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Updated: Sep 16, 2025

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Ammonia Synthesis at Low Pressure
Published on: August 23, 2017
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富含的合成气和稀释对在中等压力下氨气防火特性的影响
Minh Tien Nguyen1, Van Ga Bui2, Hong-Quan Do3
1The University of Danang - University of Technology and Education, 48 Cao Thang, Danang 50000, Vietnam.
ACS omega
|July 7, 2025
概括
在氨燃烧中添加合成气和气显著提高了燃烧速度和效率. 然而,稀释会阻碍燃烧性能. 本研究详细介绍了影响这些结果的关键反应.
科学领域:
- 燃烧科学与工程 燃烧科学与工程
- 化学动力学和反应机制.
- 其他燃料和排放控制
背景情况:
- 氨 (NH3) 是一个有前途的无碳燃料,但其燃烧特性需要优化用于实际应用.
- 了解合成气和稀释剂等辅助燃料的影响对于开发高效的氨燃烧策略至关重要.
- 合成气是 (H2) 和一氧化碳 (CO) 和 (N2) 的混合物,是燃料混合物和废气中常见的成分.
研究的目的:
- 为了研究合成气,缩合成气 (不同的H/C比率) 和稀释对氨气/空气燃烧的影响.
- 量化关键燃烧参数的变化,包括压力峰值,燃烧持续时间,压力上升速度和层状燃烧速度.
- 通过动力建模来识别影响层状燃烧速度的主导化学反应.
主要方法:
- 在3bar和300K的初始条件下,在恒定体积容器中进行实验性燃烧分析.
- 测量压力峰值 (pmax),燃烧持续时间 (tc),最大压力上升率 (dp/dt) max,和层状燃烧速度 (SL) 在等价比 (φ) 从0.8到1.3之间.
- 使用Mei-Mech进行反应途径灵敏度分析的计算分析.
主要成果:
- 增加的合成气比例和H/C比提高了pmax, (dp/dt) max,SL,并降低了tc.
- 稀释对燃烧性能产生了负面影响,显示了相反的趋势.
- NH3 / 合成气 / 空气混合物的层状燃烧速度 (SL) 达到 φ = 1.1 的峰值,与纯NH3火焰相比增加了 1.25 到 3.7 倍,从 7.5 到 22 厘米/秒不等.
- 灵敏度分析确定了关键反应:H + O2 = O + OH (R1) 和H + O2 (+ M) = HO2 (+ M) (R15) 在史泰基测量混合物中对SL占主导地位.
- 反应H2 + OH = H2O + H (R3) 显示,随着H/C比率的增加,净反应速率显著增加.
结论:
- 合成气的添加,特别是具有更高的H/C比率,是改善氨燃烧特性的有效策略.
- 作为稀释剂,抑制燃烧效率,在燃料混合物设计中需要仔细考虑.
- 动力建模为控制氨-合成气燃烧的反应途径提供了宝贵的见解,有助于进一步优化.
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