Molecular dynamics study on the effect of minerals on the mechanical heterogeneity of anthracite coal:A case study of kaolinite in the southern part of the Qinshui Basin
ZHANG Bin;SUN Beilei;WANG Dezhang;KANG Tianhe;MA Xin;ZHANG Xiaoyu;LI Ligong;LI Haoyang;LIANG Xiaomin;ZHU Wenqing;ZHANG Junshuang
太原理工大学 原位改性采矿教育部重点实验室太原理工大学 矿业工程学院晋能控股装备制造集团有限公司太原理工大学 煤科学与技术教育部重点实验室煤炭科学研究总院有限公司 矿山大数据院天地科技股份有限公司煤炭智能开采与岩层控制全国重点实验室太原理工大学 经济管理学院
煤是由有机显微组分和矿物组成的混合物,矿物的存在会导致煤的大分子结构存在差异,使得煤的力学性质具有明显的非均质性,进而影响区块内整体的煤层气产量、压裂改造效果和成熟技术的规模化应用。以沁水盆地典型的无烟煤和高岭石矿物作为研究对象,通过分子动力学的方法定量研究高岭石及其含量对无烟煤力学性质的影响规律,分析不同矿物含量下无烟煤的分子结构和孔隙特征,从能量和有序化的角度揭示其微观机理。结果表明:① 煤有机质与高岭石相互结合过程中同时存在范德华力和氢键作用,且氢键作用强度要高于范德华力,煤有机质周围出现高岭石分子的概率、相互作用强度和有序性均随着矿物质量分数的增加而增大。② 无烟煤的孔隙率随高岭石质量分数的增大呈线性规律(
Coal is a mixture of organic macerals and minerals. The presence of minerals can lead to differences in the macromolecular structure of coal, resulting in significant heterogeneity in its mechanical properties, which in turn affects the overall coalbed methane production, fracturing and transformation effects, and the large-scale application of mature technologies within the block. Taking typical anthracite and kaolinite minerals from the Qinshui Basin as the research object, the influence of kaolinite and its content on the mechanical properties of anthracite is quantitatively studied through molecular dynamics methods. The molecular structure and pore characteristics of anthracite under different mineral contents are analyzed, and its microscopic mechanism is revealed from the perspective of energy and ordering. The results indicate that: ① There are both van der Waals forces and hydrogen bonding forces during the binding process between coal organic matter and kaolinite, and the intensity of hydrogen bonding is higher than that of van der Waals forces. The probability, interaction strength, and orderliness of kaolinite molecules appearing around coal organic matter increase with the increase of mineral content. ② The porosity of anthracite decreases linearly with the increase of kaolinite content, with
anthracite coal;kaolinite;heterogeneity;molecular dynamics;Qinshui Basin
主办单位:煤炭科学研究总院有限公司 中国煤炭学会学术期刊工作委员会