煤的三维孔隙结构特征及其与吸附能力的关系
Bingyi Jia1,2, Shugang Li1, Kui Dong3
1School of Safety Science and Engineering, Xi'an University of Science and Technology, Xi'an 710000, China.
Materials (Basel, Switzerland)
|August 26, 2023
概括
了解煤孔状结构是煤床甲生产的关键. 原子力显微镜 (AFM) 和算法揭示了孔状特征和表面粗度,影响了气体吸附和容器效率.
科学领域:
- 地质和地球科学 地质和地球科学
- 材料科学 材料科学 材料科学
- 石油工程是石油工程中的一个.
背景情况:
- 煤储量异质,阻碍了煤床甲 (CBM) 的生产.
- 了解孔隙特性对于CBM提取效率和安全至关重要.
- 现有的方法,如低压气吸附 (LP-N2-GA) 提供宏观的视图,而原子力显微镜 (AFM) 提供纳米尺度的洞察力.
研究的目的:
- 综合分析煤样本的孔隙结构和表面粗度.
- 为了比较不同AFM算法 (Threshold vs. 陈的) 和放大 (×200 vs. ×4000) 孔隙特征的有效性.
- 研究孔隙结构,表面粗度和高压甲气体吸附 (HP-CH4-GA) 之间的关系.
主要方法:
- 原子力显微镜 (AFM) 技术用于六个煤样本 (1.19% < Ro,max < 2.55%).
- 在LP-N2-GA和AFM之间进行了微观形态的比较.
- 孔隙结构分析使用了值和陈的算法在×200和×4000放大,然后与HP-CH4-GA实验数据进行比较.
主要成果:
- AFM观察到V形和形毛孔,补充了LP-N2-GA更广泛的毛孔结构描绘.
- 陈的算法和4000倍的放大率提供了更准确的毛孔计数和毛孔度测量,与LP-N2-GA.更好地对齐.
- 较高的表面粗度 (Ra,Rq) 与气体吸附有积极的相关性,而增加的斜度 (Rsk) 和度 (Rku) 则显示出不利的影响.
结论:
- 选择的算法和放大显著影响煤中孔隙结构的评估.
- 3D算法和×4000放大率提供了更准确的孔隙结构描述.
- 与煤炭等级相关的表面粗度变化,在调节煤炭库中的气体吸附行为方面发挥着至关重要的作用.
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