 <0.55％，然后在R _{o max处}增加_，最大值在0.55-3.35％范围内，而软锰矿的孔面积比例最大（4– 38％）。随着煤级的提高，不同孔径的体积和比表面积先减小后增大。此外，大多数气孔是中孔，而植物组织孔和霉菌孔是大孔。SEM分析表明，气孔的产生在软锰矿中占主导地位。因此，软锰矿的含量对煤层甲烷的含量和储层孔隙结构有显着影响。