时间依赖模型和动态扩散系数的演变机制,用于气体含有煤气中的气体吸附
Honglai Xue1,2, Xiangyang Zhang2, Zhe Wen3,4
1School of Safety Science and Engineering, Changzhou University, Changzhou 213164, PR China.
ACS omega
|December 18, 2023
概括
这项研究开发了一种新的依赖时间的煤床甲扩散系数模型,这对于预测气体排水和防止爆发至关重要. 该模型经过实验验证,显示孔隙结构显著影响扩散动态.
科学领域:
- 地球科学 地球科学 地球科学
- 化学工程是化学工程的重要组成部分.
- 材料科学 材料科学 材料科学
背景情况:
- 煤床甲 (CBM) 排水对于清洁能源和减轻煤炭和天然气爆发至关重要.
- CBM存在于煤层中吸附,通过孔隙网络扩散到管道.
- 现有的动态扩散系数模型缺乏严格的理论验证.
研究的目的:
- 开发和验证煤床甲动态扩散系数的时间依赖模型.
- 阐明控制煤层气体扩散的进化机制.
- 为了解煤炭中的气体扩散提供理论基础.
主要方法:
- 提出了一个进化机制,整合了碎形理论,表面物理化学和多孔介质扩散理论.
- 根据拟议的机制推导出动态扩散系数的时间依赖模型.
- 进行数值计算和实验验证以验证模型.
主要成果:
- 煤炭中气体脱吸的扩散系数表现出动态特征.
- 扩散系数与孔隙碎形尺寸和气体吸附效应负相关.
- 扩散系数与煤矩阵吸附能力正相关,孔隙结构是主要因素.
结论:
- 已建立的依赖时间的模型准确地预测了煤床甲扩散系数,与实验数据 (R2>96.0%) 保持一致.
- 孔隙结构,煤矩阵吸附能力和气体吸附效应共同影响动态扩散特性.
- 这项研究为了解煤层中的气体扩散机制提供了一个强大的理论框架.
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