由于液体CO2相变喷射而引起的煤炭裂的传播行为,考虑到喷射压力效应的喷射压力
Shu Ma1,2, Guiming Li2,3, Yongjiang Zhang4
1School of Safety Engineering, China University of Mining and Technology, Xuzhou, China.
PloS one
|November 15, 2024
概括
液态二氧化碳在煤层中的相位变化喷射会随着压力增加而产生更复杂的裂. 这种破碎过程涉及冲击波和应力,为优化喷射设计提供了洞察力.
科学领域:
- 地质技术工程 地质技术工程
- 岩石机械学 岩石机械学
- 采矿工程 采矿工程 采矿工程
背景情况:
- 低透性煤层对传统的压裂方法构成挑战.
- 液态二氧化碳 (CO2) 阶段变化喷射为岩石破裂提供了一种新的方法.
- 了解裂传播机制对于有效的现场压力管理至关重要.
研究的目的:
- 为了研究由液态CO2相变喷射引起的低透性煤层中裂纹传播机制.
- 分析不同喷射压力对故障模式,裂形态和分布的影响.
- 为了阐明二氧化碳喷射中冲击波和准静态应力之间的相互作用.
主要方法:
- 使用小规模液态CO2相变喷射试验系统进行实验研究.
- 对煤岩模型样本的分析,这些样本受到不同的二氧化碳喷射压力.
- 观察和描述裂形状,膨胀过程和故障区域.
主要成果:
- 爆炸压力的增加显著增加了裂的数量和复杂性.
- 裂纹模式从简单的线性断裂演变为复杂的多方向网络.
- 确定了明显的故障区域 (断裂区域和裂纹区域),由冲击波和拉伸应力驱动.
结论:
- 在煤层中,液态CO2相变喷射的有效性取决于压力.
- 裂的产生和传播是由冲击波和CO2相变压的联合作用决定的.
- 结果为优化矿业应用中的液态二氧化碳相变压裂设计提供了有价值的数据.
更多相关视频
10:06Microfluidic Fabrication Techniques for High-Pressure Testing of Microscale Supercritical CO2 Foam Transport in Fractured Unconventional Reservoirs
Published on: July 2, 2020
6.7K
06:26Achieving Moderate Pressures in Sealed Vessels Using Dry Ice As a Solid CO2 Source
Published on: August 17, 2018
9.9K
相关概念视频
Phase Diagrams
39.9K
A phase diagram combines plots of pressure versus temperature for the liquid-gas, solid-liquid, and solid-gas phase-transition equilibria of a substance. These diagrams indicate the physical states that exist under specific conditions of pressure and temperature and also provide the pressure dependence of the phase-transition temperatures (melting points, sublimation points, boiling points). Regions or areas labeled solid, liquid, and gas represent single phases, while lines or curves represent...
39.9K
Microcracking in Concrete
103
Microcracking in concrete refers to the tiny cracks that can form within the material even before any external load is applied. These microcracks typically occur at the interface between the coarse aggregate and the hydrated cement paste, often as a result of differential volume changes prompted by variations in stress-strain behavior, as well as thermal and moisture movement. Initially, these microcracks remain stable and do not grow substantially until the concrete is stressed to about 30...
103
Porosity in Cement Paste
117
The porosity of concrete is a measure of the void spaces within its structure. These spaces impact its strength and durability significantly. When water and cement interact, a chemical reaction called hydration creates a semi-solid paste. This paste includes combined water, making up approximately 23% of the cement's dry mass, and gel water, which fills minuscule voids known as gel pores, accounting for about 28% of the cement gel volume.
The balance of water to cement in the mix is...
The balance of water to cement in the mix is...
117
Turbulent Flow: Problem Solving
96
Carbonation is a process used to dissolve carbon dioxide gas in a liquid, commonly used in the production of carbonated beverages. Achieving efficient carbonation requires careful control of temperature, pressure, and flow conditions. By adjusting these parameters, carbonation efficiency can be maximized, producing a higher concentration of CO2 in the liquid.
Temperature is a key factor in CO2 solubility. In this case, the CO2 gas and the liquid are cooled to 20°C. Lower temperatures...
Temperature is a key factor in CO2 solubility. In this case, the CO2 gas and the liquid are cooled to 20°C. Lower temperatures...
96
Effects of Air-entrainment in Concrete
80
Air entrainment in concrete significantly enhances the material's durability, especially in environments subjected to freeze-thaw cycles. Introducing small air bubbles into the concrete mix acts as internal voids that accommodate the expansion of water when it freezes, thereby alleviating internal stress and preventing structural cracks. This function is crucial in climates with significant freezing and thawing, as it protects the concrete from repeated stresses that could lead to premature...
80
Carbonation Shrinkage
110
Atmospheric CO2 penetrates the concrete's pores and, in the presence of moisture, forms carbonic acid, which then reacts with calcium hydroxide in the hydrated cement, forming calcium carbonate. This process reduces the concrete's volume and is termed carbonation shrinkage.
The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction...
The concrete's permeability is slightly reduced as calcium carbonate produced during the reaction fills its pores. Furthermore, its strength is slightly enhanced as the water released during the reaction...
110
