水温和粒子大小对煤炭氧化特性的结合作用:一项实验研究
Haojie Zhang1,2, Ziwen Dong1,2, Minyang Shen1,2
1School of Materials and Chemical Engineering/School of Safety Engineering, Ningbo University of Technology, Ningbo 315211, China.
ACS omega
|July 7, 2025
概括
煤炭氧化因颗粒大小和水温而发生显著变化. 较低的温度可以增加较大的粒子的激活能量,而较高的温度和较小的尺寸可以减少它,从而影响自发燃烧的风险.
科学领域:
- 煤炭科学 煤炭科学
- 化学动力学 化学动力学
- 材料科学是一种材料科学.
背景情况:
- 煤炭氧化是自发燃烧的一个关键因素.
- 了解颗粒大小等物理性质和水温等环境因素对风险评估的影响至关重要.
研究的目的:
- 研究煤粒大小和水温如何影响氧化反应特征.
- 为了确定在这些条件下控制煤炭氧化过程的动力模型.
- 评估对煤炭自燃风险的影响.
主要方法:
- 在不同大小的原始和浸水煤样本上使用编程温度的氧化实验.
- 对氧气消耗动力学的分析.
- 在不同条件下确定激活能量 (Ea).
主要成果:
- 阿弗拉米-埃罗菲模型 (n=4) 准确地描述了O2消耗反应动力学.
- 水温显著影响激活能量:较低的温度 (<15°C) 会增加较大的粒子 (>2.5mm) 的 Ea,而较小的粒子则会减少 Ea.
- 较高的水温 (≥30°C) 始终将 Ea 降低12-15%,在较小的颗粒大小和较高的温度下,可以看到更大的减少.
- 在15°C浸泡的混合颗粒大小的煤显示了增强的低温氧化,但抑制了高温氧化.
- 在30°C的温度下浸泡导致与原煤相比的氧化.
- 在45°C浸泡抑制了低温氧化,但显著增强了高温持续氧化,增加了自燃风险.
结论:
- 煤炭的氧化行为和自燃风险对颗粒大小和水温之间的相互作用非常敏感.
- 沉浸在水中,特别是在更高的温度下,可以显著改变煤炭的氧化特性,可能会增加高温自燃的风险.
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