基于核磁共振放松光谱学的煤炭自发浸泡的实验研究
Xiangzhong Luo1, Chaolin Wang2, Yu Zhao1
1College of Civil Engineering, Guizhou University, Guiyang, Huaxi District, 550025, Guizhou, China.
Scientific reports
|February 20, 2025
概括
这项研究揭示了水如何转移到煤炭中,表明毛孔发育,而不仅仅是大小,驱动毛细血管吸收水. 微孔首先填充,影响煤床甲的提取和液压操作.
科学领域:
- 地质地质地质地质地质地
- 石油工程是石油工程中的一个.
- 材料科学 材料科学 材料科学
背景情况:
- 煤炭中自发的水浸泡对于水力运行和煤床甲 (CBM) 提取至关重要.
- 了解煤孔结构会影响流体流动和CBM回收效率.
研究的目的:
- 阐明煤炭在不同级别的自发水浸泡机制.
- 为了研究微观的水迁移特征及其与毛孔结构的关系.
- 为了将核磁共振 (NMR) 成像参数与毛细血管吸收和毛孔发育相关联.
主要方法:
- 低场核磁共振 (NMR) T2光谱和成像 (MRI) 用于分析煤炭样本中的水分布.
- 将NMR数据与孔隙结构分析结合起来,以了解水的迁移.
- 研究了MRI像素固有值,毛细血管吸收系数和毛孔发育指标之间的关系.
主要成果:
- 毛细血管水吸收系数与毛孔发育程度之间存在正相关性.
- 在吸收系数和孔径/扭曲度之间发现了负相关性.
- 微孔首先和,其次是中孔和大孔 (包括微骨折).
- 水的迁移开始于煤炭内部,然后向外移动.
- 较高的MRI像素固有值表明较大的孔含量,随机孔分布和增强的孔连接性,导致吸收增加.
结论:
- 孔隙发育程度和连接性是控制煤炭中自发水浸泡的关键因素.
- 核磁共振成像为微观水运输机制和毛孔结构特征提供了宝贵的见解.
- 这些发现增强了对优化液压压裂和CBM恢复的理解.
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