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Ammonia Synthesis at Low Pressure
Published on: August 23, 2017
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在密切合的SCR中,氨在稳定和暂时状态下存储和滑动
Shiyu Liu1, Zhaohuan Zhang1, Zexian Guo1
1State Key Laboratory of Automotive Safety and Energy, Tsinghua University, Beijing 100084, China.
Journal of environmental sciences (China)
|December 22, 2023
概括
在密切合的选择性催化减排 (cc-SCR) 系统中优化氨存储是减少冷启动NOx排放的关键. 这项研究确定了稳定和过渡状态的最佳水平,平衡效率和氨滑动.
科学领域:
- 汽车工程 汽车工程
- 环境科学 环境科学
- 催化剂是一种催化剂.
背景情况:
- 密切合的选择性催化减排 (cc-SCR) 对于减轻排气管NOx排放至关重要,特别是在发动机冷启动期间.
- 了解氨存储动态对于优化cc-SCR性能和最小化环境影响至关重要.
研究的目的:
- 调查和确定CC-SCR催化剂在稳定状态和短暂运行条件下的最佳氨存储水平.
- 分析NOx转换效率与氨滑动之间的权衡.
主要方法:
- 利用帕雷托解决方案,在稳定状态条件下确定最佳的氨存储,遵守中国VI排放标准.
- 开发了一种基于氨吸附/溶解动力学的简化0-D计算方法,以预测短暂的氨滑动.
- 分析了氨存储,催化剂温度和温度增加率对氨滑动的影响.
主要成果:
- 在稳定状态下,最优的氨储存被确定为氨滑落低于10μL/L.
- 短暂的条件,特别是温度的快速上升,可能会导致大量的氨滑.
- 在短暂条件下最优的氨存储比稳定状态要低得多,特别是在较低的温度下.
- 创建了一个相位图来说明温度和加热速度对最佳氨存储的影响.
结论:
- 最佳的氨储存策略在稳定状态和过渡性运行之间存在显著差异.
- 储存氨的有效管理对于满足严格的排放法规而保持高NOx减排效率至关重要.
- 拟议的瞬态计算方法和相位图为cc-SCR系统设计和校准提供了有价值的工具.
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