榆神府矿区富油煤煤相及孔隙结构特征试验研究

Coal facies characteristics and pore structure response of oil-rich coal in Yushenfu Mining Area

为研究成煤环境对煤样孔隙结构的影响,以榆神府矿区柠条塔、张家峁煤矿富油煤为研究对象,开展显微煤岩组分定量与煤相分析,通过压汞法分析其孔径分布与孔隙结构特征,探究了该区域富油煤孔隙结构特征与煤相存在的内在联系。研究发现:榆神府矿区富油煤沼泽类别以湿地草本沼泽相和干燥森林沼泽相为主,动水能力较弱;立足于柠条塔、张家峁富油煤孔隙结构对比,柠条塔2-2煤小孔、中孔、大孔发育较为均衡,而张家峁4-2煤中的小孔、中孔发育较好,大孔发育相对较差;对榆神府矿区富油煤而言,在相似煤阶条件下,其TPI煤相特征主要控制着大孔发育状况,并间接影响着煤储层后期低温热解效率。

To study the influence of coal-forming environment on the pore structure of coal samples, we take the oil-rich coals from Ningtiaota and Zhangjiamao coal mines in Yushenfu Mining Area as the research object, carry out quantitative analysis of microcoal composition and coal facies, and determine the pore size distribution and pore structure characteristics of the oil-rich coal in this area by mercury intrusion method. Finally, the response mechanism of coal facies to coal pore structure is revealed.The results of the study found that: Shenmu oil-rich coal swamps are dominated by wetland herbaceous swamp facies and dry forest swamp facies, with weak hydrodynamic capacity;based on the comparison of the pore structure of Ningtiaota and Zhangjiamao oil-rich coals, the small, medium, and macropores in Ningtiaota 2-2 coal are more balanced, Zhangjiamao 4-2 coal has better small and mesopores and the development of macropores is relatively poor;for the oil-rich coal in the Yushenfu Mining Area, under similar coal rank conditions, its TPI coal facies characteristics mainly control the development of macropores, and indirectly affect the late-stage low-temperature pyrolysis efficiency of coal reservoirs.