有不同氧化度的氧化煤残留物的微观结构演变
Liangzhou Chen1,2, Xuyao Qi2, Wei Lu1
1College of Safety Science and Engineering, Anhui University of Science and Technology, Huainan 232001, China.
ACS omega
|July 1, 2024
概括
了解煤场火灾需要知道氧化煤如何反应. 较高的温度和氧气水平通过改变其结构和孔状网来降低煤炭的反应性,阻碍了气体扩散.
科学领域:
- 环境科学 环境科学
- 地质化学 地质化学
- 燃烧科学 燃烧科学
背景情况:
- 煤田火灾带来了重大的环境和安全风险.
- 了解氧化煤残留物的反应性对于消防管理至关重要.
- 氧化煤在火灾条件下的行为是复杂的,需要详细研究.
研究的目的:
- 研究氧气体积分和氧化温度如何影响氧化煤结构.
- 阐明火灾地区煤炭反应性降低背后的机制.
- 为了确定煤田火灾的代表性氧化条件.
主要方法:
- 氧化煤残留物的工业和元素分析.
- 红外扩散反射光谱学.红外扩散反射光谱学.
- 特定表面积和孔隙大小分布分析.
主要成果:
- 温度升高和氧气体积分数增加会减少挥发物质和固定碳,特别是在400°C以上.
- 在高氧气下,基团随着温度升高而减少;在较低的温度下,高氧气下,基团增加.
- 缺乏氧气,高温条件强化了煤炭结构,减少了芳碳化合物凝结. 氧化会改变孔腔形态,消耗碳基质并减少微孔,从而阻碍内部气体扩散.
结论:
- 升高的温度和氧气水平通过修改其内部结构和毛孔网络来降低煤炭的反应性.
- 缺氧燃烧和结构增强有助于降低反应能力.
- 变化的孔腔形态和减少的内部气体扩散是氧化煤在火灾区反应性降低的关键因素.
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